gecko-dev/netwerk/cache2/CacheIndex.h

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43 KiB
C++

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef CacheIndex__h__
#define CacheIndex__h__
#include "CacheLog.h"
#include "CacheFileIOManager.h"
#include "nsIRunnable.h"
#include "CacheHashUtils.h"
#include "nsICacheStorageService.h"
#include "nsICacheEntry.h"
#include "nsILoadContextInfo.h"
#include "nsIWeakReferenceUtils.h"
#include "nsTHashtable.h"
#include "nsThreadUtils.h"
#include "mozilla/IntegerPrintfMacros.h"
#include "mozilla/SHA1.h"
#include "mozilla/StaticMutex.h"
#include "mozilla/StaticPtr.h"
#include "mozilla/EndianUtils.h"
#include "mozilla/TimeStamp.h"
class nsIFile;
class nsIDirectoryEnumerator;
class nsITimer;
#ifdef DEBUG
# define DEBUG_STATS 1
#endif
namespace mozilla {
namespace net {
class CacheFileMetadata;
class FileOpenHelper;
class CacheIndexIterator;
const uint16_t kIndexTimeNotAvailable = 0xFFFFU;
const uint16_t kIndexTimeOutOfBound = 0xFFFEU;
typedef struct {
// Version of the index. The index must be ignored and deleted when the file
// on disk was written with a newer version.
uint32_t mVersion;
// Timestamp of time when the last successful write of the index started.
// During update process we use this timestamp for a quick validation of entry
// files. If last modified time of the file is lower than this timestamp, we
// skip parsing of such file since the information in index should be up to
// date.
uint32_t mTimeStamp;
// We set this flag as soon as possible after parsing index during startup
// and clean it after we write journal to disk during shutdown. We ignore the
// journal and start update process whenever this flag is set during index
// parsing.
uint32_t mIsDirty;
} CacheIndexHeader;
static_assert(sizeof(CacheIndexHeader::mVersion) +
sizeof(CacheIndexHeader::mTimeStamp) +
sizeof(CacheIndexHeader::mIsDirty) ==
sizeof(CacheIndexHeader),
"Unexpected sizeof(CacheIndexHeader)!");
#pragma pack(push, 4)
struct CacheIndexRecord {
SHA1Sum::Hash mHash;
uint32_t mFrecency;
OriginAttrsHash mOriginAttrsHash;
uint32_t mExpirationTime;
uint16_t mOnStartTime;
uint16_t mOnStopTime;
/*
* 1000 0000 0000 0000 0000 0000 0000 0000 : initialized
* 0100 0000 0000 0000 0000 0000 0000 0000 : anonymous
* 0010 0000 0000 0000 0000 0000 0000 0000 : removed
* 0001 0000 0000 0000 0000 0000 0000 0000 : dirty
* 0000 1000 0000 0000 0000 0000 0000 0000 : fresh
* 0000 0100 0000 0000 0000 0000 0000 0000 : pinned
* 0000 0010 0000 0000 0000 0000 0000 0000 : has cached alt data
* 0000 0001 0000 0000 0000 0000 0000 0000 : reserved
* 0000 0000 1111 1111 1111 1111 1111 1111 : file size (in kB)
*/
uint32_t mFlags;
CacheIndexRecord()
: mFrecency(0),
mOriginAttrsHash(0),
mExpirationTime(nsICacheEntry::NO_EXPIRATION_TIME),
mOnStartTime(kIndexTimeNotAvailable),
mOnStopTime(kIndexTimeNotAvailable),
mFlags(0) {}
};
#pragma pack(pop)
static_assert(sizeof(CacheIndexRecord::mHash) +
sizeof(CacheIndexRecord::mFrecency) +
sizeof(CacheIndexRecord::mOriginAttrsHash) +
sizeof(CacheIndexRecord::mExpirationTime) +
sizeof(CacheIndexRecord::mOnStartTime) +
sizeof(CacheIndexRecord::mOnStopTime) +
sizeof(CacheIndexRecord::mFlags) ==
sizeof(CacheIndexRecord),
"Unexpected sizeof(CacheIndexRecord)!");
class CacheIndexEntry : public PLDHashEntryHdr {
public:
typedef const SHA1Sum::Hash &KeyType;
typedef const SHA1Sum::Hash *KeyTypePointer;
explicit CacheIndexEntry(KeyTypePointer aKey) {
MOZ_COUNT_CTOR(CacheIndexEntry);
mRec = new CacheIndexRecord();
LOG(("CacheIndexEntry::CacheIndexEntry() - Created record [rec=%p]",
mRec.get()));
memcpy(&mRec->mHash, aKey, sizeof(SHA1Sum::Hash));
}
CacheIndexEntry(const CacheIndexEntry &aOther) {
MOZ_ASSERT_UNREACHABLE("CacheIndexEntry copy constructor is forbidden!");
}
~CacheIndexEntry() {
MOZ_COUNT_DTOR(CacheIndexEntry);
LOG(("CacheIndexEntry::~CacheIndexEntry() - Deleting record [rec=%p]",
mRec.get()));
}
// KeyEquals(): does this entry match this key?
bool KeyEquals(KeyTypePointer aKey) const {
return memcmp(&mRec->mHash, aKey, sizeof(SHA1Sum::Hash)) == 0;
}
// KeyToPointer(): Convert KeyType to KeyTypePointer
static KeyTypePointer KeyToPointer(KeyType aKey) { return &aKey; }
// HashKey(): calculate the hash number
static PLDHashNumber HashKey(KeyTypePointer aKey) {
return (reinterpret_cast<const uint32_t *>(aKey))[0];
}
// ALLOW_MEMMOVE can we move this class with memmove(), or do we have
// to use the copy constructor?
enum { ALLOW_MEMMOVE = true };
bool operator==(const CacheIndexEntry &aOther) const {
return KeyEquals(&aOther.mRec->mHash);
}
CacheIndexEntry &operator=(const CacheIndexEntry &aOther) {
MOZ_ASSERT(
memcmp(&mRec->mHash, &aOther.mRec->mHash, sizeof(SHA1Sum::Hash)) == 0);
mRec->mFrecency = aOther.mRec->mFrecency;
mRec->mExpirationTime = aOther.mRec->mExpirationTime;
mRec->mOriginAttrsHash = aOther.mRec->mOriginAttrsHash;
mRec->mOnStartTime = aOther.mRec->mOnStartTime;
mRec->mOnStopTime = aOther.mRec->mOnStopTime;
mRec->mFlags = aOther.mRec->mFlags;
return *this;
}
void InitNew() {
mRec->mFrecency = 0;
mRec->mExpirationTime = nsICacheEntry::NO_EXPIRATION_TIME;
mRec->mOriginAttrsHash = 0;
mRec->mOnStartTime = kIndexTimeNotAvailable;
mRec->mOnStopTime = kIndexTimeNotAvailable;
mRec->mFlags = 0;
}
void Init(OriginAttrsHash aOriginAttrsHash, bool aAnonymous, bool aPinned) {
MOZ_ASSERT(mRec->mFrecency == 0);
MOZ_ASSERT(mRec->mExpirationTime == nsICacheEntry::NO_EXPIRATION_TIME);
MOZ_ASSERT(mRec->mOriginAttrsHash == 0);
MOZ_ASSERT(mRec->mOnStartTime == kIndexTimeNotAvailable);
MOZ_ASSERT(mRec->mOnStopTime == kIndexTimeNotAvailable);
// When we init the entry it must be fresh and may be dirty
MOZ_ASSERT((mRec->mFlags & ~kDirtyMask) == kFreshMask);
mRec->mOriginAttrsHash = aOriginAttrsHash;
mRec->mFlags |= kInitializedMask;
if (aAnonymous) {
mRec->mFlags |= kAnonymousMask;
}
if (aPinned) {
mRec->mFlags |= kPinnedMask;
}
}
const SHA1Sum::Hash *Hash() const { return &mRec->mHash; }
bool IsInitialized() const { return !!(mRec->mFlags & kInitializedMask); }
mozilla::net::OriginAttrsHash OriginAttrsHash() const {
return mRec->mOriginAttrsHash;
}
bool Anonymous() const { return !!(mRec->mFlags & kAnonymousMask); }
bool IsRemoved() const { return !!(mRec->mFlags & kRemovedMask); }
void MarkRemoved() { mRec->mFlags |= kRemovedMask; }
bool IsDirty() const { return !!(mRec->mFlags & kDirtyMask); }
void MarkDirty() { mRec->mFlags |= kDirtyMask; }
void ClearDirty() { mRec->mFlags &= ~kDirtyMask; }
bool IsFresh() const { return !!(mRec->mFlags & kFreshMask); }
void MarkFresh() { mRec->mFlags |= kFreshMask; }
bool IsPinned() const { return !!(mRec->mFlags & kPinnedMask); }
void SetFrecency(uint32_t aFrecency) { mRec->mFrecency = aFrecency; }
uint32_t GetFrecency() const { return mRec->mFrecency; }
void SetExpirationTime(uint32_t aExpirationTime) {
mRec->mExpirationTime = aExpirationTime;
}
uint32_t GetExpirationTime() const { return mRec->mExpirationTime; }
void SetHasAltData(bool aHasAltData) {
aHasAltData ? mRec->mFlags |= kHasAltDataMask
: mRec->mFlags &= ~kHasAltDataMask;
}
bool GetHasAltData() const { return !!(mRec->mFlags & kHasAltDataMask); }
void SetOnStartTime(uint16_t aTime) { mRec->mOnStartTime = aTime; }
uint16_t GetOnStartTime() const { return mRec->mOnStartTime; }
void SetOnStopTime(uint16_t aTime) { mRec->mOnStopTime = aTime; }
uint16_t GetOnStopTime() const { return mRec->mOnStopTime; }
// Sets filesize in kilobytes.
void SetFileSize(uint32_t aFileSize) {
if (aFileSize > kFileSizeMask) {
LOG(
("CacheIndexEntry::SetFileSize() - FileSize is too large, "
"truncating to %u",
kFileSizeMask));
aFileSize = kFileSizeMask;
}
mRec->mFlags &= ~kFileSizeMask;
mRec->mFlags |= aFileSize;
}
// Returns filesize in kilobytes.
uint32_t GetFileSize() const { return GetFileSize(mRec); }
static uint32_t GetFileSize(CacheIndexRecord *aRec) {
return aRec->mFlags & kFileSizeMask;
}
static uint32_t IsPinned(CacheIndexRecord *aRec) {
return aRec->mFlags & kPinnedMask;
}
bool IsFileEmpty() const { return GetFileSize() == 0; }
void WriteToBuf(void *aBuf) {
uint8_t *ptr = static_cast<uint8_t *>(aBuf);
memcpy(ptr, mRec->mHash, sizeof(SHA1Sum::Hash));
ptr += sizeof(SHA1Sum::Hash);
NetworkEndian::writeUint32(ptr, mRec->mFrecency);
ptr += sizeof(uint32_t);
NetworkEndian::writeUint64(ptr, mRec->mOriginAttrsHash);
ptr += sizeof(uint64_t);
NetworkEndian::writeUint32(ptr, mRec->mExpirationTime);
ptr += sizeof(uint32_t);
NetworkEndian::writeUint16(ptr, mRec->mOnStartTime);
ptr += sizeof(uint16_t);
NetworkEndian::writeUint16(ptr, mRec->mOnStopTime);
ptr += sizeof(uint16_t);
// Dirty and fresh flags should never go to disk, since they make sense only
// during current session.
NetworkEndian::writeUint32(ptr, mRec->mFlags & ~(kDirtyMask | kFreshMask));
}
void ReadFromBuf(void *aBuf) {
const uint8_t *ptr = static_cast<const uint8_t *>(aBuf);
MOZ_ASSERT(memcmp(&mRec->mHash, ptr, sizeof(SHA1Sum::Hash)) == 0);
ptr += sizeof(SHA1Sum::Hash);
mRec->mFrecency = NetworkEndian::readUint32(ptr);
ptr += sizeof(uint32_t);
mRec->mOriginAttrsHash = NetworkEndian::readUint64(ptr);
ptr += sizeof(uint64_t);
mRec->mExpirationTime = NetworkEndian::readUint32(ptr);
ptr += sizeof(uint32_t);
mRec->mOnStartTime = NetworkEndian::readUint16(ptr);
ptr += sizeof(uint16_t);
mRec->mOnStopTime = NetworkEndian::readUint16(ptr);
ptr += sizeof(uint16_t);
mRec->mFlags = NetworkEndian::readUint32(ptr);
}
void Log() const {
LOG(
("CacheIndexEntry::Log() [this=%p, hash=%08x%08x%08x%08x%08x, fresh=%u,"
" initialized=%u, removed=%u, dirty=%u, anonymous=%u, "
"originAttrsHash=%" PRIx64 ", frecency=%u, expirationTime=%u, "
"hasAltData=%u, onStartTime=%u, onStopTime=%u, size=%u]",
this, LOGSHA1(mRec->mHash), IsFresh(), IsInitialized(), IsRemoved(),
IsDirty(), Anonymous(), OriginAttrsHash(), GetFrecency(),
GetExpirationTime(), GetHasAltData(), GetOnStartTime(),
GetOnStopTime(), GetFileSize()));
}
static bool RecordMatchesLoadContextInfo(CacheIndexRecord *aRec,
nsILoadContextInfo *aInfo) {
MOZ_ASSERT(aInfo);
if (!aInfo->IsPrivate() &&
GetOriginAttrsHash(*aInfo->OriginAttributesPtr()) ==
aRec->mOriginAttrsHash &&
aInfo->IsAnonymous() == !!(aRec->mFlags & kAnonymousMask)) {
return true;
}
return false;
}
// Memory reporting
size_t SizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf) const {
return mallocSizeOf(mRec.get());
}
size_t SizeOfIncludingThis(mozilla::MallocSizeOf mallocSizeOf) const {
return mallocSizeOf(this) + SizeOfExcludingThis(mallocSizeOf);
}
private:
friend class CacheIndexEntryUpdate;
friend class CacheIndex;
friend class CacheIndexEntryAutoManage;
static const uint32_t kInitializedMask = 0x80000000;
static const uint32_t kAnonymousMask = 0x40000000;
// This flag is set when the entry was removed. We need to keep this
// information in memory until we write the index file.
static const uint32_t kRemovedMask = 0x20000000;
// This flag is set when the information in memory is not in sync with the
// information in index file on disk.
static const uint32_t kDirtyMask = 0x10000000;
// This flag is set when the information about the entry is fresh, i.e.
// we've created or opened this entry during this session, or we've seen
// this entry during update or build process.
static const uint32_t kFreshMask = 0x08000000;
// Indicates a pinned entry.
static const uint32_t kPinnedMask = 0x04000000;
// Indicates there is cached alternative data in the entry.
static const uint32_t kHasAltDataMask = 0x02000000;
static const uint32_t kReservedMask = 0x01000000;
// FileSize in kilobytes
static const uint32_t kFileSizeMask = 0x00FFFFFF;
nsAutoPtr<CacheIndexRecord> mRec;
};
class CacheIndexEntryUpdate : public CacheIndexEntry {
public:
explicit CacheIndexEntryUpdate(CacheIndexEntry::KeyTypePointer aKey)
: CacheIndexEntry(aKey), mUpdateFlags(0) {
MOZ_COUNT_CTOR(CacheIndexEntryUpdate);
LOG(("CacheIndexEntryUpdate::CacheIndexEntryUpdate()"));
}
~CacheIndexEntryUpdate() {
MOZ_COUNT_DTOR(CacheIndexEntryUpdate);
LOG(("CacheIndexEntryUpdate::~CacheIndexEntryUpdate()"));
}
CacheIndexEntryUpdate &operator=(const CacheIndexEntry &aOther) {
MOZ_ASSERT(
memcmp(&mRec->mHash, &aOther.mRec->mHash, sizeof(SHA1Sum::Hash)) == 0);
mUpdateFlags = 0;
*(static_cast<CacheIndexEntry *>(this)) = aOther;
return *this;
}
void InitNew() {
mUpdateFlags = kFrecencyUpdatedMask | kExpirationUpdatedMask |
kHasAltDataUpdatedMask | kOnStartTimeUpdatedMask |
kOnStopTimeUpdatedMask | kFileSizeUpdatedMask;
CacheIndexEntry::InitNew();
}
void SetFrecency(uint32_t aFrecency) {
mUpdateFlags |= kFrecencyUpdatedMask;
CacheIndexEntry::SetFrecency(aFrecency);
}
void SetExpirationTime(uint32_t aExpirationTime) {
mUpdateFlags |= kExpirationUpdatedMask;
CacheIndexEntry::SetExpirationTime(aExpirationTime);
}
void SetHasAltData(bool aHasAltData) {
mUpdateFlags |= kHasAltDataUpdatedMask;
CacheIndexEntry::SetHasAltData(aHasAltData);
}
void SetOnStartTime(uint16_t aTime) {
mUpdateFlags |= kOnStartTimeUpdatedMask;
CacheIndexEntry::SetOnStartTime(aTime);
}
void SetOnStopTime(uint16_t aTime) {
mUpdateFlags |= kOnStopTimeUpdatedMask;
CacheIndexEntry::SetOnStopTime(aTime);
}
void SetFileSize(uint32_t aFileSize) {
mUpdateFlags |= kFileSizeUpdatedMask;
CacheIndexEntry::SetFileSize(aFileSize);
}
void ApplyUpdate(CacheIndexEntry *aDst) {
MOZ_ASSERT(
memcmp(&mRec->mHash, &aDst->mRec->mHash, sizeof(SHA1Sum::Hash)) == 0);
if (mUpdateFlags & kFrecencyUpdatedMask) {
aDst->mRec->mFrecency = mRec->mFrecency;
}
if (mUpdateFlags & kExpirationUpdatedMask) {
aDst->mRec->mExpirationTime = mRec->mExpirationTime;
}
aDst->mRec->mOriginAttrsHash = mRec->mOriginAttrsHash;
if (mUpdateFlags & kOnStartTimeUpdatedMask) {
aDst->mRec->mOnStartTime = mRec->mOnStartTime;
}
if (mUpdateFlags & kOnStopTimeUpdatedMask) {
aDst->mRec->mOnStopTime = mRec->mOnStopTime;
}
if (mUpdateFlags & kHasAltDataUpdatedMask &&
((aDst->mRec->mFlags ^ mRec->mFlags) & kHasAltDataMask)) {
// Toggle the bit if we need to.
aDst->mRec->mFlags ^= kHasAltDataMask;
}
if (mUpdateFlags & kFileSizeUpdatedMask) {
// Copy all flags except |HasAltData|.
aDst->mRec->mFlags |= (mRec->mFlags & ~kHasAltDataMask);
} else {
// Copy all flags except |HasAltData| and file size.
aDst->mRec->mFlags &= kFileSizeMask;
aDst->mRec->mFlags |= (mRec->mFlags & ~kHasAltDataMask & ~kFileSizeMask);
}
}
private:
static const uint32_t kFrecencyUpdatedMask = 0x00000001;
static const uint32_t kExpirationUpdatedMask = 0x00000002;
static const uint32_t kFileSizeUpdatedMask = 0x00000004;
static const uint32_t kHasAltDataUpdatedMask = 0x00000008;
static const uint32_t kOnStartTimeUpdatedMask = 0x00000010;
static const uint32_t kOnStopTimeUpdatedMask = 0x00000020;
uint32_t mUpdateFlags;
};
class CacheIndexStats {
public:
CacheIndexStats()
: mCount(0),
mNotInitialized(0),
mRemoved(0),
mDirty(0),
mFresh(0),
mEmpty(0),
mSize(0)
#ifdef DEBUG
,
mStateLogged(false),
mDisableLogging(false)
#endif
{
}
bool operator==(const CacheIndexStats &aOther) const {
return
#ifdef DEBUG
aOther.mStateLogged == mStateLogged &&
#endif
aOther.mCount == mCount && aOther.mNotInitialized == mNotInitialized &&
aOther.mRemoved == mRemoved && aOther.mDirty == mDirty &&
aOther.mFresh == mFresh && aOther.mEmpty == mEmpty &&
aOther.mSize == mSize;
}
#ifdef DEBUG
void DisableLogging() { mDisableLogging = true; }
#endif
void Log() {
LOG(
("CacheIndexStats::Log() [count=%u, notInitialized=%u, removed=%u, "
"dirty=%u, fresh=%u, empty=%u, size=%u]",
mCount, mNotInitialized, mRemoved, mDirty, mFresh, mEmpty, mSize));
}
void Clear() {
MOZ_ASSERT(!mStateLogged, "CacheIndexStats::Clear() - state logged!");
mCount = 0;
mNotInitialized = 0;
mRemoved = 0;
mDirty = 0;
mFresh = 0;
mEmpty = 0;
mSize = 0;
}
#ifdef DEBUG
bool StateLogged() { return mStateLogged; }
#endif
uint32_t Count() {
MOZ_ASSERT(!mStateLogged, "CacheIndexStats::Count() - state logged!");
return mCount;
}
uint32_t Dirty() {
MOZ_ASSERT(!mStateLogged, "CacheIndexStats::Dirty() - state logged!");
return mDirty;
}
uint32_t Fresh() {
MOZ_ASSERT(!mStateLogged, "CacheIndexStats::Fresh() - state logged!");
return mFresh;
}
uint32_t ActiveEntriesCount() {
MOZ_ASSERT(!mStateLogged,
"CacheIndexStats::ActiveEntriesCount() - state "
"logged!");
return mCount - mRemoved - mNotInitialized - mEmpty;
}
uint32_t Size() {
MOZ_ASSERT(!mStateLogged, "CacheIndexStats::Size() - state logged!");
return mSize;
}
void BeforeChange(const CacheIndexEntry *aEntry) {
#ifdef DEBUG_STATS
if (!mDisableLogging) {
LOG(("CacheIndexStats::BeforeChange()"));
Log();
}
#endif
MOZ_ASSERT(!mStateLogged,
"CacheIndexStats::BeforeChange() - state "
"logged!");
#ifdef DEBUG
mStateLogged = true;
#endif
if (aEntry) {
MOZ_ASSERT(mCount);
mCount--;
if (aEntry->IsDirty()) {
MOZ_ASSERT(mDirty);
mDirty--;
}
if (aEntry->IsFresh()) {
MOZ_ASSERT(mFresh);
mFresh--;
}
if (aEntry->IsRemoved()) {
MOZ_ASSERT(mRemoved);
mRemoved--;
} else {
if (!aEntry->IsInitialized()) {
MOZ_ASSERT(mNotInitialized);
mNotInitialized--;
} else {
if (aEntry->IsFileEmpty()) {
MOZ_ASSERT(mEmpty);
mEmpty--;
} else {
MOZ_ASSERT(mSize >= aEntry->GetFileSize());
mSize -= aEntry->GetFileSize();
}
}
}
}
}
void AfterChange(const CacheIndexEntry *aEntry) {
MOZ_ASSERT(mStateLogged,
"CacheIndexStats::AfterChange() - state not "
"logged!");
#ifdef DEBUG
mStateLogged = false;
#endif
if (aEntry) {
++mCount;
if (aEntry->IsDirty()) {
mDirty++;
}
if (aEntry->IsFresh()) {
mFresh++;
}
if (aEntry->IsRemoved()) {
mRemoved++;
} else {
if (!aEntry->IsInitialized()) {
mNotInitialized++;
} else {
if (aEntry->IsFileEmpty()) {
mEmpty++;
} else {
mSize += aEntry->GetFileSize();
}
}
}
}
#ifdef DEBUG_STATS
if (!mDisableLogging) {
LOG(("CacheIndexStats::AfterChange()"));
Log();
}
#endif
}
private:
uint32_t mCount;
uint32_t mNotInitialized;
uint32_t mRemoved;
uint32_t mDirty;
uint32_t mFresh;
uint32_t mEmpty;
uint32_t mSize;
#ifdef DEBUG
// We completely remove the data about an entry from the stats in
// BeforeChange() and set this flag to true. The entry is then modified,
// deleted or created and the data is again put into the stats and this flag
// set to false. Statistics must not be read during this time since the
// information is not correct.
bool mStateLogged;
// Disables logging in this instance of CacheIndexStats
bool mDisableLogging;
#endif
};
class CacheIndex final : public CacheFileIOListener, public nsIRunnable {
public:
NS_DECL_THREADSAFE_ISUPPORTS
NS_DECL_NSIRUNNABLE
CacheIndex();
static nsresult Init(nsIFile *aCacheDirectory);
static nsresult PreShutdown();
static nsresult Shutdown();
// Following methods can be called only on IO thread.
// Add entry to the index. The entry shouldn't be present in index. This
// method is called whenever a new handle for a new entry file is created. The
// newly created entry is not initialized and it must be either initialized
// with InitEntry() or removed with RemoveEntry().
static nsresult AddEntry(const SHA1Sum::Hash *aHash);
// Inform index about an existing entry that should be present in index. This
// method is called whenever a new handle for an existing entry file is
// created. Like in case of AddEntry(), either InitEntry() or RemoveEntry()
// must be called on the entry, since the entry is not initizlized if the
// index is outdated.
static nsresult EnsureEntryExists(const SHA1Sum::Hash *aHash);
// Initialize the entry. It MUST be present in index. Call to AddEntry() or
// EnsureEntryExists() must precede the call to this method.
static nsresult InitEntry(const SHA1Sum::Hash *aHash,
OriginAttrsHash aOriginAttrsHash, bool aAnonymous,
bool aPinned);
// Remove entry from index. The entry should be present in index.
static nsresult RemoveEntry(const SHA1Sum::Hash *aHash);
// Update some information in entry. The entry MUST be present in index and
// MUST be initialized. Call to AddEntry() or EnsureEntryExists() and to
// InitEntry() must precede the call to this method.
// Pass nullptr if the value didn't change.
static nsresult UpdateEntry(const SHA1Sum::Hash *aHash,
const uint32_t *aFrecency,
const uint32_t *aExpirationTime,
const bool *aHasAltData,
const uint16_t *aOnStartTime,
const uint16_t *aOnStopTime,
const uint32_t *aSize);
// Remove all entries from the index. Called when clearing the whole cache.
static nsresult RemoveAll();
enum EntryStatus { EXISTS = 0, DOES_NOT_EXIST = 1, DO_NOT_KNOW = 2 };
// Returns status of the entry in index for the given key. It can be called
// on any thread.
// If the optional aCB callback is given, the it will be called with a
// CacheIndexEntry only if _retval is EXISTS when the method returns.
static nsresult HasEntry(
const nsACString &aKey, EntryStatus *_retval,
const std::function<void(const CacheIndexEntry *)> &aCB = nullptr);
static nsresult HasEntry(
const SHA1Sum::Hash &hash, EntryStatus *_retval,
const std::function<void(const CacheIndexEntry *)> &aCB = nullptr);
// Returns a hash of the least important entry that should be evicted if the
// cache size is over limit and also returns a total number of all entries in
// the index minus the number of forced valid entries and unpinned entries
// that we encounter when searching (see below)
static nsresult GetEntryForEviction(bool aIgnoreEmptyEntries,
SHA1Sum::Hash *aHash, uint32_t *aCnt);
// Checks if a cache entry is currently forced valid. Used to prevent an entry
// (that has been forced valid) from being evicted when the cache size reaches
// its limit.
static bool IsForcedValidEntry(const SHA1Sum::Hash *aHash);
// Returns cache size in kB.
static nsresult GetCacheSize(uint32_t *_retval);
// Returns number of entry files in the cache
static nsresult GetEntryFileCount(uint32_t *_retval);
// Synchronously returns the disk occupation and number of entries
// per-context. Callable on any thread. It will ignore loadContextInfo and get
// stats for all entries if the aInfo is a nullptr.
static nsresult GetCacheStats(nsILoadContextInfo *aInfo, uint32_t *aSize,
uint32_t *aCount);
// Asynchronously gets the disk cache size, used for display in the UI.
static nsresult AsyncGetDiskConsumption(
nsICacheStorageConsumptionObserver *aObserver);
// Returns an iterator that returns entries matching a given context that were
// present in the index at the time this method was called. If aAddNew is true
// then the iterator will also return entries created after this call.
// NOTE: When some entry is removed from index it is removed also from the
// iterator regardless what aAddNew was passed.
static nsresult GetIterator(nsILoadContextInfo *aInfo, bool aAddNew,
CacheIndexIterator **_retval);
// Returns true if we _think_ that the index is up to date. I.e. the state is
// READY or WRITING and mIndexNeedsUpdate as well as mShuttingDown is false.
static nsresult IsUpToDate(bool *_retval);
// Called from CacheStorageService::Clear() and
// CacheFileContextEvictor::EvictEntries(), sets a flag that blocks
// notification to AsyncGetDiskConsumption.
static void OnAsyncEviction(bool aEvicting);
// Memory reporting
static size_t SizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf);
static size_t SizeOfIncludingThis(mozilla::MallocSizeOf mallocSizeOf);
private:
friend class CacheIndexEntryAutoManage;
friend class FileOpenHelper;
friend class CacheIndexIterator;
virtual ~CacheIndex();
NS_IMETHOD OnFileOpened(CacheFileHandle *aHandle, nsresult aResult) override;
nsresult OnFileOpenedInternal(FileOpenHelper *aOpener,
CacheFileHandle *aHandle, nsresult aResult);
NS_IMETHOD OnDataWritten(CacheFileHandle *aHandle, const char *aBuf,
nsresult aResult) override;
NS_IMETHOD OnDataRead(CacheFileHandle *aHandle, char *aBuf,
nsresult aResult) override;
NS_IMETHOD OnFileDoomed(CacheFileHandle *aHandle, nsresult aResult) override;
NS_IMETHOD OnEOFSet(CacheFileHandle *aHandle, nsresult aResult) override;
NS_IMETHOD OnFileRenamed(CacheFileHandle *aHandle, nsresult aResult) override;
nsresult InitInternal(nsIFile *aCacheDirectory);
void PreShutdownInternal();
// This method returns false when index is not initialized or is shut down.
bool IsIndexUsable();
// This method checks whether the entry has the same values of
// originAttributes and isAnonymous. We don't expect to find a collision
// since these values are part of the key that we hash and we use a strong
// hash function.
static bool IsCollision(CacheIndexEntry *aEntry,
OriginAttrsHash aOriginAttrsHash, bool aAnonymous);
// Checks whether any of the information about the entry has changed.
static bool HasEntryChanged(CacheIndexEntry *aEntry,
const uint32_t *aFrecency,
const uint32_t *aExpirationTime,
const bool *aHasAltData,
const uint16_t *aOnStartTime,
const uint16_t *aOnStopTime,
const uint32_t *aSize);
// Merge all pending operations from mPendingUpdates into mIndex.
void ProcessPendingOperations();
// Following methods perform writing of the index file.
//
// The index is written periodically, but not earlier than once in
// kMinDumpInterval and there must be at least kMinUnwrittenChanges
// differences between index on disk and in memory. Index is always first
// written to a temporary file and the old index file is replaced when the
// writing process succeeds.
//
// Starts writing of index when both limits (minimal delay between writes and
// minimum number of changes in index) were exceeded.
bool WriteIndexToDiskIfNeeded();
// Starts writing of index file.
void WriteIndexToDisk();
// Serializes part of mIndex hashtable to the write buffer a writes the buffer
// to the file.
void WriteRecords();
// Finalizes writing process.
void FinishWrite(bool aSucceeded);
// Following methods perform writing of the journal during shutdown. All these
// methods must be called only during shutdown since they write/delete files
// directly on the main thread instead of using CacheFileIOManager that does
// it asynchronously on IO thread. Journal contains only entries that are
// dirty, i.e. changes that are not present in the index file on the disk.
// When the log is written successfully, the dirty flag in index file is
// cleared.
nsresult GetFile(const nsACString &aName, nsIFile **_retval);
nsresult RemoveFile(const nsACString &aName);
void RemoveAllIndexFiles();
void RemoveJournalAndTempFile();
// Writes journal to the disk and clears dirty flag in index header.
nsresult WriteLogToDisk();
// Following methods perform reading of the index from the disk.
//
// Index is read at startup just after initializing the CacheIndex. There are
// 3 files used when manipulating with index: index file, journal file and
// a temporary file. All files contain the hash of the data, so we can check
// whether the content is valid and complete. Index file contains also a dirty
// flag in the index header which is unset on a clean shutdown. During opening
// and reading of the files we determine the status of the whole index from
// the states of the separate files. Following table shows all possible
// combinations:
//
// index, journal, tmpfile
// M * * - index is missing -> BUILD
// I * * - index is invalid -> BUILD
// D * * - index is dirty -> UPDATE
// C M * - index is dirty -> UPDATE
// C I * - unexpected state -> UPDATE
// C V E - unexpected state -> UPDATE
// C V M - index is up to date -> READY
//
// where the letters mean:
// * - any state
// E - file exists
// M - file is missing
// I - data is invalid (parsing failed or hash didn't match)
// D - dirty (data in index file is correct, but dirty flag is set)
// C - clean (index file is clean)
// V - valid (data in journal file is correct)
//
// Note: We accept the data from journal only when the index is up to date as
// a whole (i.e. C,V,M state).
//
// We rename the journal file to the temporary file as soon as possible after
// initial test to ensure that we start update process on the next startup if
// FF crashes during parsing of the index.
//
// Initiates reading index from disk.
void ReadIndexFromDisk();
// Starts reading data from index file.
void StartReadingIndex();
// Parses data read from index file.
void ParseRecords();
// Starts reading data from journal file.
void StartReadingJournal();
// Parses data read from journal file.
void ParseJournal();
// Merges entries from journal into mIndex.
void MergeJournal();
// In debug build this method checks that we have no fresh entry in mIndex
// after we finish reading index and before we process pending operations.
void EnsureNoFreshEntry();
// In debug build this method is called after processing pending operations
// to make sure mIndexStats contains correct information.
void EnsureCorrectStats();
// Finalizes reading process.
void FinishRead(bool aSucceeded);
// Following methods perform updating and building of the index.
// Timer callback that starts update or build process.
static void DelayedUpdate(nsITimer *aTimer, void *aClosure);
void DelayedUpdateLocked();
// Posts timer event that start update or build process.
nsresult ScheduleUpdateTimer(uint32_t aDelay);
nsresult SetupDirectoryEnumerator();
nsresult InitEntryFromDiskData(CacheIndexEntry *aEntry,
CacheFileMetadata *aMetaData,
int64_t aFileSize);
// Returns true when either a timer is scheduled or event is posted.
bool IsUpdatePending();
// Iterates through all files in entries directory that we didn't create/open
// during this session, parses them and adds the entries to the index.
void BuildIndex();
bool StartUpdatingIndexIfNeeded(bool aSwitchingToReadyState = false);
// Starts update or build process or fires a timer when it is too early after
// startup.
void StartUpdatingIndex(bool aRebuild);
// Iterates through all files in entries directory that we didn't create/open
// during this session and theirs last modified time is newer than timestamp
// in the index header. Parses the files and adds the entries to the index.
void UpdateIndex();
// Finalizes update or build process.
void FinishUpdate(bool aSucceeded);
void RemoveNonFreshEntries();
enum EState {
// Initial state in which the index is not usable
// Possible transitions:
// -> READING
INITIAL = 0,
// Index is being read from the disk.
// Possible transitions:
// -> INITIAL - We failed to dispatch a read event.
// -> BUILDING - No or corrupted index file was found.
// -> UPDATING - No or corrupted journal file was found.
// - Dirty flag was set in index header.
// -> READY - Index was read successfully or was interrupted by
// pre-shutdown.
// -> SHUTDOWN - This could happen only in case of pre-shutdown failure.
READING = 1,
// Index is being written to the disk.
// Possible transitions:
// -> READY - Writing of index finished or was interrupted by
// pre-shutdown..
// -> UPDATING - Writing of index finished, but index was found outdated
// during writing.
// -> SHUTDOWN - This could happen only in case of pre-shutdown failure.
WRITING = 2,
// Index is being build.
// Possible transitions:
// -> READY - Building of index finished or was interrupted by
// pre-shutdown.
// -> SHUTDOWN - This could happen only in case of pre-shutdown failure.
BUILDING = 3,
// Index is being updated.
// Possible transitions:
// -> READY - Updating of index finished or was interrupted by
// pre-shutdown.
// -> SHUTDOWN - This could happen only in case of pre-shutdown failure.
UPDATING = 4,
// Index is ready.
// Possible transitions:
// -> UPDATING - Index was found outdated.
// -> SHUTDOWN - Index is shutting down.
READY = 5,
// Index is shutting down.
SHUTDOWN = 6
};
static char const *StateString(EState aState);
void ChangeState(EState aNewState);
void NotifyAsyncGetDiskConsumptionCallbacks();
// Allocates and releases buffer used for reading and writing index.
void AllocBuffer();
void ReleaseBuffer();
// Methods used by CacheIndexEntryAutoManage to keep the iterators up to date.
void AddRecordToIterators(CacheIndexRecord *aRecord);
void RemoveRecordFromIterators(CacheIndexRecord *aRecord);
void ReplaceRecordInIterators(CacheIndexRecord *aOldRecord,
CacheIndexRecord *aNewRecord);
// Memory reporting (private part)
size_t SizeOfExcludingThisInternal(mozilla::MallocSizeOf mallocSizeOf) const;
void ReportHashStats();
static mozilla::StaticRefPtr<CacheIndex> gInstance;
static StaticMutex sLock;
nsCOMPtr<nsIFile> mCacheDirectory;
EState mState;
// Timestamp of time when the index was initialized. We use it to delay
// initial update or build of index.
TimeStamp mStartTime;
// Set to true in PreShutdown(), it is checked on variaous places to prevent
// starting any process (write, update, etc.) during shutdown.
bool mShuttingDown;
// When set to true, update process should start as soon as possible. This
// flag is set whenever we find some inconsistency which would be fixed by
// update process. The flag is checked always when switching to READY state.
// To make sure we start the update process as soon as possible, methods that
// set this flag should also call StartUpdatingIndexIfNeeded() to cover the
// case when we are currently in READY state.
bool mIndexNeedsUpdate;
// Set at the beginning of RemoveAll() which clears the whole index. When
// removing all entries we must stop any pending reading, writing, updating or
// building operation. This flag is checked at various places and it prevents
// we won't start another operation (e.g. canceling reading of the index would
// normally start update or build process)
bool mRemovingAll;
// Whether the index file on disk exists and is valid.
bool mIndexOnDiskIsValid;
// When something goes wrong during updating or building process, we don't
// mark index clean (and also don't write journal) to ensure that update or
// build will be initiated on the next start.
bool mDontMarkIndexClean;
// Timestamp value from index file. It is used during update process to skip
// entries that were last modified before this timestamp.
uint32_t mIndexTimeStamp;
// Timestamp of last time the index was dumped to disk.
// NOTE: The index might not be necessarily dumped at this time. The value
// is used to schedule next dump of the index.
TimeStamp mLastDumpTime;
// Timer of delayed update/build.
nsCOMPtr<nsITimer> mUpdateTimer;
// True when build or update event is posted
bool mUpdateEventPending;
// Helper members used when reading/writing index from/to disk.
// Contains number of entries that should be skipped:
// - in hashtable when writing index because they were already written
// - in index file when reading index because they were already read
uint32_t mSkipEntries;
// Number of entries that should be written to disk. This is number of entries
// in hashtable that are initialized and are not marked as removed when
// writing begins.
uint32_t mProcessEntries;
char *mRWBuf;
uint32_t mRWBufSize;
uint32_t mRWBufPos;
RefPtr<CacheHash> mRWHash;
// True if read or write operation is pending. It is used to ensure that
// mRWBuf is not freed until OnDataRead or OnDataWritten is called.
bool mRWPending;
// Reading of journal succeeded if true.
bool mJournalReadSuccessfully;
// Handle used for writing and reading index file.
RefPtr<CacheFileHandle> mIndexHandle;
// Handle used for reading journal file.
RefPtr<CacheFileHandle> mJournalHandle;
// Used to check the existence of the file during reading process.
RefPtr<CacheFileHandle> mTmpHandle;
RefPtr<FileOpenHelper> mIndexFileOpener;
RefPtr<FileOpenHelper> mJournalFileOpener;
RefPtr<FileOpenHelper> mTmpFileOpener;
// Directory enumerator used when building and updating index.
nsCOMPtr<nsIDirectoryEnumerator> mDirEnumerator;
// Main index hashtable.
nsTHashtable<CacheIndexEntry> mIndex;
// We cannot add, remove or change any entry in mIndex in states READING and
// WRITING. We track all changes in mPendingUpdates during these states.
nsTHashtable<CacheIndexEntryUpdate> mPendingUpdates;
// Contains information statistics for mIndex + mPendingUpdates.
CacheIndexStats mIndexStats;
// When reading journal, we must first parse the whole file and apply the
// changes iff the journal was read successfully. mTmpJournal is used to store
// entries from the journal file. We throw away all these entries if parsing
// of the journal fails or the hash does not match.
nsTHashtable<CacheIndexEntry> mTmpJournal;
// FrecencyArray maintains order of entry records for eviction. Ideally, the
// records would be ordered by frecency all the time, but since this would be
// quite expensive, we allow certain amount of entries to be out of order.
// When the frecency is updated the new value is always bigger than the old
// one. Instead of keeping updated entries at the same position, we move them
// at the end of the array. This protects recently updated entries from
// eviction. The array is sorted once we hit the limit of maximum unsorted
// entries.
class FrecencyArray {
class Iterator {
public:
explicit Iterator(nsTArray<CacheIndexRecord *> *aRecs)
: mRecs(aRecs), mIdx(0) {
while (!Done() && !(*mRecs)[mIdx]) {
mIdx++;
}
}
bool Done() const { return mIdx == mRecs->Length(); }
CacheIndexRecord *Get() const {
MOZ_ASSERT(!Done());
return (*mRecs)[mIdx];
}
void Next() {
MOZ_ASSERT(!Done());
++mIdx;
while (!Done() && !(*mRecs)[mIdx]) {
mIdx++;
}
}
private:
nsTArray<CacheIndexRecord *> *mRecs;
uint32_t mIdx;
};
public:
Iterator Iter() { return Iterator(&mRecs); }
FrecencyArray() : mUnsortedElements(0), mRemovedElements(0) {}
// Methods used by CacheIndexEntryAutoManage to keep the array up to date.
void AppendRecord(CacheIndexRecord *aRecord);
void RemoveRecord(CacheIndexRecord *aRecord);
void ReplaceRecord(CacheIndexRecord *aOldRecord,
CacheIndexRecord *aNewRecord);
void SortIfNeeded();
size_t Length() const { return mRecs.Length() - mRemovedElements; }
void Clear() { mRecs.Clear(); }
private:
friend class CacheIndex;
nsTArray<CacheIndexRecord *> mRecs;
uint32_t mUnsortedElements;
// Instead of removing elements from the array immediately, we null them out
// and the iterator skips them when accessing the array. The null pointers
// are placed at the end during sorting and we strip them out all at once.
// This saves moving a lot of memory in nsTArray::RemoveElementsAt.
uint32_t mRemovedElements;
};
FrecencyArray mFrecencyArray;
nsTArray<CacheIndexIterator *> mIterators;
// This flag is true iff we are between CacheStorageService:Clear() and
// processing all contexts to be evicted. It will make UI to show
// "calculating" instead of any intermediate cache size.
bool mAsyncGetDiskConsumptionBlocked;
class DiskConsumptionObserver : public Runnable {
public:
static DiskConsumptionObserver *Init(
nsICacheStorageConsumptionObserver *aObserver) {
nsWeakPtr observer = do_GetWeakReference(aObserver);
if (!observer) return nullptr;
return new DiskConsumptionObserver(observer);
}
void OnDiskConsumption(int64_t aSize) {
mSize = aSize;
NS_DispatchToMainThread(this);
}
private:
explicit DiskConsumptionObserver(nsWeakPtr const &aWeakObserver)
: Runnable("net::CacheIndex::DiskConsumptionObserver"),
mObserver(aWeakObserver),
mSize(0) {}
virtual ~DiskConsumptionObserver() {
if (mObserver && !NS_IsMainThread()) {
NS_ReleaseOnMainThreadSystemGroup("DiskConsumptionObserver::mObserver",
mObserver.forget());
}
}
NS_IMETHOD Run() override {
MOZ_ASSERT(NS_IsMainThread());
nsCOMPtr<nsICacheStorageConsumptionObserver> observer =
do_QueryReferent(mObserver);
mObserver = nullptr;
if (observer) {
observer->OnNetworkCacheDiskConsumption(mSize);
}
return NS_OK;
}
nsWeakPtr mObserver;
int64_t mSize;
};
// List of async observers that want to get disk consumption information
nsTArray<RefPtr<DiskConsumptionObserver> > mDiskConsumptionObservers;
};
} // namespace net
} // namespace mozilla
#endif