github.com/koding/cache 2014-09-12 2016-12-22

go.mod

@@ -17,7 +17,7 @@ require (
 	github.com/ianschenck/envflag v0.0.0-20140720210342-9111d830d133
 	github.com/joho/godotenv v1.3.0
 	github.com/json-iterator/go v1.1.10 // indirect
-	github.com/koding/cache v0.0.0-20140912085602-487fc0ca06f9
+	github.com/koding/cache v0.0.0-20161222233015-e8a81b0b3f20
 	github.com/lib/pq v0.0.0-20161103024354-d8eeeb8bae88
 	github.com/mattn/go-sqlite3 v0.0.0-20150427235825-542ae647f860
 	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
@@ -35,5 +35,6 @@ require (
 	google.golang.org/protobuf v1.25.0 // indirect
 	gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c // indirect
 	gopkg.in/gorp.v1 v1.7.1 // indirect
+	gopkg.in/mgo.v2 v2.0.0-20190816093944-a6b53ec6cb22 // indirect
 	gopkg.in/yaml.v2 v2.4.0 // indirect
 )

go.sum

@@ -61,8 +61,8 @@ github.com/joho/godotenv v1.3.0/go.mod h1:7hK45KPybAkOC6peb+G5yklZfMxEjkZhHbwpqx
 github.com/json-iterator/go v1.1.9/go.mod h1:KdQUCv79m/52Kvf8AW2vK1V8akMuk1QjK/uOdHXbAo4=
 github.com/json-iterator/go v1.1.10 h1:Kz6Cvnvv2wGdaG/V8yMvfkmNiXq9Ya2KUv4rouJJr68=
 github.com/json-iterator/go v1.1.10/go.mod h1:KdQUCv79m/52Kvf8AW2vK1V8akMuk1QjK/uOdHXbAo4=
-github.com/koding/cache v0.0.0-20140912085602-487fc0ca06f9 h1:wAnE6YoDViB3XyrvdSL9M+9EuVnWeAe9LQT1SgZm+pU=
-github.com/koding/cache v0.0.0-20140912085602-487fc0ca06f9/go.mod h1:sh5SGGmQVGUkWDnxevz0I2FJ4TeC18hRPRjKVBMb2kA=
+github.com/koding/cache v0.0.0-20161222233015-e8a81b0b3f20 h1:R7RAW1p8wjhlHKFhS4X7h8EePqADev/PltCmW9qlJoM=
+github.com/koding/cache v0.0.0-20161222233015-e8a81b0b3f20/go.mod h1:sh5SGGmQVGUkWDnxevz0I2FJ4TeC18hRPRjKVBMb2kA=
 github.com/kr/pretty v0.2.1 h1:Fmg33tUaq4/8ym9TJN1x7sLJnHVwhP33CNkpYV/7rwI=
 github.com/kr/pretty v0.2.1/go.mod h1:ipq/a2n7PKx3OHsz4KJII5eveXtPO4qwEXGdVfWzfnI=
 github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
@@ -165,6 +165,8 @@ gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c h1:Hei/4ADfdWqJk1ZMxUNpqntN
 gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c/go.mod h1:JHkPIbrfpd72SG/EVd6muEfDQjcINNoR0C8j2r3qZ4Q=
 gopkg.in/gorp.v1 v1.7.1 h1:GBB9KrWRATQZh95HJyVGUZrWwOPswitEYEyqlK8JbAA=
 gopkg.in/gorp.v1 v1.7.1/go.mod h1:Wo3h+DBQZIxATwftsglhdD/62zRFPhGhTiu5jUJmCaw=
+gopkg.in/mgo.v2 v2.0.0-20190816093944-a6b53ec6cb22 h1:VpOs+IwYnYBaFnrNAeB8UUWtL3vEUnzSCL1nVjPhqrw=
+gopkg.in/mgo.v2 v2.0.0-20190816093944-a6b53ec6cb22/go.mod h1:yeKp02qBN3iKW1OzL3MGk2IdtZzaj7SFntXj72NppTA=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.2.8/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.4.0 h1:D8xgwECY7CYvx+Y2n4sBz93Jn9JRvxdiyyo8CTfuKaY=

vendor/github.com/koding/cache/.travis.yml

@@ -1,3 +1,18 @@
 language: go
-go: 1.3
-script: go test ./...
+
+sudo: false
+
+services:
+  - mongodb
+
+install:
+  - go get -t -v ./...
+
+go:
+  - 1.4.3
+  - 1.5.4
+  - 1.6.2
+
+script:
+  - export GOMAXPROCS=$(nproc) # go1.4
+  - go test -race ./...

vendor/github.com/koding/cache/LICENCE

@@ -0,0 +1,21 @@
+The MIT License (MIT)
+
+Copyright (c) 2016 Koding, Inc.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

vendor/github.com/koding/cache/README.md

@@ -30,3 +30,16 @@ err := cache.Set("test_key", "test_data")
 // get item
 data, err := cache.Get("test_key")
 ```
+
+
+## Supported caching algorithms:
+
+- MemoryNoTS  : provides a non-thread safe in-memory caching system
+- Memory      : provides a thread safe in-memory caching system, built on top of MemoryNoTS cache
+- LRUNoTS     : provides a non-thread safe, fixed size in-memory caching system, built on top of MemoryNoTS cache
+- LRU         : provides a thread safe, fixed size in-memory caching system, built on top of LRUNoTS cache
+- MemoryTTL   : provides a thread safe, expiring in-memory caching system,  built on top of MemoryNoTS cache
+- ShardedNoTS : provides a non-thread safe sharded cache system, built on top of a cache interface
+- ShardedTTL  : provides a thread safe, expiring in-memory sharded cache system, built on top of ShardedNoTS over MemoryNoTS
+- LFUNoTS     : provides a non-thread safe, fixed size in-memory caching system, built on top of MemoryNoTS cache
+- LFU         : provides a thread safe, fixed size in-memory caching system, built on top of LFUNoTS cache

vendor/github.com/koding/cache/doc.go

@@ -1,9 +1,14 @@
 // Package cache provides basic caching mechanisms for Go(lang) projects.
 //
 // Currently supported caching algorithms:
-//     MemoryNoTS: provides a non-thread safe in-memory caching system
-//     Memory    : provides a thread safe in-memory caching system, built on top of MemoryNoTS cache
-//     LRUNoTS   : provides a non-thread safe, fixed size in-memory caching system, built on top of MemoryNoTS cache
-//     LRU       : provides a thread safe, fixed size in-memory caching system, built on top of LRUNoTS cache
-//     MemoryTTL : provides a thread safe, expiring in-memory caching system,  built on top of MemoryNoTS cache
+//     MemoryNoTS  : provides a non-thread safe in-memory caching system
+//     Memory      : provides a thread safe in-memory caching system, built on top of MemoryNoTS cache
+//     LRUNoTS     : provides a non-thread safe, fixed size in-memory caching system, built on top of MemoryNoTS cache
+//     LRU         : provides a thread safe, fixed size in-memory caching system, built on top of LRUNoTS cache
+//     MemoryTTL   : provides a thread safe, expiring in-memory caching system,  built on top of MemoryNoTS cache
+//     ShardedNoTS : provides a non-thread safe sharded cache system, built on top of a cache interface
+//     ShardedTTL  : provides a thread safe, expiring in-memory sharded cache system, built on top of ShardedNoTS over MemoryNoTS
+//     LFUNoTS     : provides a non-thread safe, fixed size in-memory caching system, built on top of MemoryNoTS cache
+//     LFU         : provides a thread safe, fixed size in-memory caching system, built on top of LFUNoTS cache
+//
 package cache

vendor/github.com/koding/cache/lfu.go

@@ -0,0 +1,49 @@
+package cache
+
+import "sync"
+
+// LFU holds the Least frequently used cache values
+type LFU struct {
+	// Mutex is used for handling the concurrent
+	// read/write requests for cache
+	sync.Mutex
+
+	// cache holds the all cache values
+	cache Cache
+}
+
+// NewLFU creates a thread-safe LFU cache
+func NewLFU(size int) Cache {
+	return &LRU{
+		cache: NewLFUNoTS(size),
+	}
+}
+
+// Get returns the value of a given key if it exists, every get item will be
+// increased for every usage
+func (l *LFU) Get(key string) (interface{}, error) {
+	l.Lock()
+	defer l.Unlock()
+
+	return l.cache.Get(key)
+}
+
+// Set sets or overrides the given key with the given value, every set item will
+// be increased as usage.
+// when the cache is full, least frequently used items will be evicted from
+// linked list
+func (l *LFU) Set(key string, val interface{}) error {
+	l.Lock()
+	defer l.Unlock()
+
+	return l.cache.Set(key, val)
+}
+
+// Delete deletes the given key-value pair from cache, this function doesnt
+// return an error if item is not in the cache
+func (l *LFU) Delete(key string) error {
+	l.Lock()
+	defer l.Unlock()
+
+	return l.cache.Delete(key)
+}

vendor/github.com/koding/cache/lfu_nots.go

@@ -0,0 +1,226 @@
+package cache
+
+import "container/list"
+
+// LFUNoTS holds the cache struct
+type LFUNoTS struct {
+	// list holds all items in a linked list
+	frequencyList *list.List
+
+	// holds the all cache values
+	cache Cache
+
+	// size holds the limit of the LFU cache
+	size int
+
+	// currentSize holds the current item size in the list
+	// after each adding of item, currentSize will be increased
+	currentSize int
+}
+
+type cacheItem struct {
+	// key of cache value
+	k string
+
+	// value of cache value
+	v interface{}
+
+	// holds the frequency elements
+	// it holds the element's usage as count
+	// if cacheItems is used 4 times (with set or get operations)
+	// the freqElement's frequency counter will be 4
+	// it holds entry struct inside Value of list.Element
+	freqElement *list.Element
+}
+
+// NewLFUNoTS creates a new LFU cache struct for further cache operations. Size
+// is used for limiting the upper bound of the cache
+func NewLFUNoTS(size int) Cache {
+	if size < 1 {
+		panic("invalid cache size")
+	}
+
+	return &LFUNoTS{
+		frequencyList: list.New(),
+		cache:         NewMemoryNoTS(),
+		size:          size,
+		currentSize:   0,
+	}
+}
+
+// Get gets value of cache item
+// then increments the usage of the item
+func (l *LFUNoTS) Get(key string) (interface{}, error) {
+	res, err := l.cache.Get(key)
+	if err != nil {
+		return nil, err
+	}
+
+	ci := res.(*cacheItem)
+
+	// increase usage of cache item
+	l.incr(ci)
+	return ci.v, nil
+}
+
+// Set sets a new key-value pair
+// Set increments the key usage count too
+//
+// eg:
+// cache.Set("test_key","2")
+// cache.Set("test_key","1")
+// if you try to set a value into same key
+// its usage count will be increased
+// and usage count of "test_key" will be 2 in this example
+func (l *LFUNoTS) Set(key string, value interface{}) error {
+	return l.set(key, value)
+}
+
+// Delete deletes the key and its dependencies
+func (l *LFUNoTS) Delete(key string) error {
+	res, err := l.cache.Get(key)
+	if err != nil && err != ErrNotFound {
+		return err
+	}
+
+	// we dont need to delete if already doesn't exist
+	if err == ErrNotFound {
+		return nil
+	}
+
+	ci := res.(*cacheItem)
+
+	l.remove(ci, ci.freqElement)
+	l.currentSize--
+	return l.cache.Delete(key)
+}
+
+// set sets a new key-value pair
+func (l *LFUNoTS) set(key string, value interface{}) error {
+	res, err := l.cache.Get(key)
+	if err != nil && err != ErrNotFound {
+		return err
+	}
+
+	if err == ErrNotFound {
+		//create new cache item
+		ci := newCacheItem(key, value)
+
+		// if cache size si reached to max size
+		// then first remove lfu item from the list
+		if l.currentSize >= l.size {
+			// then evict some data from head of linked list.
+			l.evict(l.frequencyList.Front())
+		}
+
+		l.cache.Set(key, ci)
+		l.incr(ci)
+
+	} else {
+		//update existing one
+		val := res.(*cacheItem)
+		val.v = value
+		l.cache.Set(key, val)
+		l.incr(res.(*cacheItem))
+	}
+
+	return nil
+}
+
+// entry holds the frequency node informations
+type entry struct {
+	// freqCount holds the frequency number
+	freqCount int
+
+	// itemCount holds the items how many exist in list
+	listEntry map[*cacheItem]struct{}
+}
+
+// incr increments the usage of cache items
+// incrementing will be used in 'Get' & 'Set' functions
+// whenever these functions are used, usage count of any key
+// will be increased
+func (l *LFUNoTS) incr(ci *cacheItem) {
+	var nextValue int
+	var nextPosition *list.Element
+	// update existing one
+	if ci.freqElement != nil {
+		nextValue = ci.freqElement.Value.(*entry).freqCount + 1
+		// replace the position of frequency element
+		nextPosition = ci.freqElement.Next()
+	} else {
+		// create new frequency element for cache item
+		// ci.freqElement is nil so next value of freq will be 1
+		nextValue = 1
+		// we created new element and its position will be head of linked list
+		nextPosition = l.frequencyList.Front()
+		l.currentSize++
+	}
+
+	// we need to check position first, otherwise it will panic if we try to fetch value of entry
+	if nextPosition == nil || nextPosition.Value.(*entry).freqCount != nextValue {
+		// create new entry node for linked list
+		entry := newEntry(nextValue)
+		if ci.freqElement == nil {
+			nextPosition = l.frequencyList.PushFront(entry)
+		} else {
+			nextPosition = l.frequencyList.InsertAfter(entry, ci.freqElement)
+		}
+	}
+
+	nextPosition.Value.(*entry).listEntry[ci] = struct{}{}
+	ci.freqElement = nextPosition
+
+	// we have moved the cache item to the next position,
+	// then we need to  remove old position of the cacheItem from the list
+	// then we deleted previous position of cacheItem
+	if ci.freqElement.Prev() != nil {
+		l.remove(ci, ci.freqElement.Prev())
+	}
+}
+
+// remove removes the cache item from the cache list
+// after deleting key from the list, if its linked list has no any item no longer
+// then that linked list elemnet will be removed from the list too
+func (l *LFUNoTS) remove(ci *cacheItem, position *list.Element) {
+	entry := position.Value.(*entry).listEntry
+	delete(entry, ci)
+	if len(entry) == 0 {
+		l.frequencyList.Remove(position)
+	}
+}
+
+// evict deletes the element from list with given linked list element
+func (l *LFUNoTS) evict(e *list.Element) error {
+	// ne need to return err if list element is already nil
+	if e == nil {
+		return nil
+	}
+
+	// remove the first item of the linked list
+	for entry := range e.Value.(*entry).listEntry {
+		l.cache.Delete(entry.k)
+		l.remove(entry, e)
+		l.currentSize--
+		break
+	}
+
+	return nil
+}
+
+// newEntry creates a new entry with frequency count
+func newEntry(freqCount int) *entry {
+	return &entry{
+		freqCount: freqCount,
+		listEntry: make(map[*cacheItem]struct{}),
+	}
+}
+
+// newCacheItem creates a new cache item with key and value
+func newCacheItem(key string, value interface{}) *cacheItem {
+	return &cacheItem{
+		k: key,
+		v: value,
+	}
+
+}

vendor/github.com/koding/cache/memory_nots.go

@@ -13,6 +13,12 @@ func NewMemoryNoTS() *MemoryNoTS {
 	}
 }
 
+// NewMemNoTSCache is a helper method to return a Cache interface, so callers
+// don't have to typecast
+func NewMemNoTSCache() Cache {
+	return NewMemoryNoTS()
+}
+
 // Get returns a value of a given key if it exists
 // and valid for the time being
 func (r *MemoryNoTS) Get(key string) (interface{}, error) {

vendor/github.com/koding/cache/memory_ttl.go

@@ -12,7 +12,7 @@ var zeroTTL = time.Duration(0)
 type MemoryTTL struct {
 	// Mutex is used for handling the concurrent
 	// read/write requests for cache
-	sync.Mutex
+	sync.RWMutex
 
 	// cache holds the cache data
 	cache *MemoryNoTS
@@ -23,8 +23,11 @@ type MemoryTTL struct {
 	// ttl is a duration for a cache key to expire
 	ttl time.Duration
 
-	// gcInterval is a duration for garbage collection
-	gcInterval time.Duration
+	// gcTicker controls gc intervals
+	gcTicker *time.Ticker
+
+	// done controls sweeping goroutine lifetime
+	done chan struct{}
 }
 
 // NewMemoryWithTTL creates an inmemory cache system
@@ -41,29 +44,71 @@ func NewMemoryWithTTL(ttl time.Duration) *MemoryTTL {
 
 // StartGC starts the garbage collection process in a go routine
 func (r *MemoryTTL) StartGC(gcInterval time.Duration) {
-	r.gcInterval = gcInterval
+	if gcInterval <= 0 {
+		return
+	}
+
+	ticker := time.NewTicker(gcInterval)
+	done := make(chan struct{})
+
+	r.Lock()
+	r.gcTicker = ticker
+	r.done = done
+	r.Unlock()
+
 	go func() {
-		for _ = range time.Tick(gcInterval) {
-			for key := range r.cache.items {
-				if !r.isValid(key) {
-					r.Delete(key)
+		for {
+			select {
+			case <-ticker.C:
+				now := time.Now()
+
+				r.Lock()
+				for key := range r.cache.items {
+					if !r.isValidTime(key, now) {
+						r.delete(key)
+					}
 				}
+				r.Unlock()
+			case <-done:
+				return
 			}
 		}
 	}()
 }
 
+// StopGC stops sweeping goroutine.
+func (r *MemoryTTL) StopGC() {
+	if r.gcTicker != nil {
+		r.Lock()
+		r.gcTicker.Stop()
+		r.gcTicker = nil
+		close(r.done)
+		r.done = nil
+		r.Unlock()
+	}
+}
+
 // Get returns a value of a given key if it exists
 // and valid for the time being
 func (r *MemoryTTL) Get(key string) (interface{}, error) {
-	r.Lock()
-	defer r.Unlock()
+	r.RLock()
 
-	if !r.isValid(key) {
-		r.delete(key)
-		return nil, ErrNotFound
+	for !r.isValid(key) {
+		r.RUnlock()
+		// Need write lock to delete key, so need to unlock, relock and recheck
+		r.Lock()
+		if !r.isValid(key) {
+			r.delete(key)
+			r.Unlock()
+			return nil, ErrNotFound
+		}
+		r.Unlock()
+		// Could become invalid again in this window
+		r.RLock()
 	}
 
+	defer r.RUnlock()
+
 	value, err := r.cache.Get(key)
 	if err != nil {
 		return nil, err
@@ -98,6 +143,10 @@ func (r *MemoryTTL) delete(key string) {
 }
 
 func (r *MemoryTTL) isValid(key string) bool {
+	return r.isValidTime(key, time.Now())
+}
+
+func (r *MemoryTTL) isValidTime(key string, t time.Time) bool {
 	setAt, ok := r.setAts[key]
 	if !ok {
 		return false
@@ -107,5 +156,5 @@ func (r *MemoryTTL) isValid(key string) bool {
 		return true
 	}
 
-	return setAt.Add(r.ttl).After(time.Now())
+	return setAt.Add(r.ttl).After(t)
 }

vendor/github.com/koding/cache/mongo_cache.go

@@ -0,0 +1,227 @@
+package cache
+
+import (
+	"fmt"
+	"sync"
+	"time"
+
+	mgo "gopkg.in/mgo.v2"
+)
+
+const (
+	defaultExpireDuration = time.Minute
+	defaultCollectionName = "jCache"
+	defaultGCInterval     = time.Minute
+	indexExpireAt         = "expireAt"
+)
+
+// MongoCache holds the cache values that will be stored in mongoDB
+type MongoCache struct {
+	// mongeSession specifies the mongoDB connection
+	mongeSession *mgo.Session
+
+	// CollectionName speficies the optional collection name for mongoDB
+	// if CollectionName is not set, then default value will be set
+	CollectionName string
+
+	// ttl is a duration for a cache key to expire
+	TTL time.Duration
+
+	// GCInterval specifies the time duration for garbage collector time interval
+	GCInterval time.Duration
+
+	// GCStart starts the garbage collector and deletes the
+	// expired keys from mongo with given time interval
+	GCStart bool
+
+	// gcTicker controls gc intervals
+	gcTicker *time.Ticker
+
+	// done controls sweeping goroutine lifetime
+	done chan struct{}
+
+	// Mutex is used for handling the concurrent
+	// read/write requests for cache
+	sync.RWMutex
+}
+
+// Option sets the options specified.
+type Option func(*MongoCache)
+
+// NewMongoCacheWithTTL creates a caching layer backed by mongo. TTL's are
+// managed either by a background cleaner or document is removed on the Get
+// operation. Mongo TTL indexes are not utilized since there can be multiple
+// systems using the same collection with different TTL values.
+//
+// The responsibility of stopping the GC process belongs to the user.
+//
+// Session is not closed while stopping the GC.
+//
+// This self-referential function satisfy you to avoid passing
+// nil value to the function as parameter
+// e.g (usage) :
+// configure with defaults, just call;
+// NewMongoCacheWithTTL(session)
+//
+// configure ttl duration with;
+// NewMongoCacheWithTTL(session, func(m *MongoCache) {
+// 		m.TTL = 2 * time.Minute
+// })
+// or
+// NewMongoCacheWithTTL(session, SetTTL(time.Minute * 2))
+//
+// configure collection name with;
+// NewMongoCacheWithTTL(session, func(m *MongoCache) {
+// 		m.CollectionName = "MongoCacheCollectionName"
+// })
+func NewMongoCacheWithTTL(session *mgo.Session, configs ...Option) *MongoCache {
+	if session == nil {
+		panic("session must be set")
+	}
+
+	mc := &MongoCache{
+		mongeSession:   session,
+		TTL:            defaultExpireDuration,
+		CollectionName: defaultCollectionName,
+		GCInterval:     defaultGCInterval,
+		GCStart:        false,
+	}
+
+	for _, configFunc := range configs {
+		configFunc(mc)
+	}
+
+	if mc.GCStart {
+		mc.StartGC(mc.GCInterval)
+	}
+
+	return mc
+}
+
+// MustEnsureIndexExpireAt ensures the expireAt index
+// usage:
+// NewMongoCacheWithTTL(mongoSession, MustEnsureIndexExpireAt())
+func MustEnsureIndexExpireAt() Option {
+	return func(m *MongoCache) {
+		if err := m.EnsureIndex(); err != nil {
+			panic(fmt.Sprintf("index must ensure %q", err))
+		}
+	}
+}
+
+// StartGC enables the garbage collector in MongoCache struct
+// usage:
+// NewMongoCacheWithTTL(mongoSession, StartGC())
+func StartGC() Option {
+	return func(m *MongoCache) {
+		m.GCStart = true
+	}
+}
+
+// SetTTL sets the ttl duration in MongoCache as option
+// usage:
+// NewMongoCacheWithTTL(mongoSession, SetTTL(time*Minute))
+func SetTTL(duration time.Duration) Option {
+	return func(m *MongoCache) {
+		m.TTL = duration
+	}
+}
+
+// SetGCInterval sets the garbage collector interval in MongoCache struct as option
+// usage:
+// NewMongoCacheWithTTL(mongoSession, SetGCInterval(time*Minute))
+func SetGCInterval(duration time.Duration) Option {
+	return func(m *MongoCache) {
+		m.GCInterval = duration
+	}
+}
+
+// SetCollectionName sets the collection name for mongoDB in MongoCache struct as option
+// usage:
+// NewMongoCacheWithTTL(mongoSession, SetCollectionName("mongoCollName"))
+func SetCollectionName(collName string) Option {
+	return func(m *MongoCache) {
+		m.CollectionName = collName
+	}
+}
+
+// Get returns a value of a given key if it exists
+func (m *MongoCache) Get(key string) (interface{}, error) {
+	data, err := m.get(key)
+	if err == mgo.ErrNotFound {
+		return nil, ErrNotFound
+	}
+
+	if err != nil {
+		return nil, err
+	}
+
+	return data.Value, nil
+}
+
+// Set will persist a value to the cache or override existing one with the new
+// one
+func (m *MongoCache) Set(key string, value interface{}) error {
+	return m.set(key, m.TTL, value)
+}
+
+// SetEx will persist a value to the cache or override existing one with the new
+// one with ttl duration
+func (m *MongoCache) SetEx(key string, duration time.Duration, value interface{}) error {
+	return m.set(key, duration, value)
+}
+
+// Delete deletes a given key if exists
+func (m *MongoCache) Delete(key string) error {
+	return m.delete(key)
+}
+
+// EnsureIndex ensures the index with expireAt key
+func (m *MongoCache) EnsureIndex() error {
+	query := func(c *mgo.Collection) error {
+		return c.EnsureIndexKey(indexExpireAt)
+	}
+
+	return m.run(m.CollectionName, query)
+}
+
+// StartGC starts the garbage collector with given time interval The
+// expired data will be checked & deleted with given interval time
+func (m *MongoCache) StartGC(gcInterval time.Duration) {
+	if gcInterval <= 0 {
+		return
+	}
+
+	ticker := time.NewTicker(gcInterval)
+	done := make(chan struct{})
+
+	m.Lock()
+	m.gcTicker = ticker
+	m.done = done
+	m.Unlock()
+
+	go func() {
+		for {
+			select {
+			case <-ticker.C:
+				m.Lock()
+				m.deleteExpiredKeys()
+				m.Unlock()
+			case <-done:
+				return
+			}
+		}
+	}()
+}
+
+// StopGC stops sweeping goroutine.
+func (m *MongoCache) StopGC() {
+	if m.gcTicker != nil {
+		m.Lock()
+		m.gcTicker.Stop()
+		m.gcTicker = nil
+		close(m.done)
+		m.done = nil
+		m.Unlock()
+	}
+}

vendor/github.com/koding/cache/mongo_model.go

@@ -0,0 +1,81 @@
+package cache
+
+import (
+	"time"
+
+	mgo "gopkg.in/mgo.v2"
+	"gopkg.in/mgo.v2/bson"
+)
+
+// Document holds the key-value pair for mongo cache
+type Document struct {
+	Key      string      `bson:"_id" json:"_id"`
+	Value    interface{} `bson:"value" json:"value"`
+	ExpireAt time.Time   `bson:"expireAt" json:"expireAt"`
+}
+
+// getKey fetches the key with its key
+func (m *MongoCache) get(key string) (*Document, error) {
+	keyValue := new(Document)
+
+	query := func(c *mgo.Collection) error {
+		return c.Find(bson.M{
+			"_id": key,
+			"expireAt": bson.M{
+				"$gt": time.Now().UTC(),
+			}}).One(&keyValue)
+	}
+
+	err := m.run(m.CollectionName, query)
+	if err != nil {
+		return nil, err
+	}
+
+	return keyValue, nil
+}
+
+func (m *MongoCache) set(key string, duration time.Duration, value interface{}) error {
+	update := bson.M{
+		"_id":      key,
+		"value":    value,
+		"expireAt": time.Now().Add(duration),
+	}
+
+	query := func(c *mgo.Collection) error {
+		_, err := c.UpsertId(key, update)
+		return err
+	}
+
+	return m.run(m.CollectionName, query)
+}
+
+// deleteKey removes the key-value from mongoDB
+func (m *MongoCache) delete(key string) error {
+	query := func(c *mgo.Collection) error {
+		err := c.RemoveId(key)
+		return err
+	}
+
+	return m.run(m.CollectionName, query)
+}
+
+func (m *MongoCache) deleteExpiredKeys() error {
+	var selector = bson.M{"expireAt": bson.M{
+		"$lte": time.Now().UTC(),
+	}}
+
+	query := func(c *mgo.Collection) error {
+		_, err := c.RemoveAll(selector)
+		return err
+	}
+
+	return m.run(m.CollectionName, query)
+}
+
+func (m *MongoCache) run(collection string, s func(*mgo.Collection) error) error {
+	session := m.mongeSession.Copy()
+	defer session.Close()
+
+	c := session.DB("").C(collection)
+	return s(c)
+}

vendor/github.com/koding/cache/sharded_cache.go

@@ -0,0 +1,18 @@
+package cache
+
+// ShardedCache is the contract for all of the sharded cache backends that are supported by
+// this package
+type ShardedCache interface {
+	// Get returns single item from the backend if the requested item is not
+	// found, returns NotFound err
+	Get(shardID, key string) (interface{}, error)
+
+	// Set sets a single item to the backend
+	Set(shardID, key string, value interface{}) error
+
+	// Delete deletes single item from backend
+	Delete(shardID, key string) error
+
+	// Deletes all items in that shard
+	DeleteShard(shardID string) error
+}

vendor/github.com/koding/cache/sharded_nots.go

@@ -0,0 +1,67 @@
+package cache
+
+// ShardedNoTS ; the concept behind this storage is that each cache entry is
+// associated with a tenantID and this enables fast purging for just that
+// tenantID
+type ShardedNoTS struct {
+	cache       map[string]Cache
+	itemCount   map[string]int
+	constructor func() Cache
+}
+
+// NewShardedNoTS inits ShardedNoTS struct
+func NewShardedNoTS(c func() Cache) *ShardedNoTS {
+	return &ShardedNoTS{
+		constructor: c,
+		cache:       make(map[string]Cache),
+		itemCount:   make(map[string]int),
+	}
+}
+
+// Get returns a value of a given key if it exists
+// and valid for the time being
+func (l *ShardedNoTS) Get(tenantID, key string) (interface{}, error) {
+	cache, ok := l.cache[tenantID]
+	if !ok {
+		return nil, ErrNotFound
+	}
+
+	return cache.Get(key)
+}
+
+// Set will persist a value to the cache or override existing one with the new
+// one
+func (l *ShardedNoTS) Set(tenantID, key string, val interface{}) error {
+	_, ok := l.cache[tenantID]
+	if !ok {
+		l.cache[tenantID] = l.constructor()
+		l.itemCount[tenantID] = 0
+	}
+
+	l.itemCount[tenantID]++
+	return l.cache[tenantID].Set(key, val)
+}
+
+// Delete deletes a given key
+func (l *ShardedNoTS) Delete(tenantID, key string) error {
+	_, ok := l.cache[tenantID]
+	if !ok {
+		return nil
+	}
+
+	l.itemCount[tenantID]--
+
+	if l.itemCount[tenantID] == 0 {
+		return l.DeleteShard(tenantID)
+	}
+
+	return l.cache[tenantID].Delete(key)
+}
+
+// DeleteShard deletes the keys inside from maps of cache & itemCount
+func (l *ShardedNoTS) DeleteShard(tenantID string) error {
+	delete(l.cache, tenantID)
+	delete(l.itemCount, tenantID)
+
+	return nil
+}

vendor/github.com/koding/cache/sharded_ttl.go

@@ -0,0 +1,148 @@
+package cache
+
+import (
+	"sync"
+	"time"
+)
+
+// ShardedTTL holds the required variables to compose an in memory sharded cache system
+// which also provides expiring key mechanism
+type ShardedTTL struct {
+	// Mutex is used for handling the concurrent
+	// read/write requests for cache
+	sync.Mutex
+
+	// cache holds the cache data
+	cache ShardedCache
+
+	// setAts holds the time that related item's set at, indexed by tenantID
+	setAts map[string]map[string]time.Time
+
+	// ttl is a duration for a cache key to expire
+	ttl time.Duration
+
+	// gcInterval is a duration for garbage collection
+	gcInterval time.Duration
+}
+
+// NewShardedCacheWithTTL creates a sharded cache system with TTL based on specified Cache constructor
+// Which everytime will return the true values about a cache hit
+// and never will leak memory
+// ttl is used for expiration of a key from cache
+func NewShardedCacheWithTTL(ttl time.Duration, f func() Cache) *ShardedTTL {
+	return &ShardedTTL{
+		cache:  NewShardedNoTS(f),
+		setAts: map[string]map[string]time.Time{},
+		ttl:    ttl,
+	}
+}
+
+// NewShardedWithTTL creates an in-memory sharded cache system
+// ttl is used for expiration of a key from cache
+func NewShardedWithTTL(ttl time.Duration) *ShardedTTL {
+	return NewShardedCacheWithTTL(ttl, NewMemNoTSCache)
+}
+
+// StartGC starts the garbage collection process in a go routine
+func (r *ShardedTTL) StartGC(gcInterval time.Duration) {
+	r.gcInterval = gcInterval
+	go func() {
+		for _ = range time.Tick(gcInterval) {
+			r.Lock()
+			for tenantID := range r.setAts {
+				for key := range r.setAts[tenantID] {
+					if !r.isValid(tenantID, key) {
+						r.delete(tenantID, key)
+					}
+				}
+			}
+			r.Unlock()
+		}
+	}()
+}
+
+// Get returns a value of a given key if it exists
+// and valid for the time being
+func (r *ShardedTTL) Get(tenantID, key string) (interface{}, error) {
+	r.Lock()
+	defer r.Unlock()
+
+	if !r.isValid(tenantID, key) {
+		r.delete(tenantID, key)
+		return nil, ErrNotFound
+	}
+
+	value, err := r.cache.Get(tenantID, key)
+	if err != nil {
+		return nil, err
+	}
+
+	return value, nil
+}
+
+// Set will persist a value to the cache or
+// override existing one with the new one
+func (r *ShardedTTL) Set(tenantID, key string, value interface{}) error {
+	r.Lock()
+	defer r.Unlock()
+
+	r.cache.Set(tenantID, key, value)
+	_, ok := r.setAts[tenantID]
+	if !ok {
+		r.setAts[tenantID] = make(map[string]time.Time)
+	}
+	r.setAts[tenantID][key] = time.Now()
+	return nil
+}
+
+// Delete deletes a given key if exists
+func (r *ShardedTTL) Delete(tenantID, key string) error {
+	r.Lock()
+	defer r.Unlock()
+
+	r.delete(tenantID, key)
+	return nil
+}
+
+func (r *ShardedTTL) delete(tenantID, key string) {
+	_, ok := r.setAts[tenantID]
+	if !ok {
+		return
+	}
+	r.cache.Delete(tenantID, key)
+	delete(r.setAts[tenantID], key)
+	if len(r.setAts[tenantID]) == 0 {
+		delete(r.setAts, tenantID)
+	}
+}
+
+func (r *ShardedTTL) isValid(tenantID, key string) bool {
+
+	_, ok := r.setAts[tenantID]
+	if !ok {
+		return false
+	}
+	setAt, ok := r.setAts[tenantID][key]
+	if !ok {
+		return false
+	}
+	if r.ttl == zeroTTL {
+		return true
+	}
+
+	return setAt.Add(r.ttl).After(time.Now())
+}
+
+// DeleteShard deletes with given tenantID without key
+func (r *ShardedTTL) DeleteShard(tenantID string) error {
+	r.Lock()
+	defer r.Unlock()
+
+	_, ok := r.setAts[tenantID]
+	if ok {
+		for key := range r.setAts[tenantID] {
+			r.delete(tenantID, key)
+		}
+	}
+	return nil
+}

vendor/gopkg.in/mgo.v2/.travis.yml

@@ -0,0 +1,45 @@
+language: go
+
+go_import_path: gopkg.in/mgo.v2
+
+addons:
+    apt:
+        packages:
+
+env:
+    global:
+        - BUCKET=https://niemeyer.s3.amazonaws.com
+    matrix:
+        - GO=1.4.1 MONGODB=x86_64-2.2.7
+        - GO=1.4.1 MONGODB=x86_64-2.4.14
+        - GO=1.4.1 MONGODB=x86_64-2.6.11
+        - GO=1.4.1 MONGODB=x86_64-3.0.9
+        - GO=1.4.1 MONGODB=x86_64-3.2.3-nojournal
+        - GO=1.5.3 MONGODB=x86_64-3.0.9
+        - GO=1.6   MONGODB=x86_64-3.0.9
+
+install:
+    - eval "$(gimme $GO)"
+
+    - wget $BUCKET/mongodb-linux-$MONGODB.tgz
+    - tar xzvf mongodb-linux-$MONGODB.tgz
+    - export PATH=$PWD/mongodb-linux-$MONGODB/bin:$PATH
+
+    - wget $BUCKET/daemontools.tar.gz
+    - tar xzvf daemontools.tar.gz
+    - export PATH=$PWD/daemontools:$PATH
+
+    - go get gopkg.in/check.v1
+    - go get gopkg.in/yaml.v2
+    - go get gopkg.in/tomb.v2
+
+before_script:
+    - export NOIPV6=1
+    - make startdb
+
+script:
+    - (cd bson && go test -check.v)
+    - go test -check.v -fast
+    - (cd txn && go test -check.v)
+
+# vim:sw=4:ts=4:et

vendor/gopkg.in/mgo.v2/LICENSE

@@ -0,0 +1,25 @@
+mgo - MongoDB driver for Go
+
+Copyright (c) 2010-2013 - Gustavo Niemeyer <gustavo@niemeyer.net>
+
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met: 
+
+1. Redistributions of source code must retain the above copyright notice, this
+   list of conditions and the following disclaimer. 
+2. Redistributions in binary form must reproduce the above copyright notice,
+   this list of conditions and the following disclaimer in the documentation
+   and/or other materials provided with the distribution. 
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/gopkg.in/mgo.v2/Makefile

@@ -0,0 +1,5 @@
+startdb:
+	@harness/setup.sh start
+
+stopdb:
+	@harness/setup.sh stop

vendor/gopkg.in/mgo.v2/README.md

@@ -0,0 +1,4 @@
+The MongoDB driver for Go
+-------------------------
+
+Please go to [http://labix.org/mgo](http://labix.org/mgo) for all project details.

vendor/gopkg.in/mgo.v2/auth.go

@@ -0,0 +1,467 @@
+// mgo - MongoDB driver for Go
+//
+// Copyright (c) 2010-2012 - Gustavo Niemeyer <gustavo@niemeyer.net>
+//
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this
+//    list of conditions and the following disclaimer.
+// 2. Redistributions in binary form must reproduce the above copyright notice,
+//    this list of conditions and the following disclaimer in the documentation
+//    and/or other materials provided with the distribution.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+// ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package mgo
+
+import (
+	"crypto/md5"
+	"crypto/sha1"
+	"encoding/hex"
+	"errors"
+	"fmt"
+	"sync"
+
+	"gopkg.in/mgo.v2/bson"
+	"gopkg.in/mgo.v2/internal/scram"
+)
+
+type authCmd struct {
+	Authenticate int
+
+	Nonce string
+	User  string
+	Key   string
+}
+
+type startSaslCmd struct {
+	StartSASL int `bson:"startSasl"`
+}
+
+type authResult struct {
+	ErrMsg string
+	Ok     bool
+}
+
+type getNonceCmd struct {
+	GetNonce int
+}
+
+type getNonceResult struct {
+	Nonce string
+	Err   string "$err"
+	Code  int
+}
+
+type logoutCmd struct {
+	Logout int
+}
+
+type saslCmd struct {
+	Start          int    `bson:"saslStart,omitempty"`
+	Continue       int    `bson:"saslContinue,omitempty"`
+	ConversationId int    `bson:"conversationId,omitempty"`
+	Mechanism      string `bson:"mechanism,omitempty"`
+	Payload        []byte
+}
+
+type saslResult struct {
+	Ok    bool `bson:"ok"`
+	NotOk bool `bson:"code"` // Server <= 2.3.2 returns ok=1 & code>0 on errors (WTF?)
+	Done  bool
+
+	ConversationId int `bson:"conversationId"`
+	Payload        []byte
+	ErrMsg         string
+}
+
+type saslStepper interface {
+	Step(serverData []byte) (clientData []byte, done bool, err error)
+	Close()
+}
+
+func (socket *mongoSocket) getNonce() (nonce string, err error) {
+	socket.Lock()
+	for socket.cachedNonce == "" && socket.dead == nil {
+		debugf("Socket %p to %s: waiting for nonce", socket, socket.addr)
+		socket.gotNonce.Wait()
+	}
+	if socket.cachedNonce == "mongos" {
+		socket.Unlock()
+		return "", errors.New("Can't authenticate with mongos; see http://j.mp/mongos-auth")
+	}
+	debugf("Socket %p to %s: got nonce", socket, socket.addr)
+	nonce, err = socket.cachedNonce, socket.dead
+	socket.cachedNonce = ""
+	socket.Unlock()
+	if err != nil {
+		nonce = ""
+	}
+	return
+}
+
+func (socket *mongoSocket) resetNonce() {
+	debugf("Socket %p to %s: requesting a new nonce", socket, socket.addr)
+	op := &queryOp{}
+	op.query = &getNonceCmd{GetNonce: 1}
+	op.collection = "admin.$cmd"
+	op.limit = -1
+	op.replyFunc = func(err error, reply *replyOp, docNum int, docData []byte) {
+		if err != nil {
+			socket.kill(errors.New("getNonce: "+err.Error()), true)
+			return
+		}
+		result := &getNonceResult{}
+		err = bson.Unmarshal(docData, &result)
+		if err != nil {
+			socket.kill(errors.New("Failed to unmarshal nonce: "+err.Error()), true)
+			return
+		}
+		debugf("Socket %p to %s: nonce unmarshalled: %#v", socket, socket.addr, result)
+		if result.Code == 13390 {
+			// mongos doesn't yet support auth (see http://j.mp/mongos-auth)
+			result.Nonce = "mongos"
+		} else if result.Nonce == "" {
+			var msg string
+			if result.Err != "" {
+				msg = fmt.Sprintf("Got an empty nonce: %s (%d)", result.Err, result.Code)
+			} else {
+				msg = "Got an empty nonce"
+			}
+			socket.kill(errors.New(msg), true)
+			return
+		}
+		socket.Lock()
+		if socket.cachedNonce != "" {
+			socket.Unlock()
+			panic("resetNonce: nonce already cached")
+		}
+		socket.cachedNonce = result.Nonce
+		socket.gotNonce.Signal()
+		socket.Unlock()
+	}
+	err := socket.Query(op)
+	if err != nil {
+		socket.kill(errors.New("resetNonce: "+err.Error()), true)
+	}
+}
+
+func (socket *mongoSocket) Login(cred Credential) error {
+	socket.Lock()
+	if cred.Mechanism == "" && socket.serverInfo.MaxWireVersion >= 3 {
+		cred.Mechanism = "SCRAM-SHA-1"
+	}
+	for _, sockCred := range socket.creds {
+		if sockCred == cred {
+			debugf("Socket %p to %s: login: db=%q user=%q (already logged in)", socket, socket.addr, cred.Source, cred.Username)
+			socket.Unlock()
+			return nil
+		}
+	}
+	if socket.dropLogout(cred) {
+		debugf("Socket %p to %s: login: db=%q user=%q (cached)", socket, socket.addr, cred.Source, cred.Username)
+		socket.creds = append(socket.creds, cred)
+		socket.Unlock()
+		return nil
+	}
+	socket.Unlock()
+
+	debugf("Socket %p to %s: login: db=%q user=%q", socket, socket.addr, cred.Source, cred.Username)
+
+	var err error
+	switch cred.Mechanism {
+	case "", "MONGODB-CR", "MONGO-CR": // Name changed to MONGODB-CR in SERVER-8501.
+		err = socket.loginClassic(cred)
+	case "PLAIN":
+		err = socket.loginPlain(cred)
+	case "MONGODB-X509":
+		err = socket.loginX509(cred)
+	default:
+		// Try SASL for everything else, if it is available.
+		err = socket.loginSASL(cred)
+	}
+
+	if err != nil {
+		debugf("Socket %p to %s: login error: %s", socket, socket.addr, err)
+	} else {
+		debugf("Socket %p to %s: login successful", socket, socket.addr)
+	}
+	return err
+}
+
+func (socket *mongoSocket) loginClassic(cred Credential) error {
+	// Note that this only works properly because this function is
+	// synchronous, which means the nonce won't get reset while we're
+	// using it and any other login requests will block waiting for a
+	// new nonce provided in the defer call below.
+	nonce, err := socket.getNonce()
+	if err != nil {
+		return err
+	}
+	defer socket.resetNonce()
+
+	psum := md5.New()
+	psum.Write([]byte(cred.Username + ":mongo:" + cred.Password))
+
+	ksum := md5.New()
+	ksum.Write([]byte(nonce + cred.Username))
+	ksum.Write([]byte(hex.EncodeToString(psum.Sum(nil))))
+
+	key := hex.EncodeToString(ksum.Sum(nil))
+
+	cmd := authCmd{Authenticate: 1, User: cred.Username, Nonce: nonce, Key: key}
+	res := authResult{}
+	return socket.loginRun(cred.Source, &cmd, &res, func() error {
+		if !res.Ok {
+			return errors.New(res.ErrMsg)
+		}
+		socket.Lock()
+		socket.dropAuth(cred.Source)
+		socket.creds = append(socket.creds, cred)
+		socket.Unlock()
+		return nil
+	})
+}
+
+type authX509Cmd struct {
+	Authenticate int
+	User         string
+	Mechanism    string
+}
+
+func (socket *mongoSocket) loginX509(cred Credential) error {
+	cmd := authX509Cmd{Authenticate: 1, User: cred.Username, Mechanism: "MONGODB-X509"}
+	res := authResult{}
+	return socket.loginRun(cred.Source, &cmd, &res, func() error {
+		if !res.Ok {
+			return errors.New(res.ErrMsg)
+		}
+		socket.Lock()
+		socket.dropAuth(cred.Source)
+		socket.creds = append(socket.creds, cred)
+		socket.Unlock()
+		return nil
+	})
+}
+
+func (socket *mongoSocket) loginPlain(cred Credential) error {
+	cmd := saslCmd{Start: 1, Mechanism: "PLAIN", Payload: []byte("\x00" + cred.Username + "\x00" + cred.Password)}
+	res := authResult{}
+	return socket.loginRun(cred.Source, &cmd, &res, func() error {
+		if !res.Ok {
+			return errors.New(res.ErrMsg)
+		}
+		socket.Lock()
+		socket.dropAuth(cred.Source)
+		socket.creds = append(socket.creds, cred)
+		socket.Unlock()
+		return nil
+	})
+}
+
+func (socket *mongoSocket) loginSASL(cred Credential) error {
+	var sasl saslStepper
+	var err error
+	if cred.Mechanism == "SCRAM-SHA-1" {
+		// SCRAM is handled without external libraries.
+		sasl = saslNewScram(cred)
+	} else if len(cred.ServiceHost) > 0 {
+		sasl, err = saslNew(cred, cred.ServiceHost)
+	} else {
+		sasl, err = saslNew(cred, socket.Server().Addr)
+	}
+	if err != nil {
+		return err
+	}
+	defer sasl.Close()
+
+	// The goal of this logic is to carry a locked socket until the
+	// local SASL step confirms the auth is valid; the socket needs to be
+	// locked so that concurrent action doesn't leave the socket in an
+	// auth state that doesn't reflect the operations that took place.
+	// As a simple case, imagine inverting login=>logout to logout=>login.
+	//
+	// The logic below works because the lock func isn't called concurrently.
+	locked := false
+	lock := func(b bool) {
+		if locked != b {
+			locked = b
+			if b {
+				socket.Lock()
+			} else {
+				socket.Unlock()
+			}
+		}
+	}
+
+	lock(true)
+	defer lock(false)
+
+	start := 1
+	cmd := saslCmd{}
+	res := saslResult{}
+	for {
+		payload, done, err := sasl.Step(res.Payload)
+		if err != nil {
+			return err
+		}
+		if done && res.Done {
+			socket.dropAuth(cred.Source)
+			socket.creds = append(socket.creds, cred)
+			break
+		}
+		lock(false)
+
+		cmd = saslCmd{
+			Start:          start,
+			Continue:       1 - start,
+			ConversationId: res.ConversationId,
+			Mechanism:      cred.Mechanism,
+			Payload:        payload,
+		}
+		start = 0
+		err = socket.loginRun(cred.Source, &cmd, &res, func() error {
+			// See the comment on lock for why this is necessary.
+			lock(true)
+			if !res.Ok || res.NotOk {
+				return fmt.Errorf("server returned error on SASL authentication step: %s", res.ErrMsg)
+			}
+			return nil
+		})
+		if err != nil {
+			return err
+		}
+		if done && res.Done {
+			socket.dropAuth(cred.Source)
+			socket.creds = append(socket.creds, cred)
+			break
+		}
+	}
+
+	return nil
+}
+
+func saslNewScram(cred Credential) *saslScram {
+	credsum := md5.New()
+	credsum.Write([]byte(cred.Username + ":mongo:" + cred.Password))
+	client := scram.NewClient(sha1.New, cred.Username, hex.EncodeToString(credsum.Sum(nil)))
+	return &saslScram{cred: cred, client: client}
+}
+
+type saslScram struct {
+	cred   Credential
+	client *scram.Client
+}
+
+func (s *saslScram) Close() {}
+
+func (s *saslScram) Step(serverData []byte) (clientData []byte, done bool, err error) {
+	more := s.client.Step(serverData)
+	return s.client.Out(), !more, s.client.Err()
+}
+
+func (socket *mongoSocket) loginRun(db string, query, result interface{}, f func() error) error {
+	var mutex sync.Mutex
+	var replyErr error
+	mutex.Lock()
+
+	op := queryOp{}
+	op.query = query
+	op.collection = db + ".$cmd"
+	op.limit = -1
+	op.replyFunc = func(err error, reply *replyOp, docNum int, docData []byte) {
+		defer mutex.Unlock()
+
+		if err != nil {
+			replyErr = err
+			return
+		}
+
+		err = bson.Unmarshal(docData, result)
+		if err != nil {
+			replyErr = err
+		} else {
+			// Must handle this within the read loop for the socket, so
+			// that concurrent login requests are properly ordered.
+			replyErr = f()
+		}
+	}
+
+	err := socket.Query(&op)
+	if err != nil {
+		return err
+	}
+	mutex.Lock() // Wait.
+	return replyErr
+}
+
+func (socket *mongoSocket) Logout(db string) {
+	socket.Lock()
+	cred, found := socket.dropAuth(db)
+	if found {
+		debugf("Socket %p to %s: logout: db=%q (flagged)", socket, socket.addr, db)
+		socket.logout = append(socket.logout, cred)
+	}
+	socket.Unlock()
+}
+
+func (socket *mongoSocket) LogoutAll() {
+	socket.Lock()
+	if l := len(socket.creds); l > 0 {
+		debugf("Socket %p to %s: logout all (flagged %d)", socket, socket.addr, l)
+		socket.logout = append(socket.logout, socket.creds...)
+		socket.creds = socket.creds[0:0]
+	}
+	socket.Unlock()
+}
+
+func (socket *mongoSocket) flushLogout() (ops []interface{}) {
+	socket.Lock()
+	if l := len(socket.logout); l > 0 {
+		debugf("Socket %p to %s: logout all (flushing %d)", socket, socket.addr, l)
+		for i := 0; i != l; i++ {
+			op := queryOp{}
+			op.query = &logoutCmd{1}
+			op.collection = socket.logout[i].Source + ".$cmd"
+			op.limit = -1
+			ops = append(ops, &op)
+		}
+		socket.logout = socket.logout[0:0]
+	}
+	socket.Unlock()
+	return
+}
+
+func (socket *mongoSocket) dropAuth(db string) (cred Credential, found bool) {
+	for i, sockCred := range socket.creds {
+		if sockCred.Source == db {
+			copy(socket.creds[i:], socket.creds[i+1:])
+			socket.creds = socket.creds[:len(socket.creds)-1]
+			return sockCred, true
+		}
+	}
+	return cred, false
+}
+
+func (socket *mongoSocket) dropLogout(cred Credential) (found bool) {
+	for i, sockCred := range socket.logout {
+		if sockCred == cred {
+			copy(socket.logout[i:], socket.logout[i+1:])
+			socket.logout = socket.logout[:len(socket.logout)-1]
+			return true
+		}
+	}
+	return false
+}

vendor/gopkg.in/mgo.v2/bson/LICENSE

@@ -0,0 +1,25 @@
+BSON library for Go
+
+Copyright (c) 2010-2012 - Gustavo Niemeyer <gustavo@niemeyer.net>
+
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met: 
+
+1. Redistributions of source code must retain the above copyright notice, this
+   list of conditions and the following disclaimer. 
+2. Redistributions in binary form must reproduce the above copyright notice,
+   this list of conditions and the following disclaimer in the documentation
+   and/or other materials provided with the distribution. 
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/gopkg.in/mgo.v2/bson/bson.go

@@ -0,0 +1,734 @@
+// BSON library for Go
+//
+// Copyright (c) 2010-2012 - Gustavo Niemeyer <gustavo@niemeyer.net>
+//
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this
+//    list of conditions and the following disclaimer.
+// 2. Redistributions in binary form must reproduce the above copyright notice,
+//    this list of conditions and the following disclaimer in the documentation
+//    and/or other materials provided with the distribution.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+// ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Package bson is an implementation of the BSON specification for Go:
+//
+//     http://bsonspec.org
+//
+// It was created as part of the mgo MongoDB driver for Go, but is standalone
+// and may be used on its own without the driver.
+package bson
+
+import (
+	"bytes"
+	"crypto/md5"
+	"encoding/binary"
+	"encoding/hex"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"os"
+	"reflect"
+	"runtime"
+	"strings"
+	"sync"
+	"sync/atomic"
+	"time"
+)
+
+// --------------------------------------------------------------------------
+// The public API.
+
+// A value implementing the bson.Getter interface will have its GetBSON
+// method called when the given value has to be marshalled, and the result
+// of this method will be marshaled in place of the actual object.
+//
+// If GetBSON returns return a non-nil error, the marshalling procedure
+// will stop and error out with the provided value.
+type Getter interface {
+	GetBSON() (interface{}, error)
+}
+
+// A value implementing the bson.Setter interface will receive the BSON
+// value via the SetBSON method during unmarshaling, and the object
+// itself will not be changed as usual.
+//
+// If setting the value works, the method should return nil or alternatively
+// bson.SetZero to set the respective field to its zero value (nil for
+// pointer types). If SetBSON returns a value of type bson.TypeError, the
+// BSON value will be omitted from a map or slice being decoded and the
+// unmarshalling will continue. If it returns any other non-nil error, the
+// unmarshalling procedure will stop and error out with the provided value.
+//
+// This interface is generally useful in pointer receivers, since the method
+// will want to change the receiver. A type field that implements the Setter
+// interface doesn't have to be a pointer, though.
+//
+// Unlike the usual behavior, unmarshalling onto a value that implements a
+// Setter interface will NOT reset the value to its zero state. This allows
+// the value to decide by itself how to be unmarshalled.
+//
+// For example:
+//
+//     type MyString string
+//
+//     func (s *MyString) SetBSON(raw bson.Raw) error {
+//         return raw.Unmarshal(s)
+//     }
+//
+type Setter interface {
+	SetBSON(raw Raw) error
+}
+
+// SetZero may be returned from a SetBSON method to have the value set to
+// its respective zero value. When used in pointer values, this will set the
+// field to nil rather than to the pre-allocated value.
+var SetZero = errors.New("set to zero")
+
+// M is a convenient alias for a map[string]interface{} map, useful for
+// dealing with BSON in a native way.  For instance:
+//
+//     bson.M{"a": 1, "b": true}
+//
+// There's no special handling for this type in addition to what's done anyway
+// for an equivalent map type.  Elements in the map will be dumped in an
+// undefined ordered. See also the bson.D type for an ordered alternative.
+type M map[string]interface{}
+
+// D represents a BSON document containing ordered elements. For example:
+//
+//     bson.D{{"a", 1}, {"b", true}}
+//
+// In some situations, such as when creating indexes for MongoDB, the order in
+// which the elements are defined is important.  If the order is not important,
+// using a map is generally more comfortable. See bson.M and bson.RawD.
+type D []DocElem
+
+// DocElem is an element of the bson.D document representation.
+type DocElem struct {
+	Name  string
+	Value interface{}
+}
+
+// Map returns a map out of the ordered element name/value pairs in d.
+func (d D) Map() (m M) {
+	m = make(M, len(d))
+	for _, item := range d {
+		m[item.Name] = item.Value
+	}
+	return m
+}
+
+// The Raw type represents raw unprocessed BSON documents and elements.
+// Kind is the kind of element as defined per the BSON specification, and
+// Data is the raw unprocessed data for the respective element.
+// Using this type it is possible to unmarshal or marshal values partially.
+//
+// Relevant documentation:
+//
+//     http://bsonspec.org/#/specification
+//
+type Raw struct {
+	Kind byte
+	Data []byte
+}
+
+// RawD represents a BSON document containing raw unprocessed elements.
+// This low-level representation may be useful when lazily processing
+// documents of uncertain content, or when manipulating the raw content
+// documents in general.
+type RawD []RawDocElem
+
+// See the RawD type.
+type RawDocElem struct {
+	Name  string
+	Value Raw
+}
+
+// ObjectId is a unique ID identifying a BSON value. It must be exactly 12 bytes
+// long. MongoDB objects by default have such a property set in their "_id"
+// property.
+//
+// http://www.mongodb.org/display/DOCS/Object+IDs
+type ObjectId string
+
+// ObjectIdHex returns an ObjectId from the provided hex representation.
+// Calling this function with an invalid hex representation will
+// cause a runtime panic. See the IsObjectIdHex function.
+func ObjectIdHex(s string) ObjectId {
+	d, err := hex.DecodeString(s)
+	if err != nil || len(d) != 12 {
+		panic(fmt.Sprintf("invalid input to ObjectIdHex: %q", s))
+	}
+	return ObjectId(d)
+}
+
+// IsObjectIdHex returns whether s is a valid hex representation of
+// an ObjectId. See the ObjectIdHex function.
+func IsObjectIdHex(s string) bool {
+	if len(s) != 24 {
+		return false
+	}
+	_, err := hex.DecodeString(s)
+	return err == nil
+}
+
+// objectIdCounter is atomically incremented when generating a new ObjectId
+// using NewObjectId() function. It's used as a counter part of an id.
+var objectIdCounter uint32 = readRandomUint32()
+
+// readRandomUint32 returns a random objectIdCounter.
+func readRandomUint32() uint32 {
+	// We've found systems hanging in this function due to lack of entropy.
+	// The randomness of these bytes is just preventing nearby clashes, so
+	// just look at the time.
+	return uint32(time.Now().UnixNano())
+}
+
+// machineId stores machine id generated once and used in subsequent calls
+// to NewObjectId function.
+var machineId = readMachineId()
+var processId = os.Getpid()
+
+// readMachineId generates and returns a machine id.
+// If this function fails to get the hostname it will cause a runtime error.
+func readMachineId() []byte {
+	var sum [3]byte
+	id := sum[:]
+	hostname, err1 := os.Hostname()
+	if err1 != nil {
+		n := uint32(time.Now().UnixNano())
+		sum[0] = byte(n >> 0)
+		sum[1] = byte(n >> 8)
+		sum[2] = byte(n >> 16)
+		return id
+	}
+	hw := md5.New()
+	hw.Write([]byte(hostname))
+	copy(id, hw.Sum(nil))
+	return id
+}
+
+// NewObjectId returns a new unique ObjectId.
+func NewObjectId() ObjectId {
+	var b [12]byte
+	// Timestamp, 4 bytes, big endian
+	binary.BigEndian.PutUint32(b[:], uint32(time.Now().Unix()))
+	// Machine, first 3 bytes of md5(hostname)
+	b[4] = machineId[0]
+	b[5] = machineId[1]
+	b[6] = machineId[2]
+	// Pid, 2 bytes, specs don't specify endianness, but we use big endian.
+	b[7] = byte(processId >> 8)
+	b[8] = byte(processId)
+	// Increment, 3 bytes, big endian
+	i := atomic.AddUint32(&objectIdCounter, 1)
+	b[9] = byte(i >> 16)
+	b[10] = byte(i >> 8)
+	b[11] = byte(i)
+	return ObjectId(b[:])
+}
+
+// NewObjectIdWithTime returns a dummy ObjectId with the timestamp part filled
+// with the provided number of seconds from epoch UTC, and all other parts
+// filled with zeroes. It's not safe to insert a document with an id generated
+// by this method, it is useful only for queries to find documents with ids
+// generated before or after the specified timestamp.
+func NewObjectIdWithTime(t time.Time) ObjectId {
+	var b [12]byte
+	binary.BigEndian.PutUint32(b[:4], uint32(t.Unix()))
+	return ObjectId(string(b[:]))
+}
+
+// String returns a hex string representation of the id.
+// Example: ObjectIdHex("4d88e15b60f486e428412dc9").
+func (id ObjectId) String() string {
+	return fmt.Sprintf(`ObjectIdHex("%x")`, string(id))
+}
+
+// Hex returns a hex representation of the ObjectId.
+func (id ObjectId) Hex() string {
+	return hex.EncodeToString([]byte(id))
+}
+
+// MarshalJSON turns a bson.ObjectId into a json.Marshaller.
+func (id ObjectId) MarshalJSON() ([]byte, error) {
+	return []byte(fmt.Sprintf(`"%x"`, string(id))), nil
+}
+
+var nullBytes = []byte("null")
+
+// UnmarshalJSON turns *bson.ObjectId into a json.Unmarshaller.
+func (id *ObjectId) UnmarshalJSON(data []byte) error {
+	if len(data) > 0 && (data[0] == '{' || data[0] == 'O') {
+		var v struct {
+			Id   json.RawMessage `json:"$oid"`
+			Func struct {
+				Id json.RawMessage
+			} `json:"$oidFunc"`
+		}
+		err := jdec(data, &v)
+		if err == nil {
+			if len(v.Id) > 0 {
+				data = []byte(v.Id)
+			} else {
+				data = []byte(v.Func.Id)
+			}
+		}
+	}
+	if len(data) == 2 && data[0] == '"' && data[1] == '"' || bytes.Equal(data, nullBytes) {
+		*id = ""
+		return nil
+	}
+	if len(data) != 26 || data[0] != '"' || data[25] != '"' {
+		return errors.New(fmt.Sprintf("invalid ObjectId in JSON: %s", string(data)))
+	}
+	var buf [12]byte
+	_, err := hex.Decode(buf[:], data[1:25])
+	if err != nil {
+		return errors.New(fmt.Sprintf("invalid ObjectId in JSON: %s (%s)", string(data), err))
+	}
+	*id = ObjectId(string(buf[:]))
+	return nil
+}
+
+// MarshalText turns bson.ObjectId into an encoding.TextMarshaler.
+func (id ObjectId) MarshalText() ([]byte, error) {
+	return []byte(fmt.Sprintf("%x", string(id))), nil
+}
+
+// UnmarshalText turns *bson.ObjectId into an encoding.TextUnmarshaler.
+func (id *ObjectId) UnmarshalText(data []byte) error {
+	if len(data) == 1 && data[0] == ' ' || len(data) == 0 {
+		*id = ""
+		return nil
+	}
+	if len(data) != 24 {
+		return fmt.Errorf("invalid ObjectId: %s", data)
+	}
+	var buf [12]byte
+	_, err := hex.Decode(buf[:], data[:])
+	if err != nil {
+		return fmt.Errorf("invalid ObjectId: %s (%s)", data, err)
+	}
+	*id = ObjectId(string(buf[:]))
+	return nil
+}
+
+// Valid returns true if id is valid. A valid id must contain exactly 12 bytes.
+func (id ObjectId) Valid() bool {
+	return len(id) == 12
+}
+
+// byteSlice returns byte slice of id from start to end.
+// Calling this function with an invalid id will cause a runtime panic.
+func (id ObjectId) byteSlice(start, end int) []byte {
+	if len(id) != 12 {
+		panic(fmt.Sprintf("invalid ObjectId: %q", string(id)))
+	}
+	return []byte(string(id)[start:end])
+}
+
+// Time returns the timestamp part of the id.
+// It's a runtime error to call this method with an invalid id.
+func (id ObjectId) Time() time.Time {
+	// First 4 bytes of ObjectId is 32-bit big-endian seconds from epoch.
+	secs := int64(binary.BigEndian.Uint32(id.byteSlice(0, 4)))
+	return time.Unix(secs, 0)
+}
+
+// Machine returns the 3-byte machine id part of the id.
+// It's a runtime error to call this method with an invalid id.
+func (id ObjectId) Machine() []byte {
+	return id.byteSlice(4, 7)
+}
+
+// Pid returns the process id part of the id.
+// It's a runtime error to call this method with an invalid id.
+func (id ObjectId) Pid() uint16 {
+	return binary.BigEndian.Uint16(id.byteSlice(7, 9))
+}
+
+// Counter returns the incrementing value part of the id.
+// It's a runtime error to call this method with an invalid id.
+func (id ObjectId) Counter() int32 {
+	b := id.byteSlice(9, 12)
+	// Counter is stored as big-endian 3-byte value
+	return int32(uint32(b[0])<<16 | uint32(b[1])<<8 | uint32(b[2]))
+}
+
+// The Symbol type is similar to a string and is used in languages with a
+// distinct symbol type.
+type Symbol string
+
+// Now returns the current time with millisecond precision. MongoDB stores
+// timestamps with the same precision, so a Time returned from this method
+// will not change after a roundtrip to the database. That's the only reason
+// why this function exists. Using the time.Now function also works fine
+// otherwise.
+func Now() time.Time {
+	return time.Unix(0, time.Now().UnixNano()/1e6*1e6)
+}
+
+// MongoTimestamp is a special internal type used by MongoDB that for some
+// strange reason has its own datatype defined in BSON.
+type MongoTimestamp int64
+
+type orderKey int64
+
+// MaxKey is a special value that compares higher than all other possible BSON
+// values in a MongoDB database.
+var MaxKey = orderKey(1<<63 - 1)
+
+// MinKey is a special value that compares lower than all other possible BSON
+// values in a MongoDB database.
+var MinKey = orderKey(-1 << 63)
+
+type undefined struct{}
+
+// Undefined represents the undefined BSON value.
+var Undefined undefined
+
+// Binary is a representation for non-standard binary values.  Any kind should
+// work, but the following are known as of this writing:
+//
+//   0x00 - Generic. This is decoded as []byte(data), not Binary{0x00, data}.
+//   0x01 - Function (!?)
+//   0x02 - Obsolete generic.
+//   0x03 - UUID
+//   0x05 - MD5
+//   0x80 - User defined.
+//
+type Binary struct {
+	Kind byte
+	Data []byte
+}
+
+// RegEx represents a regular expression.  The Options field may contain
+// individual characters defining the way in which the pattern should be
+// applied, and must be sorted. Valid options as of this writing are 'i' for
+// case insensitive matching, 'm' for multi-line matching, 'x' for verbose
+// mode, 'l' to make \w, \W, and similar be locale-dependent, 's' for dot-all
+// mode (a '.' matches everything), and 'u' to make \w, \W, and similar match
+// unicode. The value of the Options parameter is not verified before being
+// marshaled into the BSON format.
+type RegEx struct {
+	Pattern string
+	Options string
+}
+
+// JavaScript is a type that holds JavaScript code. If Scope is non-nil, it
+// will be marshaled as a mapping from identifiers to values that may be
+// used when evaluating the provided Code.
+type JavaScript struct {
+	Code  string
+	Scope interface{}
+}
+
+// DBPointer refers to a document id in a namespace.
+//
+// This type is deprecated in the BSON specification and should not be used
+// except for backwards compatibility with ancient applications.
+type DBPointer struct {
+	Namespace string
+	Id        ObjectId
+}
+
+const initialBufferSize = 64
+
+func handleErr(err *error) {
+	if r := recover(); r != nil {
+		if _, ok := r.(runtime.Error); ok {
+			panic(r)
+		} else if _, ok := r.(externalPanic); ok {
+			panic(r)
+		} else if s, ok := r.(string); ok {
+			*err = errors.New(s)
+		} else if e, ok := r.(error); ok {
+			*err = e
+		} else {
+			panic(r)
+		}
+	}
+}
+
+// Marshal serializes the in value, which may be a map or a struct value.
+// In the case of struct values, only exported fields will be serialized,
+// and the order of serialized fields will match that of the struct itself.
+// The lowercased field name is used as the key for each exported field,
+// but this behavior may be changed using the respective field tag.
+// The tag may also contain flags to tweak the marshalling behavior for
+// the field. The tag formats accepted are:
+//
+//     "[<key>][,<flag1>[,<flag2>]]"
+//
+//     `(...) bson:"[<key>][,<flag1>[,<flag2>]]" (...)`
+//
+// The following flags are currently supported:
+//
+//     omitempty  Only include the field if it's not set to the zero
+//                value for the type or to empty slices or maps.
+//
+//     minsize    Marshal an int64 value as an int32, if that's feasible
+//                while preserving the numeric value.
+//
+//     inline     Inline the field, which must be a struct or a map,
+//                causing all of its fields or keys to be processed as if
+//                they were part of the outer struct. For maps, keys must
+//                not conflict with the bson keys of other struct fields.
+//
+// Some examples:
+//
+//     type T struct {
+//         A bool
+//         B int    "myb"
+//         C string "myc,omitempty"
+//         D string `bson:",omitempty" json:"jsonkey"`
+//         E int64  ",minsize"
+//         F int64  "myf,omitempty,minsize"
+//     }
+//
+func Marshal(in interface{}) (out []byte, err error) {
+	defer handleErr(&err)
+	e := &encoder{make([]byte, 0, initialBufferSize)}
+	e.addDoc(reflect.ValueOf(in))
+	return e.out, nil
+}
+
+// Unmarshal deserializes data from in into the out value.  The out value
+// must be a map, a pointer to a struct, or a pointer to a bson.D value.
+// In the case of struct values, only exported fields will be deserialized.
+// The lowercased field name is used as the key for each exported field,
+// but this behavior may be changed using the respective field tag.
+// The tag may also contain flags to tweak the marshalling behavior for
+// the field. The tag formats accepted are:
+//
+//     "[<key>][,<flag1>[,<flag2>]]"
+//
+//     `(...) bson:"[<key>][,<flag1>[,<flag2>]]" (...)`
+//
+// The following flags are currently supported during unmarshal (see the
+// Marshal method for other flags):
+//
+//     inline     Inline the field, which must be a struct or a map.
+//                Inlined structs are handled as if its fields were part
+//                of the outer struct. An inlined map causes keys that do
+//                not match any other struct field to be inserted in the
+//                map rather than being discarded as usual.
+//
+// The target field or element types of out may not necessarily match
+// the BSON values of the provided data.  The following conversions are
+// made automatically:
+//
+// - Numeric types are converted if at least the integer part of the
+//   value would be preserved correctly
+// - Bools are converted to numeric types as 1 or 0
+// - Numeric types are converted to bools as true if not 0 or false otherwise
+// - Binary and string BSON data is converted to a string, array or byte slice
+//
+// If the value would not fit the type and cannot be converted, it's
+// silently skipped.
+//
+// Pointer values are initialized when necessary.
+func Unmarshal(in []byte, out interface{}) (err error) {
+	if raw, ok := out.(*Raw); ok {
+		raw.Kind = 3
+		raw.Data = in
+		return nil
+	}
+	defer handleErr(&err)
+	v := reflect.ValueOf(out)
+	switch v.Kind() {
+	case reflect.Ptr:
+		fallthrough
+	case reflect.Map:
+		d := newDecoder(in)
+		d.readDocTo(v)
+	case reflect.Struct:
+		return errors.New("Unmarshal can't deal with struct values. Use a pointer.")
+	default:
+		return errors.New("Unmarshal needs a map or a pointer to a struct.")
+	}
+	return nil
+}
+
+// Unmarshal deserializes raw into the out value.  If the out value type
+// is not compatible with raw, a *bson.TypeError is returned.
+//
+// See the Unmarshal function documentation for more details on the
+// unmarshalling process.
+func (raw Raw) Unmarshal(out interface{}) (err error) {
+	defer handleErr(&err)
+	v := reflect.ValueOf(out)
+	switch v.Kind() {
+	case reflect.Ptr:
+		v = v.Elem()
+		fallthrough
+	case reflect.Map:
+		d := newDecoder(raw.Data)
+		good := d.readElemTo(v, raw.Kind)
+		if !good {
+			return &TypeError{v.Type(), raw.Kind}
+		}
+	case reflect.Struct:
+		return errors.New("Raw Unmarshal can't deal with struct values. Use a pointer.")
+	default:
+		return errors.New("Raw Unmarshal needs a map or a valid pointer.")
+	}
+	return nil
+}
+
+type TypeError struct {
+	Type reflect.Type
+	Kind byte
+}
+
+func (e *TypeError) Error() string {
+	return fmt.Sprintf("BSON kind 0x%02x isn't compatible with type %s", e.Kind, e.Type.String())
+}
+
+// --------------------------------------------------------------------------
+// Maintain a mapping of keys to structure field indexes
+
+type structInfo struct {
+	FieldsMap  map[string]fieldInfo
+	FieldsList []fieldInfo
+	InlineMap  int
+	Zero       reflect.Value
+}
+
+type fieldInfo struct {
+	Key       string
+	Num       int
+	OmitEmpty bool
+	MinSize   bool
+	Inline    []int
+}
+
+var structMap = make(map[reflect.Type]*structInfo)
+var structMapMutex sync.RWMutex
+
+type externalPanic string
+
+func (e externalPanic) String() string {
+	return string(e)
+}
+
+func getStructInfo(st reflect.Type) (*structInfo, error) {
+	structMapMutex.RLock()
+	sinfo, found := structMap[st]
+	structMapMutex.RUnlock()
+	if found {
+		return sinfo, nil
+	}
+	n := st.NumField()
+	fieldsMap := make(map[string]fieldInfo)
+	fieldsList := make([]fieldInfo, 0, n)
+	inlineMap := -1
+	for i := 0; i != n; i++ {
+		field := st.Field(i)
+		if field.PkgPath != "" && !field.Anonymous {
+			continue // Private field
+		}
+
+		info := fieldInfo{Num: i}
+
+		tag := field.Tag.Get("bson")
+		if tag == "" && strings.Index(string(field.Tag), ":") < 0 {
+			tag = string(field.Tag)
+		}
+		if tag == "-" {
+			continue
+		}
+
+		inline := false
+		fields := strings.Split(tag, ",")
+		if len(fields) > 1 {
+			for _, flag := range fields[1:] {
+				switch flag {
+				case "omitempty":
+					info.OmitEmpty = true
+				case "minsize":
+					info.MinSize = true
+				case "inline":
+					inline = true
+				default:
+					msg := fmt.Sprintf("Unsupported flag %q in tag %q of type %s", flag, tag, st)
+					panic(externalPanic(msg))
+				}
+			}
+			tag = fields[0]
+		}
+
+		if inline {
+			switch field.Type.Kind() {
+			case reflect.Map:
+				if inlineMap >= 0 {
+					return nil, errors.New("Multiple ,inline maps in struct " + st.String())
+				}
+				if field.Type.Key() != reflect.TypeOf("") {
+					return nil, errors.New("Option ,inline needs a map with string keys in struct " + st.String())
+				}
+				inlineMap = info.Num
+			case reflect.Struct:
+				sinfo, err := getStructInfo(field.Type)
+				if err != nil {
+					return nil, err
+				}
+				for _, finfo := range sinfo.FieldsList {
+					if _, found := fieldsMap[finfo.Key]; found {
+						msg := "Duplicated key '" + finfo.Key + "' in struct " + st.String()
+						return nil, errors.New(msg)
+					}
+					if finfo.Inline == nil {
+						finfo.Inline = []int{i, finfo.Num}
+					} else {
+						finfo.Inline = append([]int{i}, finfo.Inline...)
+					}
+					fieldsMap[finfo.Key] = finfo
+					fieldsList = append(fieldsList, finfo)
+				}
+			default:
+				panic("Option ,inline needs a struct value or map field")
+			}
+			continue
+		}
+
+		if tag != "" {
+			info.Key = tag
+		} else {
+			info.Key = strings.ToLower(field.Name)
+		}
+
+		if _, found = fieldsMap[info.Key]; found {
+			msg := "Duplicated key '" + info.Key + "' in struct " + st.String()
+			return nil, errors.New(msg)
+		}
+
+		fieldsList = append(fieldsList, info)
+		fieldsMap[info.Key] = info
+	}
+	sinfo = &structInfo{
+		fieldsMap,
+		fieldsList,
+		inlineMap,
+		reflect.New(st).Elem(),
+	}
+	structMapMutex.Lock()
+	structMap[st] = sinfo
+	structMapMutex.Unlock()
+	return sinfo, nil
+}

vendor/gopkg.in/mgo.v2/bson/decimal.go

@@ -0,0 +1,310 @@
+// BSON library for Go
+//
+// Copyright (c) 2010-2012 - Gustavo Niemeyer <gustavo@niemeyer.net>
+//
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this
+//    list of conditions and the following disclaimer.
+// 2. Redistributions in binary form must reproduce the above copyright notice,
+//    this list of conditions and the following disclaimer in the documentation
+//    and/or other materials provided with the distribution.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+// ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package bson
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+// Decimal128 holds decimal128 BSON values.
+type Decimal128 struct {
+	h, l uint64
+}
+
+func (d Decimal128) String() string {
+	var pos int     // positive sign
+	var e int       // exponent
+	var h, l uint64 // significand high/low
+
+	if d.h>>63&1 == 0 {
+		pos = 1
+	}
+
+	switch d.h >> 58 & (1<<5 - 1) {
+	case 0x1F:
+		return "NaN"
+	case 0x1E:
+		return "-Inf"[pos:]
+	}
+
+	l = d.l
+	if d.h>>61&3 == 3 {
+		// Bits: 1*sign 2*ignored 14*exponent 111*significand.
+		// Implicit 0b100 prefix in significand.
+		e = int(d.h>>47&(1<<14-1)) - 6176
+		//h = 4<<47 | d.h&(1<<47-1)
+		// Spec says all of these values are out of range.
+		h, l = 0, 0
+	} else {
+		// Bits: 1*sign 14*exponent 113*significand
+		e = int(d.h>>49&(1<<14-1)) - 6176
+		h = d.h & (1<<49 - 1)
+	}
+
+	// Would be handled by the logic below, but that's trivial and common.
+	if h == 0 && l == 0 && e == 0 {
+		return "-0"[pos:]
+	}
+
+	var repr [48]byte // Loop 5 times over 9 digits plus dot, negative sign, and leading zero.
+	var last = len(repr)
+	var i = len(repr)
+	var dot = len(repr) + e
+	var rem uint32
+Loop:
+	for d9 := 0; d9 < 5; d9++ {
+		h, l, rem = divmod(h, l, 1e9)
+		for d1 := 0; d1 < 9; d1++ {
+			// Handle "-0.0", "0.00123400", "-1.00E-6", "1.050E+3", etc.
+			if i < len(repr) && (dot == i || l == 0 && h == 0 && rem > 0 && rem < 10 && (dot < i-6 || e > 0)) {
+				e += len(repr) - i
+				i--
+				repr[i] = '.'
+				last = i - 1
+				dot = len(repr) // Unmark.
+			}
+			c := '0' + byte(rem%10)
+			rem /= 10
+			i--
+			repr[i] = c
+			// Handle "0E+3", "1E+3", etc.
+			if l == 0 && h == 0 && rem == 0 && i == len(repr)-1 && (dot < i-5 || e > 0) {
+				last = i
+				break Loop
+			}
+			if c != '0' {
+				last = i
+			}
+			// Break early. Works without it, but why.
+			if dot > i && l == 0 && h == 0 && rem == 0 {
+				break Loop
+			}
+		}
+	}
+	repr[last-1] = '-'
+	last--
+
+	if e > 0 {
+		return string(repr[last+pos:]) + "E+" + strconv.Itoa(e)
+	}
+	if e < 0 {
+		return string(repr[last+pos:]) + "E" + strconv.Itoa(e)
+	}
+	return string(repr[last+pos:])
+}
+
+func divmod(h, l uint64, div uint32) (qh, ql uint64, rem uint32) {
+	div64 := uint64(div)
+	a := h >> 32
+	aq := a / div64
+	ar := a % div64
+	b := ar<<32 + h&(1<<32-1)
+	bq := b / div64
+	br := b % div64
+	c := br<<32 + l>>32
+	cq := c / div64
+	cr := c % div64
+	d := cr<<32 + l&(1<<32-1)
+	dq := d / div64
+	dr := d % div64
+	return (aq<<32 | bq), (cq<<32 | dq), uint32(dr)
+}
+
+var dNaN = Decimal128{0x1F << 58, 0}
+var dPosInf = Decimal128{0x1E << 58, 0}
+var dNegInf = Decimal128{0x3E << 58, 0}
+
+func dErr(s string) (Decimal128, error) {
+	return dNaN, fmt.Errorf("cannot parse %q as a decimal128", s)
+}
+
+func ParseDecimal128(s string) (Decimal128, error) {
+	orig := s
+	if s == "" {
+		return dErr(orig)
+	}
+	neg := s[0] == '-'
+	if neg || s[0] == '+' {
+		s = s[1:]
+	}
+
+	if (len(s) == 3 || len(s) == 8) && (s[0] == 'N' || s[0] == 'n' || s[0] == 'I' || s[0] == 'i') {
+		if s == "NaN" || s == "nan" || strings.EqualFold(s, "nan") {
+			return dNaN, nil
+		}
+		if s == "Inf" || s == "inf" || strings.EqualFold(s, "inf") || strings.EqualFold(s, "infinity") {
+			if neg {
+				return dNegInf, nil
+			}
+			return dPosInf, nil
+		}
+		return dErr(orig)
+	}
+
+	var h, l uint64
+	var e int
+
+	var add, ovr uint32
+	var mul uint32 = 1
+	var dot = -1
+	var digits = 0
+	var i = 0
+	for i < len(s) {
+		c := s[i]
+		if mul == 1e9 {
+			h, l, ovr = muladd(h, l, mul, add)
+			mul, add = 1, 0
+			if ovr > 0 || h&((1<<15-1)<<49) > 0 {
+				return dErr(orig)
+			}
+		}
+		if c >= '0' && c <= '9' {
+			i++
+			if c > '0' || digits > 0 {
+				digits++
+			}
+			if digits > 34 {
+				if c == '0' {
+					// Exact rounding.
+					e++
+					continue
+				}
+				return dErr(orig)
+			}
+			mul *= 10
+			add *= 10
+			add += uint32(c - '0')
+			continue
+		}
+		if c == '.' {
+			i++
+			if dot >= 0 || i == 1 && len(s) == 1 {
+				return dErr(orig)
+			}
+			if i == len(s) {
+				break
+			}
+			if s[i] < '0' || s[i] > '9' || e > 0 {
+				return dErr(orig)
+			}
+			dot = i
+			continue
+		}
+		break
+	}
+	if i == 0 {
+		return dErr(orig)
+	}
+	if mul > 1 {
+		h, l, ovr = muladd(h, l, mul, add)
+		if ovr > 0 || h&((1<<15-1)<<49) > 0 {
+			return dErr(orig)
+		}
+	}
+	if dot >= 0 {
+		e += dot - i
+	}
+	if i+1 < len(s) && (s[i] == 'E' || s[i] == 'e') {
+		i++
+		eneg := s[i] == '-'
+		if eneg || s[i] == '+' {
+			i++
+			if i == len(s) {
+				return dErr(orig)
+			}
+		}
+		n := 0
+		for i < len(s) && n < 1e4 {
+			c := s[i]
+			i++
+			if c < '0' || c > '9' {
+				return dErr(orig)
+			}
+			n *= 10
+			n += int(c - '0')
+		}
+		if eneg {
+			n = -n
+		}
+		e += n
+		for e < -6176 {
+			// Subnormal.
+			var div uint32 = 1
+			for div < 1e9 && e < -6176 {
+				div *= 10
+				e++
+			}
+			var rem uint32
+			h, l, rem = divmod(h, l, div)
+			if rem > 0 {
+				return dErr(orig)
+			}
+		}
+		for e > 6111 {
+			// Clamped.
+			var mul uint32 = 1
+			for mul < 1e9 && e > 6111 {
+				mul *= 10
+				e--
+			}
+			h, l, ovr = muladd(h, l, mul, 0)
+			if ovr > 0 || h&((1<<15-1)<<49) > 0 {
+				return dErr(orig)
+			}
+		}
+		if e < -6176 || e > 6111 {
+			return dErr(orig)
+		}
+	}
+
+	if i < len(s) {
+		return dErr(orig)
+	}
+
+	h |= uint64(e+6176) & uint64(1<<14-1) << 49
+	if neg {
+		h |= 1 << 63
+	}
+	return Decimal128{h, l}, nil
+}
+
+func muladd(h, l uint64, mul uint32, add uint32) (resh, resl uint64, overflow uint32) {
+	mul64 := uint64(mul)
+	a := mul64 * (l & (1<<32 - 1))
+	b := a>>32 + mul64*(l>>32)
+	c := b>>32 + mul64*(h&(1<<32-1))
+	d := c>>32 + mul64*(h>>32)
+
+	a = a&(1<<32-1) + uint64(add)
+	b = b&(1<<32-1) + a>>32
+	c = c&(1<<32-1) + b>>32
+	d = d&(1<<32-1) + c>>32
+
+	return (d<<32 | c&(1<<32-1)), (b<<32 | a&(1<<32-1)), uint32(d >> 32)
+}

vendor/gopkg.in/mgo.v2/bson/decode.go

@@ -0,0 +1,849 @@
+// BSON library for Go
+//
+// Copyright (c) 2010-2012 - Gustavo Niemeyer <gustavo@niemeyer.net>
+//
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this
+//    list of conditions and the following disclaimer.
+// 2. Redistributions in binary form must reproduce the above copyright notice,
+//    this list of conditions and the following disclaimer in the documentation
+//    and/or other materials provided with the distribution.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+// ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+// gobson - BSON library for Go.
+
+package bson
+
+import (
+	"fmt"
+	"math"
+	"net/url"
+	"reflect"
+	"strconv"
+	"sync"
+	"time"
+)
+
+type decoder struct {
+	in      []byte
+	i       int
+	docType reflect.Type
+}
+
+var typeM = reflect.TypeOf(M{})
+
+func newDecoder(in []byte) *decoder {
+	return &decoder{in, 0, typeM}
+}
+
+// --------------------------------------------------------------------------
+// Some helper functions.
+
+func corrupted() {
+	panic("Document is corrupted")
+}
+
+func settableValueOf(i interface{}) reflect.Value {
+	v := reflect.ValueOf(i)
+	sv := reflect.New(v.Type()).Elem()
+	sv.Set(v)
+	return sv
+}
+
+// --------------------------------------------------------------------------
+// Unmarshaling of documents.
+
+const (
+	setterUnknown = iota
+	setterNone
+	setterType
+	setterAddr
+)
+
+var setterStyles map[reflect.Type]int
+var setterIface reflect.Type
+var setterMutex sync.RWMutex
+
+func init() {
+	var iface Setter
+	setterIface = reflect.TypeOf(&iface).Elem()
+	setterStyles = make(map[reflect.Type]int)
+}
+
+func setterStyle(outt reflect.Type) int {
+	setterMutex.RLock()
+	style := setterStyles[outt]
+	setterMutex.RUnlock()
+	if style == setterUnknown {
+		setterMutex.Lock()
+		defer setterMutex.Unlock()
+		if outt.Implements(setterIface) {
+			setterStyles[outt] = setterType
+		} else if reflect.PtrTo(outt).Implements(setterIface) {
+			setterStyles[outt] = setterAddr
+		} else {
+			setterStyles[outt] = setterNone
+		}
+		style = setterStyles[outt]
+	}
+	return style
+}
+
+func getSetter(outt reflect.Type, out reflect.Value) Setter {
+	style := setterStyle(outt)
+	if style == setterNone {
+		return nil
+	}
+	if style == setterAddr {
+		if !out.CanAddr() {
+			return nil
+		}
+		out = out.Addr()
+	} else if outt.Kind() == reflect.Ptr && out.IsNil() {
+		out.Set(reflect.New(outt.Elem()))
+	}
+	return out.Interface().(Setter)
+}
+
+func clearMap(m reflect.Value) {
+	var none reflect.Value
+	for _, k := range m.MapKeys() {
+		m.SetMapIndex(k, none)
+	}
+}
+
+func (d *decoder) readDocTo(out reflect.Value) {
+	var elemType reflect.Type
+	outt := out.Type()
+	outk := outt.Kind()
+
+	for {
+		if outk == reflect.Ptr && out.IsNil() {
+			out.Set(reflect.New(outt.Elem()))
+		}
+		if setter := getSetter(outt, out); setter != nil {
+			var raw Raw
+			d.readDocTo(reflect.ValueOf(&raw))
+			err := setter.SetBSON(raw)
+			if _, ok := err.(*TypeError); err != nil && !ok {
+				panic(err)
+			}
+			return
+		}
+		if outk == reflect.Ptr {
+			out = out.Elem()
+			outt = out.Type()
+			outk = out.Kind()
+			continue
+		}
+		break
+	}
+
+	var fieldsMap map[string]fieldInfo
+	var inlineMap reflect.Value
+	start := d.i
+
+	origout := out
+	if outk == reflect.Interface {
+		if d.docType.Kind() == reflect.Map {
+			mv := reflect.MakeMap(d.docType)
+			out.Set(mv)
+			out = mv
+		} else {
+			dv := reflect.New(d.docType).Elem()
+			out.Set(dv)
+			out = dv
+		}
+		outt = out.Type()
+		outk = outt.Kind()
+	}
+
+	docType := d.docType
+	keyType := typeString
+	convertKey := false
+	switch outk {
+	case reflect.Map:
+		keyType = outt.Key()
+		if keyType.Kind() != reflect.String {
+			panic("BSON map must have string keys. Got: " + outt.String())
+		}
+		if keyType != typeString {
+			convertKey = true
+		}
+		elemType = outt.Elem()
+		if elemType == typeIface {
+			d.docType = outt
+		}
+		if out.IsNil() {
+			out.Set(reflect.MakeMap(out.Type()))
+		} else if out.Len() > 0 {
+			clearMap(out)
+		}
+	case reflect.Struct:
+		if outt != typeRaw {
+			sinfo, err := getStructInfo(out.Type())
+			if err != nil {
+				panic(err)
+			}
+			fieldsMap = sinfo.FieldsMap
+			out.Set(sinfo.Zero)
+			if sinfo.InlineMap != -1 {
+				inlineMap = out.Field(sinfo.InlineMap)
+				if !inlineMap.IsNil() && inlineMap.Len() > 0 {
+					clearMap(inlineMap)
+				}
+				elemType = inlineMap.Type().Elem()
+				if elemType == typeIface {
+					d.docType = inlineMap.Type()
+				}
+			}
+		}
+	case reflect.Slice:
+		switch outt.Elem() {
+		case typeDocElem:
+			origout.Set(d.readDocElems(outt))
+			return
+		case typeRawDocElem:
+			origout.Set(d.readRawDocElems(outt))
+			return
+		}
+		fallthrough
+	default:
+		panic("Unsupported document type for unmarshalling: " + out.Type().String())
+	}
+
+	end := int(d.readInt32())
+	end += d.i - 4
+	if end <= d.i || end > len(d.in) || d.in[end-1] != '\x00' {
+		corrupted()
+	}
+	for d.in[d.i] != '\x00' {
+		kind := d.readByte()
+		name := d.readCStr()
+		if d.i >= end {
+			corrupted()
+		}
+
+		switch outk {
+		case reflect.Map:
+			e := reflect.New(elemType).Elem()
+			if d.readElemTo(e, kind) {
+				k := reflect.ValueOf(name)
+				if convertKey {
+					k = k.Convert(keyType)
+				}
+				out.SetMapIndex(k, e)
+			}
+		case reflect.Struct:
+			if outt == typeRaw {
+				d.dropElem(kind)
+			} else {
+				if info, ok := fieldsMap[name]; ok {
+					if info.Inline == nil {
+						d.readElemTo(out.Field(info.Num), kind)
+					} else {
+						d.readElemTo(out.FieldByIndex(info.Inline), kind)
+					}
+				} else if inlineMap.IsValid() {
+					if inlineMap.IsNil() {
+						inlineMap.Set(reflect.MakeMap(inlineMap.Type()))
+					}
+					e := reflect.New(elemType).Elem()
+					if d.readElemTo(e, kind) {
+						inlineMap.SetMapIndex(reflect.ValueOf(name), e)
+					}
+				} else {
+					d.dropElem(kind)
+				}
+			}
+		case reflect.Slice:
+		}
+
+		if d.i >= end {
+			corrupted()
+		}
+	}
+	d.i++ // '\x00'
+	if d.i != end {
+		corrupted()
+	}
+	d.docType = docType
+
+	if outt == typeRaw {
+		out.Set(reflect.ValueOf(Raw{0x03, d.in[start:d.i]}))
+	}
+}
+
+func (d *decoder) readArrayDocTo(out reflect.Value) {
+	end := int(d.readInt32())
+	end += d.i - 4
+	if end <= d.i || end > len(d.in) || d.in[end-1] != '\x00' {
+		corrupted()
+	}
+	i := 0
+	l := out.Len()
+	for d.in[d.i] != '\x00' {
+		if i >= l {
+			panic("Length mismatch on array field")
+		}
+		kind := d.readByte()
+		for d.i < end && d.in[d.i] != '\x00' {
+			d.i++
+		}
+		if d.i >= end {
+			corrupted()
+		}
+		d.i++
+		d.readElemTo(out.Index(i), kind)
+		if d.i >= end {
+			corrupted()
+		}
+		i++
+	}
+	if i != l {
+		panic("Length mismatch on array field")
+	}
+	d.i++ // '\x00'
+	if d.i != end {
+		corrupted()
+	}
+}
+
+func (d *decoder) readSliceDoc(t reflect.Type) interface{} {
+	tmp := make([]reflect.Value, 0, 8)
+	elemType := t.Elem()
+	if elemType == typeRawDocElem {
+		d.dropElem(0x04)
+		return reflect.Zero(t).Interface()
+	}
+
+	end := int(d.readInt32())
+	end += d.i - 4
+	if end <= d.i || end > len(d.in) || d.in[end-1] != '\x00' {
+		corrupted()
+	}
+	for d.in[d.i] != '\x00' {
+		kind := d.readByte()
+		for d.i < end && d.in[d.i] != '\x00' {
+			d.i++
+		}
+		if d.i >= end {
+			corrupted()
+		}
+		d.i++
+		e := reflect.New(elemType).Elem()
+		if d.readElemTo(e, kind) {
+			tmp = append(tmp, e)
+		}
+		if d.i >= end {
+			corrupted()
+		}
+	}
+	d.i++ // '\x00'
+	if d.i != end {
+		corrupted()
+	}
+
+	n := len(tmp)
+	slice := reflect.MakeSlice(t, n, n)
+	for i := 0; i != n; i++ {
+		slice.Index(i).Set(tmp[i])
+	}
+	return slice.Interface()
+}
+
+var typeSlice = reflect.TypeOf([]interface{}{})
+var typeIface = typeSlice.Elem()
+
+func (d *decoder) readDocElems(typ reflect.Type) reflect.Value {
+	docType := d.docType
+	d.docType = typ
+	slice := make([]DocElem, 0, 8)
+	d.readDocWith(func(kind byte, name string) {
+		e := DocElem{Name: name}
+		v := reflect.ValueOf(&e.Value)
+		if d.readElemTo(v.Elem(), kind) {
+			slice = append(slice, e)
+		}
+	})
+	slicev := reflect.New(typ).Elem()
+	slicev.Set(reflect.ValueOf(slice))
+	d.docType = docType
+	return slicev
+}
+
+func (d *decoder) readRawDocElems(typ reflect.Type) reflect.Value {
+	docType := d.docType
+	d.docType = typ
+	slice := make([]RawDocElem, 0, 8)
+	d.readDocWith(func(kind byte, name string) {
+		e := RawDocElem{Name: name}
+		v := reflect.ValueOf(&e.Value)
+		if d.readElemTo(v.Elem(), kind) {
+			slice = append(slice, e)
+		}
+	})
+	slicev := reflect.New(typ).Elem()
+	slicev.Set(reflect.ValueOf(slice))
+	d.docType = docType
+	return slicev
+}
+
+func (d *decoder) readDocWith(f func(kind byte, name string)) {
+	end := int(d.readInt32())
+	end += d.i - 4
+	if end <= d.i || end > len(d.in) || d.in[end-1] != '\x00' {
+		corrupted()
+	}
+	for d.in[d.i] != '\x00' {
+		kind := d.readByte()
+		name := d.readCStr()
+		if d.i >= end {
+			corrupted()
+		}
+		f(kind, name)
+		if d.i >= end {
+			corrupted()
+		}
+	}
+	d.i++ // '\x00'
+	if d.i != end {
+		corrupted()
+	}
+}
+
+// --------------------------------------------------------------------------
+// Unmarshaling of individual elements within a document.
+
+var blackHole = settableValueOf(struct{}{})
+
+func (d *decoder) dropElem(kind byte) {
+	d.readElemTo(blackHole, kind)
+}
+
+// Attempt to decode an element from the document and put it into out.
+// If the types are not compatible, the returned ok value will be
+// false and out will be unchanged.
+func (d *decoder) readElemTo(out reflect.Value, kind byte) (good bool) {
+
+	start := d.i
+
+	if kind == 0x03 {
+		// Delegate unmarshaling of documents.
+		outt := out.Type()
+		outk := out.Kind()
+		switch outk {
+		case reflect.Interface, reflect.Ptr, reflect.Struct, reflect.Map:
+			d.readDocTo(out)
+			return true
+		}
+		if setterStyle(outt) != setterNone {
+			d.readDocTo(out)
+			return true
+		}
+		if outk == reflect.Slice {
+			switch outt.Elem() {
+			case typeDocElem:
+				out.Set(d.readDocElems(outt))
+			case typeRawDocElem:
+				out.Set(d.readRawDocElems(outt))
+			default:
+				d.readDocTo(blackHole)
+			}
+			return true
+		}
+		d.readDocTo(blackHole)
+		return true
+	}
+
+	var in interface{}
+
+	switch kind {
+	case 0x01: // Float64
+		in = d.readFloat64()
+	case 0x02: // UTF-8 string
+		in = d.readStr()
+	case 0x03: // Document
+		panic("Can't happen. Handled above.")
+	case 0x04: // Array
+		outt := out.Type()
+		if setterStyle(outt) != setterNone {
+			// Skip the value so its data is handed to the setter below.
+			d.dropElem(kind)
+			break
+		}
+		for outt.Kind() == reflect.Ptr {
+			outt = outt.Elem()
+		}
+		switch outt.Kind() {
+		case reflect.Array:
+			d.readArrayDocTo(out)
+			return true
+		case reflect.Slice:
+			in = d.readSliceDoc(outt)
+		default:
+			in = d.readSliceDoc(typeSlice)
+		}
+	case 0x05: // Binary
+		b := d.readBinary()
+		if b.Kind == 0x00 || b.Kind == 0x02 {
+			in = b.Data
+		} else {
+			in = b
+		}
+	case 0x06: // Undefined (obsolete, but still seen in the wild)
+		in = Undefined
+	case 0x07: // ObjectId
+		in = ObjectId(d.readBytes(12))
+	case 0x08: // Bool
+		in = d.readBool()
+	case 0x09: // Timestamp
+		// MongoDB handles timestamps as milliseconds.
+		i := d.readInt64()
+		if i == -62135596800000 {
+			in = time.Time{} // In UTC for convenience.
+		} else {
+			in = time.Unix(i/1e3, i%1e3*1e6)
+		}
+	case 0x0A: // Nil
+		in = nil
+	case 0x0B: // RegEx
+		in = d.readRegEx()
+	case 0x0C:
+		in = DBPointer{Namespace: d.readStr(), Id: ObjectId(d.readBytes(12))}
+	case 0x0D: // JavaScript without scope
+		in = JavaScript{Code: d.readStr()}
+	case 0x0E: // Symbol
+		in = Symbol(d.readStr())
+	case 0x0F: // JavaScript with scope
+		d.i += 4 // Skip length
+		js := JavaScript{d.readStr(), make(M)}
+		d.readDocTo(reflect.ValueOf(js.Scope))
+		in = js
+	case 0x10: // Int32
+		in = int(d.readInt32())
+	case 0x11: // Mongo-specific timestamp
+		in = MongoTimestamp(d.readInt64())
+	case 0x12: // Int64
+		in = d.readInt64()
+	case 0x13: // Decimal128
+		in = Decimal128{
+			l: uint64(d.readInt64()),
+			h: uint64(d.readInt64()),
+		}
+	case 0x7F: // Max key
+		in = MaxKey
+	case 0xFF: // Min key
+		in = MinKey
+	default:
+		panic(fmt.Sprintf("Unknown element kind (0x%02X)", kind))
+	}
+
+	outt := out.Type()
+
+	if outt == typeRaw {
+		out.Set(reflect.ValueOf(Raw{kind, d.in[start:d.i]}))
+		return true
+	}
+
+	if setter := getSetter(outt, out); setter != nil {
+		err := setter.SetBSON(Raw{kind, d.in[start:d.i]})
+		if err == SetZero {
+			out.Set(reflect.Zero(outt))
+			return true
+		}
+		if err == nil {
+			return true
+		}
+		if _, ok := err.(*TypeError); !ok {
+			panic(err)
+		}
+		return false
+	}
+
+	if in == nil {
+		out.Set(reflect.Zero(outt))
+		return true
+	}
+
+	outk := outt.Kind()
+
+	// Dereference and initialize pointer if necessary.
+	first := true
+	for outk == reflect.Ptr {
+		if !out.IsNil() {
+			out = out.Elem()
+		} else {
+			elem := reflect.New(outt.Elem())
+			if first {
+				// Only set if value is compatible.
+				first = false
+				defer func(out, elem reflect.Value) {
+					if good {
+						out.Set(elem)
+					}
+				}(out, elem)
+			} else {
+				out.Set(elem)
+			}
+			out = elem
+		}
+		outt = out.Type()
+		outk = outt.Kind()
+	}
+
+	inv := reflect.ValueOf(in)
+	if outt == inv.Type() {
+		out.Set(inv)
+		return true
+	}
+
+	switch outk {
+	case reflect.Interface:
+		out.Set(inv)
+		return true
+	case reflect.String:
+		switch inv.Kind() {
+		case reflect.String:
+			out.SetString(inv.String())
+			return true
+		case reflect.Slice:
+			if b, ok := in.([]byte); ok {
+				out.SetString(string(b))
+				return true
+			}
+		case reflect.Int, reflect.Int64:
+			if outt == typeJSONNumber {
+				out.SetString(strconv.FormatInt(inv.Int(), 10))
+				return true
+			}
+		case reflect.Float64:
+			if outt == typeJSONNumber {
+				out.SetString(strconv.FormatFloat(inv.Float(), 'f', -1, 64))
+				return true
+			}
+		}
+	case reflect.Slice, reflect.Array:
+		// Remember, array (0x04) slices are built with the correct
+		// element type.  If we are here, must be a cross BSON kind
+		// conversion (e.g. 0x05 unmarshalling on string).
+		if outt.Elem().Kind() != reflect.Uint8 {
+			break
+		}
+		switch inv.Kind() {
+		case reflect.String:
+			slice := []byte(inv.String())
+			out.Set(reflect.ValueOf(slice))
+			return true
+		case reflect.Slice:
+			switch outt.Kind() {
+			case reflect.Array:
+				reflect.Copy(out, inv)
+			case reflect.Slice:
+				out.SetBytes(inv.Bytes())
+			}
+			return true
+		}
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		switch inv.Kind() {
+		case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+			out.SetInt(inv.Int())
+			return true
+		case reflect.Float32, reflect.Float64:
+			out.SetInt(int64(inv.Float()))
+			return true
+		case reflect.Bool:
+			if inv.Bool() {
+				out.SetInt(1)
+			} else {
+				out.SetInt(0)
+			}
+			return true
+		case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+			panic("can't happen: no uint types in BSON (!?)")
+		}
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		switch inv.Kind() {
+		case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+			out.SetUint(uint64(inv.Int()))
+			return true
+		case reflect.Float32, reflect.Float64:
+			out.SetUint(uint64(inv.Float()))
+			return true
+		case reflect.Bool:
+			if inv.Bool() {
+				out.SetUint(1)
+			} else {
+				out.SetUint(0)
+			}
+			return true
+		case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+			panic("Can't happen. No uint types in BSON.")
+		}
+	case reflect.Float32, reflect.Float64:
+		switch inv.Kind() {
+		case reflect.Float32, reflect.Float64:
+			out.SetFloat(inv.Float())
+			return true
+		case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+			out.SetFloat(float64(inv.Int()))
+			return true
+		case reflect.Bool:
+			if inv.Bool() {
+				out.SetFloat(1)
+			} else {
+				out.SetFloat(0)
+			}
+			return true
+		case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+			panic("Can't happen. No uint types in BSON?")
+		}
+	case reflect.Bool:
+		switch inv.Kind() {
+		case reflect.Bool:
+			out.SetBool(inv.Bool())
+			return true
+		case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+			out.SetBool(inv.Int() != 0)
+			return true
+		case reflect.Float32, reflect.Float64:
+			out.SetBool(inv.Float() != 0)
+			return true
+		case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+			panic("Can't happen. No uint types in BSON?")
+		}
+	case reflect.Struct:
+		if outt == typeURL && inv.Kind() == reflect.String {
+			u, err := url.Parse(inv.String())
+			if err != nil {
+				panic(err)
+			}
+			out.Set(reflect.ValueOf(u).Elem())
+			return true
+		}
+		if outt == typeBinary {
+			if b, ok := in.([]byte); ok {
+				out.Set(reflect.ValueOf(Binary{Data: b}))
+				return true
+			}
+		}
+	}
+
+	return false
+}
+
+// --------------------------------------------------------------------------
+// Parsers of basic types.
+
+func (d *decoder) readRegEx() RegEx {
+	re := RegEx{}
+	re.Pattern = d.readCStr()
+	re.Options = d.readCStr()
+	return re
+}
+
+func (d *decoder) readBinary() Binary {
+	l := d.readInt32()
+	b := Binary{}
+	b.Kind = d.readByte()
+	b.Data = d.readBytes(l)
+	if b.Kind == 0x02 && len(b.Data) >= 4 {
+		// Weird obsolete format with redundant length.
+		b.Data = b.Data[4:]
+	}
+	return b
+}
+
+func (d *decoder) readStr() string {
+	l := d.readInt32()
+	b := d.readBytes(l - 1)
+	if d.readByte() != '\x00' {
+		corrupted()
+	}
+	return string(b)
+}
+
+func (d *decoder) readCStr() string {
+	start := d.i
+	end := start
+	l := len(d.in)
+	for ; end != l; end++ {
+		if d.in[end] == '\x00' {
+			break
+		}
+	}
+	d.i = end + 1
+	if d.i > l {
+		corrupted()
+	}
+	return string(d.in[start:end])
+}
+
+func (d *decoder) readBool() bool {
+	b := d.readByte()
+	if b == 0 {
+		return false
+	}
+	if b == 1 {
+		return true
+	}
+	panic(fmt.Sprintf("encoded boolean must be 1 or 0, found %d", b))
+}
+
+func (d *decoder) readFloat64() float64 {
+	return math.Float64frombits(uint64(d.readInt64()))
+}
+
+func (d *decoder) readInt32() int32 {
+	b := d.readBytes(4)
+	return int32((uint32(b[0]) << 0) |
+		(uint32(b[1]) << 8) |
+		(uint32(b[2]) << 16) |
+		(uint32(b[3]) << 24))
+}
+
+func (d *decoder) readInt64() int64 {
+	b := d.readBytes(8)
+	return int64((uint64(b[0]) << 0) |
+		(uint64(b[1]) << 8) |
+		(uint64(b[2]) << 16) |
+		(uint64(b[3]) << 24) |
+		(uint64(b[4]) << 32) |
+		(uint64(b[5]) << 40) |
+		(uint64(b[6]) << 48) |
+		(uint64(b[7]) << 56))
+}
+
+func (d *decoder) readByte() byte {
+	i := d.i
+	d.i++
+	if d.i > len(d.in) {
+		corrupted()
+	}
+	return d.in[i]
+}
+
+func (d *decoder) readBytes(length int32) []byte {
+	if length < 0 {
+		corrupted()
+	}
+	start := d.i
+	d.i += int(length)
+	if d.i < start || d.i > len(d.in) {
+		corrupted()
+	}
+	return d.in[start : start+int(length)]
+}

vendor/gopkg.in/mgo.v2/bson/encode.go

@@ -0,0 +1,514 @@
+// BSON library for Go
+//
+// Copyright (c) 2010-2012 - Gustavo Niemeyer <gustavo@niemeyer.net>
+//
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this
+//    list of conditions and the following disclaimer.
+// 2. Redistributions in binary form must reproduce the above copyright notice,
+//    this list of conditions and the following disclaimer in the documentation
+//    and/or other materials provided with the distribution.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+// ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+// gobson - BSON library for Go.
+
+package bson
+
+import (
+	"encoding/json"
+	"fmt"
+	"math"
+	"net/url"
+	"reflect"
+	"strconv"
+	"time"
+)
+
+// --------------------------------------------------------------------------
+// Some internal infrastructure.
+
+var (
+	typeBinary         = reflect.TypeOf(Binary{})
+	typeObjectId       = reflect.TypeOf(ObjectId(""))
+	typeDBPointer      = reflect.TypeOf(DBPointer{"", ObjectId("")})
+	typeSymbol         = reflect.TypeOf(Symbol(""))
+	typeMongoTimestamp = reflect.TypeOf(MongoTimestamp(0))
+	typeOrderKey       = reflect.TypeOf(MinKey)
+	typeDocElem        = reflect.TypeOf(DocElem{})
+	typeRawDocElem     = reflect.TypeOf(RawDocElem{})
+	typeRaw            = reflect.TypeOf(Raw{})
+	typeURL            = reflect.TypeOf(url.URL{})
+	typeTime           = reflect.TypeOf(time.Time{})
+	typeString         = reflect.TypeOf("")
+	typeJSONNumber     = reflect.TypeOf(json.Number(""))
+)
+
+const itoaCacheSize = 32
+
+var itoaCache []string
+
+func init() {
+	itoaCache = make([]string, itoaCacheSize)
+	for i := 0; i != itoaCacheSize; i++ {
+		itoaCache[i] = strconv.Itoa(i)
+	}
+}
+
+func itoa(i int) string {
+	if i < itoaCacheSize {
+		return itoaCache[i]
+	}
+	return strconv.Itoa(i)
+}
+
+// --------------------------------------------------------------------------
+// Marshaling of the document value itself.
+
+type encoder struct {
+	out []byte
+}
+
+func (e *encoder) addDoc(v reflect.Value) {
+	for {
+		if vi, ok := v.Interface().(Getter); ok {
+			getv, err := vi.GetBSON()
+			if err != nil {
+				panic(err)
+			}
+			v = reflect.ValueOf(getv)
+			continue
+		}
+		if v.Kind() == reflect.Ptr {
+			v = v.Elem()
+			continue
+		}
+		break
+	}
+
+	if v.Type() == typeRaw {
+		raw := v.Interface().(Raw)
+		if raw.Kind != 0x03 && raw.Kind != 0x00 {
+			panic("Attempted to marshal Raw kind " + strconv.Itoa(int(raw.Kind)) + " as a document")
+		}
+		if len(raw.Data) == 0 {
+			panic("Attempted to marshal empty Raw document")
+		}
+		e.addBytes(raw.Data...)
+		return
+	}
+
+	start := e.reserveInt32()
+
+	switch v.Kind() {
+	case reflect.Map:
+		e.addMap(v)
+	case reflect.Struct:
+		e.addStruct(v)
+	case reflect.Array, reflect.Slice:
+		e.addSlice(v)
+	default:
+		panic("Can't marshal " + v.Type().String() + " as a BSON document")
+	}
+
+	e.addBytes(0)
+	e.setInt32(start, int32(len(e.out)-start))
+}
+
+func (e *encoder) addMap(v reflect.Value) {
+	for _, k := range v.MapKeys() {
+		e.addElem(k.String(), v.MapIndex(k), false)
+	}
+}
+
+func (e *encoder) addStruct(v reflect.Value) {
+	sinfo, err := getStructInfo(v.Type())
+	if err != nil {
+		panic(err)
+	}
+	var value reflect.Value
+	if sinfo.InlineMap >= 0 {
+		m := v.Field(sinfo.InlineMap)
+		if m.Len() > 0 {
+			for _, k := range m.MapKeys() {
+				ks := k.String()
+				if _, found := sinfo.FieldsMap[ks]; found {
+					panic(fmt.Sprintf("Can't have key %q in inlined map; conflicts with struct field", ks))
+				}
+				e.addElem(ks, m.MapIndex(k), false)
+			}
+		}
+	}
+	for _, info := range sinfo.FieldsList {
+		if info.Inline == nil {
+			value = v.Field(info.Num)
+		} else {
+			value = v.FieldByIndex(info.Inline)
+		}
+		if info.OmitEmpty && isZero(value) {
+			continue
+		}
+		e.addElem(info.Key, value, info.MinSize)
+	}
+}
+
+func isZero(v reflect.Value) bool {
+	switch v.Kind() {
+	case reflect.String:
+		return len(v.String()) == 0
+	case reflect.Ptr, reflect.Interface:
+		return v.IsNil()
+	case reflect.Slice:
+		return v.Len() == 0
+	case reflect.Map:
+		return v.Len() == 0
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return v.Int() == 0
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		return v.Uint() == 0
+	case reflect.Float32, reflect.Float64:
+		return v.Float() == 0
+	case reflect.Bool:
+		return !v.Bool()
+	case reflect.Struct:
+		vt := v.Type()
+		if vt == typeTime {
+			return v.Interface().(time.Time).IsZero()
+		}
+		for i := 0; i < v.NumField(); i++ {
+			if vt.Field(i).PkgPath != "" && !vt.Field(i).Anonymous {
+				continue // Private field
+			}
+			if !isZero(v.Field(i)) {
+				return false
+			}
+		}
+		return true
+	}
+	return false
+}
+
+func (e *encoder) addSlice(v reflect.Value) {
+	vi := v.Interface()
+	if d, ok := vi.(D); ok {
+		for _, elem := range d {
+			e.addElem(elem.Name, reflect.ValueOf(elem.Value), false)
+		}
+		return
+	}
+	if d, ok := vi.(RawD); ok {
+		for _, elem := range d {
+			e.addElem(elem.Name, reflect.ValueOf(elem.Value), false)
+		}
+		return
+	}
+	l := v.Len()
+	et := v.Type().Elem()
+	if et == typeDocElem {
+		for i := 0; i < l; i++ {
+			elem := v.Index(i).Interface().(DocElem)
+			e.addElem(elem.Name, reflect.ValueOf(elem.Value), false)
+		}
+		return
+	}
+	if et == typeRawDocElem {
+		for i := 0; i < l; i++ {
+			elem := v.Index(i).Interface().(RawDocElem)
+			e.addElem(elem.Name, reflect.ValueOf(elem.Value), false)
+		}
+		return
+	}
+	for i := 0; i < l; i++ {
+		e.addElem(itoa(i), v.Index(i), false)
+	}
+}
+
+// --------------------------------------------------------------------------
+// Marshaling of elements in a document.
+
+func (e *encoder) addElemName(kind byte, name string) {
+	e.addBytes(kind)
+	e.addBytes([]byte(name)...)
+	e.addBytes(0)
+}
+
+func (e *encoder) addElem(name string, v reflect.Value, minSize bool) {
+
+	if !v.IsValid() {
+		e.addElemName(0x0A, name)
+		return
+	}
+
+	if getter, ok := v.Interface().(Getter); ok {
+		getv, err := getter.GetBSON()
+		if err != nil {
+			panic(err)
+		}
+		e.addElem(name, reflect.ValueOf(getv), minSize)
+		return
+	}
+
+	switch v.Kind() {
+
+	case reflect.Interface:
+		e.addElem(name, v.Elem(), minSize)
+
+	case reflect.Ptr:
+		e.addElem(name, v.Elem(), minSize)
+
+	case reflect.String:
+		s := v.String()
+		switch v.Type() {
+		case typeObjectId:
+			if len(s) != 12 {
+				panic("ObjectIDs must be exactly 12 bytes long (got " +
+					strconv.Itoa(len(s)) + ")")
+			}
+			e.addElemName(0x07, name)
+			e.addBytes([]byte(s)...)
+		case typeSymbol:
+			e.addElemName(0x0E, name)
+			e.addStr(s)
+		case typeJSONNumber:
+			n := v.Interface().(json.Number)
+			if i, err := n.Int64(); err == nil {
+				e.addElemName(0x12, name)
+				e.addInt64(i)
+			} else if f, err := n.Float64(); err == nil {
+				e.addElemName(0x01, name)
+				e.addFloat64(f)
+			} else {
+				panic("failed to convert json.Number to a number: " + s)
+			}
+		default:
+			e.addElemName(0x02, name)
+			e.addStr(s)
+		}
+
+	case reflect.Float32, reflect.Float64:
+		e.addElemName(0x01, name)
+		e.addFloat64(v.Float())
+
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		u := v.Uint()
+		if int64(u) < 0 {
+			panic("BSON has no uint64 type, and value is too large to fit correctly in an int64")
+		} else if u <= math.MaxInt32 && (minSize || v.Kind() <= reflect.Uint32) {
+			e.addElemName(0x10, name)
+			e.addInt32(int32(u))
+		} else {
+			e.addElemName(0x12, name)
+			e.addInt64(int64(u))
+		}
+
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		switch v.Type() {
+		case typeMongoTimestamp:
+			e.addElemName(0x11, name)
+			e.addInt64(v.Int())
+
+		case typeOrderKey:
+			if v.Int() == int64(MaxKey) {
+				e.addElemName(0x7F, name)
+			} else {
+				e.addElemName(0xFF, name)
+			}
+
+		default:
+			i := v.Int()
+			if (minSize || v.Type().Kind() != reflect.Int64) && i >= math.MinInt32 && i <= math.MaxInt32 {
+				// It fits into an int32, encode as such.
+				e.addElemName(0x10, name)
+				e.addInt32(int32(i))
+			} else {
+				e.addElemName(0x12, name)
+				e.addInt64(i)
+			}
+		}
+
+	case reflect.Bool:
+		e.addElemName(0x08, name)
+		if v.Bool() {
+			e.addBytes(1)
+		} else {
+			e.addBytes(0)
+		}
+
+	case reflect.Map:
+		e.addElemName(0x03, name)
+		e.addDoc(v)
+
+	case reflect.Slice:
+		vt := v.Type()
+		et := vt.Elem()
+		if et.Kind() == reflect.Uint8 {
+			e.addElemName(0x05, name)
+			e.addBinary(0x00, v.Bytes())
+		} else if et == typeDocElem || et == typeRawDocElem {
+			e.addElemName(0x03, name)
+			e.addDoc(v)
+		} else {
+			e.addElemName(0x04, name)
+			e.addDoc(v)
+		}
+
+	case reflect.Array:
+		et := v.Type().Elem()
+		if et.Kind() == reflect.Uint8 {
+			e.addElemName(0x05, name)
+			if v.CanAddr() {
+				e.addBinary(0x00, v.Slice(0, v.Len()).Interface().([]byte))
+			} else {
+				n := v.Len()
+				e.addInt32(int32(n))
+				e.addBytes(0x00)
+				for i := 0; i < n; i++ {
+					el := v.Index(i)
+					e.addBytes(byte(el.Uint()))
+				}
+			}
+		} else {
+			e.addElemName(0x04, name)
+			e.addDoc(v)
+		}
+
+	case reflect.Struct:
+		switch s := v.Interface().(type) {
+
+		case Raw:
+			kind := s.Kind
+			if kind == 0x00 {
+				kind = 0x03
+			}
+			if len(s.Data) == 0 && kind != 0x06 && kind != 0x0A && kind != 0xFF && kind != 0x7F {
+				panic("Attempted to marshal empty Raw document")
+			}
+			e.addElemName(kind, name)
+			e.addBytes(s.Data...)
+
+		case Binary:
+			e.addElemName(0x05, name)
+			e.addBinary(s.Kind, s.Data)
+
+		case Decimal128:
+			e.addElemName(0x13, name)
+			e.addInt64(int64(s.l))
+			e.addInt64(int64(s.h))
+
+		case DBPointer:
+			e.addElemName(0x0C, name)
+			e.addStr(s.Namespace)
+			if len(s.Id) != 12 {
+				panic("ObjectIDs must be exactly 12 bytes long (got " +
+					strconv.Itoa(len(s.Id)) + ")")
+			}
+			e.addBytes([]byte(s.Id)...)
+
+		case RegEx:
+			e.addElemName(0x0B, name)
+			e.addCStr(s.Pattern)
+			e.addCStr(s.Options)
+
+		case JavaScript:
+			if s.Scope == nil {
+				e.addElemName(0x0D, name)
+				e.addStr(s.Code)
+			} else {
+				e.addElemName(0x0F, name)
+				start := e.reserveInt32()
+				e.addStr(s.Code)
+				e.addDoc(reflect.ValueOf(s.Scope))
+				e.setInt32(start, int32(len(e.out)-start))
+			}
+
+		case time.Time:
+			// MongoDB handles timestamps as milliseconds.
+			e.addElemName(0x09, name)
+			e.addInt64(s.Unix()*1000 + int64(s.Nanosecond()/1e6))
+
+		case url.URL:
+			e.addElemName(0x02, name)
+			e.addStr(s.String())
+
+		case undefined:
+			e.addElemName(0x06, name)
+
+		default:
+			e.addElemName(0x03, name)
+			e.addDoc(v)
+		}
+
+	default:
+		panic("Can't marshal " + v.Type().String() + " in a BSON document")
+	}
+}
+
+// --------------------------------------------------------------------------
+// Marshaling of base types.
+
+func (e *encoder) addBinary(subtype byte, v []byte) {
+	if subtype == 0x02 {
+		// Wonder how that brilliant idea came to life. Obsolete, luckily.
+		e.addInt32(int32(len(v) + 4))
+		e.addBytes(subtype)
+		e.addInt32(int32(len(v)))
+	} else {
+		e.addInt32(int32(len(v)))
+		e.addBytes(subtype)
+	}
+	e.addBytes(v...)
+}
+
+func (e *encoder) addStr(v string) {
+	e.addInt32(int32(len(v) + 1))
+	e.addCStr(v)
+}
+
+func (e *encoder) addCStr(v string) {
+	e.addBytes([]byte(v)...)
+	e.addBytes(0)
+}
+
+func (e *encoder) reserveInt32() (pos int) {
+	pos = len(e.out)
+	e.addBytes(0, 0, 0, 0)
+	return pos
+}
+
+func (e *encoder) setInt32(pos int, v int32) {
+	e.out[pos+0] = byte(v)
+	e.out[pos+1] = byte(v >> 8)
+	e.out[pos+2] = byte(v >> 16)
+	e.out[pos+3] = byte(v >> 24)
+}
+
+func (e *encoder) addInt32(v int32) {
+	u := uint32(v)
+	e.addBytes(byte(u), byte(u>>8), byte(u>>16), byte(u>>24))
+}
+
+func (e *encoder) addInt64(v int64) {
+	u := uint64(v)
+	e.addBytes(byte(u), byte(u>>8), byte(u>>16), byte(u>>24),
+		byte(u>>32), byte(u>>40), byte(u>>48), byte(u>>56))
+}
+
+func (e *encoder) addFloat64(v float64) {
+	e.addInt64(int64(math.Float64bits(v)))
+}
+
+func (e *encoder) addBytes(v ...byte) {
+	e.out = append(e.out, v...)
+}

vendor/gopkg.in/mgo.v2/bson/json.go

@@ -0,0 +1,380 @@
+package bson
+
+import (
+	"bytes"
+	"encoding/base64"
+	"fmt"
+	"gopkg.in/mgo.v2/internal/json"
+	"strconv"
+	"time"
+)
+
+// UnmarshalJSON unmarshals a JSON value that may hold non-standard
+// syntax as defined in BSON's extended JSON specification.
+func UnmarshalJSON(data []byte, value interface{}) error {
+	d := json.NewDecoder(bytes.NewBuffer(data))
+	d.Extend(&jsonExt)
+	return d.Decode(value)
+}
+
+// MarshalJSON marshals a JSON value that may hold non-standard
+// syntax as defined in BSON's extended JSON specification.
+func MarshalJSON(value interface{}) ([]byte, error) {
+	var buf bytes.Buffer
+	e := json.NewEncoder(&buf)
+	e.Extend(&jsonExt)
+	err := e.Encode(value)
+	if err != nil {
+		return nil, err
+	}
+	return buf.Bytes(), nil
+}
+
+// jdec is used internally by the JSON decoding functions
+// so they may unmarshal functions without getting into endless
+// recursion due to keyed objects.
+func jdec(data []byte, value interface{}) error {
+	d := json.NewDecoder(bytes.NewBuffer(data))
+	d.Extend(&funcExt)
+	return d.Decode(value)
+}
+
+var jsonExt json.Extension
+var funcExt json.Extension
+
+// TODO
+// - Shell regular expressions ("/regexp/opts")
+
+func init() {
+	jsonExt.DecodeUnquotedKeys(true)
+	jsonExt.DecodeTrailingCommas(true)
+
+	funcExt.DecodeFunc("BinData", "$binaryFunc", "$type", "$binary")
+	jsonExt.DecodeKeyed("$binary", jdecBinary)
+	jsonExt.DecodeKeyed("$binaryFunc", jdecBinary)
+	jsonExt.EncodeType([]byte(nil), jencBinarySlice)
+	jsonExt.EncodeType(Binary{}, jencBinaryType)
+
+	funcExt.DecodeFunc("ISODate", "$dateFunc", "S")
+	funcExt.DecodeFunc("new Date", "$dateFunc", "S")
+	jsonExt.DecodeKeyed("$date", jdecDate)
+	jsonExt.DecodeKeyed("$dateFunc", jdecDate)
+	jsonExt.EncodeType(time.Time{}, jencDate)
+
+	funcExt.DecodeFunc("Timestamp", "$timestamp", "t", "i")
+	jsonExt.DecodeKeyed("$timestamp", jdecTimestamp)
+	jsonExt.EncodeType(MongoTimestamp(0), jencTimestamp)
+
+	funcExt.DecodeConst("undefined", Undefined)
+
+	jsonExt.DecodeKeyed("$regex", jdecRegEx)
+	jsonExt.EncodeType(RegEx{}, jencRegEx)
+
+	funcExt.DecodeFunc("ObjectId", "$oidFunc", "Id")
+	jsonExt.DecodeKeyed("$oid", jdecObjectId)
+	jsonExt.DecodeKeyed("$oidFunc", jdecObjectId)
+	jsonExt.EncodeType(ObjectId(""), jencObjectId)
+
+	funcExt.DecodeFunc("DBRef", "$dbrefFunc", "$ref", "$id")
+	jsonExt.DecodeKeyed("$dbrefFunc", jdecDBRef)
+
+	funcExt.DecodeFunc("NumberLong", "$numberLongFunc", "N")
+	jsonExt.DecodeKeyed("$numberLong", jdecNumberLong)
+	jsonExt.DecodeKeyed("$numberLongFunc", jdecNumberLong)
+	jsonExt.EncodeType(int64(0), jencNumberLong)
+	jsonExt.EncodeType(int(0), jencInt)
+
+	funcExt.DecodeConst("MinKey", MinKey)
+	funcExt.DecodeConst("MaxKey", MaxKey)
+	jsonExt.DecodeKeyed("$minKey", jdecMinKey)
+	jsonExt.DecodeKeyed("$maxKey", jdecMaxKey)
+	jsonExt.EncodeType(orderKey(0), jencMinMaxKey)
+
+	jsonExt.DecodeKeyed("$undefined", jdecUndefined)
+	jsonExt.EncodeType(Undefined, jencUndefined)
+
+	jsonExt.Extend(&funcExt)
+}
+
+func fbytes(format string, args ...interface{}) []byte {
+	var buf bytes.Buffer
+	fmt.Fprintf(&buf, format, args...)
+	return buf.Bytes()
+}
+
+func jdecBinary(data []byte) (interface{}, error) {
+	var v struct {
+		Binary []byte `json:"$binary"`
+		Type   string `json:"$type"`
+		Func   struct {
+			Binary []byte `json:"$binary"`
+			Type   int64  `json:"$type"`
+		} `json:"$binaryFunc"`
+	}
+	err := jdec(data, &v)
+	if err != nil {
+		return nil, err
+	}
+
+	var binData []byte
+	var binKind int64
+	if v.Type == "" && v.Binary == nil {
+		binData = v.Func.Binary
+		binKind = v.Func.Type
+	} else if v.Type == "" {
+		return v.Binary, nil
+	} else {
+		binData = v.Binary
+		binKind, err = strconv.ParseInt(v.Type, 0, 64)
+		if err != nil {
+			binKind = -1
+		}
+	}
+
+	if binKind == 0 {
+		return binData, nil
+	}
+	if binKind < 0 || binKind > 255 {
+		return nil, fmt.Errorf("invalid type in binary object: %s", data)
+	}
+
+	return Binary{Kind: byte(binKind), Data: binData}, nil
+}
+
+func jencBinarySlice(v interface{}) ([]byte, error) {
+	in := v.([]byte)
+	out := make([]byte, base64.StdEncoding.EncodedLen(len(in)))
+	base64.StdEncoding.Encode(out, in)
+	return fbytes(`{"$binary":"%s","$type":"0x0"}`, out), nil
+}
+
+func jencBinaryType(v interface{}) ([]byte, error) {
+	in := v.(Binary)
+	out := make([]byte, base64.StdEncoding.EncodedLen(len(in.Data)))
+	base64.StdEncoding.Encode(out, in.Data)
+	return fbytes(`{"$binary":"%s","$type":"0x%x"}`, out, in.Kind), nil
+}
+
+const jdateFormat = "2006-01-02T15:04:05.999Z"
+
+func jdecDate(data []byte) (interface{}, error) {
+	var v struct {
+		S    string `json:"$date"`
+		Func struct {
+			S string
+		} `json:"$dateFunc"`
+	}
+	_ = jdec(data, &v)
+	if v.S == "" {
+		v.S = v.Func.S
+	}
+	if v.S != "" {
+		for _, format := range []string{jdateFormat, "2006-01-02"} {
+			t, err := time.Parse(format, v.S)
+			if err == nil {
+				return t, nil
+			}
+		}
+		return nil, fmt.Errorf("cannot parse date: %q", v.S)
+	}
+
+	var vn struct {
+		Date struct {
+			N int64 `json:"$numberLong,string"`
+		} `json:"$date"`
+		Func struct {
+			S int64
+		} `json:"$dateFunc"`
+	}
+	err := jdec(data, &vn)
+	if err != nil {
+		return nil, fmt.Errorf("cannot parse date: %q", data)
+	}
+	n := vn.Date.N
+	if n == 0 {
+		n = vn.Func.S
+	}
+	return time.Unix(n/1000, n%1000*1e6).UTC(), nil
+}
+
+func jencDate(v interface{}) ([]byte, error) {
+	t := v.(time.Time)
+	return fbytes(`{"$date":%q}`, t.Format(jdateFormat)), nil
+}
+
+func jdecTimestamp(data []byte) (interface{}, error) {
+	var v struct {
+		Func struct {
+			T int32 `json:"t"`
+			I int32 `json:"i"`
+		} `json:"$timestamp"`
+	}
+	err := jdec(data, &v)
+	if err != nil {
+		return nil, err
+	}
+	return MongoTimestamp(uint64(v.Func.T)<<32 | uint64(uint32(v.Func.I))), nil
+}
+
+func jencTimestamp(v interface{}) ([]byte, error) {
+	ts := uint64(v.(MongoTimestamp))
+	return fbytes(`{"$timestamp":{"t":%d,"i":%d}}`, ts>>32, uint32(ts)), nil
+}
+
+func jdecRegEx(data []byte) (interface{}, error) {
+	var v struct {
+		Regex   string `json:"$regex"`
+		Options string `json:"$options"`
+	}
+	err := jdec(data, &v)
+	if err != nil {
+		return nil, err
+	}
+	return RegEx{v.Regex, v.Options}, nil
+}
+
+func jencRegEx(v interface{}) ([]byte, error) {
+	re := v.(RegEx)
+	type regex struct {
+		Regex   string `json:"$regex"`
+		Options string `json:"$options"`
+	}
+	return json.Marshal(regex{re.Pattern, re.Options})
+}
+
+func jdecObjectId(data []byte) (interface{}, error) {
+	var v struct {
+		Id   string `json:"$oid"`
+		Func struct {
+			Id string
+		} `json:"$oidFunc"`
+	}
+	err := jdec(data, &v)
+	if err != nil {
+		return nil, err
+	}
+	if v.Id == "" {
+		v.Id = v.Func.Id
+	}
+	return ObjectIdHex(v.Id), nil
+}
+
+func jencObjectId(v interface{}) ([]byte, error) {
+	return fbytes(`{"$oid":"%s"}`, v.(ObjectId).Hex()), nil
+}
+
+func jdecDBRef(data []byte) (interface{}, error) {
+	// TODO Support unmarshaling $ref and $id into the input value.
+	var v struct {
+		Obj map[string]interface{} `json:"$dbrefFunc"`
+	}
+	// TODO Fix this. Must not be required.
+	v.Obj = make(map[string]interface{})
+	err := jdec(data, &v)
+	if err != nil {
+		return nil, err
+	}
+	return v.Obj, nil
+}
+
+func jdecNumberLong(data []byte) (interface{}, error) {
+	var v struct {
+		N    int64 `json:"$numberLong,string"`
+		Func struct {
+			N int64 `json:",string"`
+		} `json:"$numberLongFunc"`
+	}
+	var vn struct {
+		N    int64 `json:"$numberLong"`
+		Func struct {
+			N int64
+		} `json:"$numberLongFunc"`
+	}
+	err := jdec(data, &v)
+	if err != nil {
+		err = jdec(data, &vn)
+		v.N = vn.N
+		v.Func.N = vn.Func.N
+	}
+	if err != nil {
+		return nil, err
+	}
+	if v.N != 0 {
+		return v.N, nil
+	}
+	return v.Func.N, nil
+}
+
+func jencNumberLong(v interface{}) ([]byte, error) {
+	n := v.(int64)
+	f := `{"$numberLong":"%d"}`
+	if n <= 1<<53 {
+		f = `{"$numberLong":%d}`
+	}
+	return fbytes(f, n), nil
+}
+
+func jencInt(v interface{}) ([]byte, error) {
+	n := v.(int)
+	f := `{"$numberLong":"%d"}`
+	if int64(n) <= 1<<53 {
+		f = `%d`
+	}
+	return fbytes(f, n), nil
+}
+
+func jdecMinKey(data []byte) (interface{}, error) {
+	var v struct {
+		N int64 `json:"$minKey"`
+	}
+	err := jdec(data, &v)
+	if err != nil {
+		return nil, err
+	}
+	if v.N != 1 {
+		return nil, fmt.Errorf("invalid $minKey object: %s", data)
+	}
+	return MinKey, nil
+}
+
+func jdecMaxKey(data []byte) (interface{}, error) {
+	var v struct {
+		N int64 `json:"$maxKey"`
+	}
+	err := jdec(data, &v)
+	if err != nil {
+		return nil, err
+	}
+	if v.N != 1 {
+		return nil, fmt.Errorf("invalid $maxKey object: %s", data)
+	}
+	return MaxKey, nil
+}
+
+func jencMinMaxKey(v interface{}) ([]byte, error) {
+	switch v.(orderKey) {
+	case MinKey:
+		return []byte(`{"$minKey":1}`), nil
+	case MaxKey:
+		return []byte(`{"$maxKey":1}`), nil
+	}
+	panic(fmt.Sprintf("invalid $minKey/$maxKey value: %d", v))
+}
+
+func jdecUndefined(data []byte) (interface{}, error) {
+	var v struct {
+		B bool `json:"$undefined"`
+	}
+	err := jdec(data, &v)
+	if err != nil {
+		return nil, err
+	}
+	if !v.B {
+		return nil, fmt.Errorf("invalid $undefined object: %s", data)
+	}
+	return Undefined, nil
+}
+
+func jencUndefined(v interface{}) ([]byte, error) {
+	return []byte(`{"$undefined":true}`), nil
+}

vendor/gopkg.in/mgo.v2/bulk.go

@@ -0,0 +1,351 @@
+package mgo
+
+import (
+	"bytes"
+	"sort"
+
+	"gopkg.in/mgo.v2/bson"
+)
+
+// Bulk represents an operation that can be prepared with several
+// orthogonal changes before being delivered to the server.
+//
+// MongoDB servers older than version 2.6 do not have proper support for bulk
+// operations, so the driver attempts to map its API as much as possible into
+// the functionality that works. In particular, in those releases updates and
+// removals are sent individually, and inserts are sent in bulk but have
+// suboptimal error reporting compared to more recent versions of the server.
+// See the documentation of BulkErrorCase for details on that.
+//
+// Relevant documentation:
+//
+//   http://blog.mongodb.org/post/84922794768/mongodbs-new-bulk-api
+//
+type Bulk struct {
+	c       *Collection
+	opcount int
+	actions []bulkAction
+	ordered bool
+}
+
+type bulkOp int
+
+const (
+	bulkInsert bulkOp = iota + 1
+	bulkUpdate
+	bulkUpdateAll
+	bulkRemove
+)
+
+type bulkAction struct {
+	op   bulkOp
+	docs []interface{}
+	idxs []int
+}
+
+type bulkUpdateOp []interface{}
+type bulkDeleteOp []interface{}
+
+// BulkResult holds the results for a bulk operation.
+type BulkResult struct {
+	Matched  int
+	Modified int // Available only for MongoDB 2.6+
+
+	// Be conservative while we understand exactly how to report these
+	// results in a useful and convenient way, and also how to emulate
+	// them with prior servers.
+	private bool
+}
+
+// BulkError holds an error returned from running a Bulk operation.
+// Individual errors may be obtained and inspected via the Cases method.
+type BulkError struct {
+	ecases []BulkErrorCase
+}
+
+func (e *BulkError) Error() string {
+	if len(e.ecases) == 0 {
+		return "invalid BulkError instance: no errors"
+	}
+	if len(e.ecases) == 1 {
+		return e.ecases[0].Err.Error()
+	}
+	msgs := make([]string, 0, len(e.ecases))
+	seen := make(map[string]bool)
+	for _, ecase := range e.ecases {
+		msg := ecase.Err.Error()
+		if !seen[msg] {
+			seen[msg] = true
+			msgs = append(msgs, msg)
+		}
+	}
+	if len(msgs) == 1 {
+		return msgs[0]
+	}
+	var buf bytes.Buffer
+	buf.WriteString("multiple errors in bulk operation:\n")
+	for _, msg := range msgs {
+		buf.WriteString("  - ")
+		buf.WriteString(msg)
+		buf.WriteByte('\n')
+	}
+	return buf.String()
+}
+
+type bulkErrorCases []BulkErrorCase
+
+func (slice bulkErrorCases) Len() int           { return len(slice) }
+func (slice bulkErrorCases) Less(i, j int) bool { return slice[i].Index < slice[j].Index }
+func (slice bulkErrorCases) Swap(i, j int)      { slice[i], slice[j] = slice[j], slice[i] }
+
+// BulkErrorCase holds an individual error found while attempting a single change
+// within a bulk operation, and the position in which it was enqueued.
+//
+// MongoDB servers older than version 2.6 do not have proper support for bulk
+// operations, so the driver attempts to map its API as much as possible into
+// the functionality that works. In particular, only the last error is reported
+// for bulk inserts and without any positional information, so the Index
+// field is set to -1 in these cases.
+type BulkErrorCase struct {
+	Index int // Position of operation that failed, or -1 if unknown.
+	Err   error
+}
+
+// Cases returns all individual errors found while attempting the requested changes.
+//
+// See the documentation of BulkErrorCase for limitations in older MongoDB releases.
+func (e *BulkError) Cases() []BulkErrorCase {
+	return e.ecases
+}
+
+// Bulk returns a value to prepare the execution of a bulk operation.
+func (c *Collection) Bulk() *Bulk {
+	return &Bulk{c: c, ordered: true}
+}
+
+// Unordered puts the bulk operation in unordered mode.
+//
+// In unordered mode the indvidual operations may be sent
+// out of order, which means latter operations may proceed
+// even if prior ones have failed.
+func (b *Bulk) Unordered() {
+	b.ordered = false
+}
+
+func (b *Bulk) action(op bulkOp, opcount int) *bulkAction {
+	var action *bulkAction
+	if len(b.actions) > 0 && b.actions[len(b.actions)-1].op == op {
+		action = &b.actions[len(b.actions)-1]
+	} else if !b.ordered {
+		for i := range b.actions {
+			if b.actions[i].op == op {
+				action = &b.actions[i]
+				break
+			}
+		}
+	}
+	if action == nil {
+		b.actions = append(b.actions, bulkAction{op: op})
+		action = &b.actions[len(b.actions)-1]
+	}
+	for i := 0; i < opcount; i++ {
+		action.idxs = append(action.idxs, b.opcount)
+		b.opcount++
+	}
+	return action
+}
+
+// Insert queues up the provided documents for insertion.
+func (b *Bulk) Insert(docs ...interface{}) {
+	action := b.action(bulkInsert, len(docs))
+	action.docs = append(action.docs, docs...)
+}
+
+// Remove queues up the provided selectors for removing matching documents.
+// Each selector will remove only a single matching document.
+func (b *Bulk) Remove(selectors ...interface{}) {
+	action := b.action(bulkRemove, len(selectors))
+	for _, selector := range selectors {
+		if selector == nil {
+			selector = bson.D{}
+		}
+		action.docs = append(action.docs, &deleteOp{
+			Collection: b.c.FullName,
+			Selector:   selector,
+			Flags:      1,
+			Limit:      1,
+		})
+	}
+}
+
+// RemoveAll queues up the provided selectors for removing all matching documents.
+// Each selector will remove all matching documents.
+func (b *Bulk) RemoveAll(selectors ...interface{}) {
+	action := b.action(bulkRemove, len(selectors))
+	for _, selector := range selectors {
+		if selector == nil {
+			selector = bson.D{}
+		}
+		action.docs = append(action.docs, &deleteOp{
+			Collection: b.c.FullName,
+			Selector:   selector,
+			Flags:      0,
+			Limit:      0,
+		})
+	}
+}
+
+// Update queues up the provided pairs of updating instructions.
+// The first element of each pair selects which documents must be
+// updated, and the second element defines how to update it.
+// Each pair matches exactly one document for updating at most.
+func (b *Bulk) Update(pairs ...interface{}) {
+	if len(pairs)%2 != 0 {
+		panic("Bulk.Update requires an even number of parameters")
+	}
+	action := b.action(bulkUpdate, len(pairs)/2)
+	for i := 0; i < len(pairs); i += 2 {
+		selector := pairs[i]
+		if selector == nil {
+			selector = bson.D{}
+		}
+		action.docs = append(action.docs, &updateOp{
+			Collection: b.c.FullName,
+			Selector:   selector,
+			Update:     pairs[i+1],
+		})
+	}
+}
+
+// UpdateAll queues up the provided pairs of updating instructions.
+// The first element of each pair selects which documents must be
+// updated, and the second element defines how to update it.
+// Each pair updates all documents matching the selector.
+func (b *Bulk) UpdateAll(pairs ...interface{}) {
+	if len(pairs)%2 != 0 {
+		panic("Bulk.UpdateAll requires an even number of parameters")
+	}
+	action := b.action(bulkUpdate, len(pairs)/2)
+	for i := 0; i < len(pairs); i += 2 {
+		selector := pairs[i]
+		if selector == nil {
+			selector = bson.D{}
+		}
+		action.docs = append(action.docs, &updateOp{
+			Collection: b.c.FullName,
+			Selector:   selector,
+			Update:     pairs[i+1],
+			Flags:      2,
+			Multi:      true,
+		})
+	}
+}
+
+// Upsert queues up the provided pairs of upserting instructions.
+// The first element of each pair selects which documents must be
+// updated, and the second element defines how to update it.
+// Each pair matches exactly one document for updating at most.
+func (b *Bulk) Upsert(pairs ...interface{}) {
+	if len(pairs)%2 != 0 {
+		panic("Bulk.Update requires an even number of parameters")
+	}
+	action := b.action(bulkUpdate, len(pairs)/2)
+	for i := 0; i < len(pairs); i += 2 {
+		selector := pairs[i]
+		if selector == nil {
+			selector = bson.D{}
+		}
+		action.docs = append(action.docs, &updateOp{
+			Collection: b.c.FullName,
+			Selector:   selector,
+			Update:     pairs[i+1],
+			Flags:      1,
+			Upsert:     true,
+		})
+	}
+}
+
+// Run runs all the operations queued up.
+//
+// If an error is reported on an unordered bulk operation, the error value may
+// be an aggregation of all issues observed. As an exception to that, Insert
+// operations running on MongoDB versions prior to 2.6 will report the last
+// error only due to a limitation in the wire protocol.
+func (b *Bulk) Run() (*BulkResult, error) {
+	var result BulkResult
+	var berr BulkError
+	var failed bool
+	for i := range b.actions {
+		action := &b.actions[i]
+		var ok bool
+		switch action.op {
+		case bulkInsert:
+			ok = b.runInsert(action, &result, &berr)
+		case bulkUpdate:
+			ok = b.runUpdate(action, &result, &berr)
+		case bulkRemove:
+			ok = b.runRemove(action, &result, &berr)
+		default:
+			panic("unknown bulk operation")
+		}
+		if !ok {
+			failed = true
+			if b.ordered {
+				break
+			}
+		}
+	}
+	if failed {
+		sort.Sort(bulkErrorCases(berr.ecases))
+		return nil, &berr
+	}
+	return &result, nil
+}
+
+func (b *Bulk) runInsert(action *bulkAction, result *BulkResult, berr *BulkError) bool {
+	op := &insertOp{b.c.FullName, action.docs, 0}
+	if !b.ordered {
+		op.flags = 1 // ContinueOnError
+	}
+	lerr, err := b.c.writeOp(op, b.ordered)
+	return b.checkSuccess(action, berr, lerr, err)
+}
+
+func (b *Bulk) runUpdate(action *bulkAction, result *BulkResult, berr *BulkError) bool {
+	lerr, err := b.c.writeOp(bulkUpdateOp(action.docs), b.ordered)
+	if lerr != nil {
+		result.Matched += lerr.N
+		result.Modified += lerr.modified
+	}
+	return b.checkSuccess(action, berr, lerr, err)
+}
+
+func (b *Bulk) runRemove(action *bulkAction, result *BulkResult, berr *BulkError) bool {
+	lerr, err := b.c.writeOp(bulkDeleteOp(action.docs), b.ordered)
+	if lerr != nil {
+		result.Matched += lerr.N
+		result.Modified += lerr.modified
+	}
+	return b.checkSuccess(action, berr, lerr, err)
+}
+
+func (b *Bulk) checkSuccess(action *bulkAction, berr *BulkError, lerr *LastError, err error) bool {
+	if lerr != nil && len(lerr.ecases) > 0 {
+		for i := 0; i < len(lerr.ecases); i++ {
+			// Map back from the local error index into the visible one.
+			ecase := lerr.ecases[i]
+			idx := ecase.Index
+			if idx >= 0 {
+				idx = action.idxs[idx]
+			}
+			berr.ecases = append(berr.ecases, BulkErrorCase{idx, ecase.Err})
+		}
+		return false
+	} else if err != nil {
+		for i := 0; i < len(action.idxs); i++ {
+			berr.ecases = append(berr.ecases, BulkErrorCase{action.idxs[i], err})
+		}
+		return false
+	}
+	return true
+}

vendor/gopkg.in/mgo.v2/cluster.go

@@ -0,0 +1,682 @@
+// mgo - MongoDB driver for Go
+//
+// Copyright (c) 2010-2012 - Gustavo Niemeyer <gustavo@niemeyer.net>
+//
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this
+//    list of conditions and the following disclaimer.
+// 2. Redistributions in binary form must reproduce the above copyright notice,
+//    this list of conditions and the following disclaimer in the documentation
+//    and/or other materials provided with the distribution.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+// ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package mgo
+
+import (
+	"errors"
+	"fmt"
+	"net"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+
+	"gopkg.in/mgo.v2/bson"
+)
+
+// ---------------------------------------------------------------------------
+// Mongo cluster encapsulation.
+//
+// A cluster enables the communication with one or more servers participating
+// in a mongo cluster.  This works with individual servers, a replica set,
+// a replica pair, one or multiple mongos routers, etc.
+
+type mongoCluster struct {
+	sync.RWMutex
+	serverSynced sync.Cond
+	userSeeds    []string
+	dynaSeeds    []string
+	servers      mongoServers
+	masters      mongoServers
+	references   int
+	syncing      bool
+	direct       bool
+	failFast     bool
+	syncCount    uint
+	setName      string
+	cachedIndex  map[string]bool
+	sync         chan bool
+	dial         dialer
+}
+
+func newCluster(userSeeds []string, direct, failFast bool, dial dialer, setName string) *mongoCluster {
+	cluster := &mongoCluster{
+		userSeeds:  userSeeds,
+		references: 1,
+		direct:     direct,
+		failFast:   failFast,
+		dial:       dial,
+		setName:    setName,
+	}
+	cluster.serverSynced.L = cluster.RWMutex.RLocker()
+	cluster.sync = make(chan bool, 1)
+	stats.cluster(+1)
+	go cluster.syncServersLoop()
+	return cluster
+}
+
+// Acquire increases the reference count for the cluster.
+func (cluster *mongoCluster) Acquire() {
+	cluster.Lock()
+	cluster.references++
+	debugf("Cluster %p acquired (refs=%d)", cluster, cluster.references)
+	cluster.Unlock()
+}
+
+// Release decreases the reference count for the cluster. Once
+// it reaches zero, all servers will be closed.
+func (cluster *mongoCluster) Release() {
+	cluster.Lock()
+	if cluster.references == 0 {
+		panic("cluster.Release() with references == 0")
+	}
+	cluster.references--
+	debugf("Cluster %p released (refs=%d)", cluster, cluster.references)
+	if cluster.references == 0 {
+		for _, server := range cluster.servers.Slice() {
+			server.Close()
+		}
+		// Wake up the sync loop so it can die.
+		cluster.syncServers()
+		stats.cluster(-1)
+	}
+	cluster.Unlock()
+}
+
+func (cluster *mongoCluster) LiveServers() (servers []string) {
+	cluster.RLock()
+	for _, serv := range cluster.servers.Slice() {
+		servers = append(servers, serv.Addr)
+	}
+	cluster.RUnlock()
+	return servers
+}
+
+func (cluster *mongoCluster) removeServer(server *mongoServer) {
+	cluster.Lock()
+	cluster.masters.Remove(server)
+	other := cluster.servers.Remove(server)
+	cluster.Unlock()
+	if other != nil {
+		other.Close()
+		log("Removed server ", server.Addr, " from cluster.")
+	}
+	server.Close()
+}
+
+type isMasterResult struct {
+	IsMaster       bool
+	Secondary      bool
+	Primary        string
+	Hosts          []string
+	Passives       []string
+	Tags           bson.D
+	Msg            string
+	SetName        string `bson:"setName"`
+	MaxWireVersion int    `bson:"maxWireVersion"`
+}
+
+func (cluster *mongoCluster) isMaster(socket *mongoSocket, result *isMasterResult) error {
+	// Monotonic let's it talk to a slave and still hold the socket.
+	session := newSession(Monotonic, cluster, 10*time.Second)
+	session.setSocket(socket)
+	err := session.Run("ismaster", result)
+	session.Close()
+	return err
+}
+
+type possibleTimeout interface {
+	Timeout() bool
+}
+
+var syncSocketTimeout = 5 * time.Second
+
+func (cluster *mongoCluster) syncServer(server *mongoServer) (info *mongoServerInfo, hosts []string, err error) {
+	var syncTimeout time.Duration
+	if raceDetector {
+		// This variable is only ever touched by tests.
+		globalMutex.Lock()
+		syncTimeout = syncSocketTimeout
+		globalMutex.Unlock()
+	} else {
+		syncTimeout = syncSocketTimeout
+	}
+
+	addr := server.Addr
+	log("SYNC Processing ", addr, "...")
+
+	// Retry a few times to avoid knocking a server down for a hiccup.
+	var result isMasterResult
+	var tryerr error
+	for retry := 0; ; retry++ {
+		if retry == 3 || retry == 1 && cluster.failFast {
+			return nil, nil, tryerr
+		}
+		if retry > 0 {
+			// Don't abuse the server needlessly if there's something actually wrong.
+			if err, ok := tryerr.(possibleTimeout); ok && err.Timeout() {
+				// Give a chance for waiters to timeout as well.
+				cluster.serverSynced.Broadcast()
+			}
+			time.Sleep(syncShortDelay)
+		}
+
+		// It's not clear what would be a good timeout here. Is it
+		// better to wait longer or to retry?
+		socket, _, err := server.AcquireSocket(0, syncTimeout)
+		if err != nil {
+			tryerr = err
+			logf("SYNC Failed to get socket to %s: %v", addr, err)
+			continue
+		}
+		err = cluster.isMaster(socket, &result)
+		socket.Release()
+		if err != nil {
+			tryerr = err
+			logf("SYNC Command 'ismaster' to %s failed: %v", addr, err)
+			continue
+		}
+		debugf("SYNC Result of 'ismaster' from %s: %#v", addr, result)
+		break
+	}
+
+	if cluster.setName != "" && result.SetName != cluster.setName {
+		logf("SYNC Server %s is not a member of replica set %q", addr, cluster.setName)
+		return nil, nil, fmt.Errorf("server %s is not a member of replica set %q", addr, cluster.setName)
+	}
+
+	if result.IsMaster {
+		debugf("SYNC %s is a master.", addr)
+		if !server.info.Master {
+			// Made an incorrect assumption above, so fix stats.
+			stats.conn(-1, false)
+			stats.conn(+1, true)
+		}
+	} else if result.Secondary {
+		debugf("SYNC %s is a slave.", addr)
+	} else if cluster.direct {
+		logf("SYNC %s in unknown state. Pretending it's a slave due to direct connection.", addr)
+	} else {
+		logf("SYNC %s is neither a master nor a slave.", addr)
+		// Let stats track it as whatever was known before.
+		return nil, nil, errors.New(addr + " is not a master nor slave")
+	}
+
+	info = &mongoServerInfo{
+		Master:         result.IsMaster,
+		Mongos:         result.Msg == "isdbgrid",
+		Tags:           result.Tags,
+		SetName:        result.SetName,
+		MaxWireVersion: result.MaxWireVersion,
+	}
+
+	hosts = make([]string, 0, 1+len(result.Hosts)+len(result.Passives))
+	if result.Primary != "" {
+		// First in the list to speed up master discovery.
+		hosts = append(hosts, result.Primary)
+	}
+	hosts = append(hosts, result.Hosts...)
+	hosts = append(hosts, result.Passives...)
+
+	debugf("SYNC %s knows about the following peers: %#v", addr, hosts)
+	return info, hosts, nil
+}
+
+type syncKind bool
+
+const (
+	completeSync syncKind = true
+	partialSync  syncKind = false
+)
+
+func (cluster *mongoCluster) addServer(server *mongoServer, info *mongoServerInfo, syncKind syncKind) {
+	cluster.Lock()
+	current := cluster.servers.Search(server.ResolvedAddr)
+	if current == nil {
+		if syncKind == partialSync {
+			cluster.Unlock()
+			server.Close()
+			log("SYNC Discarding unknown server ", server.Addr, " due to partial sync.")
+			return
+		}
+		cluster.servers.Add(server)
+		if info.Master {
+			cluster.masters.Add(server)
+			log("SYNC Adding ", server.Addr, " to cluster as a master.")
+		} else {
+			log("SYNC Adding ", server.Addr, " to cluster as a slave.")
+		}
+	} else {
+		if server != current {
+			panic("addServer attempting to add duplicated server")
+		}
+		if server.Info().Master != info.Master {
+			if info.Master {
+				log("SYNC Server ", server.Addr, " is now a master.")
+				cluster.masters.Add(server)
+			} else {
+				log("SYNC Server ", server.Addr, " is now a slave.")
+				cluster.masters.Remove(server)
+			}
+		}
+	}
+	server.SetInfo(info)
+	debugf("SYNC Broadcasting availability of server %s", server.Addr)
+	cluster.serverSynced.Broadcast()
+	cluster.Unlock()
+}
+
+func (cluster *mongoCluster) getKnownAddrs() []string {
+	cluster.RLock()
+	max := len(cluster.userSeeds) + len(cluster.dynaSeeds) + cluster.servers.Len()
+	seen := make(map[string]bool, max)
+	known := make([]string, 0, max)
+
+	add := func(addr string) {
+		if _, found := seen[addr]; !found {
+			seen[addr] = true
+			known = append(known, addr)
+		}
+	}
+
+	for _, addr := range cluster.userSeeds {
+		add(addr)
+	}
+	for _, addr := range cluster.dynaSeeds {
+		add(addr)
+	}
+	for _, serv := range cluster.servers.Slice() {
+		add(serv.Addr)
+	}
+	cluster.RUnlock()
+
+	return known
+}
+
+// syncServers injects a value into the cluster.sync channel to force
+// an iteration of the syncServersLoop function.
+func (cluster *mongoCluster) syncServers() {
+	select {
+	case cluster.sync <- true:
+	default:
+	}
+}
+
+// How long to wait for a checkup of the cluster topology if nothing
+// else kicks a synchronization before that.
+const syncServersDelay = 30 * time.Second
+const syncShortDelay = 500 * time.Millisecond
+
+// syncServersLoop loops while the cluster is alive to keep its idea of
+// the server topology up-to-date. It must be called just once from
+// newCluster.  The loop iterates once syncServersDelay has passed, or
+// if somebody injects a value into the cluster.sync channel to force a
+// synchronization.  A loop iteration will contact all servers in
+// parallel, ask them about known peers and their own role within the
+// cluster, and then attempt to do the same with all the peers
+// retrieved.
+func (cluster *mongoCluster) syncServersLoop() {
+	for {
+		debugf("SYNC Cluster %p is starting a sync loop iteration.", cluster)
+
+		cluster.Lock()
+		if cluster.references == 0 {
+			cluster.Unlock()
+			break
+		}
+		cluster.references++ // Keep alive while syncing.
+		direct := cluster.direct
+		cluster.Unlock()
+
+		cluster.syncServersIteration(direct)
+
+		// We just synchronized, so consume any outstanding requests.
+		select {
+		case <-cluster.sync:
+		default:
+		}
+
+		cluster.Release()
+
+		// Hold off before allowing another sync. No point in
+		// burning CPU looking for down servers.
+		if !cluster.failFast {
+			time.Sleep(syncShortDelay)
+		}
+
+		cluster.Lock()
+		if cluster.references == 0 {
+			cluster.Unlock()
+			break
+		}
+		cluster.syncCount++
+		// Poke all waiters so they have a chance to timeout or
+		// restart syncing if they wish to.
+		cluster.serverSynced.Broadcast()
+		// Check if we have to restart immediately either way.
+		restart := !direct && cluster.masters.Empty() || cluster.servers.Empty()
+		cluster.Unlock()
+
+		if restart {
+			log("SYNC No masters found. Will synchronize again.")
+			time.Sleep(syncShortDelay)
+			continue
+		}
+
+		debugf("SYNC Cluster %p waiting for next requested or scheduled sync.", cluster)
+
+		// Hold off until somebody explicitly requests a synchronization
+		// or it's time to check for a cluster topology change again.
+		select {
+		case <-cluster.sync:
+		case <-time.After(syncServersDelay):
+		}
+	}
+	debugf("SYNC Cluster %p is stopping its sync loop.", cluster)
+}
+
+func (cluster *mongoCluster) server(addr string, tcpaddr *net.TCPAddr) *mongoServer {
+	cluster.RLock()
+	server := cluster.servers.Search(tcpaddr.String())
+	cluster.RUnlock()
+	if server != nil {
+		return server
+	}
+	return newServer(addr, tcpaddr, cluster.sync, cluster.dial)
+}
+
+func resolveAddr(addr string) (*net.TCPAddr, error) {
+	// Simple cases that do not need actual resolution. Works with IPv4 and v6.
+	if host, port, err := net.SplitHostPort(addr); err == nil {
+		if port, _ := strconv.Atoi(port); port > 0 {
+			zone := ""
+			if i := strings.LastIndex(host, "%"); i >= 0 {
+				zone = host[i+1:]
+				host = host[:i]
+			}
+			ip := net.ParseIP(host)
+			if ip != nil {
+				return &net.TCPAddr{IP: ip, Port: port, Zone: zone}, nil
+			}
+		}
+	}
+
+	// Attempt to resolve IPv4 and v6 concurrently.
+	addrChan := make(chan *net.TCPAddr, 2)
+	for _, network := range []string{"udp4", "udp6"} {
+		network := network
+		go func() {
+			// The unfortunate UDP dialing hack allows having a timeout on address resolution.
+			conn, err := net.DialTimeout(network, addr, 10*time.Second)
+			if err != nil {
+				addrChan <- nil
+			} else {
+				addrChan <- (*net.TCPAddr)(conn.RemoteAddr().(*net.UDPAddr))
+				conn.Close()
+			}
+		}()
+	}
+
+	// Wait for the result of IPv4 and v6 resolution. Use IPv4 if available.
+	tcpaddr := <-addrChan
+	if tcpaddr == nil || len(tcpaddr.IP) != 4 {
+		var timeout <-chan time.Time
+		if tcpaddr != nil {
+			// Don't wait too long if an IPv6 address is known.
+			timeout = time.After(50 * time.Millisecond)
+		}
+		select {
+		case <-timeout:
+		case tcpaddr2 := <-addrChan:
+			if tcpaddr == nil || tcpaddr2 != nil {
+				// It's an IPv4 address or the only known address. Use it.
+				tcpaddr = tcpaddr2
+			}
+		}
+	}
+
+	if tcpaddr == nil {
+		log("SYNC Failed to resolve server address: ", addr)
+		return nil, errors.New("failed to resolve server address: " + addr)
+	}
+	if tcpaddr.String() != addr {
+		debug("SYNC Address ", addr, " resolved as ", tcpaddr.String())
+	}
+	return tcpaddr, nil
+}
+
+type pendingAdd struct {
+	server *mongoServer
+	info   *mongoServerInfo
+}
+
+func (cluster *mongoCluster) syncServersIteration(direct bool) {
+	log("SYNC Starting full topology synchronization...")
+
+	var wg sync.WaitGroup
+	var m sync.Mutex
+	notYetAdded := make(map[string]pendingAdd)
+	addIfFound := make(map[string]bool)
+	seen := make(map[string]bool)
+	syncKind := partialSync
+
+	var spawnSync func(addr string, byMaster bool)
+	spawnSync = func(addr string, byMaster bool) {
+		wg.Add(1)
+		go func() {
+			defer wg.Done()
+
+			tcpaddr, err := resolveAddr(addr)
+			if err != nil {
+				log("SYNC Failed to start sync of ", addr, ": ", err.Error())
+				return
+			}
+			resolvedAddr := tcpaddr.String()
+
+			m.Lock()
+			if byMaster {
+				if pending, ok := notYetAdded[resolvedAddr]; ok {
+					delete(notYetAdded, resolvedAddr)
+					m.Unlock()
+					cluster.addServer(pending.server, pending.info, completeSync)
+					return
+				}
+				addIfFound[resolvedAddr] = true
+			}
+			if seen[resolvedAddr] {
+				m.Unlock()
+				return
+			}
+			seen[resolvedAddr] = true
+			m.Unlock()
+
+			server := cluster.server(addr, tcpaddr)
+			info, hosts, err := cluster.syncServer(server)
+			if err != nil {
+				cluster.removeServer(server)
+				return
+			}
+
+			m.Lock()
+			add := direct || info.Master || addIfFound[resolvedAddr]
+			if add {
+				syncKind = completeSync
+			} else {
+				notYetAdded[resolvedAddr] = pendingAdd{server, info}
+			}
+			m.Unlock()
+			if add {
+				cluster.addServer(server, info, completeSync)
+			}
+			if !direct {
+				for _, addr := range hosts {
+					spawnSync(addr, info.Master)
+				}
+			}
+		}()
+	}
+
+	knownAddrs := cluster.getKnownAddrs()
+	for _, addr := range knownAddrs {
+		spawnSync(addr, false)
+	}
+	wg.Wait()
+
+	if syncKind == completeSync {
+		logf("SYNC Synchronization was complete (got data from primary).")
+		for _, pending := range notYetAdded {
+			cluster.removeServer(pending.server)
+		}
+	} else {
+		logf("SYNC Synchronization was partial (cannot talk to primary).")
+		for _, pending := range notYetAdded {
+			cluster.addServer(pending.server, pending.info, partialSync)
+		}
+	}
+
+	cluster.Lock()
+	mastersLen := cluster.masters.Len()
+	logf("SYNC Synchronization completed: %d master(s) and %d slave(s) alive.", mastersLen, cluster.servers.Len()-mastersLen)
+
+	// Update dynamic seeds, but only if we have any good servers. Otherwise,
+	// leave them alone for better chances of a successful sync in the future.
+	if syncKind == completeSync {
+		dynaSeeds := make([]string, cluster.servers.Len())
+		for i, server := range cluster.servers.Slice() {
+			dynaSeeds[i] = server.Addr
+		}
+		cluster.dynaSeeds = dynaSeeds
+		debugf("SYNC New dynamic seeds: %#v\n", dynaSeeds)
+	}
+	cluster.Unlock()
+}
+
+// AcquireSocket returns a socket to a server in the cluster.  If slaveOk is
+// true, it will attempt to return a socket to a slave server.  If it is
+// false, the socket will necessarily be to a master server.
+func (cluster *mongoCluster) AcquireSocket(mode Mode, slaveOk bool, syncTimeout time.Duration, socketTimeout time.Duration, serverTags []bson.D, poolLimit int) (s *mongoSocket, err error) {
+	var started time.Time
+	var syncCount uint
+	warnedLimit := false
+	for {
+		cluster.RLock()
+		for {
+			mastersLen := cluster.masters.Len()
+			slavesLen := cluster.servers.Len() - mastersLen
+			debugf("Cluster has %d known masters and %d known slaves.", mastersLen, slavesLen)
+			if mastersLen > 0 && !(slaveOk && mode == Secondary) || slavesLen > 0 && slaveOk {
+				break
+			}
+			if mastersLen > 0 && mode == Secondary && cluster.masters.HasMongos() {
+				break
+			}
+			if started.IsZero() {
+				// Initialize after fast path above.
+				started = time.Now()
+				syncCount = cluster.syncCount
+			} else if syncTimeout != 0 && started.Before(time.Now().Add(-syncTimeout)) || cluster.failFast && cluster.syncCount != syncCount {
+				cluster.RUnlock()
+				return nil, errors.New("no reachable servers")
+			}
+			log("Waiting for servers to synchronize...")
+			cluster.syncServers()
+
+			// Remember: this will release and reacquire the lock.
+			cluster.serverSynced.Wait()
+		}
+
+		var server *mongoServer
+		if slaveOk {
+			server = cluster.servers.BestFit(mode, serverTags)
+		} else {
+			server = cluster.masters.BestFit(mode, nil)
+		}
+		cluster.RUnlock()
+
+		if server == nil {
+			// Must have failed the requested tags. Sleep to avoid spinning.
+			time.Sleep(1e8)
+			continue
+		}
+
+		s, abended, err := server.AcquireSocket(poolLimit, socketTimeout)
+		if err == errPoolLimit {
+			if !warnedLimit {
+				warnedLimit = true
+				log("WARNING: Per-server connection limit reached.")
+			}
+			time.Sleep(100 * time.Millisecond)
+			continue
+		}
+		if err != nil {
+			cluster.removeServer(server)
+			cluster.syncServers()
+			continue
+		}
+		if abended && !slaveOk {
+			var result isMasterResult
+			err := cluster.isMaster(s, &result)
+			if err != nil || !result.IsMaster {
+				logf("Cannot confirm server %s as master (%v)", server.Addr, err)
+				s.Release()
+				cluster.syncServers()
+				time.Sleep(100 * time.Millisecond)
+				continue
+			}
+		}
+		return s, nil
+	}
+	panic("unreached")
+}
+
+func (cluster *mongoCluster) CacheIndex(cacheKey string, exists bool) {
+	cluster.Lock()
+	if cluster.cachedIndex == nil {
+		cluster.cachedIndex = make(map[string]bool)
+	}
+	if exists {
+		cluster.cachedIndex[cacheKey] = true
+	} else {
+		delete(cluster.cachedIndex, cacheKey)
+	}
+	cluster.Unlock()
+}
+
+func (cluster *mongoCluster) HasCachedIndex(cacheKey string) (result bool) {
+	cluster.RLock()
+	if cluster.cachedIndex != nil {
+		result = cluster.cachedIndex[cacheKey]
+	}
+	cluster.RUnlock()
+	return
+}
+
+func (cluster *mongoCluster) ResetIndexCache() {
+	cluster.Lock()
+	cluster.cachedIndex = make(map[string]bool)
+	cluster.Unlock()
+}

vendor/gopkg.in/mgo.v2/doc.go

@@ -0,0 +1,34 @@
+// Package mgo offers a rich MongoDB driver for Go.
+//
+// #########################################################
+//
+// THIS DRIVER IS UNMAINTAINED! See here for details:
+//
+// https://github.com/go-mgo/mgo/blob/v2-unstable/README.md
+//
+// #########################################################
+//
+// Usage of the driver revolves around the concept of sessions.  To
+// get started, obtain a session using the Dial function:
+//
+//     session, err := mgo.Dial(url)
+//
+// This will establish one or more connections with the cluster of
+// servers defined by the url parameter.  From then on, the cluster
+// may be queried with multiple consistency rules (see SetMode) and
+// documents retrieved with statements such as:
+//
+//     c := session.DB(database).C(collection)
+//     err := c.Find(query).One(&result)
+//
+// New sessions are typically created by calling session.Copy on the
+// initial session obtained at dial time. These new sessions will share
+// the same cluster information and connection pool, and may be easily
+// handed into other methods and functions for organizing logic.
+// Every session created must have its Close method called at the end
+// of its life time, so its resources may be put back in the pool or
+// collected, depending on the case.
+//
+// For more details, see the documentation for the types and methods.
+//
+package mgo

vendor/gopkg.in/mgo.v2/gridfs.go

@@ -0,0 +1,761 @@
+// mgo - MongoDB driver for Go
+//
+// Copyright (c) 2010-2012 - Gustavo Niemeyer <gustavo@niemeyer.net>
+//
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this
+//    list of conditions and the following disclaimer.
+// 2. Redistributions in binary form must reproduce the above copyright notice,
+//    this list of conditions and the following disclaimer in the documentation
+//    and/or other materials provided with the distribution.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+// ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package mgo
+
+import (
+	"crypto/md5"
+	"encoding/hex"
+	"errors"
+	"hash"
+	"io"
+	"os"
+	"sync"
+	"time"
+
+	"gopkg.in/mgo.v2/bson"
+)
+
+type GridFS struct {
+	Files  *Collection
+	Chunks *Collection
+}
+
+type gfsFileMode int
+
+const (
+	gfsClosed  gfsFileMode = 0
+	gfsReading gfsFileMode = 1
+	gfsWriting gfsFileMode = 2
+)
+
+type GridFile struct {
+	m    sync.Mutex
+	c    sync.Cond
+	gfs  *GridFS
+	mode gfsFileMode
+	err  error
+
+	chunk  int
+	offset int64
+
+	wpending int
+	wbuf     []byte
+	wsum     hash.Hash
+
+	rbuf   []byte
+	rcache *gfsCachedChunk
+
+	doc gfsFile
+}
+
+type gfsFile struct {
+	Id          interface{} "_id"
+	ChunkSize   int         "chunkSize"
+	UploadDate  time.Time   "uploadDate"
+	Length      int64       ",minsize"
+	MD5         string
+	Filename    string    ",omitempty"
+	ContentType string    "contentType,omitempty"
+	Metadata    *bson.Raw ",omitempty"
+}
+
+type gfsChunk struct {
+	Id      interface{} "_id"
+	FilesId interface{} "files_id"
+	N       int
+	Data    []byte
+}
+
+type gfsCachedChunk struct {
+	wait sync.Mutex
+	n    int
+	data []byte
+	err  error
+}
+
+func newGridFS(db *Database, prefix string) *GridFS {
+	return &GridFS{db.C(prefix + ".files"), db.C(prefix + ".chunks")}
+}
+
+func (gfs *GridFS) newFile() *GridFile {
+	file := &GridFile{gfs: gfs}
+	file.c.L = &file.m
+	//runtime.SetFinalizer(file, finalizeFile)
+	return file
+}
+
+func finalizeFile(file *GridFile) {
+	file.Close()
+}
+
+// Create creates a new file with the provided name in the GridFS.  If the file
+// name already exists, a new version will be inserted with an up-to-date
+// uploadDate that will cause it to be atomically visible to the Open and
+// OpenId methods.  If the file name is not important, an empty name may be
+// provided and the file Id used instead.
+//
+// It's important to Close files whether they are being written to
+// or read from, and to check the err result to ensure the operation
+// completed successfully.
+//
+// A simple example inserting a new file:
+//
+//     func check(err error) {
+//         if err != nil {
+//             panic(err.String())
+//         }
+//     }
+//     file, err := db.GridFS("fs").Create("myfile.txt")
+//     check(err)
+//     n, err := file.Write([]byte("Hello world!"))
+//     check(err)
+//     err = file.Close()
+//     check(err)
+//     fmt.Printf("%d bytes written\n", n)
+//
+// The io.Writer interface is implemented by *GridFile and may be used to
+// help on the file creation.  For example:
+//
+//     file, err := db.GridFS("fs").Create("myfile.txt")
+//     check(err)
+//     messages, err := os.Open("/var/log/messages")
+//     check(err)
+//     defer messages.Close()
+//     err = io.Copy(file, messages)
+//     check(err)
+//     err = file.Close()
+//     check(err)
+//
+func (gfs *GridFS) Create(name string) (file *GridFile, err error) {
+	file = gfs.newFile()
+	file.mode = gfsWriting
+	file.wsum = md5.New()
+	file.doc = gfsFile{Id: bson.NewObjectId(), ChunkSize: 255 * 1024, Filename: name}
+	return
+}
+
+// OpenId returns the file with the provided id, for reading.
+// If the file isn't found, err will be set to mgo.ErrNotFound.
+//
+// It's important to Close files whether they are being written to
+// or read from, and to check the err result to ensure the operation
+// completed successfully.
+//
+// The following example will print the first 8192 bytes from the file:
+//
+//     func check(err error) {
+//         if err != nil {
+//             panic(err.String())
+//         }
+//     }
+//     file, err := db.GridFS("fs").OpenId(objid)
+//     check(err)
+//     b := make([]byte, 8192)
+//     n, err := file.Read(b)
+//     check(err)
+//     fmt.Println(string(b))
+//     check(err)
+//     err = file.Close()
+//     check(err)
+//     fmt.Printf("%d bytes read\n", n)
+//
+// The io.Reader interface is implemented by *GridFile and may be used to
+// deal with it.  As an example, the following snippet will dump the whole
+// file into the standard output:
+//
+//     file, err := db.GridFS("fs").OpenId(objid)
+//     check(err)
+//     err = io.Copy(os.Stdout, file)
+//     check(err)
+//     err = file.Close()
+//     check(err)
+//
+func (gfs *GridFS) OpenId(id interface{}) (file *GridFile, err error) {
+	var doc gfsFile
+	err = gfs.Files.Find(bson.M{"_id": id}).One(&doc)
+	if err != nil {
+		return
+	}
+	file = gfs.newFile()
+	file.mode = gfsReading
+	file.doc = doc
+	return
+}
+
+// Open returns the most recently uploaded file with the provided
+// name, for reading. If the file isn't found, err will be set
+// to mgo.ErrNotFound.
+//
+// It's important to Close files whether they are being written to
+// or read from, and to check the err result to ensure the operation
+// completed successfully.
+//
+// The following example will print the first 8192 bytes from the file:
+//
+//     file, err := db.GridFS("fs").Open("myfile.txt")
+//     check(err)
+//     b := make([]byte, 8192)
+//     n, err := file.Read(b)
+//     check(err)
+//     fmt.Println(string(b))
+//     check(err)
+//     err = file.Close()
+//     check(err)
+//     fmt.Printf("%d bytes read\n", n)
+//
+// The io.Reader interface is implemented by *GridFile and may be used to
+// deal with it.  As an example, the following snippet will dump the whole
+// file into the standard output:
+//
+//     file, err := db.GridFS("fs").Open("myfile.txt")
+//     check(err)
+//     err = io.Copy(os.Stdout, file)
+//     check(err)
+//     err = file.Close()
+//     check(err)
+//
+func (gfs *GridFS) Open(name string) (file *GridFile, err error) {
+	var doc gfsFile
+	err = gfs.Files.Find(bson.M{"filename": name}).Sort("-uploadDate").One(&doc)
+	if err != nil {
+		return
+	}
+	file = gfs.newFile()
+	file.mode = gfsReading
+	file.doc = doc
+	return
+}
+
+// OpenNext opens the next file from iter for reading, sets *file to it,
+// and returns true on the success case. If no more documents are available
+// on iter or an error occurred, *file is set to nil and the result is false.
+// Errors will be available via iter.Err().
+//
+// The iter parameter must be an iterator on the GridFS files collection.
+// Using the GridFS.Find method is an easy way to obtain such an iterator,
+// but any iterator on the collection will work.
+//
+// If the provided *file is non-nil, OpenNext will close it before attempting
+// to iterate to the next element. This means that in a loop one only
+// has to worry about closing files when breaking out of the loop early
+// (break, return, or panic).
+//
+// For example:
+//
+//     gfs := db.GridFS("fs")
+//     query := gfs.Find(nil).Sort("filename")
+//     iter := query.Iter()
+//     var f *mgo.GridFile
+//     for gfs.OpenNext(iter, &f) {
+//         fmt.Printf("Filename: %s\n", f.Name())
+//     }
+//     if iter.Close() != nil {
+//         panic(iter.Close())
+//     }
+//
+func (gfs *GridFS) OpenNext(iter *Iter, file **GridFile) bool {
+	if *file != nil {
+		// Ignoring the error here shouldn't be a big deal
+		// as we're reading the file and the loop iteration
+		// for this file is finished.
+		_ = (*file).Close()
+	}
+	var doc gfsFile
+	if !iter.Next(&doc) {
+		*file = nil
+		return false
+	}
+	f := gfs.newFile()
+	f.mode = gfsReading
+	f.doc = doc
+	*file = f
+	return true
+}
+
+// Find runs query on GridFS's files collection and returns
+// the resulting Query.
+//
+// This logic:
+//
+//     gfs := db.GridFS("fs")
+//     iter := gfs.Find(nil).Iter()
+//
+// Is equivalent to:
+//
+//     files := db.C("fs" + ".files")
+//     iter := files.Find(nil).Iter()
+//
+func (gfs *GridFS) Find(query interface{}) *Query {
+	return gfs.Files.Find(query)
+}
+
+// RemoveId deletes the file with the provided id from the GridFS.
+func (gfs *GridFS) RemoveId(id interface{}) error {
+	err := gfs.Files.Remove(bson.M{"_id": id})
+	if err != nil {
+		return err
+	}
+	_, err = gfs.Chunks.RemoveAll(bson.D{{"files_id", id}})
+	return err
+}
+
+type gfsDocId struct {
+	Id interface{} "_id"
+}
+
+// Remove deletes all files with the provided name from the GridFS.
+func (gfs *GridFS) Remove(name string) (err error) {
+	iter := gfs.Files.Find(bson.M{"filename": name}).Select(bson.M{"_id": 1}).Iter()
+	var doc gfsDocId
+	for iter.Next(&doc) {
+		if e := gfs.RemoveId(doc.Id); e != nil {
+			err = e
+		}
+	}
+	if err == nil {
+		err = iter.Close()
+	}
+	return err
+}
+
+func (file *GridFile) assertMode(mode gfsFileMode) {
+	switch file.mode {
+	case mode:
+		return
+	case gfsWriting:
+		panic("GridFile is open for writing")
+	case gfsReading:
+		panic("GridFile is open for reading")
+	case gfsClosed:
+		panic("GridFile is closed")
+	default:
+		panic("internal error: missing GridFile mode")
+	}
+}
+
+// SetChunkSize sets size of saved chunks.  Once the file is written to, it
+// will be split in blocks of that size and each block saved into an
+// independent chunk document.  The default chunk size is 255kb.
+//
+// It is a runtime error to call this function once the file has started
+// being written to.
+func (file *GridFile) SetChunkSize(bytes int) {
+	file.assertMode(gfsWriting)
+	debugf("GridFile %p: setting chunk size to %d", file, bytes)
+	file.m.Lock()
+	file.doc.ChunkSize = bytes
+	file.m.Unlock()
+}
+
+// Id returns the current file Id.
+func (file *GridFile) Id() interface{} {
+	return file.doc.Id
+}
+
+// SetId changes the current file Id.
+//
+// It is a runtime error to call this function once the file has started
+// being written to, or when the file is not open for writing.
+func (file *GridFile) SetId(id interface{}) {
+	file.assertMode(gfsWriting)
+	file.m.Lock()
+	file.doc.Id = id
+	file.m.Unlock()
+}
+
+// Name returns the optional file name.  An empty string will be returned
+// in case it is unset.
+func (file *GridFile) Name() string {
+	return file.doc.Filename
+}
+
+// SetName changes the optional file name.  An empty string may be used to
+// unset it.
+//
+// It is a runtime error to call this function when the file is not open
+// for writing.
+func (file *GridFile) SetName(name string) {
+	file.assertMode(gfsWriting)
+	file.m.Lock()
+	file.doc.Filename = name
+	file.m.Unlock()
+}
+
+// ContentType returns the optional file content type.  An empty string will be
+// returned in case it is unset.
+func (file *GridFile) ContentType() string {
+	return file.doc.ContentType
+}
+
+// ContentType changes the optional file content type.  An empty string may be
+// used to unset it.
+//
+// It is a runtime error to call this function when the file is not open
+// for writing.
+func (file *GridFile) SetContentType(ctype string) {
+	file.assertMode(gfsWriting)
+	file.m.Lock()
+	file.doc.ContentType = ctype
+	file.m.Unlock()
+}
+
+// GetMeta unmarshals the optional "metadata" field associated with the
+// file into the result parameter. The meaning of keys under that field
+// is user-defined. For example:
+//
+//     result := struct{ INode int }{}
+//     err = file.GetMeta(&result)
+//     if err != nil {
+//         panic(err.String())
+//     }
+//     fmt.Printf("inode: %d\n", result.INode)
+//
+func (file *GridFile) GetMeta(result interface{}) (err error) {
+	file.m.Lock()
+	if file.doc.Metadata != nil {
+		err = bson.Unmarshal(file.doc.Metadata.Data, result)
+	}
+	file.m.Unlock()
+	return
+}
+
+// SetMeta changes the optional "metadata" field associated with the
+// file. The meaning of keys under that field is user-defined.
+// For example:
+//
+//     file.SetMeta(bson.M{"inode": inode})
+//
+// It is a runtime error to call this function when the file is not open
+// for writing.
+func (file *GridFile) SetMeta(metadata interface{}) {
+	file.assertMode(gfsWriting)
+	data, err := bson.Marshal(metadata)
+	file.m.Lock()
+	if err != nil && file.err == nil {
+		file.err = err
+	} else {
+		file.doc.Metadata = &bson.Raw{Data: data}
+	}
+	file.m.Unlock()
+}
+
+// Size returns the file size in bytes.
+func (file *GridFile) Size() (bytes int64) {
+	file.m.Lock()
+	bytes = file.doc.Length
+	file.m.Unlock()
+	return
+}
+
+// MD5 returns the file MD5 as a hex-encoded string.
+func (file *GridFile) MD5() (md5 string) {
+	return file.doc.MD5
+}
+
+// UploadDate returns the file upload time.
+func (file *GridFile) UploadDate() time.Time {
+	return file.doc.UploadDate
+}
+
+// SetUploadDate changes the file upload time.
+//
+// It is a runtime error to call this function when the file is not open
+// for writing.
+func (file *GridFile) SetUploadDate(t time.Time) {
+	file.assertMode(gfsWriting)
+	file.m.Lock()
+	file.doc.UploadDate = t
+	file.m.Unlock()
+}
+
+// Close flushes any pending changes in case the file is being written
+// to, waits for any background operations to finish, and closes the file.
+//
+// It's important to Close files whether they are being written to
+// or read from, and to check the err result to ensure the operation
+// completed successfully.
+func (file *GridFile) Close() (err error) {
+	file.m.Lock()
+	defer file.m.Unlock()
+	if file.mode == gfsWriting {
+		if len(file.wbuf) > 0 && file.err == nil {
+			file.insertChunk(file.wbuf)
+			file.wbuf = file.wbuf[0:0]
+		}
+		file.completeWrite()
+	} else if file.mode == gfsReading && file.rcache != nil {
+		file.rcache.wait.Lock()
+		file.rcache = nil
+	}
+	file.mode = gfsClosed
+	debugf("GridFile %p: closed", file)
+	return file.err
+}
+
+func (file *GridFile) completeWrite() {
+	for file.wpending > 0 {
+		debugf("GridFile %p: waiting for %d pending chunks to complete file write", file, file.wpending)
+		file.c.Wait()
+	}
+	if file.err == nil {
+		hexsum := hex.EncodeToString(file.wsum.Sum(nil))
+		if file.doc.UploadDate.IsZero() {
+			file.doc.UploadDate = bson.Now()
+		}
+		file.doc.MD5 = hexsum
+		file.err = file.gfs.Files.Insert(file.doc)
+	}
+	if file.err != nil {
+		file.gfs.Chunks.RemoveAll(bson.D{{"files_id", file.doc.Id}})
+	}
+	if file.err == nil {
+		index := Index{
+			Key:    []string{"files_id", "n"},
+			Unique: true,
+		}
+		file.err = file.gfs.Chunks.EnsureIndex(index)
+	}
+}
+
+// Abort cancels an in-progress write, preventing the file from being
+// automically created and ensuring previously written chunks are
+// removed when the file is closed.
+//
+// It is a runtime error to call Abort when the file was not opened
+// for writing.
+func (file *GridFile) Abort() {
+	if file.mode != gfsWriting {
+		panic("file.Abort must be called on file opened for writing")
+	}
+	file.err = errors.New("write aborted")
+}
+
+// Write writes the provided data to the file and returns the
+// number of bytes written and an error in case something
+// wrong happened.
+//
+// The file will internally cache the data so that all but the last
+// chunk sent to the database have the size defined by SetChunkSize.
+// This also means that errors may be deferred until a future call
+// to Write or Close.
+//
+// The parameters and behavior of this function turn the file
+// into an io.Writer.
+func (file *GridFile) Write(data []byte) (n int, err error) {
+	file.assertMode(gfsWriting)
+	file.m.Lock()
+	debugf("GridFile %p: writing %d bytes", file, len(data))
+	defer file.m.Unlock()
+
+	if file.err != nil {
+		return 0, file.err
+	}
+
+	n = len(data)
+	file.doc.Length += int64(n)
+	chunkSize := file.doc.ChunkSize
+
+	if len(file.wbuf)+len(data) < chunkSize {
+		file.wbuf = append(file.wbuf, data...)
+		return
+	}
+
+	// First, flush file.wbuf complementing with data.
+	if len(file.wbuf) > 0 {
+		missing := chunkSize - len(file.wbuf)
+		if missing > len(data) {
+			missing = len(data)
+		}
+		file.wbuf = append(file.wbuf, data[:missing]...)
+		data = data[missing:]
+		file.insertChunk(file.wbuf)
+		file.wbuf = file.wbuf[0:0]
+	}
+
+	// Then, flush all chunks from data without copying.
+	for len(data) > chunkSize {
+		size := chunkSize
+		if size > len(data) {
+			size = len(data)
+		}
+		file.insertChunk(data[:size])
+		data = data[size:]
+	}
+
+	// And append the rest for a future call.
+	file.wbuf = append(file.wbuf, data...)
+
+	return n, file.err
+}
+
+func (file *GridFile) insertChunk(data []byte) {
+	n := file.chunk
+	file.chunk++
+	debugf("GridFile %p: adding to checksum: %q", file, string(data))
+	file.wsum.Write(data)
+
+	for file.doc.ChunkSize*file.wpending >= 1024*1024 {
+		// Hold on.. we got a MB pending.
+		file.c.Wait()
+		if file.err != nil {
+			return
+		}
+	}
+
+	file.wpending++
+
+	debugf("GridFile %p: inserting chunk %d with %d bytes", file, n, len(data))
+
+	// We may not own the memory of data, so rather than
+	// simply copying it, we'll marshal the document ahead of time.
+	data, err := bson.Marshal(gfsChunk{bson.NewObjectId(), file.doc.Id, n, data})
+	if err != nil {
+		file.err = err
+		return
+	}
+
+	go func() {
+		err := file.gfs.Chunks.Insert(bson.Raw{Data: data})
+		file.m.Lock()
+		file.wpending--
+		if err != nil && file.err == nil {
+			file.err = err
+		}
+		file.c.Broadcast()
+		file.m.Unlock()
+	}()
+}
+
+// Seek sets the offset for the next Read or Write on file to
+// offset, interpreted according to whence: 0 means relative to
+// the origin of the file, 1 means relative to the current offset,
+// and 2 means relative to the end. It returns the new offset and
+// an error, if any.
+func (file *GridFile) Seek(offset int64, whence int) (pos int64, err error) {
+	file.m.Lock()
+	debugf("GridFile %p: seeking for %d (whence=%d)", file, offset, whence)
+	defer file.m.Unlock()
+	switch whence {
+	case os.SEEK_SET:
+	case os.SEEK_CUR:
+		offset += file.offset
+	case os.SEEK_END:
+		offset += file.doc.Length
+	default:
+		panic("unsupported whence value")
+	}
+	if offset > file.doc.Length {
+		return file.offset, errors.New("seek past end of file")
+	}
+	if offset == file.doc.Length {
+		// If we're seeking to the end of the file,
+		// no need to read anything. This enables
+		// a client to find the size of the file using only the
+		// io.ReadSeeker interface with low overhead.
+		file.offset = offset
+		return file.offset, nil
+	}
+	chunk := int(offset / int64(file.doc.ChunkSize))
+	if chunk+1 == file.chunk && offset >= file.offset {
+		file.rbuf = file.rbuf[int(offset-file.offset):]
+		file.offset = offset
+		return file.offset, nil
+	}
+	file.offset = offset
+	file.chunk = chunk
+	file.rbuf = nil
+	file.rbuf, err = file.getChunk()
+	if err == nil {
+		file.rbuf = file.rbuf[int(file.offset-int64(chunk)*int64(file.doc.ChunkSize)):]
+	}
+	return file.offset, err
+}
+
+// Read reads into b the next available data from the file and
+// returns the number of bytes written and an error in case
+// something wrong happened.  At the end of the file, n will
+// be zero and err will be set to io.EOF.
+//
+// The parameters and behavior of this function turn the file
+// into an io.Reader.
+func (file *GridFile) Read(b []byte) (n int, err error) {
+	file.assertMode(gfsReading)
+	file.m.Lock()
+	debugf("GridFile %p: reading at offset %d into buffer of length %d", file, file.offset, len(b))
+	defer file.m.Unlock()
+	if file.offset == file.doc.Length {
+		return 0, io.EOF
+	}
+	for err == nil {
+		i := copy(b, file.rbuf)
+		n += i
+		file.offset += int64(i)
+		file.rbuf = file.rbuf[i:]
+		if i == len(b) || file.offset == file.doc.Length {
+			break
+		}
+		b = b[i:]
+		file.rbuf, err = file.getChunk()
+	}
+	return n, err
+}
+
+func (file *GridFile) getChunk() (data []byte, err error) {
+	cache := file.rcache
+	file.rcache = nil
+	if cache != nil && cache.n == file.chunk {
+		debugf("GridFile %p: Getting chunk %d from cache", file, file.chunk)
+		cache.wait.Lock()
+		data, err = cache.data, cache.err
+	} else {
+		debugf("GridFile %p: Fetching chunk %d", file, file.chunk)
+		var doc gfsChunk
+		err = file.gfs.Chunks.Find(bson.D{{"files_id", file.doc.Id}, {"n", file.chunk}}).One(&doc)
+		data = doc.Data
+	}
+	file.chunk++
+	if int64(file.chunk)*int64(file.doc.ChunkSize) < file.doc.Length {
+		// Read the next one in background.
+		cache = &gfsCachedChunk{n: file.chunk}
+		cache.wait.Lock()
+		debugf("GridFile %p: Scheduling chunk %d for background caching", file, file.chunk)
+		// Clone the session to avoid having it closed in between.
+		chunks := file.gfs.Chunks
+		session := chunks.Database.Session.Clone()
+		go func(id interface{}, n int) {
+			defer session.Close()
+			chunks = chunks.With(session)
+			var doc gfsChunk
+			cache.err = chunks.Find(bson.D{{"files_id", id}, {"n", n}}).One(&doc)
+			cache.data = doc.Data
+			cache.wait.Unlock()
+		}(file.doc.Id, file.chunk)
+		file.rcache = cache
+	}
+	debugf("Returning err: %#v", err)
+	return
+}

vendor/gopkg.in/mgo.v2/internal/json/LICENSE

@@ -0,0 +1,27 @@
+Copyright (c) 2012 The Go Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/gopkg.in/mgo.v2/internal/json/extension.go

@@ -0,0 +1,95 @@
+package json
+
+import (
+	"reflect"
+)
+
+// Extension holds a set of additional rules to be used when unmarshaling
+// strict JSON or JSON-like content.
+type Extension struct {
+	funcs  map[string]funcExt
+	consts map[string]interface{}
+	keyed  map[string]func([]byte) (interface{}, error)
+	encode map[reflect.Type]func(v interface{}) ([]byte, error)
+
+	unquotedKeys   bool
+	trailingCommas bool
+}
+
+type funcExt struct {
+	key  string
+	args []string
+}
+
+// Extend changes the decoder behavior to consider the provided extension.
+func (dec *Decoder) Extend(ext *Extension) { dec.d.ext = *ext }
+
+// Extend changes the encoder behavior to consider the provided extension.
+func (enc *Encoder) Extend(ext *Extension) { enc.ext = *ext }
+
+// Extend includes in e the extensions defined in ext.
+func (e *Extension) Extend(ext *Extension) {
+	for name, fext := range ext.funcs {
+		e.DecodeFunc(name, fext.key, fext.args...)
+	}
+	for name, value := range ext.consts {
+		e.DecodeConst(name, value)
+	}
+	for key, decode := range ext.keyed {
+		e.DecodeKeyed(key, decode)
+	}
+	for typ, encode := range ext.encode {
+		if e.encode == nil {
+			e.encode = make(map[reflect.Type]func(v interface{}) ([]byte, error))
+		}
+		e.encode[typ] = encode
+	}
+}
+
+// DecodeFunc defines a function call that may be observed inside JSON content.
+// A function with the provided name will be unmarshaled as the document
+// {key: {args[0]: ..., args[N]: ...}}.
+func (e *Extension) DecodeFunc(name string, key string, args ...string) {
+	if e.funcs == nil {
+		e.funcs = make(map[string]funcExt)
+	}
+	e.funcs[name] = funcExt{key, args}
+}
+
+// DecodeConst defines a constant name that may be observed inside JSON content
+// and will be decoded with the provided value.
+func (e *Extension) DecodeConst(name string, value interface{}) {
+	if e.consts == nil {
+		e.consts = make(map[string]interface{})
+	}
+	e.consts[name] = value
+}
+
+// DecodeKeyed defines a key that when observed as the first element inside a
+// JSON document triggers the decoding of that document via the provided
+// decode function.
+func (e *Extension) DecodeKeyed(key string, decode func(data []byte) (interface{}, error)) {
+	if e.keyed == nil {
+		e.keyed = make(map[string]func([]byte) (interface{}, error))
+	}
+	e.keyed[key] = decode
+}
+
+// DecodeUnquotedKeys defines whether to accept map keys that are unquoted strings.
+func (e *Extension) DecodeUnquotedKeys(accept bool) {
+	e.unquotedKeys = accept
+}
+
+// DecodeTrailingCommas defines whether to accept trailing commas in maps and arrays.
+func (e *Extension) DecodeTrailingCommas(accept bool) {
+	e.trailingCommas = accept
+}
+
+// EncodeType registers a function to encode values with the same type of the
+// provided sample.
+func (e *Extension) EncodeType(sample interface{}, encode func(v interface{}) ([]byte, error)) {
+	if e.encode == nil {
+		e.encode = make(map[reflect.Type]func(v interface{}) ([]byte, error))
+	}
+	e.encode[reflect.TypeOf(sample)] = encode
+}

vendor/gopkg.in/mgo.v2/internal/json/fold.go

@@ -0,0 +1,143 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package json
+
+import (
+	"bytes"
+	"unicode/utf8"
+)
+
+const (
+	caseMask     = ^byte(0x20) // Mask to ignore case in ASCII.
+	kelvin       = '\u212a'
+	smallLongEss = '\u017f'
+)
+
+// foldFunc returns one of four different case folding equivalence
+// functions, from most general (and slow) to fastest:
+//
+// 1) bytes.EqualFold, if the key s contains any non-ASCII UTF-8
+// 2) equalFoldRight, if s contains special folding ASCII ('k', 'K', 's', 'S')
+// 3) asciiEqualFold, no special, but includes non-letters (including _)
+// 4) simpleLetterEqualFold, no specials, no non-letters.
+//
+// The letters S and K are special because they map to 3 runes, not just 2:
+//  * S maps to s and to U+017F 'ſ' Latin small letter long s
+//  * k maps to K and to U+212A 'K' Kelvin sign
+// See https://play.golang.org/p/tTxjOc0OGo
+//
+// The returned function is specialized for matching against s and
+// should only be given s. It's not curried for performance reasons.
+func foldFunc(s []byte) func(s, t []byte) bool {
+	nonLetter := false
+	special := false // special letter
+	for _, b := range s {
+		if b >= utf8.RuneSelf {
+			return bytes.EqualFold
+		}
+		upper := b & caseMask
+		if upper < 'A' || upper > 'Z' {
+			nonLetter = true
+		} else if upper == 'K' || upper == 'S' {
+			// See above for why these letters are special.
+			special = true
+		}
+	}
+	if special {
+		return equalFoldRight
+	}
+	if nonLetter {
+		return asciiEqualFold
+	}
+	return simpleLetterEqualFold
+}
+
+// equalFoldRight is a specialization of bytes.EqualFold when s is
+// known to be all ASCII (including punctuation), but contains an 's',
+// 'S', 'k', or 'K', requiring a Unicode fold on the bytes in t.
+// See comments on foldFunc.
+func equalFoldRight(s, t []byte) bool {
+	for _, sb := range s {
+		if len(t) == 0 {
+			return false
+		}
+		tb := t[0]
+		if tb < utf8.RuneSelf {
+			if sb != tb {
+				sbUpper := sb & caseMask
+				if 'A' <= sbUpper && sbUpper <= 'Z' {
+					if sbUpper != tb&caseMask {
+						return false
+					}
+				} else {
+					return false
+				}
+			}
+			t = t[1:]
+			continue
+		}
+		// sb is ASCII and t is not. t must be either kelvin
+		// sign or long s; sb must be s, S, k, or K.
+		tr, size := utf8.DecodeRune(t)
+		switch sb {
+		case 's', 'S':
+			if tr != smallLongEss {
+				return false
+			}
+		case 'k', 'K':
+			if tr != kelvin {
+				return false
+			}
+		default:
+			return false
+		}
+		t = t[size:]
+
+	}
+	if len(t) > 0 {
+		return false
+	}
+	return true
+}
+
+// asciiEqualFold is a specialization of bytes.EqualFold for use when
+// s is all ASCII (but may contain non-letters) and contains no
+// special-folding letters.
+// See comments on foldFunc.
+func asciiEqualFold(s, t []byte) bool {
+	if len(s) != len(t) {
+		return false
+	}
+	for i, sb := range s {
+		tb := t[i]
+		if sb == tb {
+			continue
+		}
+		if ('a' <= sb && sb <= 'z') || ('A' <= sb && sb <= 'Z') {
+			if sb&caseMask != tb&caseMask {
+				return false
+			}
+		} else {
+			return false
+		}
+	}
+	return true
+}
+
+// simpleLetterEqualFold is a specialization of bytes.EqualFold for
+// use when s is all ASCII letters (no underscores, etc) and also
+// doesn't contain 'k', 'K', 's', or 'S'.
+// See comments on foldFunc.
+func simpleLetterEqualFold(s, t []byte) bool {
+	if len(s) != len(t) {
+		return false
+	}
+	for i, b := range s {
+		if b&caseMask != t[i]&caseMask {
+			return false
+		}
+	}
+	return true
+}

vendor/gopkg.in/mgo.v2/internal/json/indent.go

@@ -0,0 +1,141 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package json
+
+import "bytes"
+
+// Compact appends to dst the JSON-encoded src with
+// insignificant space characters elided.
+func Compact(dst *bytes.Buffer, src []byte) error {
+	return compact(dst, src, false)
+}
+
+func compact(dst *bytes.Buffer, src []byte, escape bool) error {
+	origLen := dst.Len()
+	var scan scanner
+	scan.reset()
+	start := 0
+	for i, c := range src {
+		if escape && (c == '<' || c == '>' || c == '&') {
+			if start < i {
+				dst.Write(src[start:i])
+			}
+			dst.WriteString(`\u00`)
+			dst.WriteByte(hex[c>>4])
+			dst.WriteByte(hex[c&0xF])
+			start = i + 1
+		}
+		// Convert U+2028 and U+2029 (E2 80 A8 and E2 80 A9).
+		if c == 0xE2 && i+2 < len(src) && src[i+1] == 0x80 && src[i+2]&^1 == 0xA8 {
+			if start < i {
+				dst.Write(src[start:i])
+			}
+			dst.WriteString(`\u202`)
+			dst.WriteByte(hex[src[i+2]&0xF])
+			start = i + 3
+		}
+		v := scan.step(&scan, c)
+		if v >= scanSkipSpace {
+			if v == scanError {
+				break
+			}
+			if start < i {
+				dst.Write(src[start:i])
+			}
+			start = i + 1
+		}
+	}
+	if scan.eof() == scanError {
+		dst.Truncate(origLen)
+		return scan.err
+	}
+	if start < len(src) {
+		dst.Write(src[start:])
+	}
+	return nil
+}
+
+func newline(dst *bytes.Buffer, prefix, indent string, depth int) {
+	dst.WriteByte('\n')
+	dst.WriteString(prefix)
+	for i := 0; i < depth; i++ {
+		dst.WriteString(indent)
+	}
+}
+
+// Indent appends to dst an indented form of the JSON-encoded src.
+// Each element in a JSON object or array begins on a new,
+// indented line beginning with prefix followed by one or more
+// copies of indent according to the indentation nesting.
+// The data appended to dst does not begin with the prefix nor
+// any indentation, to make it easier to embed inside other formatted JSON data.
+// Although leading space characters (space, tab, carriage return, newline)
+// at the beginning of src are dropped, trailing space characters
+// at the end of src are preserved and copied to dst.
+// For example, if src has no trailing spaces, neither will dst;
+// if src ends in a trailing newline, so will dst.
+func Indent(dst *bytes.Buffer, src []byte, prefix, indent string) error {
+	origLen := dst.Len()
+	var scan scanner
+	scan.reset()
+	needIndent := false
+	depth := 0
+	for _, c := range src {
+		scan.bytes++
+		v := scan.step(&scan, c)
+		if v == scanSkipSpace {
+			continue
+		}
+		if v == scanError {
+			break
+		}
+		if needIndent && v != scanEndObject && v != scanEndArray {
+			needIndent = false
+			depth++
+			newline(dst, prefix, indent, depth)
+		}
+
+		// Emit semantically uninteresting bytes
+		// (in particular, punctuation in strings) unmodified.
+		if v == scanContinue {
+			dst.WriteByte(c)
+			continue
+		}
+
+		// Add spacing around real punctuation.
+		switch c {
+		case '{', '[':
+			// delay indent so that empty object and array are formatted as {} and [].
+			needIndent = true
+			dst.WriteByte(c)
+
+		case ',':
+			dst.WriteByte(c)
+			newline(dst, prefix, indent, depth)
+
+		case ':':
+			dst.WriteByte(c)
+			dst.WriteByte(' ')
+
+		case '}', ']':
+			if needIndent {
+				// suppress indent in empty object/array
+				needIndent = false
+			} else {
+				depth--
+				newline(dst, prefix, indent, depth)
+			}
+			dst.WriteByte(c)
+
+		default:
+			dst.WriteByte(c)
+		}
+	}
+	if scan.eof() == scanError {
+		dst.Truncate(origLen)
+		return scan.err
+	}
+	return nil
+}

vendor/gopkg.in/mgo.v2/internal/json/scanner.go

@@ -0,0 +1,697 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package json
+
+// JSON value parser state machine.
+// Just about at the limit of what is reasonable to write by hand.
+// Some parts are a bit tedious, but overall it nicely factors out the
+// otherwise common code from the multiple scanning functions
+// in this package (Compact, Indent, checkValid, nextValue, etc).
+//
+// This file starts with two simple examples using the scanner
+// before diving into the scanner itself.
+
+import "strconv"
+
+// checkValid verifies that data is valid JSON-encoded data.
+// scan is passed in for use by checkValid to avoid an allocation.
+func checkValid(data []byte, scan *scanner) error {
+	scan.reset()
+	for _, c := range data {
+		scan.bytes++
+		if scan.step(scan, c) == scanError {
+			return scan.err
+		}
+	}
+	if scan.eof() == scanError {
+		return scan.err
+	}
+	return nil
+}
+
+// nextValue splits data after the next whole JSON value,
+// returning that value and the bytes that follow it as separate slices.
+// scan is passed in for use by nextValue to avoid an allocation.
+func nextValue(data []byte, scan *scanner) (value, rest []byte, err error) {
+	scan.reset()
+	for i, c := range data {
+		v := scan.step(scan, c)
+		if v >= scanEndObject {
+			switch v {
+			// probe the scanner with a space to determine whether we will
+			// get scanEnd on the next character. Otherwise, if the next character
+			// is not a space, scanEndTop allocates a needless error.
+			case scanEndObject, scanEndArray, scanEndParams:
+				if scan.step(scan, ' ') == scanEnd {
+					return data[:i+1], data[i+1:], nil
+				}
+			case scanError:
+				return nil, nil, scan.err
+			case scanEnd:
+				return data[:i], data[i:], nil
+			}
+		}
+	}
+	if scan.eof() == scanError {
+		return nil, nil, scan.err
+	}
+	return data, nil, nil
+}
+
+// A SyntaxError is a description of a JSON syntax error.
+type SyntaxError struct {
+	msg    string // description of error
+	Offset int64  // error occurred after reading Offset bytes
+}
+
+func (e *SyntaxError) Error() string { return e.msg }
+
+// A scanner is a JSON scanning state machine.
+// Callers call scan.reset() and then pass bytes in one at a time
+// by calling scan.step(&scan, c) for each byte.
+// The return value, referred to as an opcode, tells the
+// caller about significant parsing events like beginning
+// and ending literals, objects, and arrays, so that the
+// caller can follow along if it wishes.
+// The return value scanEnd indicates that a single top-level
+// JSON value has been completed, *before* the byte that
+// just got passed in.  (The indication must be delayed in order
+// to recognize the end of numbers: is 123 a whole value or
+// the beginning of 12345e+6?).
+type scanner struct {
+	// The step is a func to be called to execute the next transition.
+	// Also tried using an integer constant and a single func
+	// with a switch, but using the func directly was 10% faster
+	// on a 64-bit Mac Mini, and it's nicer to read.
+	step func(*scanner, byte) int
+
+	// Reached end of top-level value.
+	endTop bool
+
+	// Stack of what we're in the middle of - array values, object keys, object values.
+	parseState []int
+
+	// Error that happened, if any.
+	err error
+
+	// 1-byte redo (see undo method)
+	redo      bool
+	redoCode  int
+	redoState func(*scanner, byte) int
+
+	// total bytes consumed, updated by decoder.Decode
+	bytes int64
+}
+
+// These values are returned by the state transition functions
+// assigned to scanner.state and the method scanner.eof.
+// They give details about the current state of the scan that
+// callers might be interested to know about.
+// It is okay to ignore the return value of any particular
+// call to scanner.state: if one call returns scanError,
+// every subsequent call will return scanError too.
+const (
+	// Continue.
+	scanContinue     = iota // uninteresting byte
+	scanBeginLiteral        // end implied by next result != scanContinue
+	scanBeginObject         // begin object
+	scanObjectKey           // just finished object key (string)
+	scanObjectValue         // just finished non-last object value
+	scanEndObject           // end object (implies scanObjectValue if possible)
+	scanBeginArray          // begin array
+	scanArrayValue          // just finished array value
+	scanEndArray            // end array (implies scanArrayValue if possible)
+	scanBeginName           // begin function call
+	scanParam               // begin function argument
+	scanEndParams           // end function call
+	scanSkipSpace           // space byte; can skip; known to be last "continue" result
+
+	// Stop.
+	scanEnd   // top-level value ended *before* this byte; known to be first "stop" result
+	scanError // hit an error, scanner.err.
+)
+
+// These values are stored in the parseState stack.
+// They give the current state of a composite value
+// being scanned. If the parser is inside a nested value
+// the parseState describes the nested state, outermost at entry 0.
+const (
+	parseObjectKey   = iota // parsing object key (before colon)
+	parseObjectValue        // parsing object value (after colon)
+	parseArrayValue         // parsing array value
+	parseName               // parsing unquoted name
+	parseParam              // parsing function argument value
+)
+
+// reset prepares the scanner for use.
+// It must be called before calling s.step.
+func (s *scanner) reset() {
+	s.step = stateBeginValue
+	s.parseState = s.parseState[0:0]
+	s.err = nil
+	s.redo = false
+	s.endTop = false
+}
+
+// eof tells the scanner that the end of input has been reached.
+// It returns a scan status just as s.step does.
+func (s *scanner) eof() int {
+	if s.err != nil {
+		return scanError
+	}
+	if s.endTop {
+		return scanEnd
+	}
+	s.step(s, ' ')
+	if s.endTop {
+		return scanEnd
+	}
+	if s.err == nil {
+		s.err = &SyntaxError{"unexpected end of JSON input", s.bytes}
+	}
+	return scanError
+}
+
+// pushParseState pushes a new parse state p onto the parse stack.
+func (s *scanner) pushParseState(p int) {
+	s.parseState = append(s.parseState, p)
+}
+
+// popParseState pops a parse state (already obtained) off the stack
+// and updates s.step accordingly.
+func (s *scanner) popParseState() {
+	n := len(s.parseState) - 1
+	s.parseState = s.parseState[0:n]
+	s.redo = false
+	if n == 0 {
+		s.step = stateEndTop
+		s.endTop = true
+	} else {
+		s.step = stateEndValue
+	}
+}
+
+func isSpace(c byte) bool {
+	return c == ' ' || c == '\t' || c == '\r' || c == '\n'
+}
+
+// stateBeginValueOrEmpty is the state after reading `[`.
+func stateBeginValueOrEmpty(s *scanner, c byte) int {
+	if c <= ' ' && isSpace(c) {
+		return scanSkipSpace
+	}
+	if c == ']' {
+		return stateEndValue(s, c)
+	}
+	return stateBeginValue(s, c)
+}
+
+// stateBeginValue is the state at the beginning of the input.
+func stateBeginValue(s *scanner, c byte) int {
+	if c <= ' ' && isSpace(c) {
+		return scanSkipSpace
+	}
+	switch c {
+	case '{':
+		s.step = stateBeginStringOrEmpty
+		s.pushParseState(parseObjectKey)
+		return scanBeginObject
+	case '[':
+		s.step = stateBeginValueOrEmpty
+		s.pushParseState(parseArrayValue)
+		return scanBeginArray
+	case '"':
+		s.step = stateInString
+		return scanBeginLiteral
+	case '-':
+		s.step = stateNeg
+		return scanBeginLiteral
+	case '0': // beginning of 0.123
+		s.step = state0
+		return scanBeginLiteral
+	case 'n':
+		s.step = stateNew0
+		return scanBeginName
+	}
+	if '1' <= c && c <= '9' { // beginning of 1234.5
+		s.step = state1
+		return scanBeginLiteral
+	}
+	if isName(c) {
+		s.step = stateName
+		return scanBeginName
+	}
+	return s.error(c, "looking for beginning of value")
+}
+
+func isName(c byte) bool {
+	return c == '$' || c == '_' || 'a' <= c && c <= 'z' || 'A' <= c && c <= 'Z' || '0' <= c && c <= '9'
+}
+
+// stateBeginStringOrEmpty is the state after reading `{`.
+func stateBeginStringOrEmpty(s *scanner, c byte) int {
+	if c <= ' ' && isSpace(c) {
+		return scanSkipSpace
+	}
+	if c == '}' {
+		n := len(s.parseState)
+		s.parseState[n-1] = parseObjectValue
+		return stateEndValue(s, c)
+	}
+	return stateBeginString(s, c)
+}
+
+// stateBeginString is the state after reading `{"key": value,`.
+func stateBeginString(s *scanner, c byte) int {
+	if c <= ' ' && isSpace(c) {
+		return scanSkipSpace
+	}
+	if c == '"' {
+		s.step = stateInString
+		return scanBeginLiteral
+	}
+	if isName(c) {
+		s.step = stateName
+		return scanBeginName
+	}
+	return s.error(c, "looking for beginning of object key string")
+}
+
+// stateEndValue is the state after completing a value,
+// such as after reading `{}` or `true` or `["x"`.
+func stateEndValue(s *scanner, c byte) int {
+	n := len(s.parseState)
+	if n == 0 {
+		// Completed top-level before the current byte.
+		s.step = stateEndTop
+		s.endTop = true
+		return stateEndTop(s, c)
+	}
+	if c <= ' ' && isSpace(c) {
+		s.step = stateEndValue
+		return scanSkipSpace
+	}
+	ps := s.parseState[n-1]
+	switch ps {
+	case parseObjectKey:
+		if c == ':' {
+			s.parseState[n-1] = parseObjectValue
+			s.step = stateBeginValue
+			return scanObjectKey
+		}
+		return s.error(c, "after object key")
+	case parseObjectValue:
+		if c == ',' {
+			s.parseState[n-1] = parseObjectKey
+			s.step = stateBeginStringOrEmpty
+			return scanObjectValue
+		}
+		if c == '}' {
+			s.popParseState()
+			return scanEndObject
+		}
+		return s.error(c, "after object key:value pair")
+	case parseArrayValue:
+		if c == ',' {
+			s.step = stateBeginValueOrEmpty
+			return scanArrayValue
+		}
+		if c == ']' {
+			s.popParseState()
+			return scanEndArray
+		}
+		return s.error(c, "after array element")
+	case parseParam:
+		if c == ',' {
+			s.step = stateBeginValue
+			return scanParam
+		}
+		if c == ')' {
+			s.popParseState()
+			return scanEndParams
+		}
+		return s.error(c, "after array element")
+	}
+	return s.error(c, "")
+}
+
+// stateEndTop is the state after finishing the top-level value,
+// such as after reading `{}` or `[1,2,3]`.
+// Only space characters should be seen now.
+func stateEndTop(s *scanner, c byte) int {
+	if c != ' ' && c != '\t' && c != '\r' && c != '\n' {
+		// Complain about non-space byte on next call.
+		s.error(c, "after top-level value")
+	}
+	return scanEnd
+}
+
+// stateInString is the state after reading `"`.
+func stateInString(s *scanner, c byte) int {
+	if c == '"' {
+		s.step = stateEndValue
+		return scanContinue
+	}
+	if c == '\\' {
+		s.step = stateInStringEsc
+		return scanContinue
+	}
+	if c < 0x20 {
+		return s.error(c, "in string literal")
+	}
+	return scanContinue
+}
+
+// stateInStringEsc is the state after reading `"\` during a quoted string.
+func stateInStringEsc(s *scanner, c byte) int {
+	switch c {
+	case 'b', 'f', 'n', 'r', 't', '\\', '/', '"':
+		s.step = stateInString
+		return scanContinue
+	case 'u':
+		s.step = stateInStringEscU
+		return scanContinue
+	}
+	return s.error(c, "in string escape code")
+}
+
+// stateInStringEscU is the state after reading `"\u` during a quoted string.
+func stateInStringEscU(s *scanner, c byte) int {
+	if '0' <= c && c <= '9' || 'a' <= c && c <= 'f' || 'A' <= c && c <= 'F' {
+		s.step = stateInStringEscU1
+		return scanContinue
+	}
+	// numbers
+	return s.error(c, "in \\u hexadecimal character escape")
+}
+
+// stateInStringEscU1 is the state after reading `"\u1` during a quoted string.
+func stateInStringEscU1(s *scanner, c byte) int {
+	if '0' <= c && c <= '9' || 'a' <= c && c <= 'f' || 'A' <= c && c <= 'F' {
+		s.step = stateInStringEscU12
+		return scanContinue
+	}
+	// numbers
+	return s.error(c, "in \\u hexadecimal character escape")
+}
+
+// stateInStringEscU12 is the state after reading `"\u12` during a quoted string.
+func stateInStringEscU12(s *scanner, c byte) int {
+	if '0' <= c && c <= '9' || 'a' <= c && c <= 'f' || 'A' <= c && c <= 'F' {
+		s.step = stateInStringEscU123
+		return scanContinue
+	}
+	// numbers
+	return s.error(c, "in \\u hexadecimal character escape")
+}
+
+// stateInStringEscU123 is the state after reading `"\u123` during a quoted string.
+func stateInStringEscU123(s *scanner, c byte) int {
+	if '0' <= c && c <= '9' || 'a' <= c && c <= 'f' || 'A' <= c && c <= 'F' {
+		s.step = stateInString
+		return scanContinue
+	}
+	// numbers
+	return s.error(c, "in \\u hexadecimal character escape")
+}
+
+// stateNeg is the state after reading `-` during a number.
+func stateNeg(s *scanner, c byte) int {
+	if c == '0' {
+		s.step = state0
+		return scanContinue
+	}
+	if '1' <= c && c <= '9' {
+		s.step = state1
+		return scanContinue
+	}
+	return s.error(c, "in numeric literal")
+}
+
+// state1 is the state after reading a non-zero integer during a number,
+// such as after reading `1` or `100` but not `0`.
+func state1(s *scanner, c byte) int {
+	if '0' <= c && c <= '9' {
+		s.step = state1
+		return scanContinue
+	}
+	return state0(s, c)
+}
+
+// state0 is the state after reading `0` during a number.
+func state0(s *scanner, c byte) int {
+	if c == '.' {
+		s.step = stateDot
+		return scanContinue
+	}
+	if c == 'e' || c == 'E' {
+		s.step = stateE
+		return scanContinue
+	}
+	return stateEndValue(s, c)
+}
+
+// stateDot is the state after reading the integer and decimal point in a number,
+// such as after reading `1.`.
+func stateDot(s *scanner, c byte) int {
+	if '0' <= c && c <= '9' {
+		s.step = stateDot0
+		return scanContinue
+	}
+	return s.error(c, "after decimal point in numeric literal")
+}
+
+// stateDot0 is the state after reading the integer, decimal point, and subsequent
+// digits of a number, such as after reading `3.14`.
+func stateDot0(s *scanner, c byte) int {
+	if '0' <= c && c <= '9' {
+		return scanContinue
+	}
+	if c == 'e' || c == 'E' {
+		s.step = stateE
+		return scanContinue
+	}
+	return stateEndValue(s, c)
+}
+
+// stateE is the state after reading the mantissa and e in a number,
+// such as after reading `314e` or `0.314e`.
+func stateE(s *scanner, c byte) int {
+	if c == '+' || c == '-' {
+		s.step = stateESign
+		return scanContinue
+	}
+	return stateESign(s, c)
+}
+
+// stateESign is the state after reading the mantissa, e, and sign in a number,
+// such as after reading `314e-` or `0.314e+`.
+func stateESign(s *scanner, c byte) int {
+	if '0' <= c && c <= '9' {
+		s.step = stateE0
+		return scanContinue
+	}
+	return s.error(c, "in exponent of numeric literal")
+}
+
+// stateE0 is the state after reading the mantissa, e, optional sign,
+// and at least one digit of the exponent in a number,
+// such as after reading `314e-2` or `0.314e+1` or `3.14e0`.
+func stateE0(s *scanner, c byte) int {
+	if '0' <= c && c <= '9' {
+		return scanContinue
+	}
+	return stateEndValue(s, c)
+}
+
+// stateNew0 is the state after reading `n`.
+func stateNew0(s *scanner, c byte) int {
+	if c == 'e' {
+		s.step = stateNew1
+		return scanContinue
+	}
+	s.step = stateName
+	return stateName(s, c)
+}
+
+// stateNew1 is the state after reading `ne`.
+func stateNew1(s *scanner, c byte) int {
+	if c == 'w' {
+		s.step = stateNew2
+		return scanContinue
+	}
+	s.step = stateName
+	return stateName(s, c)
+}
+
+// stateNew2 is the state after reading `new`.
+func stateNew2(s *scanner, c byte) int {
+	s.step = stateName
+	if c == ' ' {
+		return scanContinue
+	}
+	return stateName(s, c)
+}
+
+// stateName is the state while reading an unquoted function name.
+func stateName(s *scanner, c byte) int {
+	if isName(c) {
+		return scanContinue
+	}
+	if c == '(' {
+		s.step = stateParamOrEmpty
+		s.pushParseState(parseParam)
+		return scanParam
+	}
+	return stateEndValue(s, c)
+}
+
+// stateParamOrEmpty is the state after reading `(`.
+func stateParamOrEmpty(s *scanner, c byte) int {
+	if c <= ' ' && isSpace(c) {
+		return scanSkipSpace
+	}
+	if c == ')' {
+		return stateEndValue(s, c)
+	}
+	return stateBeginValue(s, c)
+}
+
+// stateT is the state after reading `t`.
+func stateT(s *scanner, c byte) int {
+	if c == 'r' {
+		s.step = stateTr
+		return scanContinue
+	}
+	return s.error(c, "in literal true (expecting 'r')")
+}
+
+// stateTr is the state after reading `tr`.
+func stateTr(s *scanner, c byte) int {
+	if c == 'u' {
+		s.step = stateTru
+		return scanContinue
+	}
+	return s.error(c, "in literal true (expecting 'u')")
+}
+
+// stateTru is the state after reading `tru`.
+func stateTru(s *scanner, c byte) int {
+	if c == 'e' {
+		s.step = stateEndValue
+		return scanContinue
+	}
+	return s.error(c, "in literal true (expecting 'e')")
+}
+
+// stateF is the state after reading `f`.
+func stateF(s *scanner, c byte) int {
+	if c == 'a' {
+		s.step = stateFa
+		return scanContinue
+	}
+	return s.error(c, "in literal false (expecting 'a')")
+}
+
+// stateFa is the state after reading `fa`.
+func stateFa(s *scanner, c byte) int {
+	if c == 'l' {
+		s.step = stateFal
+		return scanContinue
+	}
+	return s.error(c, "in literal false (expecting 'l')")
+}
+
+// stateFal is the state after reading `fal`.
+func stateFal(s *scanner, c byte) int {
+	if c == 's' {
+		s.step = stateFals
+		return scanContinue
+	}
+	return s.error(c, "in literal false (expecting 's')")
+}
+
+// stateFals is the state after reading `fals`.
+func stateFals(s *scanner, c byte) int {
+	if c == 'e' {
+		s.step = stateEndValue
+		return scanContinue
+	}
+	return s.error(c, "in literal false (expecting 'e')")
+}
+
+// stateN is the state after reading `n`.
+func stateN(s *scanner, c byte) int {
+	if c == 'u' {
+		s.step = stateNu
+		return scanContinue
+	}
+	return s.error(c, "in literal null (expecting 'u')")
+}
+
+// stateNu is the state after reading `nu`.
+func stateNu(s *scanner, c byte) int {
+	if c == 'l' {
+		s.step = stateNul
+		return scanContinue
+	}
+	return s.error(c, "in literal null (expecting 'l')")
+}
+
+// stateNul is the state after reading `nul`.
+func stateNul(s *scanner, c byte) int {
+	if c == 'l' {
+		s.step = stateEndValue
+		return scanContinue
+	}
+	return s.error(c, "in literal null (expecting 'l')")
+}
+
+// stateError is the state after reaching a syntax error,
+// such as after reading `[1}` or `5.1.2`.
+func stateError(s *scanner, c byte) int {
+	return scanError
+}
+
+// error records an error and switches to the error state.
+func (s *scanner) error(c byte, context string) int {
+	s.step = stateError
+	s.err = &SyntaxError{"invalid character " + quoteChar(c) + " " + context, s.bytes}
+	return scanError
+}
+
+// quoteChar formats c as a quoted character literal
+func quoteChar(c byte) string {
+	// special cases - different from quoted strings
+	if c == '\'' {
+		return `'\''`
+	}
+	if c == '"' {
+		return `'"'`
+	}
+
+	// use quoted string with different quotation marks
+	s := strconv.Quote(string(c))
+	return "'" + s[1:len(s)-1] + "'"
+}
+
+// undo causes the scanner to return scanCode from the next state transition.
+// This gives callers a simple 1-byte undo mechanism.
+func (s *scanner) undo(scanCode int) {
+	if s.redo {
+		panic("json: invalid use of scanner")
+	}
+	s.redoCode = scanCode
+	s.redoState = s.step
+	s.step = stateRedo
+	s.redo = true
+}
+
+// stateRedo helps implement the scanner's 1-byte undo.
+func stateRedo(s *scanner, c byte) int {
+	s.redo = false
+	s.step = s.redoState
+	return s.redoCode
+}

vendor/gopkg.in/mgo.v2/internal/json/stream.go

@@ -0,0 +1,510 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package json
+
+import (
+	"bytes"
+	"errors"
+	"io"
+)
+
+// A Decoder reads and decodes JSON values from an input stream.
+type Decoder struct {
+	r     io.Reader
+	buf   []byte
+	d     decodeState
+	scanp int // start of unread data in buf
+	scan  scanner
+	err   error
+
+	tokenState int
+	tokenStack []int
+}
+
+// NewDecoder returns a new decoder that reads from r.
+//
+// The decoder introduces its own buffering and may
+// read data from r beyond the JSON values requested.
+func NewDecoder(r io.Reader) *Decoder {
+	return &Decoder{r: r}
+}
+
+// UseNumber causes the Decoder to unmarshal a number into an interface{} as a
+// Number instead of as a float64.
+func (dec *Decoder) UseNumber() { dec.d.useNumber = true }
+
+// Decode reads the next JSON-encoded value from its
+// input and stores it in the value pointed to by v.
+//
+// See the documentation for Unmarshal for details about
+// the conversion of JSON into a Go value.
+func (dec *Decoder) Decode(v interface{}) error {
+	if dec.err != nil {
+		return dec.err
+	}
+
+	if err := dec.tokenPrepareForDecode(); err != nil {
+		return err
+	}
+
+	if !dec.tokenValueAllowed() {
+		return &SyntaxError{msg: "not at beginning of value"}
+	}
+
+	// Read whole value into buffer.
+	n, err := dec.readValue()
+	if err != nil {
+		return err
+	}
+	dec.d.init(dec.buf[dec.scanp : dec.scanp+n])
+	dec.scanp += n
+
+	// Don't save err from unmarshal into dec.err:
+	// the connection is still usable since we read a complete JSON
+	// object from it before the error happened.
+	err = dec.d.unmarshal(v)
+
+	// fixup token streaming state
+	dec.tokenValueEnd()
+
+	return err
+}
+
+// Buffered returns a reader of the data remaining in the Decoder's
+// buffer. The reader is valid until the next call to Decode.
+func (dec *Decoder) Buffered() io.Reader {
+	return bytes.NewReader(dec.buf[dec.scanp:])
+}
+
+// readValue reads a JSON value into dec.buf.
+// It returns the length of the encoding.
+func (dec *Decoder) readValue() (int, error) {
+	dec.scan.reset()
+
+	scanp := dec.scanp
+	var err error
+Input:
+	for {
+		// Look in the buffer for a new value.
+		for i, c := range dec.buf[scanp:] {
+			dec.scan.bytes++
+			v := dec.scan.step(&dec.scan, c)
+			if v == scanEnd {
+				scanp += i
+				break Input
+			}
+			// scanEnd is delayed one byte.
+			// We might block trying to get that byte from src,
+			// so instead invent a space byte.
+			if (v == scanEndObject || v == scanEndArray) && dec.scan.step(&dec.scan, ' ') == scanEnd {
+				scanp += i + 1
+				break Input
+			}
+			if v == scanError {
+				dec.err = dec.scan.err
+				return 0, dec.scan.err
+			}
+		}
+		scanp = len(dec.buf)
+
+		// Did the last read have an error?
+		// Delayed until now to allow buffer scan.
+		if err != nil {
+			if err == io.EOF {
+				if dec.scan.step(&dec.scan, ' ') == scanEnd {
+					break Input
+				}
+				if nonSpace(dec.buf) {
+					err = io.ErrUnexpectedEOF
+				}
+			}
+			dec.err = err
+			return 0, err
+		}
+
+		n := scanp - dec.scanp
+		err = dec.refill()
+		scanp = dec.scanp + n
+	}
+	return scanp - dec.scanp, nil
+}
+
+func (dec *Decoder) refill() error {
+	// Make room to read more into the buffer.
+	// First slide down data already consumed.
+	if dec.scanp > 0 {
+		n := copy(dec.buf, dec.buf[dec.scanp:])
+		dec.buf = dec.buf[:n]
+		dec.scanp = 0
+	}
+
+	// Grow buffer if not large enough.
+	const minRead = 512
+	if cap(dec.buf)-len(dec.buf) < minRead {
+		newBuf := make([]byte, len(dec.buf), 2*cap(dec.buf)+minRead)
+		copy(newBuf, dec.buf)
+		dec.buf = newBuf
+	}
+
+	// Read. Delay error for next iteration (after scan).
+	n, err := dec.r.Read(dec.buf[len(dec.buf):cap(dec.buf)])
+	dec.buf = dec.buf[0 : len(dec.buf)+n]
+
+	return err
+}
+
+func nonSpace(b []byte) bool {
+	for _, c := range b {
+		if !isSpace(c) {
+			return true
+		}
+	}
+	return false
+}
+
+// An Encoder writes JSON values to an output stream.
+type Encoder struct {
+	w          io.Writer
+	err        error
+	escapeHTML bool
+
+	indentBuf    *bytes.Buffer
+	indentPrefix string
+	indentValue  string
+
+	ext Extension
+}
+
+// NewEncoder returns a new encoder that writes to w.
+func NewEncoder(w io.Writer) *Encoder {
+	return &Encoder{w: w, escapeHTML: true}
+}
+
+// Encode writes the JSON encoding of v to the stream,
+// followed by a newline character.
+//
+// See the documentation for Marshal for details about the
+// conversion of Go values to JSON.
+func (enc *Encoder) Encode(v interface{}) error {
+	if enc.err != nil {
+		return enc.err
+	}
+	e := newEncodeState()
+	e.ext = enc.ext
+	err := e.marshal(v, encOpts{escapeHTML: enc.escapeHTML})
+	if err != nil {
+		return err
+	}
+
+	// Terminate each value with a newline.
+	// This makes the output look a little nicer
+	// when debugging, and some kind of space
+	// is required if the encoded value was a number,
+	// so that the reader knows there aren't more
+	// digits coming.
+	e.WriteByte('\n')
+
+	b := e.Bytes()
+	if enc.indentBuf != nil {
+		enc.indentBuf.Reset()
+		err = Indent(enc.indentBuf, b, enc.indentPrefix, enc.indentValue)
+		if err != nil {
+			return err
+		}
+		b = enc.indentBuf.Bytes()
+	}
+	if _, err = enc.w.Write(b); err != nil {
+		enc.err = err
+	}
+	encodeStatePool.Put(e)
+	return err
+}
+
+// Indent sets the encoder to format each encoded value with Indent.
+func (enc *Encoder) Indent(prefix, indent string) {
+	enc.indentBuf = new(bytes.Buffer)
+	enc.indentPrefix = prefix
+	enc.indentValue = indent
+}
+
+// DisableHTMLEscaping causes the encoder not to escape angle brackets
+// ("<" and ">") or ampersands ("&") in JSON strings.
+func (enc *Encoder) DisableHTMLEscaping() {
+	enc.escapeHTML = false
+}
+
+// RawMessage is a raw encoded JSON value.
+// It implements Marshaler and Unmarshaler and can
+// be used to delay JSON decoding or precompute a JSON encoding.
+type RawMessage []byte
+
+// MarshalJSON returns *m as the JSON encoding of m.
+func (m *RawMessage) MarshalJSON() ([]byte, error) {
+	return *m, nil
+}
+
+// UnmarshalJSON sets *m to a copy of data.
+func (m *RawMessage) UnmarshalJSON(data []byte) error {
+	if m == nil {
+		return errors.New("json.RawMessage: UnmarshalJSON on nil pointer")
+	}
+	*m = append((*m)[0:0], data...)
+	return nil
+}
+
+var _ Marshaler = (*RawMessage)(nil)
+var _ Unmarshaler = (*RawMessage)(nil)
+
+// A Token holds a value of one of these types:
+//
+//	Delim, for the four JSON delimiters [ ] { }
+//	bool, for JSON booleans
+//	float64, for JSON numbers
+//	Number, for JSON numbers
+//	string, for JSON string literals
+//	nil, for JSON null
+//
+type Token interface{}
+
+const (
+	tokenTopValue = iota
+	tokenArrayStart
+	tokenArrayValue
+	tokenArrayComma
+	tokenObjectStart
+	tokenObjectKey
+	tokenObjectColon
+	tokenObjectValue
+	tokenObjectComma
+)
+
+// advance tokenstate from a separator state to a value state
+func (dec *Decoder) tokenPrepareForDecode() error {
+	// Note: Not calling peek before switch, to avoid
+	// putting peek into the standard Decode path.
+	// peek is only called when using the Token API.
+	switch dec.tokenState {
+	case tokenArrayComma:
+		c, err := dec.peek()
+		if err != nil {
+			return err
+		}
+		if c != ',' {
+			return &SyntaxError{"expected comma after array element", 0}
+		}
+		dec.scanp++
+		dec.tokenState = tokenArrayValue
+	case tokenObjectColon:
+		c, err := dec.peek()
+		if err != nil {
+			return err
+		}
+		if c != ':' {
+			return &SyntaxError{"expected colon after object key", 0}
+		}
+		dec.scanp++
+		dec.tokenState = tokenObjectValue
+	}
+	return nil
+}
+
+func (dec *Decoder) tokenValueAllowed() bool {
+	switch dec.tokenState {
+	case tokenTopValue, tokenArrayStart, tokenArrayValue, tokenObjectValue:
+		return true
+	}
+	return false
+}
+
+func (dec *Decoder) tokenValueEnd() {
+	switch dec.tokenState {
+	case tokenArrayStart, tokenArrayValue:
+		dec.tokenState = tokenArrayComma
+	case tokenObjectValue:
+		dec.tokenState = tokenObjectComma
+	}
+}
+
+// A Delim is a JSON array or object delimiter, one of [ ] { or }.
+type Delim rune
+
+func (d Delim) String() string {
+	return string(d)
+}
+
+// Token returns the next JSON token in the input stream.
+// At the end of the input stream, Token returns nil, io.EOF.
+//
+// Token guarantees that the delimiters [ ] { } it returns are
+// properly nested and matched: if Token encounters an unexpected
+// delimiter in the input, it will return an error.
+//
+// The input stream consists of basic JSON values—bool, string,
+// number, and null—along with delimiters [ ] { } of type Delim
+// to mark the start and end of arrays and objects.
+// Commas and colons are elided.
+func (dec *Decoder) Token() (Token, error) {
+	for {
+		c, err := dec.peek()
+		if err != nil {
+			return nil, err
+		}
+		switch c {
+		case '[':
+			if !dec.tokenValueAllowed() {
+				return dec.tokenError(c)
+			}
+			dec.scanp++
+			dec.tokenStack = append(dec.tokenStack, dec.tokenState)
+			dec.tokenState = tokenArrayStart
+			return Delim('['), nil
+
+		case ']':
+			if dec.tokenState != tokenArrayStart && dec.tokenState != tokenArrayComma {
+				return dec.tokenError(c)
+			}
+			dec.scanp++
+			dec.tokenState = dec.tokenStack[len(dec.tokenStack)-1]
+			dec.tokenStack = dec.tokenStack[:len(dec.tokenStack)-1]
+			dec.tokenValueEnd()
+			return Delim(']'), nil
+
+		case '{':
+			if !dec.tokenValueAllowed() {
+				return dec.tokenError(c)
+			}
+			dec.scanp++
+			dec.tokenStack = append(dec.tokenStack, dec.tokenState)
+			dec.tokenState = tokenObjectStart
+			return Delim('{'), nil
+
+		case '}':
+			if dec.tokenState != tokenObjectStart && dec.tokenState != tokenObjectComma {
+				return dec.tokenError(c)
+			}
+			dec.scanp++
+			dec.tokenState = dec.tokenStack[len(dec.tokenStack)-1]
+			dec.tokenStack = dec.tokenStack[:len(dec.tokenStack)-1]
+			dec.tokenValueEnd()
+			return Delim('}'), nil
+
+		case ':':
+			if dec.tokenState != tokenObjectColon {
+				return dec.tokenError(c)
+			}
+			dec.scanp++
+			dec.tokenState = tokenObjectValue
+			continue
+
+		case ',':
+			if dec.tokenState == tokenArrayComma {
+				dec.scanp++
+				dec.tokenState = tokenArrayValue
+				continue
+			}
+			if dec.tokenState == tokenObjectComma {
+				dec.scanp++
+				dec.tokenState = tokenObjectKey
+				continue
+			}
+			return dec.tokenError(c)
+
+		case '"':
+			if dec.tokenState == tokenObjectStart || dec.tokenState == tokenObjectKey {
+				var x string
+				old := dec.tokenState
+				dec.tokenState = tokenTopValue
+				err := dec.Decode(&x)
+				dec.tokenState = old
+				if err != nil {
+					clearOffset(err)
+					return nil, err
+				}
+				dec.tokenState = tokenObjectColon
+				return x, nil
+			}
+			fallthrough
+
+		default:
+			if !dec.tokenValueAllowed() {
+				return dec.tokenError(c)
+			}
+			var x interface{}
+			if err := dec.Decode(&x); err != nil {
+				clearOffset(err)
+				return nil, err
+			}
+			return x, nil
+		}
+	}
+}
+
+func clearOffset(err error) {
+	if s, ok := err.(*SyntaxError); ok {
+		s.Offset = 0
+	}
+}
+
+func (dec *Decoder) tokenError(c byte) (Token, error) {
+	var context string
+	switch dec.tokenState {
+	case tokenTopValue:
+		context = " looking for beginning of value"
+	case tokenArrayStart, tokenArrayValue, tokenObjectValue:
+		context = " looking for beginning of value"
+	case tokenArrayComma:
+		context = " after array element"
+	case tokenObjectKey:
+		context = " looking for beginning of object key string"
+	case tokenObjectColon:
+		context = " after object key"
+	case tokenObjectComma:
+		context = " after object key:value pair"
+	}
+	return nil, &SyntaxError{"invalid character " + quoteChar(c) + " " + context, 0}
+}
+
+// More reports whether there is another element in the
+// current array or object being parsed.
+func (dec *Decoder) More() bool {
+	c, err := dec.peek()
+	return err == nil && c != ']' && c != '}'
+}
+
+func (dec *Decoder) peek() (byte, error) {
+	var err error
+	for {
+		for i := dec.scanp; i < len(dec.buf); i++ {
+			c := dec.buf[i]
+			if isSpace(c) {
+				continue
+			}
+			dec.scanp = i
+			return c, nil
+		}
+		// buffer has been scanned, now report any error
+		if err != nil {
+			return 0, err
+		}
+		err = dec.refill()
+	}
+}
+
+/*
+TODO
+
+// EncodeToken writes the given JSON token to the stream.
+// It returns an error if the delimiters [ ] { } are not properly used.
+//
+// EncodeToken does not call Flush, because usually it is part of
+// a larger operation such as Encode, and those will call Flush when finished.
+// Callers that create an Encoder and then invoke EncodeToken directly,
+// without using Encode, need to call Flush when finished to ensure that
+// the JSON is written to the underlying writer.
+func (e *Encoder) EncodeToken(t Token) error  {
+	...
+}
+
+*/

vendor/gopkg.in/mgo.v2/internal/json/tags.go

@@ -0,0 +1,44 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package json
+
+import (
+	"strings"
+)
+
+// tagOptions is the string following a comma in a struct field's "json"
+// tag, or the empty string. It does not include the leading comma.
+type tagOptions string
+
+// parseTag splits a struct field's json tag into its name and
+// comma-separated options.
+func parseTag(tag string) (string, tagOptions) {
+	if idx := strings.Index(tag, ","); idx != -1 {
+		return tag[:idx], tagOptions(tag[idx+1:])
+	}
+	return tag, tagOptions("")
+}
+
+// Contains reports whether a comma-separated list of options
+// contains a particular substr flag. substr must be surrounded by a
+// string boundary or commas.
+func (o tagOptions) Contains(optionName string) bool {
+	if len(o) == 0 {
+		return false
+	}
+	s := string(o)
+	for s != "" {
+		var next string
+		i := strings.Index(s, ",")
+		if i >= 0 {
+			s, next = s[:i], s[i+1:]
+		}
+		if s == optionName {
+			return true
+		}
+		s = next
+	}
+	return false
+}

vendor/gopkg.in/mgo.v2/internal/sasl/sasl.c

@@ -0,0 +1,77 @@
+// +build !windows
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <sasl/sasl.h>
+
+static int mgo_sasl_simple(void *context, int id, const char **result, unsigned int *len)
+{
+	if (!result) {
+		return SASL_BADPARAM;
+	}
+	switch (id) {
+	case SASL_CB_USER:
+		*result = (char *)context;
+		break;
+	case SASL_CB_AUTHNAME:
+		*result = (char *)context;
+		break;
+	case SASL_CB_LANGUAGE:
+		*result = NULL;
+		break;
+	default:
+		return SASL_BADPARAM;
+	}
+	if (len) {
+		*len = *result ? strlen(*result) : 0;
+	}
+	return SASL_OK;
+}
+
+typedef int (*callback)(void);
+
+static int mgo_sasl_secret(sasl_conn_t *conn, void *context, int id, sasl_secret_t **result)
+{
+	if (!conn || !result || id != SASL_CB_PASS) {
+		return SASL_BADPARAM;
+	}
+	*result = (sasl_secret_t *)context;
+	return SASL_OK;
+}
+
+sasl_callback_t *mgo_sasl_callbacks(const char *username, const char *password)
+{
+	sasl_callback_t *cb = malloc(4 * sizeof(sasl_callback_t));
+	int n = 0;
+
+	size_t len = strlen(password);
+	sasl_secret_t *secret = (sasl_secret_t*)malloc(sizeof(sasl_secret_t) + len);
+	if (!secret) {
+		free(cb);
+		return NULL;
+	}
+	strcpy((char *)secret->data, password);
+	secret->len = len;
+
+	cb[n].id = SASL_CB_PASS;
+	cb[n].proc = (callback)&mgo_sasl_secret;
+	cb[n].context = secret;
+	n++;
+
+	cb[n].id = SASL_CB_USER;
+	cb[n].proc = (callback)&mgo_sasl_simple;
+	cb[n].context = (char*)username;
+	n++;
+
+	cb[n].id = SASL_CB_AUTHNAME;
+	cb[n].proc = (callback)&mgo_sasl_simple;
+	cb[n].context = (char*)username;
+	n++;
+
+	cb[n].id = SASL_CB_LIST_END;
+	cb[n].proc = NULL;
+	cb[n].context = NULL;
+
+	return cb;
+}

vendor/gopkg.in/mgo.v2/internal/sasl/sasl.go

@@ -0,0 +1,138 @@
+// Package sasl is an implementation detail of the mgo package.
+//
+// This package is not meant to be used by itself.
+//
+
+// +build !windows
+
+package sasl
+
+// #cgo LDFLAGS: -lsasl2
+//
+// struct sasl_conn {};
+//
+// #include <stdlib.h>
+// #include <sasl/sasl.h>
+//
+// sasl_callback_t *mgo_sasl_callbacks(const char *username, const char *password);
+//
+import "C"
+
+import (
+	"fmt"
+	"strings"
+	"sync"
+	"unsafe"
+)
+
+type saslStepper interface {
+	Step(serverData []byte) (clientData []byte, done bool, err error)
+	Close()
+}
+
+type saslSession struct {
+	conn *C.sasl_conn_t
+	step int
+	mech string
+
+	cstrings  []*C.char
+	callbacks *C.sasl_callback_t
+}
+
+var initError error
+var initOnce sync.Once
+
+func initSASL() {
+	rc := C.sasl_client_init(nil)
+	if rc != C.SASL_OK {
+		initError = saslError(rc, nil, "cannot initialize SASL library")
+	}
+}
+
+func New(username, password, mechanism, service, host string) (saslStepper, error) {
+	initOnce.Do(initSASL)
+	if initError != nil {
+		return nil, initError
+	}
+
+	ss := &saslSession{mech: mechanism}
+	if service == "" {
+		service = "mongodb"
+	}
+	if i := strings.Index(host, ":"); i >= 0 {
+		host = host[:i]
+	}
+	ss.callbacks = C.mgo_sasl_callbacks(ss.cstr(username), ss.cstr(password))
+	rc := C.sasl_client_new(ss.cstr(service), ss.cstr(host), nil, nil, ss.callbacks, 0, &ss.conn)
+	if rc != C.SASL_OK {
+		ss.Close()
+		return nil, saslError(rc, nil, "cannot create new SASL client")
+	}
+	return ss, nil
+}
+
+func (ss *saslSession) cstr(s string) *C.char {
+	cstr := C.CString(s)
+	ss.cstrings = append(ss.cstrings, cstr)
+	return cstr
+}
+
+func (ss *saslSession) Close() {
+	for _, cstr := range ss.cstrings {
+		C.free(unsafe.Pointer(cstr))
+	}
+	ss.cstrings = nil
+
+	if ss.callbacks != nil {
+		C.free(unsafe.Pointer(ss.callbacks))
+	}
+
+	// The documentation of SASL dispose makes it clear that this should only
+	// be done when the connection is done, not when the authentication phase
+	// is done, because an encryption layer may have been negotiated.
+	// Even then, we'll do this for now, because it's simpler and prevents
+	// keeping track of this state for every socket. If it breaks, we'll fix it.
+	C.sasl_dispose(&ss.conn)
+}
+
+func (ss *saslSession) Step(serverData []byte) (clientData []byte, done bool, err error) {
+	ss.step++
+	if ss.step > 10 {
+		return nil, false, fmt.Errorf("too many SASL steps without authentication")
+	}
+	var cclientData *C.char
+	var cclientDataLen C.uint
+	var rc C.int
+	if ss.step == 1 {
+		var mechanism *C.char // ignored - must match cred
+		rc = C.sasl_client_start(ss.conn, ss.cstr(ss.mech), nil, &cclientData, &cclientDataLen, &mechanism)
+	} else {
+		var cserverData *C.char
+		var cserverDataLen C.uint
+		if len(serverData) > 0 {
+			cserverData = (*C.char)(unsafe.Pointer(&serverData[0]))
+			cserverDataLen = C.uint(len(serverData))
+		}
+		rc = C.sasl_client_step(ss.conn, cserverData, cserverDataLen, nil, &cclientData, &cclientDataLen)
+	}
+	if cclientData != nil && cclientDataLen > 0 {
+		clientData = C.GoBytes(unsafe.Pointer(cclientData), C.int(cclientDataLen))
+	}
+	if rc == C.SASL_OK {
+		return clientData, true, nil
+	}
+	if rc == C.SASL_CONTINUE {
+		return clientData, false, nil
+	}
+	return nil, false, saslError(rc, ss.conn, "cannot establish SASL session")
+}
+
+func saslError(rc C.int, conn *C.sasl_conn_t, msg string) error {
+	var detail string
+	if conn == nil {
+		detail = C.GoString(C.sasl_errstring(rc, nil, nil))
+	} else {
+		detail = C.GoString(C.sasl_errdetail(conn))
+	}
+	return fmt.Errorf(msg + ": " + detail)
+}

vendor/gopkg.in/mgo.v2/internal/sasl/sasl_windows.c

@@ -0,0 +1,122 @@
+#include "sasl_windows.h"
+
+static const LPSTR SSPI_PACKAGE_NAME = "kerberos";
+
+SECURITY_STATUS SEC_ENTRY sspi_acquire_credentials_handle(CredHandle *cred_handle, char *username, char *password, char *domain)
+{
+	SEC_WINNT_AUTH_IDENTITY auth_identity;
+	SECURITY_INTEGER ignored;
+
+	auth_identity.Flags = SEC_WINNT_AUTH_IDENTITY_ANSI;
+	auth_identity.User = (LPSTR) username;
+	auth_identity.UserLength = strlen(username);
+	auth_identity.Password = NULL;
+	auth_identity.PasswordLength = 0;
+	if(password){
+		auth_identity.Password = (LPSTR) password;
+		auth_identity.PasswordLength = strlen(password);
+	}
+	auth_identity.Domain = (LPSTR) domain;
+	auth_identity.DomainLength = strlen(domain);
+	return call_sspi_acquire_credentials_handle(NULL, SSPI_PACKAGE_NAME, SECPKG_CRED_OUTBOUND, NULL, &auth_identity, NULL, NULL, cred_handle, &ignored);
+}
+
+int sspi_step(CredHandle *cred_handle, int has_context, CtxtHandle *context, PVOID buffer, ULONG buffer_length, PVOID *out_buffer, ULONG *out_buffer_length,  char *target)
+{
+	SecBufferDesc inbuf;
+	SecBuffer in_bufs[1];
+	SecBufferDesc outbuf;
+	SecBuffer out_bufs[1];
+
+	if (has_context > 0) {
+		// If we already have a context, we now have data to send.
+		// Put this data in an inbuf.
+		inbuf.ulVersion = SECBUFFER_VERSION;
+		inbuf.cBuffers = 1;
+		inbuf.pBuffers = in_bufs;
+		in_bufs[0].pvBuffer = buffer;
+		in_bufs[0].cbBuffer = buffer_length;
+		in_bufs[0].BufferType = SECBUFFER_TOKEN;
+	}
+
+	outbuf.ulVersion = SECBUFFER_VERSION;
+	outbuf.cBuffers = 1;
+	outbuf.pBuffers = out_bufs;
+	out_bufs[0].pvBuffer = NULL;
+	out_bufs[0].cbBuffer = 0;
+	out_bufs[0].BufferType = SECBUFFER_TOKEN;
+
+	ULONG context_attr = 0;
+
+	int ret = call_sspi_initialize_security_context(cred_handle,
+	          has_context > 0 ? context : NULL,
+	          (LPSTR) target,
+	          ISC_REQ_ALLOCATE_MEMORY | ISC_REQ_MUTUAL_AUTH,
+	          0,
+	          SECURITY_NETWORK_DREP,
+	          has_context > 0 ? &inbuf : NULL,
+	          0,
+	          context,
+	          &outbuf,
+	          &context_attr,
+	          NULL);
+
+	*out_buffer = malloc(out_bufs[0].cbBuffer);
+	*out_buffer_length = out_bufs[0].cbBuffer;
+	memcpy(*out_buffer, out_bufs[0].pvBuffer, *out_buffer_length);
+
+	return ret;
+}
+
+int sspi_send_client_authz_id(CtxtHandle *context, PVOID *buffer, ULONG *buffer_length, char *user_plus_realm)
+{
+	SecPkgContext_Sizes sizes;
+	SECURITY_STATUS status = call_sspi_query_context_attributes(context, SECPKG_ATTR_SIZES, &sizes);
+
+	if (status != SEC_E_OK) {
+		return status;
+	}
+
+	size_t user_plus_realm_length = strlen(user_plus_realm);
+	int msgSize = 4 + user_plus_realm_length;
+	char *msg = malloc((sizes.cbSecurityTrailer + msgSize + sizes.cbBlockSize) * sizeof(char));
+	msg[sizes.cbSecurityTrailer + 0] = 1;
+	msg[sizes.cbSecurityTrailer + 1] = 0;
+	msg[sizes.cbSecurityTrailer + 2] = 0;
+	msg[sizes.cbSecurityTrailer + 3] = 0;
+	memcpy(&msg[sizes.cbSecurityTrailer + 4], user_plus_realm, user_plus_realm_length);
+
+	SecBuffer wrapBufs[3];
+	SecBufferDesc wrapBufDesc;
+	wrapBufDesc.cBuffers = 3;
+	wrapBufDesc.pBuffers = wrapBufs;
+	wrapBufDesc.ulVersion = SECBUFFER_VERSION;
+
+	wrapBufs[0].cbBuffer = sizes.cbSecurityTrailer;
+	wrapBufs[0].BufferType = SECBUFFER_TOKEN;
+	wrapBufs[0].pvBuffer = msg;
+
+	wrapBufs[1].cbBuffer = msgSize;
+	wrapBufs[1].BufferType = SECBUFFER_DATA;
+	wrapBufs[1].pvBuffer = msg + sizes.cbSecurityTrailer;
+
+	wrapBufs[2].cbBuffer = sizes.cbBlockSize;
+	wrapBufs[2].BufferType = SECBUFFER_PADDING;
+	wrapBufs[2].pvBuffer = msg + sizes.cbSecurityTrailer + msgSize;
+
+	status = call_sspi_encrypt_message(context, SECQOP_WRAP_NO_ENCRYPT, &wrapBufDesc, 0);
+	if (status != SEC_E_OK) {
+		free(msg);
+		return status;
+	}
+
+	*buffer_length = wrapBufs[0].cbBuffer + wrapBufs[1].cbBuffer + wrapBufs[2].cbBuffer;
+	*buffer = malloc(*buffer_length);
+
+	memcpy(*buffer, wrapBufs[0].pvBuffer, wrapBufs[0].cbBuffer);
+	memcpy(*buffer + wrapBufs[0].cbBuffer, wrapBufs[1].pvBuffer, wrapBufs[1].cbBuffer);
+	memcpy(*buffer + wrapBufs[0].cbBuffer + wrapBufs[1].cbBuffer, wrapBufs[2].pvBuffer, wrapBufs[2].cbBuffer);
+
+	free(msg);
+	return SEC_E_OK;
+}

vendor/gopkg.in/mgo.v2/internal/sasl/sasl_windows.go

@@ -0,0 +1,142 @@
+package sasl
+
+// #include "sasl_windows.h"
+import "C"
+
+import (
+	"fmt"
+	"strings"
+	"sync"
+	"unsafe"
+)
+
+type saslStepper interface {
+	Step(serverData []byte) (clientData []byte, done bool, err error)
+	Close()
+}
+
+type saslSession struct {
+	// Credentials
+	mech          string
+	service       string
+	host          string
+	userPlusRealm string
+	target        string
+	domain        string
+
+	// Internal state
+	authComplete bool
+	errored      bool
+	step         int
+
+	// C internal state
+	credHandle C.CredHandle
+	context    C.CtxtHandle
+	hasContext C.int
+
+	// Keep track of pointers we need to explicitly free
+	stringsToFree []*C.char
+}
+
+var initError error
+var initOnce sync.Once
+
+func initSSPI() {
+	rc := C.load_secur32_dll()
+	if rc != 0 {
+		initError = fmt.Errorf("Error loading libraries: %v", rc)
+	}
+}
+
+func New(username, password, mechanism, service, host string) (saslStepper, error) {
+	initOnce.Do(initSSPI)
+	ss := &saslSession{mech: mechanism, hasContext: 0, userPlusRealm: username}
+	if service == "" {
+		service = "mongodb"
+	}
+	if i := strings.Index(host, ":"); i >= 0 {
+		host = host[:i]
+	}
+	ss.service = service
+	ss.host = host
+
+	usernameComponents := strings.Split(username, "@")
+	if len(usernameComponents) < 2 {
+		return nil, fmt.Errorf("Username '%v' doesn't contain a realm!", username)
+	}
+	user := usernameComponents[0]
+	ss.domain = usernameComponents[1]
+	ss.target = fmt.Sprintf("%s/%s", ss.service, ss.host)
+
+	var status C.SECURITY_STATUS
+	// Step 0: call AcquireCredentialsHandle to get a nice SSPI CredHandle
+	if len(password) > 0 {
+		status = C.sspi_acquire_credentials_handle(&ss.credHandle, ss.cstr(user), ss.cstr(password), ss.cstr(ss.domain))
+	} else {
+		status = C.sspi_acquire_credentials_handle(&ss.credHandle, ss.cstr(user), nil, ss.cstr(ss.domain))
+	}
+	if status != C.SEC_E_OK {
+		ss.errored = true
+		return nil, fmt.Errorf("Couldn't create new SSPI client, error code %v", status)
+	}
+	return ss, nil
+}
+
+func (ss *saslSession) cstr(s string) *C.char {
+	cstr := C.CString(s)
+	ss.stringsToFree = append(ss.stringsToFree, cstr)
+	return cstr
+}
+
+func (ss *saslSession) Close() {
+	for _, cstr := range ss.stringsToFree {
+		C.free(unsafe.Pointer(cstr))
+	}
+}
+
+func (ss *saslSession) Step(serverData []byte) (clientData []byte, done bool, err error) {
+	ss.step++
+	if ss.step > 10 {
+		return nil, false, fmt.Errorf("too many SSPI steps without authentication")
+	}
+	var buffer C.PVOID
+	var bufferLength C.ULONG
+	var outBuffer C.PVOID
+	var outBufferLength C.ULONG
+	if len(serverData) > 0 {
+		buffer = (C.PVOID)(unsafe.Pointer(&serverData[0]))
+		bufferLength = C.ULONG(len(serverData))
+	}
+	var status C.int
+	if ss.authComplete {
+		// Step 3: last bit of magic to use the correct server credentials
+		status = C.sspi_send_client_authz_id(&ss.context, &outBuffer, &outBufferLength, ss.cstr(ss.userPlusRealm))
+	} else {
+		// Step 1 + Step 2: set up security context with the server and TGT
+		status = C.sspi_step(&ss.credHandle, ss.hasContext, &ss.context, buffer, bufferLength, &outBuffer, &outBufferLength, ss.cstr(ss.target))
+	}
+	if outBuffer != C.PVOID(nil) {
+		defer C.free(unsafe.Pointer(outBuffer))
+	}
+	if status != C.SEC_E_OK && status != C.SEC_I_CONTINUE_NEEDED {
+		ss.errored = true
+		return nil, false, ss.handleSSPIErrorCode(status)
+	}
+
+	clientData = C.GoBytes(unsafe.Pointer(outBuffer), C.int(outBufferLength))
+	if status == C.SEC_E_OK {
+		ss.authComplete = true
+		return clientData, true, nil
+	} else {
+		ss.hasContext = 1
+		return clientData, false, nil
+	}
+}
+
+func (ss *saslSession) handleSSPIErrorCode(code C.int) error {
+	switch {
+	case code == C.SEC_E_TARGET_UNKNOWN:
+		return fmt.Errorf("Target %v@%v not found", ss.target, ss.domain)
+	}
+	return fmt.Errorf("Unknown error doing step %v, error code %v", ss.step, code)
+}

vendor/gopkg.in/mgo.v2/internal/sasl/sasl_windows.h

@@ -0,0 +1,7 @@
+#include <windows.h>
+
+#include "sspi_windows.h"
+
+SECURITY_STATUS SEC_ENTRY sspi_acquire_credentials_handle(CredHandle* cred_handle, char* username, char* password, char* domain);
+int sspi_step(CredHandle* cred_handle, int has_context, CtxtHandle* context, PVOID buffer, ULONG buffer_length, PVOID* out_buffer, ULONG* out_buffer_length, char* target);
+int sspi_send_client_authz_id(CtxtHandle* context, PVOID* buffer, ULONG* buffer_length, char* user_plus_realm);

vendor/gopkg.in/mgo.v2/internal/sasl/sspi_windows.c

@@ -0,0 +1,96 @@
+// Code adapted from the NodeJS kerberos library:
+// 
+//   https://github.com/christkv/kerberos/tree/master/lib/win32/kerberos_sspi.c
+//
+// Under the terms of the Apache License, Version 2.0:
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+#include <stdlib.h>
+
+#include "sspi_windows.h"
+
+static HINSTANCE sspi_secur32_dll = NULL;
+
+int load_secur32_dll()
+{
+	sspi_secur32_dll = LoadLibrary("secur32.dll");
+	if (sspi_secur32_dll == NULL) {
+		return GetLastError();
+	}
+	return 0;
+}
+
+SECURITY_STATUS SEC_ENTRY call_sspi_encrypt_message(PCtxtHandle phContext, unsigned long fQOP, PSecBufferDesc pMessage, unsigned long MessageSeqNo)
+{
+	if (sspi_secur32_dll == NULL) {
+		return -1;
+	}
+	encryptMessage_fn pfn_encryptMessage = (encryptMessage_fn) GetProcAddress(sspi_secur32_dll, "EncryptMessage");
+	if (!pfn_encryptMessage) {
+		return -2;
+	}
+	return (*pfn_encryptMessage)(phContext, fQOP, pMessage, MessageSeqNo);
+}
+
+SECURITY_STATUS SEC_ENTRY call_sspi_acquire_credentials_handle(
+	LPSTR pszPrincipal, LPSTR pszPackage, unsigned long fCredentialUse,
+        void *pvLogonId, void *pAuthData, SEC_GET_KEY_FN pGetKeyFn, void *pvGetKeyArgument,
+        PCredHandle phCredential, PTimeStamp ptsExpiry)
+{
+	if (sspi_secur32_dll == NULL) {
+		return -1;
+	}
+	acquireCredentialsHandle_fn pfn_acquireCredentialsHandle;
+#ifdef _UNICODE
+	pfn_acquireCredentialsHandle = (acquireCredentialsHandle_fn) GetProcAddress(sspi_secur32_dll, "AcquireCredentialsHandleW");
+#else
+	pfn_acquireCredentialsHandle = (acquireCredentialsHandle_fn) GetProcAddress(sspi_secur32_dll, "AcquireCredentialsHandleA");
+#endif
+	if (!pfn_acquireCredentialsHandle) {
+		return -2;
+	}
+	return (*pfn_acquireCredentialsHandle)(
+		pszPrincipal, pszPackage, fCredentialUse, pvLogonId, pAuthData,
+	        pGetKeyFn, pvGetKeyArgument, phCredential, ptsExpiry);
+}
+
+SECURITY_STATUS SEC_ENTRY call_sspi_initialize_security_context(
+	PCredHandle phCredential, PCtxtHandle phContext, LPSTR pszTargetName,
+	unsigned long fContextReq, unsigned long Reserved1, unsigned long TargetDataRep,
+	PSecBufferDesc pInput, unsigned long Reserved2, PCtxtHandle phNewContext,
+	PSecBufferDesc pOutput, unsigned long *pfContextAttr, PTimeStamp ptsExpiry)
+{
+	if (sspi_secur32_dll == NULL) {
+		return -1;
+	}
+	initializeSecurityContext_fn pfn_initializeSecurityContext;
+#ifdef _UNICODE
+	pfn_initializeSecurityContext = (initializeSecurityContext_fn) GetProcAddress(sspi_secur32_dll, "InitializeSecurityContextW");
+#else
+	pfn_initializeSecurityContext = (initializeSecurityContext_fn) GetProcAddress(sspi_secur32_dll, "InitializeSecurityContextA");
+#endif
+	if (!pfn_initializeSecurityContext) {
+		return -2;
+	}
+	return (*pfn_initializeSecurityContext)(
+		phCredential, phContext, pszTargetName, fContextReq, Reserved1, TargetDataRep,
+		pInput, Reserved2, phNewContext, pOutput, pfContextAttr, ptsExpiry);
+}
+
+SECURITY_STATUS SEC_ENTRY call_sspi_query_context_attributes(PCtxtHandle phContext, unsigned long ulAttribute, void *pBuffer)
+{
+	if (sspi_secur32_dll == NULL) {
+		return -1;
+	}
+	queryContextAttributes_fn pfn_queryContextAttributes;
+#ifdef _UNICODE
+	pfn_queryContextAttributes = (queryContextAttributes_fn) GetProcAddress(sspi_secur32_dll, "QueryContextAttributesW");
+#else
+	pfn_queryContextAttributes = (queryContextAttributes_fn) GetProcAddress(sspi_secur32_dll, "QueryContextAttributesA");
+#endif
+	if (!pfn_queryContextAttributes) {
+		return -2;
+	}
+	return (*pfn_queryContextAttributes)(phContext, ulAttribute, pBuffer);
+}

vendor/gopkg.in/mgo.v2/internal/sasl/sspi_windows.h

@@ -0,0 +1,70 @@
+// Code adapted from the NodeJS kerberos library:
+// 
+//   https://github.com/christkv/kerberos/tree/master/lib/win32/kerberos_sspi.h
+//
+// Under the terms of the Apache License, Version 2.0:
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+#ifndef SSPI_WINDOWS_H
+#define SSPI_WINDOWS_H
+
+#define SECURITY_WIN32 1
+
+#include <windows.h>
+#include <sspi.h>
+
+int load_secur32_dll();
+
+SECURITY_STATUS SEC_ENTRY call_sspi_encrypt_message(PCtxtHandle phContext, unsigned long fQOP, PSecBufferDesc pMessage, unsigned long MessageSeqNo);
+
+typedef DWORD (WINAPI *encryptMessage_fn)(PCtxtHandle phContext, ULONG fQOP, PSecBufferDesc pMessage, ULONG MessageSeqNo);
+
+SECURITY_STATUS SEC_ENTRY call_sspi_acquire_credentials_handle(
+    LPSTR pszPrincipal,             // Name of principal
+    LPSTR pszPackage,               // Name of package
+    unsigned long fCredentialUse,   // Flags indicating use
+    void *pvLogonId,                // Pointer to logon ID
+    void *pAuthData,                // Package specific data
+    SEC_GET_KEY_FN pGetKeyFn,       // Pointer to GetKey() func
+    void *pvGetKeyArgument,         // Value to pass to GetKey()
+    PCredHandle phCredential,       // (out) Cred Handle
+    PTimeStamp ptsExpiry            // (out) Lifetime (optional)
+);
+
+typedef DWORD (WINAPI *acquireCredentialsHandle_fn)(
+    LPSTR pszPrincipal, LPSTR pszPackage, unsigned long fCredentialUse,
+    void *pvLogonId, void *pAuthData, SEC_GET_KEY_FN pGetKeyFn, void *pvGetKeyArgument,
+    PCredHandle phCredential, PTimeStamp ptsExpiry
+);
+
+SECURITY_STATUS SEC_ENTRY call_sspi_initialize_security_context(
+    PCredHandle phCredential,       // Cred to base context
+    PCtxtHandle phContext,          // Existing context (OPT)
+    LPSTR pszTargetName,            // Name of target
+    unsigned long fContextReq,      // Context Requirements
+    unsigned long Reserved1,        // Reserved, MBZ
+    unsigned long TargetDataRep,    // Data rep of target
+    PSecBufferDesc pInput,          // Input Buffers
+    unsigned long Reserved2,        // Reserved, MBZ
+    PCtxtHandle phNewContext,       // (out) New Context handle
+    PSecBufferDesc pOutput,         // (inout) Output Buffers
+    unsigned long *pfContextAttr,   // (out) Context attrs
+    PTimeStamp ptsExpiry            // (out) Life span (OPT)
+);
+
+typedef DWORD (WINAPI *initializeSecurityContext_fn)(
+    PCredHandle phCredential, PCtxtHandle phContext, LPSTR pszTargetName, unsigned long fContextReq,
+    unsigned long Reserved1, unsigned long TargetDataRep, PSecBufferDesc pInput, unsigned long Reserved2,
+    PCtxtHandle phNewContext, PSecBufferDesc pOutput, unsigned long *pfContextAttr, PTimeStamp ptsExpiry);
+
+SECURITY_STATUS SEC_ENTRY call_sspi_query_context_attributes(
+    PCtxtHandle phContext,          // Context to query
+    unsigned long ulAttribute,      // Attribute to query
+    void *pBuffer                   // Buffer for attributes
+);
+
+typedef DWORD (WINAPI *queryContextAttributes_fn)(
+    PCtxtHandle phContext, unsigned long ulAttribute, void *pBuffer);
+
+#endif // SSPI_WINDOWS_H

vendor/gopkg.in/mgo.v2/internal/scram/scram.go

@@ -0,0 +1,266 @@
+// mgo - MongoDB driver for Go
+//
+// Copyright (c) 2014 - Gustavo Niemeyer <gustavo@niemeyer.net>
+//
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this
+//    list of conditions and the following disclaimer.
+// 2. Redistributions in binary form must reproduce the above copyright notice,
+//    this list of conditions and the following disclaimer in the documentation
+//    and/or other materials provided with the distribution.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+// ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Pacakage scram implements a SCRAM-{SHA-1,etc} client per RFC5802.
+//
+// http://tools.ietf.org/html/rfc5802
+//
+package scram
+
+import (
+	"bytes"
+	"crypto/hmac"
+	"crypto/rand"
+	"encoding/base64"
+	"fmt"
+	"hash"
+	"strconv"
+	"strings"
+)
+
+// Client implements a SCRAM-* client (SCRAM-SHA-1, SCRAM-SHA-256, etc).
+//
+// A Client may be used within a SASL conversation with logic resembling:
+//
+//    var in []byte
+//    var client = scram.NewClient(sha1.New, user, pass)
+//    for client.Step(in) {
+//            out := client.Out()
+//            // send out to server
+//            in := serverOut
+//    }
+//    if client.Err() != nil {
+//            // auth failed
+//    }
+//
+type Client struct {
+	newHash func() hash.Hash
+
+	user string
+	pass string
+	step int
+	out  bytes.Buffer
+	err  error
+
+	clientNonce []byte
+	serverNonce []byte
+	saltedPass  []byte
+	authMsg     bytes.Buffer
+}
+
+// NewClient returns a new SCRAM-* client with the provided hash algorithm.
+//
+// For SCRAM-SHA-1, for example, use:
+//
+//    client := scram.NewClient(sha1.New, user, pass)
+//
+func NewClient(newHash func() hash.Hash, user, pass string) *Client {
+	c := &Client{
+		newHash: newHash,
+		user:    user,
+		pass:    pass,
+	}
+	c.out.Grow(256)
+	c.authMsg.Grow(256)
+	return c
+}
+
+// Out returns the data to be sent to the server in the current step.
+func (c *Client) Out() []byte {
+	if c.out.Len() == 0 {
+		return nil
+	}
+	return c.out.Bytes()
+}
+
+// Err returns the error that ocurred, or nil if there were no errors.
+func (c *Client) Err() error {
+	return c.err
+}
+
+// SetNonce sets the client nonce to the provided value.
+// If not set, the nonce is generated automatically out of crypto/rand on the first step.
+func (c *Client) SetNonce(nonce []byte) {
+	c.clientNonce = nonce
+}
+
+var escaper = strings.NewReplacer("=", "=3D", ",", "=2C")
+
+// Step processes the incoming data from the server and makes the
+// next round of data for the server available via Client.Out.
+// Step returns false if there are no errors and more data is
+// still expected.
+func (c *Client) Step(in []byte) bool {
+	c.out.Reset()
+	if c.step > 2 || c.err != nil {
+		return false
+	}
+	c.step++
+	switch c.step {
+	case 1:
+		c.err = c.step1(in)
+	case 2:
+		c.err = c.step2(in)
+	case 3:
+		c.err = c.step3(in)
+	}
+	return c.step > 2 || c.err != nil
+}
+
+func (c *Client) step1(in []byte) error {
+	if len(c.clientNonce) == 0 {
+		const nonceLen = 6
+		buf := make([]byte, nonceLen + b64.EncodedLen(nonceLen))
+		if _, err := rand.Read(buf[:nonceLen]); err != nil {
+			return fmt.Errorf("cannot read random SCRAM-SHA-1 nonce from operating system: %v", err)
+		}
+		c.clientNonce = buf[nonceLen:]
+		b64.Encode(c.clientNonce, buf[:nonceLen])
+	}
+	c.authMsg.WriteString("n=")
+	escaper.WriteString(&c.authMsg, c.user)
+	c.authMsg.WriteString(",r=")
+	c.authMsg.Write(c.clientNonce)
+
+	c.out.WriteString("n,,")
+	c.out.Write(c.authMsg.Bytes())
+	return nil
+}
+
+var b64 = base64.StdEncoding
+
+func (c *Client) step2(in []byte) error {
+	c.authMsg.WriteByte(',')
+	c.authMsg.Write(in)
+
+	fields := bytes.Split(in, []byte(","))
+	if len(fields) != 3 {
+		return fmt.Errorf("expected 3 fields in first SCRAM-SHA-1 server message, got %d: %q", len(fields), in)
+	}
+	if !bytes.HasPrefix(fields[0], []byte("r=")) || len(fields[0]) < 2 {
+		return fmt.Errorf("server sent an invalid SCRAM-SHA-1 nonce: %q", fields[0])
+	}
+	if !bytes.HasPrefix(fields[1], []byte("s=")) || len(fields[1]) < 6 {
+		return fmt.Errorf("server sent an invalid SCRAM-SHA-1 salt: %q", fields[1])
+	}
+	if !bytes.HasPrefix(fields[2], []byte("i=")) || len(fields[2]) < 6 {
+		return fmt.Errorf("server sent an invalid SCRAM-SHA-1 iteration count: %q", fields[2])
+	}
+
+	c.serverNonce = fields[0][2:]
+	if !bytes.HasPrefix(c.serverNonce, c.clientNonce) {
+		return fmt.Errorf("server SCRAM-SHA-1 nonce is not prefixed by client nonce: got %q, want %q+\"...\"", c.serverNonce, c.clientNonce)
+	}
+
+	salt := make([]byte, b64.DecodedLen(len(fields[1][2:])))
+	n, err := b64.Decode(salt, fields[1][2:])
+	if err != nil {
+		return fmt.Errorf("cannot decode SCRAM-SHA-1 salt sent by server: %q", fields[1])
+	}
+	salt = salt[:n]
+	iterCount, err := strconv.Atoi(string(fields[2][2:]))
+	if err != nil {
+		return fmt.Errorf("server sent an invalid SCRAM-SHA-1 iteration count: %q", fields[2])
+	}
+	c.saltPassword(salt, iterCount)
+
+	c.authMsg.WriteString(",c=biws,r=")
+	c.authMsg.Write(c.serverNonce)
+
+	c.out.WriteString("c=biws,r=")
+	c.out.Write(c.serverNonce)
+	c.out.WriteString(",p=")
+	c.out.Write(c.clientProof())
+	return nil
+}
+
+func (c *Client) step3(in []byte) error {
+	var isv, ise bool
+	var fields = bytes.Split(in, []byte(","))
+	if len(fields) == 1 {
+		isv = bytes.HasPrefix(fields[0], []byte("v="))
+		ise = bytes.HasPrefix(fields[0], []byte("e="))
+	}
+	if ise {
+		return fmt.Errorf("SCRAM-SHA-1 authentication error: %s", fields[0][2:])
+	} else if !isv {
+		return fmt.Errorf("unsupported SCRAM-SHA-1 final message from server: %q", in)
+	}
+	if !bytes.Equal(c.serverSignature(), fields[0][2:]) {
+		return fmt.Errorf("cannot authenticate SCRAM-SHA-1 server signature: %q", fields[0][2:])
+	}
+	return nil
+}
+
+func (c *Client) saltPassword(salt []byte, iterCount int) {
+	mac := hmac.New(c.newHash, []byte(c.pass))
+	mac.Write(salt)
+	mac.Write([]byte{0, 0, 0, 1})
+	ui := mac.Sum(nil)
+	hi := make([]byte, len(ui))
+	copy(hi, ui)
+	for i := 1; i < iterCount; i++ {
+		mac.Reset()
+		mac.Write(ui)
+		mac.Sum(ui[:0])
+		for j, b := range ui {
+			hi[j] ^= b
+		}
+	}
+	c.saltedPass = hi
+}
+
+func (c *Client) clientProof() []byte {
+	mac := hmac.New(c.newHash, c.saltedPass)
+	mac.Write([]byte("Client Key"))
+	clientKey := mac.Sum(nil)
+	hash := c.newHash()
+	hash.Write(clientKey)
+	storedKey := hash.Sum(nil)
+	mac = hmac.New(c.newHash, storedKey)
+	mac.Write(c.authMsg.Bytes())
+	clientProof := mac.Sum(nil)
+	for i, b := range clientKey {
+		clientProof[i] ^= b
+	}
+	clientProof64 := make([]byte, b64.EncodedLen(len(clientProof)))
+	b64.Encode(clientProof64, clientProof)
+	return clientProof64
+}
+
+func (c *Client) serverSignature() []byte {
+	mac := hmac.New(c.newHash, c.saltedPass)
+	mac.Write([]byte("Server Key"))
+	serverKey := mac.Sum(nil)
+
+	mac = hmac.New(c.newHash, serverKey)
+	mac.Write(c.authMsg.Bytes())
+	serverSignature := mac.Sum(nil)
+
+	encoded := make([]byte, b64.EncodedLen(len(serverSignature)))
+	b64.Encode(encoded, serverSignature)
+	return encoded
+}

vendor/gopkg.in/mgo.v2/log.go

@@ -0,0 +1,133 @@
+// mgo - MongoDB driver for Go
+//
+// Copyright (c) 2010-2012 - Gustavo Niemeyer <gustavo@niemeyer.net>
+//
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this
+//    list of conditions and the following disclaimer.
+// 2. Redistributions in binary form must reproduce the above copyright notice,
+//    this list of conditions and the following disclaimer in the documentation
+//    and/or other materials provided with the distribution.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+// ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package mgo
+
+import (
+	"fmt"
+	"sync"
+)
+
+// ---------------------------------------------------------------------------
+// Logging integration.
+
+// Avoid importing the log type information unnecessarily.  There's a small cost
+// associated with using an interface rather than the type.  Depending on how
+// often the logger is plugged in, it would be worth using the type instead.
+type log_Logger interface {
+	Output(calldepth int, s string) error
+}
+
+var (
+	globalLogger log_Logger
+	globalDebug  bool
+	globalMutex  sync.Mutex
+)
+
+// RACE WARNING: There are known data races when logging, which are manually
+// silenced when the race detector is in use. These data races won't be
+// observed in typical use, because logging is supposed to be set up once when
+// the application starts. Having raceDetector as a constant, the compiler
+// should elide the locks altogether in actual use.
+
+// Specify the *log.Logger object where log messages should be sent to.
+func SetLogger(logger log_Logger) {
+	if raceDetector {
+		globalMutex.Lock()
+		defer globalMutex.Unlock()
+	}
+	globalLogger = logger
+}
+
+// Enable the delivery of debug messages to the logger.  Only meaningful
+// if a logger is also set.
+func SetDebug(debug bool) {
+	if raceDetector {
+		globalMutex.Lock()
+		defer globalMutex.Unlock()
+	}
+	globalDebug = debug
+}
+
+func log(v ...interface{}) {
+	if raceDetector {
+		globalMutex.Lock()
+		defer globalMutex.Unlock()
+	}
+	if globalLogger != nil {
+		globalLogger.Output(2, fmt.Sprint(v...))
+	}
+}
+
+func logln(v ...interface{}) {
+	if raceDetector {
+		globalMutex.Lock()
+		defer globalMutex.Unlock()
+	}
+	if globalLogger != nil {
+		globalLogger.Output(2, fmt.Sprintln(v...))
+	}
+}
+
+func logf(format string, v ...interface{}) {
+	if raceDetector {
+		globalMutex.Lock()
+		defer globalMutex.Unlock()
+	}
+	if globalLogger != nil {
+		globalLogger.Output(2, fmt.Sprintf(format, v...))
+	}
+}
+
+func debug(v ...interface{}) {
+	if raceDetector {
+		globalMutex.Lock()
+		defer globalMutex.Unlock()
+	}
+	if globalDebug && globalLogger != nil {
+		globalLogger.Output(2, fmt.Sprint(v...))
+	}
+}
+
+func debugln(v ...interface{}) {
+	if raceDetector {
+		globalMutex.Lock()
+		defer globalMutex.Unlock()
+	}
+	if globalDebug && globalLogger != nil {
+		globalLogger.Output(2, fmt.Sprintln(v...))
+	}
+}
+
+func debugf(format string, v ...interface{}) {
+	if raceDetector {
+		globalMutex.Lock()
+		defer globalMutex.Unlock()
+	}
+	if globalDebug && globalLogger != nil {
+		globalLogger.Output(2, fmt.Sprintf(format, v...))
+	}
+}

vendor/gopkg.in/mgo.v2/queue.go

@@ -0,0 +1,91 @@
+// mgo - MongoDB driver for Go
+//
+// Copyright (c) 2010-2012 - Gustavo Niemeyer <gustavo@niemeyer.net>
+//
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this
+//    list of conditions and the following disclaimer.
+// 2. Redistributions in binary form must reproduce the above copyright notice,
+//    this list of conditions and the following disclaimer in the documentation
+//    and/or other materials provided with the distribution.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+// ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package mgo
+
+type queue struct {
+	elems               []interface{}
+	nelems, popi, pushi int
+}
+
+func (q *queue) Len() int {
+	return q.nelems
+}
+
+func (q *queue) Push(elem interface{}) {
+	//debugf("Pushing(pushi=%d popi=%d cap=%d): %#v\n",
+	//       q.pushi, q.popi, len(q.elems), elem)
+	if q.nelems == len(q.elems) {
+		q.expand()
+	}
+	q.elems[q.pushi] = elem
+	q.nelems++
+	q.pushi = (q.pushi + 1) % len(q.elems)
+	//debugf(" Pushed(pushi=%d popi=%d cap=%d): %#v\n",
+	//       q.pushi, q.popi, len(q.elems), elem)
+}
+
+func (q *queue) Pop() (elem interface{}) {
+	//debugf("Popping(pushi=%d popi=%d cap=%d)\n",
+	//       q.pushi, q.popi, len(q.elems))
+	if q.nelems == 0 {
+		return nil
+	}
+	elem = q.elems[q.popi]
+	q.elems[q.popi] = nil // Help GC.
+	q.nelems--
+	q.popi = (q.popi + 1) % len(q.elems)
+	//debugf(" Popped(pushi=%d popi=%d cap=%d): %#v\n",
+	//       q.pushi, q.popi, len(q.elems), elem)
+	return elem
+}
+
+func (q *queue) expand() {
+	curcap := len(q.elems)
+	var newcap int
+	if curcap == 0 {
+		newcap = 8
+	} else if curcap < 1024 {
+		newcap = curcap * 2
+	} else {
+		newcap = curcap + (curcap / 4)
+	}
+	elems := make([]interface{}, newcap)
+
+	if q.popi == 0 {
+		copy(elems, q.elems)
+		q.pushi = curcap
+	} else {
+		newpopi := newcap - (curcap - q.popi)
+		copy(elems, q.elems[:q.popi])
+		copy(elems[newpopi:], q.elems[q.popi:])
+		q.popi = newpopi
+	}
+	for i := range q.elems {
+		q.elems[i] = nil // Help GC.
+	}
+	q.elems = elems
+}

vendor/gopkg.in/mgo.v2/raceoff.go

@@ -0,0 +1,5 @@
+// +build !race
+
+package mgo
+
+const raceDetector = false

vendor/gopkg.in/mgo.v2/raceon.go

@@ -0,0 +1,5 @@
+// +build race
+
+package mgo
+
+const raceDetector = true

vendor/gopkg.in/mgo.v2/saslimpl.go

@@ -0,0 +1,11 @@
+//+build sasl
+
+package mgo
+
+import (
+	"gopkg.in/mgo.v2/internal/sasl"
+)
+
+func saslNew(cred Credential, host string) (saslStepper, error) {
+	return sasl.New(cred.Username, cred.Password, cred.Mechanism, cred.Service, host)
+}

vendor/gopkg.in/mgo.v2/saslstub.go

@@ -0,0 +1,11 @@
+//+build !sasl
+
+package mgo
+
+import (
+	"fmt"
+)
+
+func saslNew(cred Credential, host string) (saslStepper, error) {
+	return nil, fmt.Errorf("SASL support not enabled during build (-tags sasl)")
+}

vendor/gopkg.in/mgo.v2/server.go

@@ -0,0 +1,463 @@
+// mgo - MongoDB driver for Go
+//
+// Copyright (c) 2010-2012 - Gustavo Niemeyer <gustavo@niemeyer.net>
+//
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this
+//    list of conditions and the following disclaimer.
+// 2. Redistributions in binary form must reproduce the above copyright notice,
+//    this list of conditions and the following disclaimer in the documentation
+//    and/or other materials provided with the distribution.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+// ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package mgo
+
+import (
+	"errors"
+	"net"
+	"sort"
+	"sync"
+	"time"
+
+	"gopkg.in/mgo.v2/bson"
+)
+
+// ---------------------------------------------------------------------------
+// Mongo server encapsulation.
+
+type mongoServer struct {
+	sync.RWMutex
+	Addr          string
+	ResolvedAddr  string
+	tcpaddr       *net.TCPAddr
+	unusedSockets []*mongoSocket
+	liveSockets   []*mongoSocket
+	closed        bool
+	abended       bool
+	sync          chan bool
+	dial          dialer
+	pingValue     time.Duration
+	pingIndex     int
+	pingCount     uint32
+	pingWindow    [6]time.Duration
+	info          *mongoServerInfo
+}
+
+type dialer struct {
+	old func(addr net.Addr) (net.Conn, error)
+	new func(addr *ServerAddr) (net.Conn, error)
+}
+
+func (dial dialer) isSet() bool {
+	return dial.old != nil || dial.new != nil
+}
+
+type mongoServerInfo struct {
+	Master         bool
+	Mongos         bool
+	Tags           bson.D
+	MaxWireVersion int
+	SetName        string
+}
+
+var defaultServerInfo mongoServerInfo
+
+func newServer(addr string, tcpaddr *net.TCPAddr, sync chan bool, dial dialer) *mongoServer {
+	server := &mongoServer{
+		Addr:         addr,
+		ResolvedAddr: tcpaddr.String(),
+		tcpaddr:      tcpaddr,
+		sync:         sync,
+		dial:         dial,
+		info:         &defaultServerInfo,
+		pingValue:    time.Hour, // Push it back before an actual ping.
+	}
+	go server.pinger(true)
+	return server
+}
+
+var errPoolLimit = errors.New("per-server connection limit reached")
+var errServerClosed = errors.New("server was closed")
+
+// AcquireSocket returns a socket for communicating with the server.
+// This will attempt to reuse an old connection, if one is available. Otherwise,
+// it will establish a new one. The returned socket is owned by the call site,
+// and will return to the cache when the socket has its Release method called
+// the same number of times as AcquireSocket + Acquire were called for it.
+// If the poolLimit argument is greater than zero and the number of sockets in
+// use in this server is greater than the provided limit, errPoolLimit is
+// returned.
+func (server *mongoServer) AcquireSocket(poolLimit int, timeout time.Duration) (socket *mongoSocket, abended bool, err error) {
+	for {
+		server.Lock()
+		abended = server.abended
+		if server.closed {
+			server.Unlock()
+			return nil, abended, errServerClosed
+		}
+		n := len(server.unusedSockets)
+		if poolLimit > 0 && len(server.liveSockets)-n >= poolLimit {
+			server.Unlock()
+			return nil, false, errPoolLimit
+		}
+		if n > 0 {
+			socket = server.unusedSockets[n-1]
+			server.unusedSockets[n-1] = nil // Help GC.
+			server.unusedSockets = server.unusedSockets[:n-1]
+			info := server.info
+			server.Unlock()
+			err = socket.InitialAcquire(info, timeout)
+			if err != nil {
+				continue
+			}
+		} else {
+			server.Unlock()
+			socket, err = server.Connect(timeout)
+			if err == nil {
+				server.Lock()
+				// We've waited for the Connect, see if we got
+				// closed in the meantime
+				if server.closed {
+					server.Unlock()
+					socket.Release()
+					socket.Close()
+					return nil, abended, errServerClosed
+				}
+				server.liveSockets = append(server.liveSockets, socket)
+				server.Unlock()
+			}
+		}
+		return
+	}
+	panic("unreachable")
+}
+
+// Connect establishes a new connection to the server. This should
+// generally be done through server.AcquireSocket().
+func (server *mongoServer) Connect(timeout time.Duration) (*mongoSocket, error) {
+	server.RLock()
+	master := server.info.Master
+	dial := server.dial
+	server.RUnlock()
+
+	logf("Establishing new connection to %s (timeout=%s)...", server.Addr, timeout)
+	var conn net.Conn
+	var err error
+	switch {
+	case !dial.isSet():
+		// Cannot do this because it lacks timeout support. :-(
+		//conn, err = net.DialTCP("tcp", nil, server.tcpaddr)
+		conn, err = net.DialTimeout("tcp", server.ResolvedAddr, timeout)
+		if tcpconn, ok := conn.(*net.TCPConn); ok {
+			tcpconn.SetKeepAlive(true)
+		} else if err == nil {
+			panic("internal error: obtained TCP connection is not a *net.TCPConn!?")
+		}
+	case dial.old != nil:
+		conn, err = dial.old(server.tcpaddr)
+	case dial.new != nil:
+		conn, err = dial.new(&ServerAddr{server.Addr, server.tcpaddr})
+	default:
+		panic("dialer is set, but both dial.old and dial.new are nil")
+	}
+	if err != nil {
+		logf("Connection to %s failed: %v", server.Addr, err.Error())
+		return nil, err
+	}
+	logf("Connection to %s established.", server.Addr)
+
+	stats.conn(+1, master)
+	return newSocket(server, conn, timeout), nil
+}
+
+// Close forces closing all sockets that are alive, whether
+// they're currently in use or not.
+func (server *mongoServer) Close() {
+	server.Lock()
+	server.closed = true
+	liveSockets := server.liveSockets
+	unusedSockets := server.unusedSockets
+	server.liveSockets = nil
+	server.unusedSockets = nil
+	server.Unlock()
+	logf("Connections to %s closing (%d live sockets).", server.Addr, len(liveSockets))
+	for i, s := range liveSockets {
+		s.Close()
+		liveSockets[i] = nil
+	}
+	for i := range unusedSockets {
+		unusedSockets[i] = nil
+	}
+}
+
+// RecycleSocket puts socket back into the unused cache.
+func (server *mongoServer) RecycleSocket(socket *mongoSocket) {
+	server.Lock()
+	if !server.closed {
+		server.unusedSockets = append(server.unusedSockets, socket)
+	}
+	server.Unlock()
+}
+
+func removeSocket(sockets []*mongoSocket, socket *mongoSocket) []*mongoSocket {
+	for i, s := range sockets {
+		if s == socket {
+			copy(sockets[i:], sockets[i+1:])
+			n := len(sockets) - 1
+			sockets[n] = nil
+			sockets = sockets[:n]
+			break
+		}
+	}
+	return sockets
+}
+
+// AbendSocket notifies the server that the given socket has terminated
+// abnormally, and thus should be discarded rather than cached.
+func (server *mongoServer) AbendSocket(socket *mongoSocket) {
+	server.Lock()
+	server.abended = true
+	if server.closed {
+		server.Unlock()
+		return
+	}
+	server.liveSockets = removeSocket(server.liveSockets, socket)
+	server.unusedSockets = removeSocket(server.unusedSockets, socket)
+	server.Unlock()
+	// Maybe just a timeout, but suggest a cluster sync up just in case.
+	select {
+	case server.sync <- true:
+	default:
+	}
+}
+
+func (server *mongoServer) SetInfo(info *mongoServerInfo) {
+	server.Lock()
+	server.info = info
+	server.Unlock()
+}
+
+func (server *mongoServer) Info() *mongoServerInfo {
+	server.Lock()
+	info := server.info
+	server.Unlock()
+	return info
+}
+
+func (server *mongoServer) hasTags(serverTags []bson.D) bool {
+NextTagSet:
+	for _, tags := range serverTags {
+	NextReqTag:
+		for _, req := range tags {
+			for _, has := range server.info.Tags {
+				if req.Name == has.Name {
+					if req.Value == has.Value {
+						continue NextReqTag
+					}
+					continue NextTagSet
+				}
+			}
+			continue NextTagSet
+		}
+		return true
+	}
+	return false
+}
+
+var pingDelay = 15 * time.Second
+
+func (server *mongoServer) pinger(loop bool) {
+	var delay time.Duration
+	if raceDetector {
+		// This variable is only ever touched by tests.
+		globalMutex.Lock()
+		delay = pingDelay
+		globalMutex.Unlock()
+	} else {
+		delay = pingDelay
+	}
+	op := queryOp{
+		collection: "admin.$cmd",
+		query:      bson.D{{"ping", 1}},
+		flags:      flagSlaveOk,
+		limit:      -1,
+	}
+	for {
+		if loop {
+			time.Sleep(delay)
+		}
+		op := op
+		socket, _, err := server.AcquireSocket(0, delay)
+		if err == nil {
+			start := time.Now()
+			_, _ = socket.SimpleQuery(&op)
+			delay := time.Now().Sub(start)
+
+			server.pingWindow[server.pingIndex] = delay
+			server.pingIndex = (server.pingIndex + 1) % len(server.pingWindow)
+			server.pingCount++
+			var max time.Duration
+			for i := 0; i < len(server.pingWindow) && uint32(i) < server.pingCount; i++ {
+				if server.pingWindow[i] > max {
+					max = server.pingWindow[i]
+				}
+			}
+			socket.Release()
+			server.Lock()
+			if server.closed {
+				loop = false
+			}
+			server.pingValue = max
+			server.Unlock()
+			logf("Ping for %s is %d ms", server.Addr, max/time.Millisecond)
+		} else if err == errServerClosed {
+			return
+		}
+		if !loop {
+			return
+		}
+	}
+}
+
+type mongoServerSlice []*mongoServer
+
+func (s mongoServerSlice) Len() int {
+	return len(s)
+}
+
+func (s mongoServerSlice) Less(i, j int) bool {
+	return s[i].ResolvedAddr < s[j].ResolvedAddr
+}
+
+func (s mongoServerSlice) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+
+func (s mongoServerSlice) Sort() {
+	sort.Sort(s)
+}
+
+func (s mongoServerSlice) Search(resolvedAddr string) (i int, ok bool) {
+	n := len(s)
+	i = sort.Search(n, func(i int) bool {
+		return s[i].ResolvedAddr >= resolvedAddr
+	})
+	return i, i != n && s[i].ResolvedAddr == resolvedAddr
+}
+
+type mongoServers struct {
+	slice mongoServerSlice
+}
+
+func (servers *mongoServers) Search(resolvedAddr string) (server *mongoServer) {
+	if i, ok := servers.slice.Search(resolvedAddr); ok {
+		return servers.slice[i]
+	}
+	return nil
+}
+
+func (servers *mongoServers) Add(server *mongoServer) {
+	servers.slice = append(servers.slice, server)
+	servers.slice.Sort()
+}
+
+func (servers *mongoServers) Remove(other *mongoServer) (server *mongoServer) {
+	if i, found := servers.slice.Search(other.ResolvedAddr); found {
+		server = servers.slice[i]
+		copy(servers.slice[i:], servers.slice[i+1:])
+		n := len(servers.slice) - 1
+		servers.slice[n] = nil // Help GC.
+		servers.slice = servers.slice[:n]
+	}
+	return
+}
+
+func (servers *mongoServers) Slice() []*mongoServer {
+	return ([]*mongoServer)(servers.slice)
+}
+
+func (servers *mongoServers) Get(i int) *mongoServer {
+	return servers.slice[i]
+}
+
+func (servers *mongoServers) Len() int {
+	return len(servers.slice)
+}
+
+func (servers *mongoServers) Empty() bool {
+	return len(servers.slice) == 0
+}
+
+func (servers *mongoServers) HasMongos() bool {
+	for _, s := range servers.slice {
+		if s.Info().Mongos {
+			return true
+		}
+	}
+	return false
+}
+
+// BestFit returns the best guess of what would be the most interesting
+// server to perform operations on at this point in time.
+func (servers *mongoServers) BestFit(mode Mode, serverTags []bson.D) *mongoServer {
+	var best *mongoServer
+	for _, next := range servers.slice {
+		if best == nil {
+			best = next
+			best.RLock()
+			if serverTags != nil && !next.info.Mongos && !best.hasTags(serverTags) {
+				best.RUnlock()
+				best = nil
+			}
+			continue
+		}
+		next.RLock()
+		swap := false
+		switch {
+		case serverTags != nil && !next.info.Mongos && !next.hasTags(serverTags):
+			// Must have requested tags.
+		case mode == Secondary && next.info.Master && !next.info.Mongos:
+			// Must be a secondary or mongos.
+		case next.info.Master != best.info.Master && mode != Nearest:
+			// Prefer slaves, unless the mode is PrimaryPreferred.
+			swap = (mode == PrimaryPreferred) != best.info.Master
+		case absDuration(next.pingValue-best.pingValue) > 15*time.Millisecond:
+			// Prefer nearest server.
+			swap = next.pingValue < best.pingValue
+		case len(next.liveSockets)-len(next.unusedSockets) < len(best.liveSockets)-len(best.unusedSockets):
+			// Prefer servers with less connections.
+			swap = true
+		}
+		if swap {
+			best.RUnlock()
+			best = next
+		} else {
+			next.RUnlock()
+		}
+	}
+	if best != nil {
+		best.RUnlock()
+	}
+	return best
+}
+
+func absDuration(d time.Duration) time.Duration {
+	if d < 0 {
+		return -d
+	}
+	return d
+}

vendor/gopkg.in/mgo.v2/socket.go

@@ -0,0 +1,707 @@
+// mgo - MongoDB driver for Go
+//
+// Copyright (c) 2010-2012 - Gustavo Niemeyer <gustavo@niemeyer.net>
+//
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this
+//    list of conditions and the following disclaimer.
+// 2. Redistributions in binary form must reproduce the above copyright notice,
+//    this list of conditions and the following disclaimer in the documentation
+//    and/or other materials provided with the distribution.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+// ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package mgo
+
+import (
+	"errors"
+	"fmt"
+	"net"
+	"sync"
+	"time"
+
+	"gopkg.in/mgo.v2/bson"
+)
+
+type replyFunc func(err error, reply *replyOp, docNum int, docData []byte)
+
+type mongoSocket struct {
+	sync.Mutex
+	server        *mongoServer // nil when cached
+	conn          net.Conn
+	timeout       time.Duration
+	addr          string // For debugging only.
+	nextRequestId uint32
+	replyFuncs    map[uint32]replyFunc
+	references    int
+	creds         []Credential
+	logout        []Credential
+	cachedNonce   string
+	gotNonce      sync.Cond
+	dead          error
+	serverInfo    *mongoServerInfo
+}
+
+type queryOpFlags uint32
+
+const (
+	_ queryOpFlags = 1 << iota
+	flagTailable
+	flagSlaveOk
+	flagLogReplay
+	flagNoCursorTimeout
+	flagAwaitData
+)
+
+type queryOp struct {
+	collection string
+	query      interface{}
+	skip       int32
+	limit      int32
+	selector   interface{}
+	flags      queryOpFlags
+	replyFunc  replyFunc
+
+	mode       Mode
+	options    queryWrapper
+	hasOptions bool
+	serverTags []bson.D
+}
+
+type queryWrapper struct {
+	Query          interface{} "$query"
+	OrderBy        interface{} "$orderby,omitempty"
+	Hint           interface{} "$hint,omitempty"
+	Explain        bool        "$explain,omitempty"
+	Snapshot       bool        "$snapshot,omitempty"
+	ReadPreference bson.D      "$readPreference,omitempty"
+	MaxScan        int         "$maxScan,omitempty"
+	MaxTimeMS      int         "$maxTimeMS,omitempty"
+	Comment        string      "$comment,omitempty"
+}
+
+func (op *queryOp) finalQuery(socket *mongoSocket) interface{} {
+	if op.flags&flagSlaveOk != 0 && socket.ServerInfo().Mongos {
+		var modeName string
+		switch op.mode {
+		case Strong:
+			modeName = "primary"
+		case Monotonic, Eventual:
+			modeName = "secondaryPreferred"
+		case PrimaryPreferred:
+			modeName = "primaryPreferred"
+		case Secondary:
+			modeName = "secondary"
+		case SecondaryPreferred:
+			modeName = "secondaryPreferred"
+		case Nearest:
+			modeName = "nearest"
+		default:
+			panic(fmt.Sprintf("unsupported read mode: %d", op.mode))
+		}
+		op.hasOptions = true
+		op.options.ReadPreference = make(bson.D, 0, 2)
+		op.options.ReadPreference = append(op.options.ReadPreference, bson.DocElem{"mode", modeName})
+		if len(op.serverTags) > 0 {
+			op.options.ReadPreference = append(op.options.ReadPreference, bson.DocElem{"tags", op.serverTags})
+		}
+	}
+	if op.hasOptions {
+		if op.query == nil {
+			var empty bson.D
+			op.options.Query = empty
+		} else {
+			op.options.Query = op.query
+		}
+		debugf("final query is %#v\n", &op.options)
+		return &op.options
+	}
+	return op.query
+}
+
+type getMoreOp struct {
+	collection string
+	limit      int32
+	cursorId   int64
+	replyFunc  replyFunc
+}
+
+type replyOp struct {
+	flags     uint32
+	cursorId  int64
+	firstDoc  int32
+	replyDocs int32
+}
+
+type insertOp struct {
+	collection string        // "database.collection"
+	documents  []interface{} // One or more documents to insert
+	flags      uint32
+}
+
+type updateOp struct {
+	Collection string      `bson:"-"` // "database.collection"
+	Selector   interface{} `bson:"q"`
+	Update     interface{} `bson:"u"`
+	Flags      uint32      `bson:"-"`
+	Multi      bool        `bson:"multi,omitempty"`
+	Upsert     bool        `bson:"upsert,omitempty"`
+}
+
+type deleteOp struct {
+	Collection string      `bson:"-"` // "database.collection"
+	Selector   interface{} `bson:"q"`
+	Flags      uint32      `bson:"-"`
+	Limit      int         `bson:"limit"`
+}
+
+type killCursorsOp struct {
+	cursorIds []int64
+}
+
+type requestInfo struct {
+	bufferPos int
+	replyFunc replyFunc
+}
+
+func newSocket(server *mongoServer, conn net.Conn, timeout time.Duration) *mongoSocket {
+	socket := &mongoSocket{
+		conn:       conn,
+		addr:       server.Addr,
+		server:     server,
+		replyFuncs: make(map[uint32]replyFunc),
+	}
+	socket.gotNonce.L = &socket.Mutex
+	if err := socket.InitialAcquire(server.Info(), timeout); err != nil {
+		panic("newSocket: InitialAcquire returned error: " + err.Error())
+	}
+	stats.socketsAlive(+1)
+	debugf("Socket %p to %s: initialized", socket, socket.addr)
+	socket.resetNonce()
+	go socket.readLoop()
+	return socket
+}
+
+// Server returns the server that the socket is associated with.
+// It returns nil while the socket is cached in its respective server.
+func (socket *mongoSocket) Server() *mongoServer {
+	socket.Lock()
+	server := socket.server
+	socket.Unlock()
+	return server
+}
+
+// ServerInfo returns details for the server at the time the socket
+// was initially acquired.
+func (socket *mongoSocket) ServerInfo() *mongoServerInfo {
+	socket.Lock()
+	serverInfo := socket.serverInfo
+	socket.Unlock()
+	return serverInfo
+}
+
+// InitialAcquire obtains the first reference to the socket, either
+// right after the connection is made or once a recycled socket is
+// being put back in use.
+func (socket *mongoSocket) InitialAcquire(serverInfo *mongoServerInfo, timeout time.Duration) error {
+	socket.Lock()
+	if socket.references > 0 {
+		panic("Socket acquired out of cache with references")
+	}
+	if socket.dead != nil {
+		dead := socket.dead
+		socket.Unlock()
+		return dead
+	}
+	socket.references++
+	socket.serverInfo = serverInfo
+	socket.timeout = timeout
+	stats.socketsInUse(+1)
+	stats.socketRefs(+1)
+	socket.Unlock()
+	return nil
+}
+
+// Acquire obtains an additional reference to the socket.
+// The socket will only be recycled when it's released as many
+// times as it's been acquired.
+func (socket *mongoSocket) Acquire() (info *mongoServerInfo) {
+	socket.Lock()
+	if socket.references == 0 {
+		panic("Socket got non-initial acquire with references == 0")
+	}
+	// We'll track references to dead sockets as well.
+	// Caller is still supposed to release the socket.
+	socket.references++
+	stats.socketRefs(+1)
+	serverInfo := socket.serverInfo
+	socket.Unlock()
+	return serverInfo
+}
+
+// Release decrements a socket reference. The socket will be
+// recycled once its released as many times as it's been acquired.
+func (socket *mongoSocket) Release() {
+	socket.Lock()
+	if socket.references == 0 {
+		panic("socket.Release() with references == 0")
+	}
+	socket.references--
+	stats.socketRefs(-1)
+	if socket.references == 0 {
+		stats.socketsInUse(-1)
+		server := socket.server
+		socket.Unlock()
+		socket.LogoutAll()
+		// If the socket is dead server is nil.
+		if server != nil {
+			server.RecycleSocket(socket)
+		}
+	} else {
+		socket.Unlock()
+	}
+}
+
+// SetTimeout changes the timeout used on socket operations.
+func (socket *mongoSocket) SetTimeout(d time.Duration) {
+	socket.Lock()
+	socket.timeout = d
+	socket.Unlock()
+}
+
+type deadlineType int
+
+const (
+	readDeadline  deadlineType = 1
+	writeDeadline deadlineType = 2
+)
+
+func (socket *mongoSocket) updateDeadline(which deadlineType) {
+	var when time.Time
+	if socket.timeout > 0 {
+		when = time.Now().Add(socket.timeout)
+	}
+	whichstr := ""
+	switch which {
+	case readDeadline | writeDeadline:
+		whichstr = "read/write"
+		socket.conn.SetDeadline(when)
+	case readDeadline:
+		whichstr = "read"
+		socket.conn.SetReadDeadline(when)
+	case writeDeadline:
+		whichstr = "write"
+		socket.conn.SetWriteDeadline(when)
+	default:
+		panic("invalid parameter to updateDeadline")
+	}
+	debugf("Socket %p to %s: updated %s deadline to %s ahead (%s)", socket, socket.addr, whichstr, socket.timeout, when)
+}
+
+// Close terminates the socket use.
+func (socket *mongoSocket) Close() {
+	socket.kill(errors.New("Closed explicitly"), false)
+}
+
+func (socket *mongoSocket) kill(err error, abend bool) {
+	socket.Lock()
+	if socket.dead != nil {
+		debugf("Socket %p to %s: killed again: %s (previously: %s)", socket, socket.addr, err.Error(), socket.dead.Error())
+		socket.Unlock()
+		return
+	}
+	logf("Socket %p to %s: closing: %s (abend=%v)", socket, socket.addr, err.Error(), abend)
+	socket.dead = err
+	socket.conn.Close()
+	stats.socketsAlive(-1)
+	replyFuncs := socket.replyFuncs
+	socket.replyFuncs = make(map[uint32]replyFunc)
+	server := socket.server
+	socket.server = nil
+	socket.gotNonce.Broadcast()
+	socket.Unlock()
+	for _, replyFunc := range replyFuncs {
+		logf("Socket %p to %s: notifying replyFunc of closed socket: %s", socket, socket.addr, err.Error())
+		replyFunc(err, nil, -1, nil)
+	}
+	if abend {
+		server.AbendSocket(socket)
+	}
+}
+
+func (socket *mongoSocket) SimpleQuery(op *queryOp) (data []byte, err error) {
+	var wait, change sync.Mutex
+	var replyDone bool
+	var replyData []byte
+	var replyErr error
+	wait.Lock()
+	op.replyFunc = func(err error, reply *replyOp, docNum int, docData []byte) {
+		change.Lock()
+		if !replyDone {
+			replyDone = true
+			replyErr = err
+			if err == nil {
+				replyData = docData
+			}
+		}
+		change.Unlock()
+		wait.Unlock()
+	}
+	err = socket.Query(op)
+	if err != nil {
+		return nil, err
+	}
+	wait.Lock()
+	change.Lock()
+	data = replyData
+	err = replyErr
+	change.Unlock()
+	return data, err
+}
+
+func (socket *mongoSocket) Query(ops ...interface{}) (err error) {
+
+	if lops := socket.flushLogout(); len(lops) > 0 {
+		ops = append(lops, ops...)
+	}
+
+	buf := make([]byte, 0, 256)
+
+	// Serialize operations synchronously to avoid interrupting
+	// other goroutines while we can't really be sending data.
+	// Also, record id positions so that we can compute request
+	// ids at once later with the lock already held.
+	requests := make([]requestInfo, len(ops))
+	requestCount := 0
+
+	for _, op := range ops {
+		debugf("Socket %p to %s: serializing op: %#v", socket, socket.addr, op)
+		if qop, ok := op.(*queryOp); ok {
+			if cmd, ok := qop.query.(*findCmd); ok {
+				debugf("Socket %p to %s: find command: %#v", socket, socket.addr, cmd)
+			}
+		}
+		start := len(buf)
+		var replyFunc replyFunc
+		switch op := op.(type) {
+
+		case *updateOp:
+			buf = addHeader(buf, 2001)
+			buf = addInt32(buf, 0) // Reserved
+			buf = addCString(buf, op.Collection)
+			buf = addInt32(buf, int32(op.Flags))
+			debugf("Socket %p to %s: serializing selector document: %#v", socket, socket.addr, op.Selector)
+			buf, err = addBSON(buf, op.Selector)
+			if err != nil {
+				return err
+			}
+			debugf("Socket %p to %s: serializing update document: %#v", socket, socket.addr, op.Update)
+			buf, err = addBSON(buf, op.Update)
+			if err != nil {
+				return err
+			}
+
+		case *insertOp:
+			buf = addHeader(buf, 2002)
+			buf = addInt32(buf, int32(op.flags))
+			buf = addCString(buf, op.collection)
+			for _, doc := range op.documents {
+				debugf("Socket %p to %s: serializing document for insertion: %#v", socket, socket.addr, doc)
+				buf, err = addBSON(buf, doc)
+				if err != nil {
+					return err
+				}
+			}
+
+		case *queryOp:
+			buf = addHeader(buf, 2004)
+			buf = addInt32(buf, int32(op.flags))
+			buf = addCString(buf, op.collection)
+			buf = addInt32(buf, op.skip)
+			buf = addInt32(buf, op.limit)
+			buf, err = addBSON(buf, op.finalQuery(socket))
+			if err != nil {
+				return err
+			}
+			if op.selector != nil {
+				buf, err = addBSON(buf, op.selector)
+				if err != nil {
+					return err
+				}
+			}
+			replyFunc = op.replyFunc
+
+		case *getMoreOp:
+			buf = addHeader(buf, 2005)
+			buf = addInt32(buf, 0) // Reserved
+			buf = addCString(buf, op.collection)
+			buf = addInt32(buf, op.limit)
+			buf = addInt64(buf, op.cursorId)
+			replyFunc = op.replyFunc
+
+		case *deleteOp:
+			buf = addHeader(buf, 2006)
+			buf = addInt32(buf, 0) // Reserved
+			buf = addCString(buf, op.Collection)
+			buf = addInt32(buf, int32(op.Flags))
+			debugf("Socket %p to %s: serializing selector document: %#v", socket, socket.addr, op.Selector)
+			buf, err = addBSON(buf, op.Selector)
+			if err != nil {
+				return err
+			}
+
+		case *killCursorsOp:
+			buf = addHeader(buf, 2007)
+			buf = addInt32(buf, 0) // Reserved
+			buf = addInt32(buf, int32(len(op.cursorIds)))
+			for _, cursorId := range op.cursorIds {
+				buf = addInt64(buf, cursorId)
+			}
+
+		default:
+			panic("internal error: unknown operation type")
+		}
+
+		setInt32(buf, start, int32(len(buf)-start))
+
+		if replyFunc != nil {
+			request := &requests[requestCount]
+			request.replyFunc = replyFunc
+			request.bufferPos = start
+			requestCount++
+		}
+	}
+
+	// Buffer is ready for the pipe.  Lock, allocate ids, and enqueue.
+
+	socket.Lock()
+	if socket.dead != nil {
+		dead := socket.dead
+		socket.Unlock()
+		debugf("Socket %p to %s: failing query, already closed: %s", socket, socket.addr, socket.dead.Error())
+		// XXX This seems necessary in case the session is closed concurrently
+		// with a query being performed, but it's not yet tested:
+		for i := 0; i != requestCount; i++ {
+			request := &requests[i]
+			if request.replyFunc != nil {
+				request.replyFunc(dead, nil, -1, nil)
+			}
+		}
+		return dead
+	}
+
+	wasWaiting := len(socket.replyFuncs) > 0
+
+	// Reserve id 0 for requests which should have no responses.
+	requestId := socket.nextRequestId + 1
+	if requestId == 0 {
+		requestId++
+	}
+	socket.nextRequestId = requestId + uint32(requestCount)
+	for i := 0; i != requestCount; i++ {
+		request := &requests[i]
+		setInt32(buf, request.bufferPos+4, int32(requestId))
+		socket.replyFuncs[requestId] = request.replyFunc
+		requestId++
+	}
+
+	debugf("Socket %p to %s: sending %d op(s) (%d bytes)", socket, socket.addr, len(ops), len(buf))
+	stats.sentOps(len(ops))
+
+	socket.updateDeadline(writeDeadline)
+	_, err = socket.conn.Write(buf)
+	if !wasWaiting && requestCount > 0 {
+		socket.updateDeadline(readDeadline)
+	}
+	socket.Unlock()
+	return err
+}
+
+func fill(r net.Conn, b []byte) error {
+	l := len(b)
+	n, err := r.Read(b)
+	for n != l && err == nil {
+		var ni int
+		ni, err = r.Read(b[n:])
+		n += ni
+	}
+	return err
+}
+
+// Estimated minimum cost per socket: 1 goroutine + memory for the largest
+// document ever seen.
+func (socket *mongoSocket) readLoop() {
+	p := make([]byte, 36) // 16 from header + 20 from OP_REPLY fixed fields
+	s := make([]byte, 4)
+	conn := socket.conn // No locking, conn never changes.
+	for {
+		err := fill(conn, p)
+		if err != nil {
+			socket.kill(err, true)
+			return
+		}
+
+		totalLen := getInt32(p, 0)
+		responseTo := getInt32(p, 8)
+		opCode := getInt32(p, 12)
+
+		// Don't use socket.server.Addr here.  socket is not
+		// locked and socket.server may go away.
+		debugf("Socket %p to %s: got reply (%d bytes)", socket, socket.addr, totalLen)
+
+		_ = totalLen
+
+		if opCode != 1 {
+			socket.kill(errors.New("opcode != 1, corrupted data?"), true)
+			return
+		}
+
+		reply := replyOp{
+			flags:     uint32(getInt32(p, 16)),
+			cursorId:  getInt64(p, 20),
+			firstDoc:  getInt32(p, 28),
+			replyDocs: getInt32(p, 32),
+		}
+
+		stats.receivedOps(+1)
+		stats.receivedDocs(int(reply.replyDocs))
+
+		socket.Lock()
+		replyFunc, ok := socket.replyFuncs[uint32(responseTo)]
+		if ok {
+			delete(socket.replyFuncs, uint32(responseTo))
+		}
+		socket.Unlock()
+
+		if replyFunc != nil && reply.replyDocs == 0 {
+			replyFunc(nil, &reply, -1, nil)
+		} else {
+			for i := 0; i != int(reply.replyDocs); i++ {
+				err := fill(conn, s)
+				if err != nil {
+					if replyFunc != nil {
+						replyFunc(err, nil, -1, nil)
+					}
+					socket.kill(err, true)
+					return
+				}
+
+				b := make([]byte, int(getInt32(s, 0)))
+
+				// copy(b, s) in an efficient way.
+				b[0] = s[0]
+				b[1] = s[1]
+				b[2] = s[2]
+				b[3] = s[3]
+
+				err = fill(conn, b[4:])
+				if err != nil {
+					if replyFunc != nil {
+						replyFunc(err, nil, -1, nil)
+					}
+					socket.kill(err, true)
+					return
+				}
+
+				if globalDebug && globalLogger != nil {
+					m := bson.M{}
+					if err := bson.Unmarshal(b, m); err == nil {
+						debugf("Socket %p to %s: received document: %#v", socket, socket.addr, m)
+					}
+				}
+
+				if replyFunc != nil {
+					replyFunc(nil, &reply, i, b)
+				}
+
+				// XXX Do bound checking against totalLen.
+			}
+		}
+
+		socket.Lock()
+		if len(socket.replyFuncs) == 0 {
+			// Nothing else to read for now. Disable deadline.
+			socket.conn.SetReadDeadline(time.Time{})
+		} else {
+			socket.updateDeadline(readDeadline)
+		}
+		socket.Unlock()
+
+		// XXX Do bound checking against totalLen.
+	}
+}
+
+var emptyHeader = []byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
+
+func addHeader(b []byte, opcode int) []byte {
+	i := len(b)
+	b = append(b, emptyHeader...)
+	// Enough for current opcodes.
+	b[i+12] = byte(opcode)
+	b[i+13] = byte(opcode >> 8)
+	return b
+}
+
+func addInt32(b []byte, i int32) []byte {
+	return append(b, byte(i), byte(i>>8), byte(i>>16), byte(i>>24))
+}
+
+func addInt64(b []byte, i int64) []byte {
+	return append(b, byte(i), byte(i>>8), byte(i>>16), byte(i>>24),
+		byte(i>>32), byte(i>>40), byte(i>>48), byte(i>>56))
+}
+
+func addCString(b []byte, s string) []byte {
+	b = append(b, []byte(s)...)
+	b = append(b, 0)
+	return b
+}
+
+func addBSON(b []byte, doc interface{}) ([]byte, error) {
+	if doc == nil {
+		return append(b, 5, 0, 0, 0, 0), nil
+	}
+	data, err := bson.Marshal(doc)
+	if err != nil {
+		return b, err
+	}
+	return append(b, data...), nil
+}
+
+func setInt32(b []byte, pos int, i int32) {
+	b[pos] = byte(i)
+	b[pos+1] = byte(i >> 8)
+	b[pos+2] = byte(i >> 16)
+	b[pos+3] = byte(i >> 24)
+}
+
+func getInt32(b []byte, pos int) int32 {
+	return (int32(b[pos+0])) |
+		(int32(b[pos+1]) << 8) |
+		(int32(b[pos+2]) << 16) |
+		(int32(b[pos+3]) << 24)
+}
+
+func getInt64(b []byte, pos int) int64 {
+	return (int64(b[pos+0])) |
+		(int64(b[pos+1]) << 8) |
+		(int64(b[pos+2]) << 16) |
+		(int64(b[pos+3]) << 24) |
+		(int64(b[pos+4]) << 32) |
+		(int64(b[pos+5]) << 40) |
+		(int64(b[pos+6]) << 48) |
+		(int64(b[pos+7]) << 56)
+}

vendor/gopkg.in/mgo.v2/stats.go

@@ -0,0 +1,147 @@
+// mgo - MongoDB driver for Go
+//
+// Copyright (c) 2010-2012 - Gustavo Niemeyer <gustavo@niemeyer.net>
+//
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this
+//    list of conditions and the following disclaimer.
+// 2. Redistributions in binary form must reproduce the above copyright notice,
+//    this list of conditions and the following disclaimer in the documentation
+//    and/or other materials provided with the distribution.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+// ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package mgo
+
+import (
+	"sync"
+)
+
+var stats *Stats
+var statsMutex sync.Mutex
+
+func SetStats(enabled bool) {
+	statsMutex.Lock()
+	if enabled {
+		if stats == nil {
+			stats = &Stats{}
+		}
+	} else {
+		stats = nil
+	}
+	statsMutex.Unlock()
+}
+
+func GetStats() (snapshot Stats) {
+	statsMutex.Lock()
+	snapshot = *stats
+	statsMutex.Unlock()
+	return
+}
+
+func ResetStats() {
+	statsMutex.Lock()
+	debug("Resetting stats")
+	old := stats
+	stats = &Stats{}
+	// These are absolute values:
+	stats.Clusters = old.Clusters
+	stats.SocketsInUse = old.SocketsInUse
+	stats.SocketsAlive = old.SocketsAlive
+	stats.SocketRefs = old.SocketRefs
+	statsMutex.Unlock()
+	return
+}
+
+type Stats struct {
+	Clusters     int
+	MasterConns  int
+	SlaveConns   int
+	SentOps      int
+	ReceivedOps  int
+	ReceivedDocs int
+	SocketsAlive int
+	SocketsInUse int
+	SocketRefs   int
+}
+
+func (stats *Stats) cluster(delta int) {
+	if stats != nil {
+		statsMutex.Lock()
+		stats.Clusters += delta
+		statsMutex.Unlock()
+	}
+}
+
+func (stats *Stats) conn(delta int, master bool) {
+	if stats != nil {
+		statsMutex.Lock()
+		if master {
+			stats.MasterConns += delta
+		} else {
+			stats.SlaveConns += delta
+		}
+		statsMutex.Unlock()
+	}
+}
+
+func (stats *Stats) sentOps(delta int) {
+	if stats != nil {
+		statsMutex.Lock()
+		stats.SentOps += delta
+		statsMutex.Unlock()
+	}
+}
+
+func (stats *Stats) receivedOps(delta int) {
+	if stats != nil {
+		statsMutex.Lock()
+		stats.ReceivedOps += delta
+		statsMutex.Unlock()
+	}
+}
+
+func (stats *Stats) receivedDocs(delta int) {
+	if stats != nil {
+		statsMutex.Lock()
+		stats.ReceivedDocs += delta
+		statsMutex.Unlock()
+	}
+}
+
+func (stats *Stats) socketsInUse(delta int) {
+	if stats != nil {
+		statsMutex.Lock()
+		stats.SocketsInUse += delta
+		statsMutex.Unlock()
+	}
+}
+
+func (stats *Stats) socketsAlive(delta int) {
+	if stats != nil {
+		statsMutex.Lock()
+		stats.SocketsAlive += delta
+		statsMutex.Unlock()
+	}
+}
+
+func (stats *Stats) socketRefs(delta int) {
+	if stats != nil {
+		statsMutex.Lock()
+		stats.SocketRefs += delta
+		statsMutex.Unlock()
+	}
+}

vendor/modules.txt

@@ -54,7 +54,7 @@ github.com/joho/godotenv/autoload
 # github.com/json-iterator/go v1.1.10
 ## explicit
 github.com/json-iterator/go
-# github.com/koding/cache v0.0.0-20140912085602-487fc0ca06f9
+# github.com/koding/cache v0.0.0-20161222233015-e8a81b0b3f20
 ## explicit
 github.com/koding/cache
 # github.com/leodido/go-urn v1.2.0
@@ -156,6 +156,13 @@ google.golang.org/protobuf/runtime/protoimpl
 # gopkg.in/gorp.v1 v1.7.1
 ## explicit
 gopkg.in/gorp.v1
+# gopkg.in/mgo.v2 v2.0.0-20190816093944-a6b53ec6cb22
+## explicit
+gopkg.in/mgo.v2
+gopkg.in/mgo.v2/bson
+gopkg.in/mgo.v2/internal/json
+gopkg.in/mgo.v2/internal/sasl
+gopkg.in/mgo.v2/internal/scram
 # gopkg.in/yaml.v2 v2.4.0
 ## explicit
 gopkg.in/yaml.v2