/* 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 #include 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) , mUseCount(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) const { return HashingKey(mStorageID, mEnhanceID, mURI, aResult); } nsresult CacheEntry::HashingKey(nsACString &aResult) const { 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 bypassIfBusy = aFlags & nsICacheStorage::OPEN_BYPASS_IF_BUSY; 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); if (!Open(callback, truncate, priority, bypassIfBusy)) { // We get here when the callback wants to bypass cache when it's busy. LOG((" writing or revalidating, callback wants to bypass cache")); callback.mNotWanted = true; InvokeAvailableCallback(callback); } } bool CacheEntry::Open(Callback & aCallback, bool aTruncate, bool aPriority, bool aBypassIfBusy) { mozilla::MutexAutoLock lock(mLock); // Check state under the lock if (aBypassIfBusy && (mState == WRITING || mState == REVALIDATING)) { return false; } RememberCallback(aCallback); // Load() opens the lock if (Load(aTruncate, aPriority)) { // Loading is in progress... return true; } InvokeCallbacks(); return true; } 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); // Check the index under two conditions for two states and take appropriate action: // 1. When this is a disk entry and not told to truncate, check there is a disk file. // If not, set the 'truncate' flag to true so that this entry will open instantly // as a new one. // 2. When this is a memory-only entry, check there is a disk file. // If there is or could be, doom that file. if ((!aTruncate || !mUseDisk) && 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))) { switch (status) { case CacheIndex::DOES_NOT_EXIST: LOG((" entry doesn't exist according information from the index, truncating")); aTruncate = true; break; case CacheIndex::EXISTS: case CacheIndex::DO_NOT_KNOW: if (!mUseDisk) { LOG((" entry open as memory-only, but there is (status=%d) a file, dooming it", status)); CacheFileIOManager::DoomFileByKey(fileKey, nullptr); } break; } } } mFile = new CacheFile(); BackgroundOp(Ops::REGISTER); bool directLoad = aTruncate || !mUseDisk; if (directLoad) { mFileStatus = NS_OK; // mLoadStart will be used to calculate telemetry of life-time of this entry. // Low resulution is then enough. mLoadStart = TimeStamp::NowLoRes(); } 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 event = new DoomCallbackRunnable(this, aResult); NS_DispatchToMainThread(event); } return NS_OK; } already_AddRefed 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 handle; nsRefPtr 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 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 & aCallback) { mLock.AssertCurrentThreadOwns(); LOG(("CacheEntry::RememberCallback [this=%p, cb=%p, state=%s]", this, aCallback.mCallback.get(), StateString(mState))); 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 > 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 && NS_SUCCEEDED(mFileStatus)) { 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 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 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 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 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; } if (mState == READY && !mHasData) { // We may get to this state when following steps happen: // 1. a new entry is given to a consumer // 2. the consumer calls MetaDataReady(), we transit to READY // 3. abandons the entry w/o opening the output stream, mHasData left false // // In this case any following consumer will get a ready entry (with metadata) // but in state like the entry data write was still happening (was in progress) // and will indefinitely wait for the entry data or even the entry itself when // RECHECK_AFTER_WRITE is returned from onCacheEntryCheck. LOG((" we are in READY state, pretend we have data regardless it" " has actully been never touched")); mHasData = true; } 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::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(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 stream; rv = mFile->OpenInputStream(getter_AddRefs(stream)); NS_ENSURE_SUCCESS(rv, rv); nsCOMPtr 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 listener = new CacheOutputCloseListener(this); nsCOMPtr stream; rv = mFile->OpenOutputStream(listener, getter_AddRefs(stream)); NS_ENSURE_SUCCESS(rv, rv); nsCOMPtr 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 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 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 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 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) { ++mUseCount; #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(PR_USEC_PER_SEC); double now_decay = static_cast(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 > 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); } } // unlock if (aOperations & Ops::CALLBACKS) { LOG(("CacheEntry CALLBACKS (invoke) [this=%p]", this)); 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()); if (NS_SUCCEEDED(mFileStatus)) { 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 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