gecko-dev/netwerk/cache2/CacheEntry.cpp

1609 строки
42 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/. */
#include "CacheLog.h"
#include "CacheEntry.h"
#include "CacheStorageService.h"
#include "CacheObserver.h"
#include "CacheFileUtils.h"
#include "CacheIndex.h"
#include "nsIInputStream.h"
#include "nsIOutputStream.h"
#include "nsISeekableStream.h"
#include "nsIURI.h"
#include "nsICacheEntryOpenCallback.h"
#include "nsICacheStorage.h"
#include "nsISerializable.h"
#include "nsIStreamTransportService.h"
#include "nsISizeOf.h"
#include "nsComponentManagerUtils.h"
#include "nsServiceManagerUtils.h"
#include "nsString.h"
#include "nsProxyRelease.h"
#include "nsSerializationHelper.h"
#include "nsThreadUtils.h"
#include "mozilla/Telemetry.h"
#include <math.h>
#include <algorithm>
namespace mozilla {
namespace net {
static uint32_t const ENTRY_WANTED =
nsICacheEntryOpenCallback::ENTRY_WANTED;
static uint32_t const RECHECK_AFTER_WRITE_FINISHED =
nsICacheEntryOpenCallback::RECHECK_AFTER_WRITE_FINISHED;
static uint32_t const ENTRY_NEEDS_REVALIDATION =
nsICacheEntryOpenCallback::ENTRY_NEEDS_REVALIDATION;
static uint32_t const ENTRY_NOT_WANTED =
nsICacheEntryOpenCallback::ENTRY_NOT_WANTED;
NS_IMPL_ISUPPORTS(CacheEntryHandle, nsICacheEntry)
// CacheEntryHandle
CacheEntryHandle::CacheEntryHandle(CacheEntry* aEntry)
: mEntry(aEntry)
{
MOZ_COUNT_CTOR(CacheEntryHandle);
#ifdef DEBUG
if (!mEntry->HandlesCount()) {
// CacheEntry.mHandlesCount must go from zero to one only under
// the service lock. Can access CacheStorageService::Self() w/o a check
// since CacheEntry hrefs it.
CacheStorageService::Self()->Lock().AssertCurrentThreadOwns();
}
#endif
mEntry->AddHandleRef();
LOG(("New CacheEntryHandle %p for entry %p", this, aEntry));
}
CacheEntryHandle::~CacheEntryHandle()
{
mEntry->ReleaseHandleRef();
mEntry->OnHandleClosed(this);
MOZ_COUNT_DTOR(CacheEntryHandle);
}
// CacheEntry::Callback
CacheEntry::Callback::Callback(CacheEntry* aEntry,
nsICacheEntryOpenCallback *aCallback,
bool aReadOnly, bool aCheckOnAnyThread)
: mEntry(aEntry)
, mCallback(aCallback)
, mTargetThread(do_GetCurrentThread())
, mReadOnly(aReadOnly)
, mCheckOnAnyThread(aCheckOnAnyThread)
, mRecheckAfterWrite(false)
, mNotWanted(false)
{
MOZ_COUNT_CTOR(CacheEntry::Callback);
// The counter may go from zero to non-null only under the service lock
// but here we expect it to be already positive.
MOZ_ASSERT(mEntry->HandlesCount());
mEntry->AddHandleRef();
}
CacheEntry::Callback::Callback(CacheEntry::Callback const &aThat)
: mEntry(aThat.mEntry)
, mCallback(aThat.mCallback)
, mTargetThread(aThat.mTargetThread)
, mReadOnly(aThat.mReadOnly)
, mCheckOnAnyThread(aThat.mCheckOnAnyThread)
, mRecheckAfterWrite(aThat.mRecheckAfterWrite)
, mNotWanted(aThat.mNotWanted)
{
MOZ_COUNT_CTOR(CacheEntry::Callback);
// The counter may go from zero to non-null only under the service lock
// but here we expect it to be already positive.
MOZ_ASSERT(mEntry->HandlesCount());
mEntry->AddHandleRef();
}
CacheEntry::Callback::~Callback()
{
ProxyRelease(mCallback, mTargetThread);
mEntry->ReleaseHandleRef();
MOZ_COUNT_DTOR(CacheEntry::Callback);
}
void CacheEntry::Callback::ExchangeEntry(CacheEntry* aEntry)
{
if (mEntry == aEntry)
return;
// The counter may go from zero to non-null only under the service lock
// but here we expect it to be already positive.
MOZ_ASSERT(aEntry->HandlesCount());
aEntry->AddHandleRef();
mEntry->ReleaseHandleRef();
mEntry = aEntry;
}
nsresult CacheEntry::Callback::OnCheckThread(bool *aOnCheckThread) const
{
if (!mCheckOnAnyThread) {
// Check we are on the target
return mTargetThread->IsOnCurrentThread(aOnCheckThread);
}
// We can invoke check anywhere
*aOnCheckThread = true;
return NS_OK;
}
nsresult CacheEntry::Callback::OnAvailThread(bool *aOnAvailThread) const
{
return mTargetThread->IsOnCurrentThread(aOnAvailThread);
}
// CacheEntry
NS_IMPL_ISUPPORTS(CacheEntry,
nsICacheEntry,
nsIRunnable,
CacheFileListener)
CacheEntry::CacheEntry(const nsACString& aStorageID,
nsIURI* aURI,
const nsACString& aEnhanceID,
bool aUseDisk)
: mFrecency(0)
, mSortingExpirationTime(uint32_t(-1))
, mLock("CacheEntry")
, mFileStatus(NS_ERROR_NOT_INITIALIZED)
, mURI(aURI)
, mEnhanceID(aEnhanceID)
, mStorageID(aStorageID)
, mUseDisk(aUseDisk)
, mIsDoomed(false)
, mSecurityInfoLoaded(false)
, mPreventCallbacks(false)
, mHasData(false)
, mState(NOTLOADED)
, mRegistration(NEVERREGISTERED)
, mWriter(nullptr)
, mPredictedDataSize(0)
, mReleaseThread(NS_GetCurrentThread())
{
MOZ_COUNT_CTOR(CacheEntry);
mService = CacheStorageService::Self();
CacheStorageService::Self()->RecordMemoryOnlyEntry(
this, !aUseDisk, true /* overwrite */);
}
CacheEntry::~CacheEntry()
{
ProxyRelease(mURI, mReleaseThread);
LOG(("CacheEntry::~CacheEntry [this=%p]", this));
MOZ_COUNT_DTOR(CacheEntry);
}
#ifdef PR_LOG
char const * CacheEntry::StateString(uint32_t aState)
{
switch (aState) {
case NOTLOADED: return "NOTLOADED";
case LOADING: return "LOADING";
case EMPTY: return "EMPTY";
case WRITING: return "WRITING";
case READY: return "READY";
case REVALIDATING: return "REVALIDATING";
}
return "?";
}
#endif
nsresult CacheEntry::HashingKeyWithStorage(nsACString &aResult)
{
return HashingKey(mStorageID, mEnhanceID, mURI, aResult);
}
nsresult CacheEntry::HashingKey(nsACString &aResult)
{
return HashingKey(EmptyCString(), mEnhanceID, mURI, aResult);
}
// static
nsresult CacheEntry::HashingKey(nsCSubstring const& aStorageID,
nsCSubstring const& aEnhanceID,
nsIURI* aURI,
nsACString &aResult)
{
nsAutoCString spec;
nsresult rv = aURI->GetAsciiSpec(spec);
NS_ENSURE_SUCCESS(rv, rv);
return HashingKey(aStorageID, aEnhanceID, spec, aResult);
}
// static
nsresult CacheEntry::HashingKey(nsCSubstring const& aStorageID,
nsCSubstring const& aEnhanceID,
nsCSubstring const& aURISpec,
nsACString &aResult)
{
/**
* This key is used to salt hash that is a base for disk file name.
* Changing it will cause we will not be able to find files on disk.
*/
aResult.Append(aStorageID);
if (!aEnhanceID.IsEmpty()) {
CacheFileUtils::AppendTagWithValue(aResult, '~', aEnhanceID);
}
// Appending directly
aResult.Append(':');
aResult.Append(aURISpec);
return NS_OK;
}
void CacheEntry::AsyncOpen(nsICacheEntryOpenCallback* aCallback, uint32_t aFlags)
{
LOG(("CacheEntry::AsyncOpen [this=%p, state=%s, flags=%d, callback=%p]",
this, StateString(mState), aFlags, aCallback));
bool readonly = aFlags & nsICacheStorage::OPEN_READONLY;
bool truncate = aFlags & nsICacheStorage::OPEN_TRUNCATE;
bool priority = aFlags & nsICacheStorage::OPEN_PRIORITY;
bool multithread = aFlags & nsICacheStorage::CHECK_MULTITHREADED;
MOZ_ASSERT(!readonly || !truncate, "Bad flags combination");
MOZ_ASSERT(!(truncate && mState > LOADING), "Must not call truncate on already loaded entry");
Callback callback(this, aCallback, readonly, multithread);
mozilla::MutexAutoLock lock(mLock);
RememberCallback(callback);
// Load() opens the lock
if (Load(truncate, priority)) {
// Loading is in progress...
return;
}
InvokeCallbacks();
}
bool CacheEntry::Load(bool aTruncate, bool aPriority)
{
LOG(("CacheEntry::Load [this=%p, trunc=%d]", this, aTruncate));
mLock.AssertCurrentThreadOwns();
if (mState > LOADING) {
LOG((" already loaded"));
return false;
}
if (mState == LOADING) {
LOG((" already loading"));
return true;
}
mState = LOADING;
MOZ_ASSERT(!mFile);
nsresult rv;
nsAutoCString fileKey;
rv = HashingKeyWithStorage(fileKey);
if (!aTruncate && NS_SUCCEEDED(rv)) {
// Check the index right now to know we have or have not the entry
// as soon as possible.
CacheIndex::EntryStatus status;
if (NS_SUCCEEDED(CacheIndex::HasEntry(fileKey, &status)) &&
status == CacheIndex::DOES_NOT_EXIST) {
LOG((" entry doesn't exist according information from the index, truncating"));
aTruncate = true;
}
}
mFile = new CacheFile();
BackgroundOp(Ops::REGISTER);
bool directLoad = aTruncate || !mUseDisk;
if (directLoad)
mFileStatus = NS_OK;
else
mLoadStart = TimeStamp::Now();
{
mozilla::MutexAutoUnlock unlock(mLock);
LOG((" performing load, file=%p", mFile.get()));
if (NS_SUCCEEDED(rv)) {
rv = mFile->Init(fileKey,
aTruncate,
!mUseDisk,
aPriority,
directLoad ? nullptr : this);
}
if (NS_FAILED(rv)) {
mFileStatus = rv;
AsyncDoom(nullptr);
return false;
}
}
if (directLoad) {
// Just fake the load has already been done as "new".
mState = EMPTY;
}
return mState == LOADING;
}
NS_IMETHODIMP CacheEntry::OnFileReady(nsresult aResult, bool aIsNew)
{
LOG(("CacheEntry::OnFileReady [this=%p, rv=0x%08x, new=%d]",
this, aResult, aIsNew));
MOZ_ASSERT(!mLoadStart.IsNull());
if (NS_SUCCEEDED(aResult)) {
if (aIsNew) {
mozilla::Telemetry::AccumulateTimeDelta(
mozilla::Telemetry::NETWORK_CACHE_V2_MISS_TIME_MS,
mLoadStart);
}
else {
mozilla::Telemetry::AccumulateTimeDelta(
mozilla::Telemetry::NETWORK_CACHE_V2_HIT_TIME_MS,
mLoadStart);
}
}
// OnFileReady, that is the only code that can transit from LOADING
// to any follow-on state, can only be invoked ones on an entry,
// thus no need to lock. Until this moment there is no consumer that
// could manipulate the entry state.
mozilla::MutexAutoLock lock(mLock);
MOZ_ASSERT(mState == LOADING);
mState = (aIsNew || NS_FAILED(aResult))
? EMPTY
: READY;
mFileStatus = aResult;
if (mState == READY) {
mHasData = true;
uint32_t frecency;
mFile->GetFrecency(&frecency);
// mFrecency is held in a double to increase computance precision.
// It is ok to persist frecency only as a uint32 with some math involved.
mFrecency = INT2FRECENCY(frecency);
}
InvokeCallbacks();
return NS_OK;
}
NS_IMETHODIMP CacheEntry::OnFileDoomed(nsresult aResult)
{
if (mDoomCallback) {
nsRefPtr<DoomCallbackRunnable> event =
new DoomCallbackRunnable(this, aResult);
NS_DispatchToMainThread(event);
}
return NS_OK;
}
already_AddRefed<CacheEntryHandle> CacheEntry::ReopenTruncated(bool aMemoryOnly,
nsICacheEntryOpenCallback* aCallback)
{
LOG(("CacheEntry::ReopenTruncated [this=%p]", this));
mLock.AssertCurrentThreadOwns();
// Hold callbacks invocation, AddStorageEntry would invoke from doom prematurly
mPreventCallbacks = true;
nsRefPtr<CacheEntryHandle> handle;
nsRefPtr<CacheEntry> newEntry;
{
mozilla::MutexAutoUnlock unlock(mLock);
// The following call dooms this entry (calls DoomAlreadyRemoved on us)
nsresult rv = CacheStorageService::Self()->AddStorageEntry(
GetStorageID(), GetURI(), GetEnhanceID(),
mUseDisk && !aMemoryOnly,
true, // always create
true, // truncate existing (this one)
getter_AddRefs(handle));
if (NS_SUCCEEDED(rv)) {
newEntry = handle->Entry();
LOG((" exchanged entry %p by entry %p, rv=0x%08x", this, newEntry.get(), rv));
newEntry->AsyncOpen(aCallback, nsICacheStorage::OPEN_TRUNCATE);
} else {
LOG((" exchanged of entry %p failed, rv=0x%08x", this, rv));
AsyncDoom(nullptr);
}
}
mPreventCallbacks = false;
if (!newEntry)
return nullptr;
newEntry->TransferCallbacks(*this);
mCallbacks.Clear();
// Must return a new write handle, since the consumer is expected to
// write to this newly recreated entry. The |handle| is only a common
// reference counter and doesn't revert entry state back when write
// fails and also doesn't update the entry frecency. Not updating
// frecency causes entries to not be purged from our memory pools.
nsRefPtr<CacheEntryHandle> writeHandle =
newEntry->NewWriteHandle();
return writeHandle.forget();
}
void CacheEntry::TransferCallbacks(CacheEntry & aFromEntry)
{
mozilla::MutexAutoLock lock(mLock);
LOG(("CacheEntry::TransferCallbacks [entry=%p, from=%p]",
this, &aFromEntry));
if (!mCallbacks.Length())
mCallbacks.SwapElements(aFromEntry.mCallbacks);
else
mCallbacks.AppendElements(aFromEntry.mCallbacks);
uint32_t callbacksLength = mCallbacks.Length();
if (callbacksLength) {
// Carry the entry reference (unfortunatelly, needs to be done manually...)
for (uint32_t i = 0; i < callbacksLength; ++i)
mCallbacks[i].ExchangeEntry(this);
BackgroundOp(Ops::CALLBACKS, true);
}
}
void CacheEntry::RememberCallback(Callback const& aCallback)
{
LOG(("CacheEntry::RememberCallback [this=%p, cb=%p]", this, aCallback.mCallback.get()));
mLock.AssertCurrentThreadOwns();
mCallbacks.AppendElement(aCallback);
}
void CacheEntry::InvokeCallbacksLock()
{
mozilla::MutexAutoLock lock(mLock);
InvokeCallbacks();
}
void CacheEntry::InvokeCallbacks()
{
mLock.AssertCurrentThreadOwns();
LOG(("CacheEntry::InvokeCallbacks BEGIN [this=%p]", this));
// Invoke first all r/w callbacks, then all r/o callbacks.
if (InvokeCallbacks(false))
InvokeCallbacks(true);
LOG(("CacheEntry::InvokeCallbacks END [this=%p]", this));
}
bool CacheEntry::InvokeCallbacks(bool aReadOnly)
{
mLock.AssertCurrentThreadOwns();
uint32_t i = 0;
while (i < mCallbacks.Length()) {
if (mPreventCallbacks) {
LOG((" callbacks prevented!"));
return false;
}
if (!mIsDoomed && (mState == WRITING || mState == REVALIDATING)) {
LOG((" entry is being written/revalidated"));
return false;
}
if (mCallbacks[i].mReadOnly != aReadOnly) {
// Callback is not r/w or r/o, go to another one in line
++i;
continue;
}
bool onCheckThread;
nsresult rv = mCallbacks[i].OnCheckThread(&onCheckThread);
if (NS_SUCCEEDED(rv) && !onCheckThread) {
// Redispatch to the target thread
nsRefPtr<nsRunnableMethod<CacheEntry> > event =
NS_NewRunnableMethod(this, &CacheEntry::InvokeCallbacksLock);
rv = mCallbacks[i].mTargetThread->Dispatch(event, nsIEventTarget::DISPATCH_NORMAL);
if (NS_SUCCEEDED(rv)) {
LOG((" re-dispatching to target thread"));
return false;
}
}
Callback callback = mCallbacks[i];
mCallbacks.RemoveElementAt(i);
if (NS_SUCCEEDED(rv) && !InvokeCallback(callback)) {
// Callback didn't fire, put it back and go to another one in line.
// Only reason InvokeCallback returns false is that onCacheEntryCheck
// returns RECHECK_AFTER_WRITE_FINISHED. If we would stop the loop, other
// readers or potential writers would be unnecessarily kept from being
// invoked.
mCallbacks.InsertElementAt(i, callback);
++i;
}
}
return true;
}
bool CacheEntry::InvokeCallback(Callback & aCallback)
{
LOG(("CacheEntry::InvokeCallback [this=%p, state=%s, cb=%p]",
this, StateString(mState), aCallback.mCallback.get()));
mLock.AssertCurrentThreadOwns();
// When this entry is doomed we want to notify the callback any time
if (!mIsDoomed) {
// When we are here, the entry must be loaded from disk
MOZ_ASSERT(mState > LOADING);
if (mState == WRITING || mState == REVALIDATING) {
// Prevent invoking other callbacks since one of them is now writing
// or revalidating this entry. No consumers should get this entry
// until metadata are filled with values downloaded from the server
// or the entry revalidated and output stream has been opened.
LOG((" entry is being written/revalidated, callback bypassed"));
return false;
}
// mRecheckAfterWrite flag already set means the callback has already passed
// the onCacheEntryCheck call. Until the current write is not finished this
// callback will be bypassed.
if (!aCallback.mRecheckAfterWrite) {
if (!aCallback.mReadOnly) {
if (mState == EMPTY) {
// Advance to writing state, we expect to invoke the callback and let
// it fill content of this entry. Must set and check the state here
// to prevent more then one
mState = WRITING;
LOG((" advancing to WRITING state"));
}
if (!aCallback.mCallback) {
// We can be given no callback only in case of recreate, it is ok
// to advance to WRITING state since the caller of recreate is expected
// to write this entry now.
return true;
}
}
if (mState == READY) {
// Metadata present, validate the entry
uint32_t checkResult;
{
// mayhemer: TODO check and solve any potential races of concurent OnCacheEntryCheck
mozilla::MutexAutoUnlock unlock(mLock);
nsresult rv = aCallback.mCallback->OnCacheEntryCheck(
this, nullptr, &checkResult);
LOG((" OnCacheEntryCheck: rv=0x%08x, result=%d", rv, checkResult));
if (NS_FAILED(rv))
checkResult = ENTRY_NOT_WANTED;
}
switch (checkResult) {
case ENTRY_WANTED:
// Nothing more to do here, the consumer is responsible to handle
// the result of OnCacheEntryCheck it self.
// Proceed to callback...
break;
case RECHECK_AFTER_WRITE_FINISHED:
LOG((" consumer will check on the entry again after write is done"));
// The consumer wants the entry to complete first.
aCallback.mRecheckAfterWrite = true;
break;
case ENTRY_NEEDS_REVALIDATION:
LOG((" will be holding callbacks until entry is revalidated"));
// State is READY now and from that state entry cannot transit to any other
// state then REVALIDATING for which cocurrency is not an issue. Potentially
// no need to lock here.
mState = REVALIDATING;
break;
case ENTRY_NOT_WANTED:
LOG((" consumer not interested in the entry"));
// Do not give this entry to the consumer, it is not interested in us.
aCallback.mNotWanted = true;
break;
}
}
}
}
if (aCallback.mCallback) {
if (!mIsDoomed && aCallback.mRecheckAfterWrite) {
// If we don't have data and the callback wants a complete entry,
// don't invoke now.
bool bypass = !mHasData;
if (!bypass) {
int64_t _unused;
bypass = !mFile->DataSize(&_unused);
}
if (bypass) {
LOG((" bypassing, entry data still being written"));
return false;
}
// Entry is complete now, do the check+avail call again
aCallback.mRecheckAfterWrite = false;
return InvokeCallback(aCallback);
}
mozilla::MutexAutoUnlock unlock(mLock);
InvokeAvailableCallback(aCallback);
}
return true;
}
void CacheEntry::InvokeAvailableCallback(Callback const & aCallback)
{
LOG(("CacheEntry::InvokeAvailableCallback [this=%p, state=%s, cb=%p, r/o=%d, n/w=%d]",
this, StateString(mState), aCallback.mCallback.get(), aCallback.mReadOnly, aCallback.mNotWanted));
nsresult rv;
uint32_t const state = mState;
// When we are here, the entry must be loaded from disk
MOZ_ASSERT(state > LOADING || mIsDoomed);
bool onAvailThread;
rv = aCallback.OnAvailThread(&onAvailThread);
if (NS_FAILED(rv)) {
LOG((" target thread dead?"));
return;
}
if (!onAvailThread) {
// Dispatch to the right thread
nsRefPtr<AvailableCallbackRunnable> event =
new AvailableCallbackRunnable(this, aCallback);
rv = aCallback.mTargetThread->Dispatch(event, nsIEventTarget::DISPATCH_NORMAL);
LOG((" redispatched, (rv = 0x%08x)", rv));
return;
}
if (mIsDoomed || aCallback.mNotWanted) {
LOG((" doomed or not wanted, notifying OCEA with NS_ERROR_CACHE_KEY_NOT_FOUND"));
aCallback.mCallback->OnCacheEntryAvailable(
nullptr, false, nullptr, NS_ERROR_CACHE_KEY_NOT_FOUND);
return;
}
if (state == READY) {
LOG((" ready/has-meta, notifying OCEA with entry and NS_OK"));
{
mozilla::MutexAutoLock lock(mLock);
BackgroundOp(Ops::FRECENCYUPDATE);
}
nsRefPtr<CacheEntryHandle> handle = NewHandle();
aCallback.mCallback->OnCacheEntryAvailable(
handle, false, nullptr, NS_OK);
return;
}
if (aCallback.mReadOnly) {
LOG((" r/o and not ready, notifying OCEA with NS_ERROR_CACHE_KEY_NOT_FOUND"));
aCallback.mCallback->OnCacheEntryAvailable(
nullptr, false, nullptr, NS_ERROR_CACHE_KEY_NOT_FOUND);
return;
}
// This is a new or potentially non-valid entry and needs to be fetched first.
// The CacheEntryHandle blocks other consumers until the channel
// either releases the entry or marks metadata as filled or whole entry valid,
// i.e. until MetaDataReady() or SetValid() on the entry is called respectively.
// Consumer will be responsible to fill or validate the entry metadata and data.
nsRefPtr<CacheEntryHandle> handle = NewWriteHandle();
rv = aCallback.mCallback->OnCacheEntryAvailable(
handle, state == WRITING, nullptr, NS_OK);
if (NS_FAILED(rv)) {
LOG((" writing/revalidating failed (0x%08x)", rv));
// Consumer given a new entry failed to take care of the entry.
OnHandleClosed(handle);
return;
}
LOG((" writing/revalidating"));
}
CacheEntryHandle* CacheEntry::NewHandle()
{
return new CacheEntryHandle(this);
}
CacheEntryHandle* CacheEntry::NewWriteHandle()
{
mozilla::MutexAutoLock lock(mLock);
BackgroundOp(Ops::FRECENCYUPDATE);
return (mWriter = NewHandle());
}
void CacheEntry::OnHandleClosed(CacheEntryHandle const* aHandle)
{
LOG(("CacheEntry::OnHandleClosed [this=%p, state=%s, handle=%p]", this, StateString(mState), aHandle));
nsCOMPtr<nsIOutputStream> outputStream;
{
mozilla::MutexAutoLock lock(mLock);
if (mWriter != aHandle) {
LOG((" not the writer"));
return;
}
if (mOutputStream) {
// No one took our internal output stream, so there are no data
// and output stream has to be open symultaneously with input stream
// on this entry again.
mHasData = false;
}
outputStream.swap(mOutputStream);
mWriter = nullptr;
if (mState == WRITING) {
LOG((" reverting to state EMPTY - write failed"));
mState = EMPTY;
}
else if (mState == REVALIDATING) {
LOG((" reverting to state READY - reval failed"));
mState = READY;
}
InvokeCallbacks();
}
if (outputStream) {
LOG((" abandoning phantom output stream"));
outputStream->Close();
}
}
void CacheEntry::OnOutputClosed()
{
// Called when the file's output stream is closed. Invoke any callbacks
// waiting for complete entry.
mozilla::MutexAutoLock lock(mLock);
InvokeCallbacks();
}
bool CacheEntry::IsUsingDiskLocked() const
{
CacheStorageService::Self()->Lock().AssertCurrentThreadOwns();
return IsUsingDisk();
}
bool CacheEntry::SetUsingDisk(bool aUsingDisk)
{
// Called by the service when this entry is reopen to reflect
// demanded storage target.
if (mState >= READY) {
// Don't modify after this entry has been filled.
return false;
}
CacheStorageService::Self()->Lock().AssertCurrentThreadOwns();
bool changed = mUseDisk != aUsingDisk;
mUseDisk = aUsingDisk;
return changed;
}
bool CacheEntry::IsReferenced() const
{
CacheStorageService::Self()->Lock().AssertCurrentThreadOwns();
// Increasing this counter from 0 to non-null and this check both happen only
// under the service lock.
return mHandlesCount > 0;
}
bool CacheEntry::IsFileDoomed()
{
if (NS_SUCCEEDED(mFileStatus)) {
return mFile->IsDoomed();
}
return false;
}
uint32_t CacheEntry::GetMetadataMemoryConsumption()
{
NS_ENSURE_SUCCESS(mFileStatus, 0);
uint32_t size;
if (NS_FAILED(mFile->ElementsSize(&size)))
return 0;
return size;
}
// nsICacheEntry
NS_IMETHODIMP CacheEntry::GetPersistent(bool *aPersistToDisk)
{
// No need to sync when only reading.
// When consumer needs to be consistent with state of the memory storage entries
// table, then let it use GetUseDisk getter that must be called under the service lock.
*aPersistToDisk = mUseDisk;
return NS_OK;
}
NS_IMETHODIMP CacheEntry::GetKey(nsACString & aKey)
{
return mURI->GetAsciiSpec(aKey);
}
NS_IMETHODIMP CacheEntry::GetFetchCount(int32_t *aFetchCount)
{
NS_ENSURE_SUCCESS(mFileStatus, NS_ERROR_NOT_AVAILABLE);
return mFile->GetFetchCount(reinterpret_cast<uint32_t*>(aFetchCount));
}
NS_IMETHODIMP CacheEntry::GetLastFetched(uint32_t *aLastFetched)
{
NS_ENSURE_SUCCESS(mFileStatus, NS_ERROR_NOT_AVAILABLE);
return mFile->GetLastFetched(aLastFetched);
}
NS_IMETHODIMP CacheEntry::GetLastModified(uint32_t *aLastModified)
{
NS_ENSURE_SUCCESS(mFileStatus, NS_ERROR_NOT_AVAILABLE);
return mFile->GetLastModified(aLastModified);
}
NS_IMETHODIMP CacheEntry::GetExpirationTime(uint32_t *aExpirationTime)
{
NS_ENSURE_SUCCESS(mFileStatus, NS_ERROR_NOT_AVAILABLE);
return mFile->GetExpirationTime(aExpirationTime);
}
NS_IMETHODIMP CacheEntry::SetExpirationTime(uint32_t aExpirationTime)
{
NS_ENSURE_SUCCESS(mFileStatus, NS_ERROR_NOT_AVAILABLE);
nsresult rv = mFile->SetExpirationTime(aExpirationTime);
NS_ENSURE_SUCCESS(rv, rv);
// Aligned assignment, thus atomic.
mSortingExpirationTime = aExpirationTime;
return NS_OK;
}
NS_IMETHODIMP CacheEntry::OpenInputStream(int64_t offset, nsIInputStream * *_retval)
{
LOG(("CacheEntry::OpenInputStream [this=%p]", this));
NS_ENSURE_SUCCESS(mFileStatus, NS_ERROR_NOT_AVAILABLE);
nsresult rv;
nsCOMPtr<nsIInputStream> stream;
rv = mFile->OpenInputStream(getter_AddRefs(stream));
NS_ENSURE_SUCCESS(rv, rv);
nsCOMPtr<nsISeekableStream> seekable =
do_QueryInterface(stream, &rv);
NS_ENSURE_SUCCESS(rv, rv);
rv = seekable->Seek(nsISeekableStream::NS_SEEK_SET, offset);
NS_ENSURE_SUCCESS(rv, rv);
mozilla::MutexAutoLock lock(mLock);
if (!mHasData) {
// So far output stream on this new entry not opened, do it now.
LOG((" creating phantom output stream"));
rv = OpenOutputStreamInternal(0, getter_AddRefs(mOutputStream));
NS_ENSURE_SUCCESS(rv, rv);
}
stream.forget(_retval);
return NS_OK;
}
NS_IMETHODIMP CacheEntry::OpenOutputStream(int64_t offset, nsIOutputStream * *_retval)
{
LOG(("CacheEntry::OpenOutputStream [this=%p]", this));
nsresult rv;
mozilla::MutexAutoLock lock(mLock);
MOZ_ASSERT(mState > EMPTY);
if (mOutputStream && !mIsDoomed) {
LOG((" giving phantom output stream"));
mOutputStream.forget(_retval);
}
else {
rv = OpenOutputStreamInternal(offset, _retval);
if (NS_FAILED(rv)) return rv;
}
// Entry considered ready when writer opens output stream.
if (mState < READY)
mState = READY;
// Invoke any pending readers now.
InvokeCallbacks();
return NS_OK;
}
nsresult CacheEntry::OpenOutputStreamInternal(int64_t offset, nsIOutputStream * *_retval)
{
LOG(("CacheEntry::OpenOutputStreamInternal [this=%p]", this));
NS_ENSURE_SUCCESS(mFileStatus, NS_ERROR_NOT_AVAILABLE);
mLock.AssertCurrentThreadOwns();
if (mIsDoomed) {
LOG((" doomed..."));
return NS_ERROR_NOT_AVAILABLE;
}
MOZ_ASSERT(mState > LOADING);
nsresult rv;
// No need to sync on mUseDisk here, we don't need to be consistent
// with content of the memory storage entries hash table.
if (!mUseDisk) {
rv = mFile->SetMemoryOnly();
NS_ENSURE_SUCCESS(rv, rv);
}
nsRefPtr<CacheOutputCloseListener> listener =
new CacheOutputCloseListener(this);
nsCOMPtr<nsIOutputStream> stream;
rv = mFile->OpenOutputStream(listener, getter_AddRefs(stream));
NS_ENSURE_SUCCESS(rv, rv);
nsCOMPtr<nsISeekableStream> seekable =
do_QueryInterface(stream, &rv);
NS_ENSURE_SUCCESS(rv, rv);
rv = seekable->Seek(nsISeekableStream::NS_SEEK_SET, offset);
NS_ENSURE_SUCCESS(rv, rv);
// Prevent opening output stream again.
mHasData = true;
stream.swap(*_retval);
return NS_OK;
}
NS_IMETHODIMP CacheEntry::GetPredictedDataSize(int64_t *aPredictedDataSize)
{
*aPredictedDataSize = mPredictedDataSize;
return NS_OK;
}
NS_IMETHODIMP CacheEntry::SetPredictedDataSize(int64_t aPredictedDataSize)
{
mPredictedDataSize = aPredictedDataSize;
if (CacheObserver::EntryIsTooBig(mPredictedDataSize, mUseDisk)) {
LOG(("CacheEntry::SetPredictedDataSize [this=%p] too big, dooming", this));
AsyncDoom(nullptr);
return NS_ERROR_FILE_TOO_BIG;
}
return NS_OK;
}
NS_IMETHODIMP CacheEntry::GetSecurityInfo(nsISupports * *aSecurityInfo)
{
{
mozilla::MutexAutoLock lock(mLock);
if (mSecurityInfoLoaded) {
NS_IF_ADDREF(*aSecurityInfo = mSecurityInfo);
return NS_OK;
}
}
NS_ENSURE_SUCCESS(mFileStatus, NS_ERROR_NOT_AVAILABLE);
nsXPIDLCString info;
nsCOMPtr<nsISupports> secInfo;
nsresult rv;
rv = mFile->GetElement("security-info", getter_Copies(info));
NS_ENSURE_SUCCESS(rv, rv);
if (info) {
rv = NS_DeserializeObject(info, getter_AddRefs(secInfo));
NS_ENSURE_SUCCESS(rv, rv);
}
{
mozilla::MutexAutoLock lock(mLock);
mSecurityInfo.swap(secInfo);
mSecurityInfoLoaded = true;
NS_IF_ADDREF(*aSecurityInfo = mSecurityInfo);
}
return NS_OK;
}
NS_IMETHODIMP CacheEntry::SetSecurityInfo(nsISupports *aSecurityInfo)
{
nsresult rv;
NS_ENSURE_SUCCESS(mFileStatus, mFileStatus);
{
mozilla::MutexAutoLock lock(mLock);
mSecurityInfo = aSecurityInfo;
mSecurityInfoLoaded = true;
}
nsCOMPtr<nsISerializable> serializable =
do_QueryInterface(aSecurityInfo);
if (aSecurityInfo && !serializable)
return NS_ERROR_UNEXPECTED;
nsCString info;
if (serializable) {
rv = NS_SerializeToString(serializable, info);
NS_ENSURE_SUCCESS(rv, rv);
}
rv = mFile->SetElement("security-info", info.Length() ? info.get() : nullptr);
NS_ENSURE_SUCCESS(rv, rv);
return NS_OK;
}
NS_IMETHODIMP CacheEntry::GetStorageDataSize(uint32_t *aStorageDataSize)
{
NS_ENSURE_ARG(aStorageDataSize);
int64_t dataSize;
nsresult rv = GetDataSize(&dataSize);
if (NS_FAILED(rv))
return rv;
*aStorageDataSize = (uint32_t)std::min(int64_t(uint32_t(-1)), dataSize);
return NS_OK;
}
NS_IMETHODIMP CacheEntry::AsyncDoom(nsICacheEntryDoomCallback *aCallback)
{
LOG(("CacheEntry::AsyncDoom [this=%p]", this));
{
mozilla::MutexAutoLock lock(mLock);
if (mIsDoomed || mDoomCallback)
return NS_ERROR_IN_PROGRESS; // to aggregate have DOOMING state
mIsDoomed = true;
mDoomCallback = aCallback;
}
// This immediately removes the entry from the master hashtable and also
// immediately dooms the file. This way we make sure that any consumer
// after this point asking for the same entry won't get
// a) this entry
// b) a new entry with the same file
PurgeAndDoom();
return NS_OK;
}
NS_IMETHODIMP CacheEntry::GetMetaDataElement(const char * aKey, char * *aRetval)
{
NS_ENSURE_SUCCESS(mFileStatus, NS_ERROR_NOT_AVAILABLE);
return mFile->GetElement(aKey, aRetval);
}
NS_IMETHODIMP CacheEntry::SetMetaDataElement(const char * aKey, const char * aValue)
{
NS_ENSURE_SUCCESS(mFileStatus, NS_ERROR_NOT_AVAILABLE);
return mFile->SetElement(aKey, aValue);
}
NS_IMETHODIMP CacheEntry::VisitMetaData(nsICacheEntryMetaDataVisitor *aVisitor)
{
NS_ENSURE_SUCCESS(mFileStatus, NS_ERROR_NOT_AVAILABLE);
return mFile->VisitMetaData(aVisitor);
}
NS_IMETHODIMP CacheEntry::MetaDataReady()
{
mozilla::MutexAutoLock lock(mLock);
LOG(("CacheEntry::MetaDataReady [this=%p, state=%s]", this, StateString(mState)));
MOZ_ASSERT(mState > EMPTY);
if (mState == WRITING)
mState = READY;
InvokeCallbacks();
return NS_OK;
}
NS_IMETHODIMP CacheEntry::SetValid()
{
LOG(("CacheEntry::SetValid [this=%p, state=%s]", this, StateString(mState)));
nsCOMPtr<nsIOutputStream> outputStream;
{
mozilla::MutexAutoLock lock(mLock);
MOZ_ASSERT(mState > EMPTY);
mState = READY;
mHasData = true;
InvokeCallbacks();
outputStream.swap(mOutputStream);
}
if (outputStream) {
LOG((" abandoning phantom output stream"));
outputStream->Close();
}
return NS_OK;
}
NS_IMETHODIMP CacheEntry::Recreate(bool aMemoryOnly,
nsICacheEntry **_retval)
{
LOG(("CacheEntry::Recreate [this=%p, state=%s]", this, StateString(mState)));
mozilla::MutexAutoLock lock(mLock);
nsRefPtr<CacheEntryHandle> handle = ReopenTruncated(aMemoryOnly, nullptr);
if (handle) {
handle.forget(_retval);
return NS_OK;
}
BackgroundOp(Ops::CALLBACKS, true);
return NS_OK;
}
NS_IMETHODIMP CacheEntry::GetDataSize(int64_t *aDataSize)
{
LOG(("CacheEntry::GetDataSize [this=%p]", this));
*aDataSize = 0;
{
mozilla::MutexAutoLock lock(mLock);
if (!mHasData) {
LOG((" write in progress (no data)"));
return NS_ERROR_IN_PROGRESS;
}
}
NS_ENSURE_SUCCESS(mFileStatus, mFileStatus);
// mayhemer: TODO Problem with compression?
if (!mFile->DataSize(aDataSize)) {
LOG((" write in progress (stream active)"));
return NS_ERROR_IN_PROGRESS;
}
LOG((" size=%lld", *aDataSize));
return NS_OK;
}
NS_IMETHODIMP CacheEntry::MarkValid()
{
// NOT IMPLEMENTED ACTUALLY
return NS_OK;
}
NS_IMETHODIMP CacheEntry::MaybeMarkValid()
{
// NOT IMPLEMENTED ACTUALLY
return NS_OK;
}
NS_IMETHODIMP CacheEntry::HasWriteAccess(bool aWriteAllowed, bool *aWriteAccess)
{
*aWriteAccess = aWriteAllowed;
return NS_OK;
}
NS_IMETHODIMP CacheEntry::Close()
{
// NOT IMPLEMENTED ACTUALLY
return NS_OK;
}
// nsIRunnable
NS_IMETHODIMP CacheEntry::Run()
{
MOZ_ASSERT(CacheStorageService::IsOnManagementThread());
mozilla::MutexAutoLock lock(mLock);
BackgroundOp(mBackgroundOperations.Grab());
return NS_OK;
}
// Management methods
double CacheEntry::GetFrecency() const
{
MOZ_ASSERT(CacheStorageService::IsOnManagementThread());
return mFrecency;
}
uint32_t CacheEntry::GetExpirationTime() const
{
MOZ_ASSERT(CacheStorageService::IsOnManagementThread());
return mSortingExpirationTime;
}
bool CacheEntry::IsRegistered() const
{
MOZ_ASSERT(CacheStorageService::IsOnManagementThread());
return mRegistration == REGISTERED;
}
bool CacheEntry::CanRegister() const
{
MOZ_ASSERT(CacheStorageService::IsOnManagementThread());
return mRegistration == NEVERREGISTERED;
}
void CacheEntry::SetRegistered(bool aRegistered)
{
MOZ_ASSERT(CacheStorageService::IsOnManagementThread());
if (aRegistered) {
MOZ_ASSERT(mRegistration == NEVERREGISTERED);
mRegistration = REGISTERED;
}
else {
MOZ_ASSERT(mRegistration == REGISTERED);
mRegistration = DEREGISTERED;
}
}
bool CacheEntry::Purge(uint32_t aWhat)
{
LOG(("CacheEntry::Purge [this=%p, what=%d]", this, aWhat));
MOZ_ASSERT(CacheStorageService::IsOnManagementThread());
switch (aWhat) {
case PURGE_DATA_ONLY_DISK_BACKED:
case PURGE_WHOLE_ONLY_DISK_BACKED:
// This is an in-memory only entry, don't purge it
if (!mUseDisk) {
LOG((" not using disk"));
return false;
}
}
if (mState == WRITING || mState == LOADING || mFrecency == 0) {
// In-progress (write or load) entries should (at least for consistency and from
// the logical point of view) stay in memory.
// Zero-frecency entries are those which have never been given to any consumer, those
// are actually very fresh and should not go just because frecency had not been set
// so far.
LOG((" state=%s, frecency=%1.10f", StateString(mState), mFrecency));
return false;
}
if (NS_SUCCEEDED(mFileStatus) && mFile->IsWriteInProgress()) {
// The file is used when there are open streams or chunks/metadata still waiting for
// write. In this case, this entry cannot be purged, otherwise reopenned entry
// would may not even find the data on disk - CacheFile is not shared and cannot be
// left orphan when its job is not done, hence keep the whole entry.
LOG((" file still under use"));
return false;
}
switch (aWhat) {
case PURGE_WHOLE_ONLY_DISK_BACKED:
case PURGE_WHOLE:
{
if (!CacheStorageService::Self()->RemoveEntry(this, true)) {
LOG((" not purging, still referenced"));
return false;
}
CacheStorageService::Self()->UnregisterEntry(this);
// Entry removed it self from control arrays, return true
return true;
}
case PURGE_DATA_ONLY_DISK_BACKED:
{
NS_ENSURE_SUCCESS(mFileStatus, false);
mFile->ThrowMemoryCachedData();
// Entry has been left in control arrays, return false (not purged)
return false;
}
}
LOG((" ?"));
return false;
}
void CacheEntry::PurgeAndDoom()
{
LOG(("CacheEntry::PurgeAndDoom [this=%p]", this));
CacheStorageService::Self()->RemoveEntry(this);
DoomAlreadyRemoved();
}
void CacheEntry::DoomAlreadyRemoved()
{
LOG(("CacheEntry::DoomAlreadyRemoved [this=%p]", this));
mozilla::MutexAutoLock lock(mLock);
mIsDoomed = true;
// This schedules dooming of the file, dooming is ensured to happen
// sooner than demand to open the same file made after this point
// so that we don't get this file for any newer opened entry(s).
DoomFile();
// Must force post here since may be indirectly called from
// InvokeCallbacks of this entry and we don't want reentrancy here.
BackgroundOp(Ops::CALLBACKS, true);
// Process immediately when on the management thread.
BackgroundOp(Ops::UNREGISTER);
}
void CacheEntry::DoomFile()
{
nsresult rv = NS_ERROR_NOT_AVAILABLE;
if (NS_SUCCEEDED(mFileStatus)) {
// Always calls the callback asynchronously.
rv = mFile->Doom(mDoomCallback ? this : nullptr);
if (NS_SUCCEEDED(rv)) {
LOG((" file doomed"));
return;
}
if (NS_ERROR_FILE_NOT_FOUND == rv) {
// File is set to be just memory-only, notify the callbacks
// and pretend dooming has succeeded. From point of view of
// the entry it actually did - the data is gone and cannot be
// reused.
rv = NS_OK;
}
}
// Always posts to the main thread.
OnFileDoomed(rv);
}
void CacheEntry::BackgroundOp(uint32_t aOperations, bool aForceAsync)
{
mLock.AssertCurrentThreadOwns();
if (!CacheStorageService::IsOnManagementThread() || aForceAsync) {
if (mBackgroundOperations.Set(aOperations))
CacheStorageService::Self()->Dispatch(this);
LOG(("CacheEntry::BackgroundOp this=%p dipatch of %x", this, aOperations));
return;
}
mozilla::MutexAutoUnlock unlock(mLock);
MOZ_ASSERT(CacheStorageService::IsOnManagementThread());
if (aOperations & Ops::FRECENCYUPDATE) {
#ifndef M_LN2
#define M_LN2 0.69314718055994530942
#endif
// Half-life is dynamic, in seconds.
static double half_life = CacheObserver::HalfLifeSeconds();
// Must convert from seconds to milliseconds since PR_Now() gives usecs.
static double const decay = (M_LN2 / half_life) / static_cast<double>(PR_USEC_PER_SEC);
double now_decay = static_cast<double>(PR_Now()) * decay;
if (mFrecency == 0) {
mFrecency = now_decay;
}
else {
// TODO: when C++11 enabled, use std::log1p(n) which is equal to log(n + 1) but
// more precise.
mFrecency = log(exp(mFrecency - now_decay) + 1) + now_decay;
}
LOG(("CacheEntry FRECENCYUPDATE [this=%p, frecency=%1.10f]", this, mFrecency));
// Because CacheFile::Set*() are not thread-safe to use (uses WeakReference that
// is not thread-safe) we must post to the main thread...
nsRefPtr<nsRunnableMethod<CacheEntry> > event =
NS_NewRunnableMethod(this, &CacheEntry::StoreFrecency);
NS_DispatchToMainThread(event);
}
if (aOperations & Ops::REGISTER) {
LOG(("CacheEntry REGISTER [this=%p]", this));
CacheStorageService::Self()->RegisterEntry(this);
}
if (aOperations & Ops::UNREGISTER) {
LOG(("CacheEntry UNREGISTER [this=%p]", this));
CacheStorageService::Self()->UnregisterEntry(this);
}
if (aOperations & Ops::CALLBACKS) {
LOG(("CacheEntry CALLBACKS (invoke) [this=%p]", this));
mozilla::MutexAutoLock lock(mLock);
InvokeCallbacks();
}
}
void CacheEntry::StoreFrecency()
{
// No need for thread safety over mFrecency, it will be rewriten
// correctly on following invocation if broken by concurrency.
MOZ_ASSERT(NS_IsMainThread());
mFile->SetFrecency(FRECENCY2INT(mFrecency));
}
// CacheOutputCloseListener
CacheOutputCloseListener::CacheOutputCloseListener(CacheEntry* aEntry)
: mEntry(aEntry)
{
MOZ_COUNT_CTOR(CacheOutputCloseListener);
}
CacheOutputCloseListener::~CacheOutputCloseListener()
{
MOZ_COUNT_DTOR(CacheOutputCloseListener);
}
void CacheOutputCloseListener::OnOutputClosed()
{
// We need this class and to redispatch since this callback is invoked
// under the file's lock and to do the job we need to enter the entry's
// lock too. That would lead to potential deadlocks.
NS_DispatchToCurrentThread(this);
}
NS_IMETHODIMP CacheOutputCloseListener::Run()
{
mEntry->OnOutputClosed();
return NS_OK;
}
// Memory reporting
size_t CacheEntry::SizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf) const
{
size_t n = 0;
nsCOMPtr<nsISizeOf> sizeOf;
n += mCallbacks.SizeOfExcludingThis(mallocSizeOf);
if (mFile) {
n += mFile->SizeOfIncludingThis(mallocSizeOf);
}
sizeOf = do_QueryInterface(mURI);
if (sizeOf) {
n += sizeOf->SizeOfIncludingThis(mallocSizeOf);
}
n += mEnhanceID.SizeOfExcludingThisIfUnshared(mallocSizeOf);
n += mStorageID.SizeOfExcludingThisIfUnshared(mallocSizeOf);
// mDoomCallback is an arbitrary class that is probably reported elsewhere.
// mOutputStream is reported in mFile.
// mWriter is one of many handles we create, but (intentionally) not keep
// any reference to, so those unfortunatelly cannot be reported. Handles are
// small, though.
// mSecurityInfo doesn't impl nsISizeOf.
return n;
}
size_t CacheEntry::SizeOfIncludingThis(mozilla::MallocSizeOf mallocSizeOf) const
{
return mallocSizeOf(this) + SizeOfExcludingThis(mallocSizeOf);
}
} // net
} // mozilla