diff options
Diffstat (limited to 'netwerk/cache2/CacheEntry.h')
| -rw-r--r-- | netwerk/cache2/CacheEntry.h | 418 |
1 files changed, 418 insertions, 0 deletions
diff --git a/netwerk/cache2/CacheEntry.h b/netwerk/cache2/CacheEntry.h new file mode 100644 index 000000000..7331be2a4 --- /dev/null +++ b/netwerk/cache2/CacheEntry.h @@ -0,0 +1,418 @@ +/* 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 CacheEntry__h__ +#define CacheEntry__h__ + +#include "nsICacheEntry.h" +#include "CacheFile.h" + +#include "nsIRunnable.h" +#include "nsIOutputStream.h" +#include "nsICacheEntryOpenCallback.h" +#include "nsICacheEntryDoomCallback.h" + +#include "nsCOMPtr.h" +#include "nsRefPtrHashtable.h" +#include "nsDataHashtable.h" +#include "nsHashKeys.h" +#include "nsString.h" +#include "nsCOMArray.h" +#include "nsThreadUtils.h" +#include "mozilla/Attributes.h" +#include "mozilla/Mutex.h" +#include "mozilla/TimeStamp.h" + +static inline uint32_t +PRTimeToSeconds(PRTime t_usec) +{ + PRTime usec_per_sec = PR_USEC_PER_SEC; + return uint32_t(t_usec /= usec_per_sec); +} + +#define NowInSeconds() PRTimeToSeconds(PR_Now()) + +class nsIOutputStream; +class nsIURI; +class nsIThread; + +namespace mozilla { +namespace net { + +class CacheStorageService; +class CacheStorage; +class CacheOutputCloseListener; +class CacheEntryHandle; + +class CacheEntry final : public nsICacheEntry + , public nsIRunnable + , public CacheFileListener +{ +public: + NS_DECL_THREADSAFE_ISUPPORTS + NS_DECL_NSICACHEENTRY + NS_DECL_NSIRUNNABLE + + CacheEntry(const nsACString& aStorageID, const nsACString& aURI, const nsACString& aEnhanceID, + bool aUseDisk, bool aSkipSizeCheck, bool aPin); + + void AsyncOpen(nsICacheEntryOpenCallback* aCallback, uint32_t aFlags); + + CacheEntryHandle* NewHandle(); + // For a new and recreated entry w/o a callback, we need to wrap it + // with a handle to detect writing consumer is gone. + CacheEntryHandle* NewWriteHandle(); + +public: + uint32_t GetMetadataMemoryConsumption(); + nsCString const &GetStorageID() const { return mStorageID; } + nsCString const &GetEnhanceID() const { return mEnhanceID; } + nsCString const &GetURI() const { return mURI; } + // Accessible at any time + bool IsUsingDisk() const { return mUseDisk; } + bool IsReferenced() const; + bool IsFileDoomed(); + bool IsDoomed() const { return mIsDoomed; } + bool IsPinned() const { return mPinned; } + + // Methods for entry management (eviction from memory), + // called only on the management thread. + + // TODO make these inline + double GetFrecency() const; + uint32_t GetExpirationTime() const; + uint32_t UseCount() const { return mUseCount; } + + bool IsRegistered() const; + bool CanRegister() const; + void SetRegistered(bool aRegistered); + + TimeStamp const& LoadStart() const { return mLoadStart; } + + enum EPurge { + PURGE_DATA_ONLY_DISK_BACKED, + PURGE_WHOLE_ONLY_DISK_BACKED, + PURGE_WHOLE, + }; + + bool DeferOrBypassRemovalOnPinStatus(bool aPinned); + bool Purge(uint32_t aWhat); + void PurgeAndDoom(); + void DoomAlreadyRemoved(); + + nsresult HashingKeyWithStorage(nsACString &aResult) const; + nsresult HashingKey(nsACString &aResult) const; + + static nsresult HashingKey(nsCSubstring const& aStorageID, + nsCSubstring const& aEnhanceID, + nsIURI* aURI, + nsACString &aResult); + + static nsresult HashingKey(nsCSubstring const& aStorageID, + nsCSubstring const& aEnhanceID, + nsCSubstring const& aURISpec, + nsACString &aResult); + + // Accessed only on the service management thread + double mFrecency; + ::mozilla::Atomic<uint32_t, ::mozilla::Relaxed> mSortingExpirationTime; + + // Memory reporting + size_t SizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf) const; + size_t SizeOfIncludingThis(mozilla::MallocSizeOf mallocSizeOf) const; + +private: + virtual ~CacheEntry(); + + // CacheFileListener + NS_IMETHOD OnFileReady(nsresult aResult, bool aIsNew) override; + NS_IMETHOD OnFileDoomed(nsresult aResult) override; + + // Keep the service alive during life-time of an entry + RefPtr<CacheStorageService> mService; + + // We must monitor when a cache entry whose consumer is responsible + // for writing it the first time gets released. We must then invoke + // waiting callbacks to not break the chain. + class Callback + { + public: + Callback(CacheEntry* aEntry, + nsICacheEntryOpenCallback *aCallback, + bool aReadOnly, bool aCheckOnAnyThread, bool aSecret); + // Special constructor for Callback objects added to the chain + // just to ensure proper defer dooming (recreation) of this entry. + Callback(CacheEntry* aEntry, bool aDoomWhenFoundInPinStatus); + Callback(Callback const &aThat); + ~Callback(); + + // Called when this callback record changes it's owning entry, + // mainly during recreation. + void ExchangeEntry(CacheEntry* aEntry); + + // Returns true when an entry is about to be "defer" doomed and this is + // a "defer" callback. + bool DeferDoom(bool *aDoom) const; + + // We are raising reference count here to take into account the pending + // callback (that virtually holds a ref to this entry before it gets + // it's pointer). + RefPtr<CacheEntry> mEntry; + nsCOMPtr<nsICacheEntryOpenCallback> mCallback; + nsCOMPtr<nsIThread> mTargetThread; + bool mReadOnly : 1; + bool mRevalidating : 1; + bool mCheckOnAnyThread : 1; + bool mRecheckAfterWrite : 1; + bool mNotWanted : 1; + bool mSecret : 1; + + // These are set only for the defer-doomer Callback instance inserted + // to the callback chain. When any of these is set and also any of + // the corressponding flags on the entry is set, this callback will + // indicate (via DeferDoom()) the entry have to be recreated/doomed. + bool mDoomWhenFoundPinned : 1; + bool mDoomWhenFoundNonPinned : 1; + + nsresult OnCheckThread(bool *aOnCheckThread) const; + nsresult OnAvailThread(bool *aOnAvailThread) const; + }; + + // Since OnCacheEntryAvailable must be invoked on the main thread + // we need a runnable for it... + class AvailableCallbackRunnable : public Runnable + { + public: + AvailableCallbackRunnable(CacheEntry* aEntry, + Callback const &aCallback) + : mEntry(aEntry) + , mCallback(aCallback) + {} + + private: + NS_IMETHOD Run() override + { + mEntry->InvokeAvailableCallback(mCallback); + return NS_OK; + } + + RefPtr<CacheEntry> mEntry; + Callback mCallback; + }; + + // Since OnCacheEntryDoomed must be invoked on the main thread + // we need a runnable for it... + class DoomCallbackRunnable : public Runnable + { + public: + DoomCallbackRunnable(CacheEntry* aEntry, nsresult aRv) + : mEntry(aEntry), mRv(aRv) {} + + private: + NS_IMETHOD Run() override + { + nsCOMPtr<nsICacheEntryDoomCallback> callback; + { + mozilla::MutexAutoLock lock(mEntry->mLock); + mEntry->mDoomCallback.swap(callback); + } + + if (callback) + callback->OnCacheEntryDoomed(mRv); + return NS_OK; + } + + RefPtr<CacheEntry> mEntry; + nsresult mRv; + }; + + // Starts the load or just invokes the callback, bypasses (when required) + // if busy. Returns true on job done, false on bypass. + bool Open(Callback & aCallback, bool aTruncate, bool aPriority, bool aBypassIfBusy); + // Loads from disk asynchronously + bool Load(bool aTruncate, bool aPriority); + + void RememberCallback(Callback & aCallback); + void InvokeCallbacksLock(); + void InvokeCallbacks(); + bool InvokeCallbacks(bool aReadOnly); + bool InvokeCallback(Callback & aCallback); + void InvokeAvailableCallback(Callback const & aCallback); + void OnFetched(Callback const & aCallback); + + nsresult OpenOutputStreamInternal(int64_t offset, nsIOutputStream * *_retval); + nsresult OpenInputStreamInternal(int64_t offset, const char *aAltDataType, nsIInputStream * *_retval); + + void OnHandleClosed(CacheEntryHandle const* aHandle); + +private: + friend class CacheEntryHandle; + // Increment/decrements the number of handles keeping this entry. + void AddHandleRef() { ++mHandlesCount; } + void ReleaseHandleRef() { --mHandlesCount; } + // Current number of handles keeping this entry. + uint32_t HandlesCount() const { return mHandlesCount; } + +private: + friend class CacheOutputCloseListener; + void OnOutputClosed(); + +private: + // Schedules a background operation on the management thread. + // When executed on the management thread directly, the operation(s) + // is (are) executed immediately. + void BackgroundOp(uint32_t aOperation, bool aForceAsync = false); + void StoreFrecency(double aFrecency); + + // Called only from DoomAlreadyRemoved() + void DoomFile(); + // When this entry is doomed the first time, this method removes + // any force-valid timing info for this entry. + void RemoveForcedValidity(); + + already_AddRefed<CacheEntryHandle> ReopenTruncated(bool aMemoryOnly, + nsICacheEntryOpenCallback* aCallback); + void TransferCallbacks(CacheEntry & aFromEntry); + + mozilla::Mutex mLock; + + // Reflects the number of existing handles for this entry + ::mozilla::ThreadSafeAutoRefCnt mHandlesCount; + + nsTArray<Callback> mCallbacks; + nsCOMPtr<nsICacheEntryDoomCallback> mDoomCallback; + + RefPtr<CacheFile> mFile; + + // Using ReleaseAcquire since we only control access to mFile with this. + // When mFileStatus is read and found success it is ensured there is mFile and + // that it is after a successful call to Init(). + ::mozilla::Atomic<nsresult, ::mozilla::ReleaseAcquire> mFileStatus; + nsCString mURI; + nsCString mEnhanceID; + nsCString mStorageID; + + // mUseDisk, mSkipSizeCheck, mIsDoomed are plain "bool", not "bool:1", + // so as to avoid bitfield races with the byte containing + // mSecurityInfoLoaded et al. See bug 1278524. + // + // Whether it's allowed to persist the data to disk + bool const mUseDisk; + // Whether it should skip max size check. + bool const mSkipSizeCheck; + // Set when entry is doomed with AsyncDoom() or DoomAlreadyRemoved(). + bool mIsDoomed; + + // Following flags are all synchronized with the cache entry lock. + + // Whether security info has already been looked up in metadata. + bool mSecurityInfoLoaded : 1; + // Prevents any callback invocation + bool mPreventCallbacks : 1; + // true: after load and an existing file, or after output stream has been opened. + // note - when opening an input stream, and this flag is false, output stream + // is open along ; this makes input streams on new entries behave correctly + // when EOF is reached (WOULD_BLOCK is returned). + // false: after load and a new file, or dropped to back to false when a writer + // fails to open an output stream. + bool mHasData : 1; + // The indication of pinning this entry was open with + bool mPinned : 1; + // Whether the pinning state of the entry is known (equals to the actual state + // of the cache file) + bool mPinningKnown : 1; + + static char const * StateString(uint32_t aState); + + enum EState { // transiting to: + NOTLOADED = 0, // -> LOADING | EMPTY + LOADING = 1, // -> EMPTY | READY + EMPTY = 2, // -> WRITING + WRITING = 3, // -> EMPTY | READY + READY = 4, // -> REVALIDATING + REVALIDATING = 5 // -> READY + }; + + // State of this entry. + EState mState; + + enum ERegistration { + NEVERREGISTERED = 0, // The entry has never been registered + REGISTERED = 1, // The entry is stored in the memory pool index + DEREGISTERED = 2 // The entry has been removed from the pool + }; + + // Accessed only on the management thread. Records the state of registration + // this entry in the memory pool intermediate cache. + ERegistration mRegistration; + + // If a new (empty) entry is requested to open an input stream before + // output stream has been opened, we must open output stream internally + // on CacheFile and hold until writer releases the entry or opens the output + // stream for read (then we trade him mOutputStream). + nsCOMPtr<nsIOutputStream> mOutputStream; + + // Weak reference to the current writter. There can be more then one + // writer at a time and OnHandleClosed() must be processed only for the + // current one. + CacheEntryHandle* mWriter; + + // Background thread scheduled operation. Set (under the lock) one + // of this flags to tell the background thread what to do. + class Ops { + public: + static uint32_t const REGISTER = 1 << 0; + static uint32_t const FRECENCYUPDATE = 1 << 1; + static uint32_t const CALLBACKS = 1 << 2; + static uint32_t const UNREGISTER = 1 << 3; + + Ops() : mFlags(0) { } + uint32_t Grab() { uint32_t flags = mFlags; mFlags = 0; return flags; } + bool Set(uint32_t aFlags) { if (mFlags & aFlags) return false; mFlags |= aFlags; return true; } + private: + uint32_t mFlags; + } mBackgroundOperations; + + nsCOMPtr<nsISupports> mSecurityInfo; + int64_t mPredictedDataSize; + mozilla::TimeStamp mLoadStart; + uint32_t mUseCount; +}; + + +class CacheEntryHandle : public nsICacheEntry +{ +public: + explicit CacheEntryHandle(CacheEntry* aEntry); + CacheEntry* Entry() const { return mEntry; } + + NS_DECL_THREADSAFE_ISUPPORTS + NS_FORWARD_NSICACHEENTRY(mEntry->) +private: + virtual ~CacheEntryHandle(); + RefPtr<CacheEntry> mEntry; +}; + + +class CacheOutputCloseListener final : public Runnable +{ +public: + void OnOutputClosed(); + +private: + friend class CacheEntry; + + virtual ~CacheOutputCloseListener(); + + NS_DECL_NSIRUNNABLE + explicit CacheOutputCloseListener(CacheEntry* aEntry); + +private: + RefPtr<CacheEntry> mEntry; +}; + +} // namespace net +} // namespace mozilla + +#endif |