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Diffstat (limited to 'netwerk/cache2/CacheIndex.h')
| -rw-r--r-- | netwerk/cache2/CacheIndex.h | 1153 |
1 files changed, 1153 insertions, 0 deletions
diff --git a/netwerk/cache2/CacheIndex.h b/netwerk/cache2/CacheIndex.h new file mode 100644 index 000000000..dc72c346f --- /dev/null +++ b/netwerk/cache2/CacheIndex.h @@ -0,0 +1,1153 @@ +/* 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 "nsTHashtable.h" +#include "nsThreadUtils.h" +#include "nsWeakReference.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; + +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)!"); + +struct CacheIndexRecord { + SHA1Sum::Hash mHash; + uint32_t mFrecency; + OriginAttrsHash mOriginAttrsHash; + uint32_t mExpirationTime; + + /* + * 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 0011 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) + , mFlags(0) + {} +}; + +static_assert( + sizeof(CacheIndexRecord::mHash) + sizeof(CacheIndexRecord::mFrecency) + + sizeof(CacheIndexRecord::mOriginAttrsHash) + sizeof(CacheIndexRecord::mExpirationTime) + + 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) + { + NS_NOTREACHED("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->mFlags = aOther.mRec->mFlags; + return *this; + } + + void InitNew() + { + mRec->mFrecency = 0; + mRec->mExpirationTime = nsICacheEntry::NO_EXPIRATION_TIME; + mRec->mOriginAttrsHash = 0; + 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); + // 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; } + + // 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); + // 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->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=%llx, frecency=%u, expirationTime=%u, size=%u]", + this, LOGSHA1(mRec->mHash), IsFresh(), IsInitialized(), IsRemoved(), + IsDirty(), Anonymous(), OriginAttrsHash(), GetFrecency(), + GetExpirationTime(), GetFileSize())); + } + + static bool RecordMatchesLoadContextInfo(CacheIndexRecord *aRec, + nsILoadContextInfo *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; + + static const uint32_t kReservedMask = 0x03000000; + + // 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 | + kFileSizeUpdatedMask; + CacheIndexEntry::InitNew(); + } + + void SetFrecency(uint32_t aFrecency) + { + mUpdateFlags |= kFrecencyUpdatedMask; + CacheIndexEntry::SetFrecency(aFrecency); + } + + void SetExpirationTime(uint32_t aExpirationTime) + { + mUpdateFlags |= kExpirationUpdatedMask; + CacheIndexEntry::SetExpirationTime(aExpirationTime); + } + + 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 & kFileSizeUpdatedMask) { + aDst->mRec->mFlags = mRec->mFlags; + } else { + // Copy all flags except file size. + aDst->mRec->mFlags &= kFileSizeMask; + aDst->mRec->mFlags |= (mRec->mFlags & ~kFileSizeMask); + } + } + +private: + static const uint32_t kFrecencyUpdatedMask = 0x00000001; + static const uint32_t kExpirationUpdatedMask = 0x00000002; + static const uint32_t kFileSizeUpdatedMask = 0x00000004; + + 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 : 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 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 _pinned is non-null, it's filled with pinning status of the entry. + static nsresult HasEntry(const nsACString &aKey, EntryStatus *_retval, + bool *_pinned = nullptr); + static nsresult HasEntry(const SHA1Sum::Hash &hash, EntryStatus *_retval, + bool *_pinned = 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. + 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 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(); + void 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) + : mObserver(aWeakObserver) { } + virtual ~DiskConsumptionObserver() { + if (mObserver && !NS_IsMainThread()) { + NS_ReleaseOnMainThread(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 |