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/* 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
#include <algorithm>
#include <math.h>
#include "CacheEntry.h"
#include "CacheFileUtils.h"
#include "CacheIndex.h"
#include "CacheLog.h"
#include "CacheObserver.h"
#include "CacheStorageService.h"
#include "mozilla/IntegerPrintfMacros.h"
#include "mozilla/Telemetry.h"
#include "mozilla/psm/TransportSecurityInfo.h"
#include "nsComponentManagerUtils.h"
#include "nsIAsyncOutputStream.h"
#include "nsICacheEntryOpenCallback.h"
#include "nsICacheStorage.h"
#include "nsIInputStream.h"
#include "nsIOutputStream.h"
#include "nsISeekableStream.h"
#include "nsISizeOf.h"
#include "nsIURI.h"
#include "nsNetCID.h"
#include "nsProxyRelease.h"
#include "nsServiceManagerUtils.h"
#include "nsString.h"
#include "nsThreadUtils.h"
namespace mozilla::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) {
#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));
}
NS_IMETHODIMP CacheEntryHandle::Dismiss() {
LOG(("CacheEntryHandle::Dismiss %p", this));
if (mClosed.compareExchange(false, true)) {
mEntry->OnHandleClosed(this);
return NS_OK;
}
LOG((" already dropped"));
return NS_ERROR_UNEXPECTED;
}
CacheEntryHandle::~CacheEntryHandle() {
mEntry->ReleaseHandleRef();
Dismiss();
LOG(("CacheEntryHandle::~CacheEntryHandle %p", this));
}
// CacheEntry::Callback
CacheEntry::Callback::Callback(CacheEntry* aEntry,
nsICacheEntryOpenCallback* aCallback,
bool aReadOnly, bool aCheckOnAnyThread,
bool aSecret)
: mEntry(aEntry),
mCallback(aCallback),
mTarget(GetCurrentSerialEventTarget()),
mReadOnly(aReadOnly),
mRevalidating(false),
mCheckOnAnyThread(aCheckOnAnyThread),
mRecheckAfterWrite(false),
mNotWanted(false),
mSecret(aSecret),
mDoomWhenFoundPinned(false),
mDoomWhenFoundNonPinned(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* aEntry,
bool aDoomWhenFoundInPinStatus)
: mEntry(aEntry),
mReadOnly(false),
mRevalidating(false),
mCheckOnAnyThread(true),
mRecheckAfterWrite(false),
mNotWanted(false),
mSecret(false),
mDoomWhenFoundPinned(aDoomWhenFoundInPinStatus),
mDoomWhenFoundNonPinned(!aDoomWhenFoundInPinStatus) {
MOZ_COUNT_CTOR(CacheEntry::Callback);
MOZ_ASSERT(mEntry->HandlesCount());
mEntry->AddHandleRef();
}
CacheEntry::Callback::Callback(CacheEntry::Callback const& aThat)
: mEntry(aThat.mEntry),
mCallback(aThat.mCallback),
mTarget(aThat.mTarget),
mReadOnly(aThat.mReadOnly),
mRevalidating(aThat.mRevalidating),
mCheckOnAnyThread(aThat.mCheckOnAnyThread),
mRecheckAfterWrite(aThat.mRecheckAfterWrite),
mNotWanted(aThat.mNotWanted),
mSecret(aThat.mSecret),
mDoomWhenFoundPinned(aThat.mDoomWhenFoundPinned),
mDoomWhenFoundNonPinned(aThat.mDoomWhenFoundNonPinned) {
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("CacheEntry::Callback::mCallback", mCallback, mTarget);
mEntry->ReleaseHandleRef();
MOZ_COUNT_DTOR(CacheEntry::Callback);
}
// We have locks on both this and aEntry
void CacheEntry::Callback::ExchangeEntry(CacheEntry* aEntry) {
aEntry->mLock.AssertCurrentThreadOwns();
mEntry->mLock.AssertCurrentThreadOwns();
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;
}
// This is called on entries in another entry's mCallback array, under the lock
// of that other entry. No other threads can access this entry at this time.
bool CacheEntry::Callback::DeferDoom(bool* aDoom) const
MOZ_NO_THREAD_SAFETY_ANALYSIS {
MOZ_ASSERT(mEntry->mPinningKnown);
if (MOZ_UNLIKELY(mDoomWhenFoundNonPinned) ||
MOZ_UNLIKELY(mDoomWhenFoundPinned)) {
*aDoom =
(MOZ_UNLIKELY(mDoomWhenFoundNonPinned) &&
MOZ_LIKELY(!mEntry->mPinned)) ||
(MOZ_UNLIKELY(mDoomWhenFoundPinned) && MOZ_UNLIKELY(mEntry->mPinned));
return true;
}
return false;
}
nsresult CacheEntry::Callback::OnCheckThread(bool* aOnCheckThread) const {
if (!mCheckOnAnyThread) {
// Check we are on the target
return mTarget->IsOnCurrentThread(aOnCheckThread);
}
// We can invoke check anywhere
*aOnCheckThread = true;
return NS_OK;
}
nsresult CacheEntry::Callback::OnAvailThread(bool* aOnAvailThread) const {
return mTarget->IsOnCurrentThread(aOnAvailThread);
}
// CacheEntry
NS_IMPL_ISUPPORTS(CacheEntry, nsIRunnable, CacheFileListener)
/* static */
uint64_t CacheEntry::GetNextId() {
static Atomic<uint64_t, Relaxed> id(0);
return ++id;
}
CacheEntry::CacheEntry(const nsACString& aStorageID, const nsACString& aURI,
const nsACString& aEnhanceID, bool aUseDisk,
bool aSkipSizeCheck, bool aPin)
: mURI(aURI),
mEnhanceID(aEnhanceID),
mStorageID(aStorageID),
mUseDisk(aUseDisk),
mSkipSizeCheck(aSkipSizeCheck),
mPinned(aPin),
mSecurityInfoLoaded(false),
mPreventCallbacks(false),
mHasData(false),
mPinningKnown(false),
mBypassWriterLock(false),
mCacheEntryId(GetNextId()) {
LOG(("CacheEntry::CacheEntry [this=%p]", this));
mService = CacheStorageService::Self();
CacheStorageService::Self()->RecordMemoryOnlyEntry(this, !aUseDisk,
true /* overwrite */);
}
CacheEntry::~CacheEntry() { LOG(("CacheEntry::~CacheEntry [this=%p]", this)); }
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 "?";
}
nsresult CacheEntry::HashingKeyWithStorage(nsACString& aResult) const {
return HashingKey(mStorageID, mEnhanceID, mURI, aResult);
}
nsresult CacheEntry::HashingKey(nsACString& aResult) const {
return HashingKey(""_ns, mEnhanceID, mURI, aResult);
}
// static
nsresult CacheEntry::HashingKey(const nsACString& aStorageID,
const nsACString& aEnhanceID, nsIURI* aURI,
nsACString& aResult) {
nsAutoCString spec;
nsresult rv = aURI->GetAsciiSpec(spec);
NS_ENSURE_SUCCESS(rv, rv);
return HashingKey(aStorageID, aEnhanceID, spec, aResult);
}
// The hash key (which is also the filename) is:
// A[~B]:C
// Where A is the storage ID ([O<oa>,][a,][p,]), B is the optional 'id',
// and C is the URI 'oa' are the OriginAttributes in suffix form
// (i.e. |^key=value&key2=value2|)
// static
nsresult CacheEntry::HashingKey(const nsACString& aStorageID,
const nsACString& aEnhanceID,
const nsACString& 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.Assign(aStorageID);
if (!aEnhanceID.IsEmpty()) {
CacheFileUtils::AppendTagWithValue(aResult, '~', aEnhanceID);
}
// Appending directly
aResult.Append(':');
aResult.Append(aURISpec);
return NS_OK;
}
nsresult CacheEntry::SetDictionary(DictionaryCacheEntry* aDict) {
mDict = aDict;
mFile->SetDictionary(aDict);
return NS_OK;
}
void CacheEntry::AsyncOpen(nsICacheEntryOpenCallback* aCallback,
uint32_t aFlags) {
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;
bool secret = aFlags & nsICacheStorage::OPEN_SECRETLY;
if (MOZ_LOG_TEST(gCache2Log, LogLevel::Debug)) {
MutexAutoLock lock(mLock);
LOG(("CacheEntry::AsyncOpen [this=%p, state=%s, flags=%d, callback=%p]",
this, StateString(mState), aFlags, aCallback));
}
#ifdef DEBUG
{
// yes, if logging is on in DEBUG we'll take the lock twice in a row
MutexAutoLock lock(mLock);
MOZ_ASSERT(!readonly || !truncate, "Bad flags combination");
MOZ_ASSERT(!(truncate && mState > LOADING),
"Must not call truncate on already loaded entry");
}
#endif
Callback callback(this, aCallback, readonly, multithread, secret);
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) MOZ_REQUIRES(mLock) {
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);
bool reportMiss = false;
// 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:
// Doesn't apply to memory-only entries, Load() is called only once
// for them and never again for their session lifetime.
if (!aTruncate && mUseDisk) {
LOG(
(" entry doesn't exist according information from the index, "
"truncating"));
reportMiss = true;
aTruncate = true;
}
break;
case CacheIndex::EXISTS:
case CacheIndex::DO_NOT_KNOW:
if (!mUseDisk) {
LOG(
(" entry open as memory-only, but there is a file, status=%d, "
"dooming it",
status));
CacheFileIOManager::DoomFileByKey(fileKey, nullptr);
}
break;
}
}
}
mFile = new CacheFile();
BackgroundOp(Ops::REGISTER);
bool directLoad = aTruncate || !mUseDisk;
if (directLoad) {
// mLoadStart will be used to calculate telemetry of life-time of this
// entry. Low resulution is then enough.
mLoadStart = TimeStamp::NowLoRes();
mPinningKnown = true;
} else {
mLoadStart = TimeStamp::Now();
}
{
mozilla::MutexAutoUnlock unlock(mLock);
if (reportMiss) {
CacheFileUtils::DetailedCacheHitTelemetry::AddRecord(
CacheFileUtils::DetailedCacheHitTelemetry::MISS, mLoadStart);
}
LOG((" performing load, file=%p", mFile.get()));
if (NS_SUCCEEDED(rv)) {
rv = mFile->Init(fileKey, aTruncate, !mUseDisk, mSkipSizeCheck, aPriority,
mPinned, 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".
mFileStatus = NS_OK;
mState = EMPTY;
}
return mState == LOADING;
}
NS_IMETHODIMP CacheEntry::OnFileReady(nsresult aResult, bool aIsNew) {
LOG(("CacheEntry::OnFileReady [this=%p, rv=0x%08" PRIx32 ", new=%d]", this,
static_cast<uint32_t>(aResult), aIsNew));
MOZ_ASSERT(!mLoadStart.IsNull());
if (NS_SUCCEEDED(aResult)) {
if (aIsNew) {
CacheFileUtils::DetailedCacheHitTelemetry::AddRecord(
CacheFileUtils::DetailedCacheHitTelemetry::MISS, mLoadStart);
} else {
CacheFileUtils::DetailedCacheHitTelemetry::AddRecord(
CacheFileUtils::DetailedCacheHitTelemetry::HIT, mLoadStart);
}
}
// OnFileReady, that is the only code that can transit from LOADING
// to any follow-on state and can only be invoked ones on an entry.
// 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;
mPinned = mFile->IsPinned();
mPinningKnown = true;
LOG((" pinning=%d", (bool)mPinned));
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) {
RefPtr<DoomCallbackRunnable> event =
new DoomCallbackRunnable(this, aResult);
NS_DispatchToMainThread(event);
}
return NS_OK;
}
already_AddRefed<CacheEntryHandle> CacheEntry::ReopenTruncated(
bool aMemoryOnly, nsICacheEntryOpenCallback* aCallback)
MOZ_REQUIRES(mLock) {
LOG(("CacheEntry::ReopenTruncated [this=%p]", this));
mLock.AssertCurrentThreadOwns();
// Hold callbacks invocation, AddStorageEntry would invoke from doom
// prematurely
mPreventCallbacks = true;
RefPtr<CacheEntryHandle> handle;
RefPtr<CacheEntry> newEntry;
{
if (mPinned) {
MOZ_ASSERT(mUseDisk);
// We want to pin even no-store entries (the case we recreate a disk entry
// as a memory-only entry.)
aMemoryOnly = false;
}
mozilla::MutexAutoUnlock unlock(mLock);
// The following call dooms this entry (calls DoomAlreadyRemoved on us)
nsresult rv = CacheStorageService::Self()->AddStorageEntry(
GetStorageID(), GetURI(), GetEnhanceID(), mUseDisk && !aMemoryOnly,
mSkipSizeCheck, mPinned,
nsICacheStorage::OPEN_TRUNCATE, // truncate existing (this one)
getter_AddRefs(handle));
if (NS_SUCCEEDED(rv)) {
newEntry = handle->Entry();
LOG((" exchanged entry %p by entry %p, rv=0x%08" PRIx32, this,
newEntry.get(), static_cast<uint32_t>(rv)));
newEntry->AsyncOpen(aCallback, nsICacheStorage::OPEN_TRUNCATE);
} else {
LOG((" exchanged of entry %p failed, rv=0x%08" PRIx32, this,
static_cast<uint32_t>(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.
RefPtr<CacheEntryHandle> writeHandle = newEntry->NewWriteHandle();
return writeHandle.forget();
}
void CacheEntry::TransferCallbacks(CacheEntry& aFromEntry) {
mozilla::MutexAutoLock lock(mLock);
aFromEntry.mLock.AssertCurrentThreadOwns();
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 (unfortunately, 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) MOZ_REQUIRES(mLock) {
mLock.AssertCurrentThreadOwns();
RefPtr<CacheEntryHandle> recreatedHandle;
uint32_t i = 0;
while (i < mCallbacks.Length()) {
if (mPreventCallbacks) {
LOG((" callbacks prevented!"));
return false;
}
if (!mIsDoomed && (mState == WRITING || mState == REVALIDATING)) {
if (!mBypassWriterLock) {
LOG((" entry is being written/revalidated"));
return false;
}
LOG((" entry is being written/revalidated but bypassing writer lock"));
}
bool recreate;
if (mCallbacks[i].DeferDoom(&recreate)) {
mCallbacks.RemoveElementAt(i);
if (!recreate) {
continue;
}
LOG((" defer doom marker callback hit positive, recreating"));
recreatedHandle = ReopenTruncated(!mUseDisk, nullptr);
break;
}
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
rv = mCallbacks[i].mTarget->Dispatch(
NewRunnableMethod("net::CacheEntry::InvokeCallbacksLock", this,
&CacheEntry::InvokeCallbacksLock),
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.
size_t pos = std::min(mCallbacks.Length(), static_cast<size_t>(i));
mCallbacks.InsertElementAt(pos, callback);
++i;
}
}
if (recreatedHandle) {
// Must be released outside of the lock, enters InvokeCallback on the new
// entry
mozilla::MutexAutoUnlock unlock(mLock);
recreatedHandle = nullptr;
}
return true;
}
bool CacheEntry::InvokeCallback(Callback& aCallback) MOZ_REQUIRES(mLock) {
mLock.AssertCurrentThreadOwns();
LOG(("CacheEntry::InvokeCallback [this=%p, state=%s, cb=%p]", this,
StateString(mState), aCallback.mCallback.get()));
// 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) {
if (!mBypassWriterLock) {
// 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;
}
LOG((" entry is being written/revalidated but bypassing writer lock"));
}
// 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);
RefPtr<CacheEntryHandle> handle = NewHandle();
nsresult rv =
aCallback.mCallback->OnCacheEntryCheck(handle, &checkResult);
LOG((" OnCacheEntryCheck: rv=0x%08" PRIx32 ", result=%" PRId32,
static_cast<uint32_t>(rv), static_cast<uint32_t>(checkResult)));
if (NS_FAILED(rv)) checkResult = ENTRY_NOT_WANTED;
}
aCallback.mRevalidating = checkResult == ENTRY_NEEDS_REVALIDATION;
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) {
nsresult rv;
uint32_t state;
{
mozilla::MutexAutoLock lock(mLock);
state = mState;
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));
// 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
RefPtr<AvailableCallbackRunnable> event =
new AvailableCallbackRunnable(this, aCallback);
rv = aCallback.mTarget->Dispatch(event, nsIEventTarget::DISPATCH_NORMAL);
LOG((" redispatched, (rv = 0x%08" PRIx32 ")", static_cast<uint32_t>(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,
NS_ERROR_CACHE_KEY_NOT_FOUND);
return;
}
if (state == READY) {
LOG((" ready/has-meta, notifying OCEA with entry and NS_OK"));
if (!aCallback.mSecret) {
mozilla::MutexAutoLock lock(mLock);
BackgroundOp(Ops::FRECENCYUPDATE);
}
OnFetched(aCallback);
RefPtr<CacheEntryHandle> handle = NewHandle();
aCallback.mCallback->OnCacheEntryAvailable(handle, false, NS_OK);
return;
}
// R/O callbacks may do revalidation, let them fall through
if (aCallback.mReadOnly && !aCallback.mRevalidating) {
LOG(
(" r/o and not ready, notifying OCEA with "
"NS_ERROR_CACHE_KEY_NOT_FOUND"));
aCallback.mCallback->OnCacheEntryAvailable(nullptr, false,
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.
OnFetched(aCallback);
RefPtr<CacheEntryHandle> handle = NewWriteHandle();
rv = aCallback.mCallback->OnCacheEntryAvailable(handle, state == WRITING,
NS_OK);
if (NS_FAILED(rv)) {
LOG((" writing/revalidating failed (0x%08" PRIx32 ")",
static_cast<uint32_t>(rv)));
// Consumer given a new entry failed to take care of the entry.
OnHandleClosed(handle);
return;
}
LOG((" writing/revalidating"));
}
void CacheEntry::OnFetched(Callback const& aCallback) {
if (NS_SUCCEEDED(mFileStatus) && !aCallback.mSecret) {
// Let the last-fetched and fetch-count properties be updated.
mFile->OnFetched();
}
}
CacheEntryHandle* CacheEntry::NewHandle() { return new CacheEntryHandle(this); }
CacheEntryHandle* CacheEntry::NewWriteHandle() {
mozilla::MutexAutoLock lock(mLock);
// Ignore the OPEN_SECRETLY flag on purpose here, which should actually be
// used only along with OPEN_READONLY, but there is no need to enforce that.
BackgroundOp(Ops::FRECENCYUPDATE);
return (mWriter = NewHandle());
}
void CacheEntry::OnHandleClosed(CacheEntryHandle const* aHandle) {
mozilla::MutexAutoLock lock(mLock);
LOG(("CacheEntry::OnHandleClosed [this=%p, state=%s, handle=%p]", this,
StateString(mState), aHandle));
if (mIsDoomed && NS_SUCCEEDED(mFileStatus) &&
// Note: mHandlesCount is dropped before this method is called
(mHandlesCount == 0 ||
(mHandlesCount == 1 && mWriter && mWriter != aHandle))) {
// This entry is no longer referenced from outside and is doomed.
// We can do this also when there is just reference from the writer,
// no one else could ever reach the written data.
// Tell the file to kill the handle, i.e. bypass any I/O operations
// on it except removing the file.
mFile->Kill();
}
if (mWriter != aHandle) {
LOG((" not the writer"));
return;
}
if (mOutputStream) {
LOG((" abandoning phantom output stream"));
// 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;
// This asynchronously ends up invoking callbacks on this entry
// through OnOutputClosed() call.
mOutputStream->Close();
mOutputStream = nullptr;
} else {
// We must always redispatch, otherwise there is a risk of stack
// overflow. This code can recurse deeply. It won't execute sooner
// than we release mLock.
BackgroundOp(Ops::CALLBACKS, true);
}
mWriter = nullptr;
// Reset bypass flag when writer is cleared
if (mBypassWriterLock) {
mBypassWriterLock = false;
LOG((" reset bypass writer lock flag due to writer cleared"));
}
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;
}
}
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;
}
void CacheEntry::SetBypassWriterLock(bool aBypass) {
mozilla::MutexAutoLock lock(mLock);
LOG(("CacheEntry::SetBypassWriterLock [this=%p, bypass=%d]", this, aBypass));
mBypassWriterLock = aBypass;
if (aBypass) {
// Invoke callbacks that were blocked by writer state
InvokeCallbacks();
}
}
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
nsresult 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;
}
nsresult CacheEntry::GetKey(nsACString& aKey) {
aKey.Assign(mURI);
return NS_OK;
}
nsresult CacheEntry::GetCacheEntryId(uint64_t* aCacheEntryId) {
*aCacheEntryId = mCacheEntryId;
return NS_OK;
}
nsresult CacheEntry::GetFetchCount(uint32_t* aFetchCount) {
NS_ENSURE_SUCCESS(mFileStatus, NS_ERROR_NOT_AVAILABLE);
return mFile->GetFetchCount(aFetchCount);
}
nsresult CacheEntry::GetLastFetched(uint32_t* aLastFetched) {
NS_ENSURE_SUCCESS(mFileStatus, NS_ERROR_NOT_AVAILABLE);
return mFile->GetLastFetched(aLastFetched);
}
nsresult CacheEntry::GetLastModified(uint32_t* aLastModified) {
NS_ENSURE_SUCCESS(mFileStatus, NS_ERROR_NOT_AVAILABLE);
return mFile->GetLastModified(aLastModified);
}
nsresult CacheEntry::GetExpirationTime(uint32_t* aExpirationTime) {
NS_ENSURE_SUCCESS(mFileStatus, NS_ERROR_NOT_AVAILABLE);
return mFile->GetExpirationTime(aExpirationTime);
}
nsresult CacheEntry::GetOnStartTime(uint64_t* aTime) {
NS_ENSURE_SUCCESS(mFileStatus, NS_ERROR_NOT_AVAILABLE);
return mFile->GetOnStartTime(aTime);
}
nsresult CacheEntry::GetOnStopTime(uint64_t* aTime) {
NS_ENSURE_SUCCESS(mFileStatus, NS_ERROR_NOT_AVAILABLE);
return mFile->GetOnStopTime(aTime);
}
nsresult CacheEntry::GetReadyOrRevalidating(bool* aReady) {
mozilla::MutexAutoLock lock(mLock);
*aReady = (mState == READY || mState == REVALIDATING);
return NS_OK;
}
nsresult CacheEntry::SetNetworkTimes(uint64_t aOnStartTime,
uint64_t aOnStopTime) {
if (NS_SUCCEEDED(mFileStatus)) {
return mFile->SetNetworkTimes(aOnStartTime, aOnStopTime);
}
return NS_ERROR_NOT_AVAILABLE;
}
nsresult CacheEntry::SetContentType(uint8_t aContentType) {
NS_ENSURE_ARG_MAX(aContentType, nsICacheEntry::CONTENT_TYPE_LAST - 1);
if (NS_SUCCEEDED(mFileStatus)) {
return mFile->SetContentType(aContentType);
}
return NS_ERROR_NOT_AVAILABLE;
}
nsresult CacheEntry::GetIsForcedValid(bool* aIsForcedValid) {
NS_ENSURE_ARG(aIsForcedValid);
#ifdef DEBUG
{
mozilla::MutexAutoLock lock(mLock);
MOZ_ASSERT(mState > LOADING);
}
#endif
if (mPinned) {
*aIsForcedValid = true;
return NS_OK;
}
nsAutoCString key;
nsresult rv = HashingKey(key);
if (NS_FAILED(rv)) {
return rv;
}
*aIsForcedValid =
CacheStorageService::Self()->IsForcedValidEntry(mStorageID, key);
LOG(("CacheEntry::GetIsForcedValid [this=%p, IsForcedValid=%d]", this,
*aIsForcedValid));
return NS_OK;
}
nsresult CacheEntry::ForceValidFor(uint32_t aSecondsToTheFuture) {
LOG(("CacheEntry::ForceValidFor [this=%p, aSecondsToTheFuture=%d]", this,
aSecondsToTheFuture));
nsAutoCString key;
nsresult rv = HashingKey(key);
if (NS_FAILED(rv)) {
return rv;
}
CacheStorageService::Self()->ForceEntryValidFor(mStorageID, key,
aSecondsToTheFuture);
return NS_OK;
}
nsresult CacheEntry::MarkForcedValidUse() {
LOG(("CacheEntry::MarkForcedValidUse [this=%p, ]", this));
nsAutoCString key;
nsresult rv = HashingKey(key);
if (NS_FAILED(rv)) {
return rv;
}
CacheStorageService::Self()->MarkForcedValidEntryUse(mStorageID, key);
return NS_OK;
}
nsresult 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;
}
nsresult CacheEntry::OpenInputStream(int64_t offset, nsIInputStream** _retval) {
LOG(("CacheEntry::OpenInputStream [this=%p]", this));
return OpenInputStreamInternal(offset, nullptr, _retval);
}
nsresult CacheEntry::OpenAlternativeInputStream(const nsACString& type,
nsIInputStream** _retval) {
LOG(("CacheEntry::OpenAlternativeInputStream [this=%p, type=%s]", this,
PromiseFlatCString(type).get()));
return OpenInputStreamInternal(0, PromiseFlatCString(type).get(), _retval);
}
nsresult CacheEntry::OpenInputStreamInternal(int64_t offset,
const char* aAltDataType,
nsIInputStream** _retval) {
LOG(("CacheEntry::OpenInputStreamInternal [this=%p]", this));
NS_ENSURE_SUCCESS(mFileStatus, NS_ERROR_NOT_AVAILABLE);
nsresult rv;
RefPtr<CacheEntryHandle> selfHandle = NewHandle();
nsCOMPtr<nsIInputStream> stream;
if (aAltDataType) {
rv = mFile->OpenAlternativeInputStream(selfHandle, aAltDataType,
getter_AddRefs(stream));
if (NS_FAILED(rv)) {
// Failure of this method may be legal when the alternative data requested
// is not available or of a different type. Console error logs are
// ensured by CacheFile::OpenAlternativeInputStream.
return rv;
}
} else {
rv = mFile->OpenInputStream(selfHandle, 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;
}
nsresult CacheEntry::OpenOutputStream(int64_t offset, int64_t predictedSize,
nsIOutputStream** _retval) {
LOG(("CacheEntry::OpenOutputStream [this=%p]", this));
nsresult rv;
mozilla::MutexAutoLock lock(mLock);
MOZ_ASSERT(mState > EMPTY);
if (mFile->EntryWouldExceedLimit(0, predictedSize, false)) {
LOG((" entry would exceed size limit"));
return NS_ERROR_FILE_TOO_BIG;
}
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::OpenAlternativeOutputStream(
const nsACString& type, int64_t predictedSize,
nsIAsyncOutputStream** _retval) {
LOG(("CacheEntry::OpenAlternativeOutputStream [this=%p, type=%s]", this,
PromiseFlatCString(type).get()));
nsresult rv;
if (type.IsEmpty()) {
// The empty string is reserved to mean no alt-data available.
return NS_ERROR_INVALID_ARG;
}
mozilla::MutexAutoLock lock(mLock);
if (!mHasData || mState < READY || mOutputStream || mIsDoomed) {
LOG((" entry not in state to write alt-data"));
return NS_ERROR_NOT_AVAILABLE;
}
if (mFile->EntryWouldExceedLimit(0, predictedSize, true)) {
LOG((" entry would exceed size limit"));
return NS_ERROR_FILE_TOO_BIG;
}
nsCOMPtr<nsIAsyncOutputStream> stream;
rv = mFile->OpenAlternativeOutputStream(
nullptr, PromiseFlatCString(type).get(), getter_AddRefs(stream));
NS_ENSURE_SUCCESS(rv, rv);
stream.swap(*_retval);
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);
}
RefPtr<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;
}
nsresult CacheEntry::GetSecurityInfo(nsITransportSecurityInfo** aSecurityInfo) {
{
mozilla::MutexAutoLock lock(mLock);
if (mSecurityInfoLoaded) {
*aSecurityInfo = do_AddRef(mSecurityInfo).take();
return NS_OK;
}
}
NS_ENSURE_SUCCESS(mFileStatus, NS_ERROR_NOT_AVAILABLE);
nsCString info;
nsresult rv = mFile->GetElement("security-info", getter_Copies(info));
NS_ENSURE_SUCCESS(rv, rv);
nsCOMPtr<nsITransportSecurityInfo> securityInfo;
if (!info.IsVoid()) {
rv = mozilla::psm::TransportSecurityInfo::Read(
info, getter_AddRefs(securityInfo));
NS_ENSURE_SUCCESS(rv, rv);
}
if (!securityInfo) {
return NS_ERROR_NOT_AVAILABLE;
}
{
mozilla::MutexAutoLock lock(mLock);
mSecurityInfo.swap(securityInfo);
mSecurityInfoLoaded = true;
*aSecurityInfo = do_AddRef(mSecurityInfo).take();
}
return NS_OK;
}
nsresult CacheEntry::SetSecurityInfo(nsITransportSecurityInfo* aSecurityInfo) {
nsresult rv;
NS_ENSURE_SUCCESS(mFileStatus, mFileStatus);
{
mozilla::MutexAutoLock lock(mLock);
mSecurityInfo = aSecurityInfo;
mSecurityInfoLoaded = true;
}
nsCString info;
if (aSecurityInfo) {
rv = aSecurityInfo->ToString(info);
NS_ENSURE_SUCCESS(rv, rv);
}
rv = mFile->SetElement("security-info", info.Length() ? info.get() : nullptr);
NS_ENSURE_SUCCESS(rv, rv);
return NS_OK;
}
nsresult 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;
}
nsresult 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
}
RemoveForcedValidity();
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;
}
nsresult CacheEntry::GetMetaDataElement(const char* aKey, char** aRetval) {
NS_ENSURE_SUCCESS(mFileStatus, NS_ERROR_NOT_AVAILABLE);
return mFile->GetElement(aKey, aRetval);
}
nsresult CacheEntry::SetMetaDataElement(const char* aKey, const char* aValue) {
NS_ENSURE_SUCCESS(mFileStatus, NS_ERROR_NOT_AVAILABLE);
return mFile->SetElement(aKey, aValue);
}
nsresult CacheEntry::VisitMetaData(nsICacheEntryMetaDataVisitor* aVisitor) {
NS_ENSURE_SUCCESS(mFileStatus, NS_ERROR_NOT_AVAILABLE);
return mFile->VisitMetaData(aVisitor);
}
nsresult 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;
// Reset bypass flag when transitioning to READY state
if (mBypassWriterLock) {
mBypassWriterLock = false;
LOG((" reset bypass writer lock flag due to state transition to READY"));
}
}
InvokeCallbacks();
return NS_OK;
}
nsresult CacheEntry::SetValid() {
nsCOMPtr<nsIOutputStream> outputStream;
{
mozilla::MutexAutoLock lock(mLock);
LOG(("CacheEntry::SetValid [this=%p, state=%s]", this,
StateString(mState)));
MOZ_ASSERT(mState > EMPTY);
mState = READY;
mHasData = true;
// Reset bypass flag when transitioning to READY state
if (mBypassWriterLock) {
mBypassWriterLock = false;
LOG((" reset bypass writer lock flag due to state transition to READY"));
}
InvokeCallbacks();
outputStream.swap(mOutputStream);
}
if (outputStream) {
LOG((" abandoning phantom output stream"));
outputStream->Close();
}
return NS_OK;
}
nsresult CacheEntry::Recreate(bool aMemoryOnly, nsICacheEntry** _retval) {
mozilla::MutexAutoLock lock(mLock);
LOG(("CacheEntry::Recreate [this=%p, state=%s]", this, StateString(mState)));
RefPtr<CacheEntryHandle> handle = ReopenTruncated(aMemoryOnly, nullptr);
if (handle) {
handle.forget(_retval);
return NS_OK;
}
BackgroundOp(Ops::CALLBACKS, true);
return NS_ERROR_NOT_AVAILABLE;
}
nsresult 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=%" PRId64, *aDataSize));
return NS_OK;
}
nsresult CacheEntry::GetAltDataSize(int64_t* aDataSize) {
LOG(("CacheEntry::GetAltDataSize [this=%p]", this));
if (NS_FAILED(mFileStatus)) {
return mFileStatus;
}
return mFile->GetAltDataSize(aDataSize);
}
nsresult CacheEntry::GetAltDataType(nsACString& aType) {
LOG(("CacheEntry::GetAltDataType [this=%p]", this));
if (NS_FAILED(mFileStatus)) {
return mFileStatus;
}
return mFile->GetAltDataType(aType);
}
nsresult CacheEntry::GetDiskStorageSizeInKB(uint32_t* aDiskStorageSize) {
if (NS_FAILED(mFileStatus)) {
return NS_ERROR_NOT_AVAILABLE;
}
return mFile->GetDiskStorageSizeInKB(aDiskStorageSize);
}
nsresult CacheEntry::GetLoadContextInfo(nsILoadContextInfo** aInfo) {
nsCOMPtr<nsILoadContextInfo> info = CacheFileUtils::ParseKey(mStorageID);
if (!info) {
return NS_ERROR_FAILURE;
}
info.forget(aInfo);
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::DeferOrBypassRemovalOnPinStatus(bool aPinned) {
LOG(("CacheEntry::DeferOrBypassRemovalOnPinStatus [this=%p]", this));
mozilla::MutexAutoLock lock(mLock);
if (mPinningKnown) {
LOG((" pinned=%d, caller=%d", (bool)mPinned, aPinned));
// Bypass when the pin status of this entry doesn't match the pin status
// caller wants to remove
return mPinned != aPinned;
}
LOG((" pinning unknown, caller=%d", aPinned));
// Oterwise, remember to doom after the status is determined for any
// callback opening the entry after this point...
Callback c(this, aPinned);
RememberCallback(c);
// ...and always bypass
return true;
}
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;
}
}
{
mozilla::MutexAutoLock lock(mLock);
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);
RemoveForcedValidity();
mIsDoomed = true;
// Pretend pinning is know. This entry is now doomed for good, so don't
// bother with defering doom because of unknown pinning state any more.
mPinningKnown = 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)) {
if (mHandlesCount == 0 || (mHandlesCount == 1 && mWriter)) {
// We kill the file also when there is just reference from the writer,
// no one else could ever reach the written data. Obvisouly also
// when there is no reference at all (should we ever end up here
// in that case.)
// Tell the file to kill the handle, i.e. bypass any I/O operations
// on it except removing the file.
mFile->Kill();
}
// 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::RemoveForcedValidity() {
mLock.AssertCurrentThreadOwns();
nsresult rv;
if (mIsDoomed) {
return;
}
nsAutoCString entryKey;
rv = HashingKey(entryKey);
if (NS_WARN_IF(NS_FAILED(rv))) {
return;
}
CacheStorageService::Self()->RemoveEntryForceValid(mStorageID, entryKey);
}
void CacheEntry::BackgroundOp(uint32_t aOperations, bool aForceAsync)
MOZ_REQUIRES(mLock) {
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<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...
NS_DispatchToMainThread(
NewRunnableMethod<double>("net::CacheEntry::StoreFrecency", this,
&CacheEntry::StoreFrecency, mFrecency));
}
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(double aFrecency) {
MOZ_ASSERT(NS_IsMainThread());
if (NS_SUCCEEDED(mFileStatus)) {
mFile->SetFrecency(FRECENCY2INT(aFrecency));
}
}
// CacheOutputCloseListener
CacheOutputCloseListener::CacheOutputCloseListener(CacheEntry* aEntry)
: Runnable("net::CacheOutputCloseListener"), mEntry(aEntry) {}
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.
// This function may be reached while XPCOM is already shutting down,
// and we might be unable to obtain the main thread or the sts. #1826661
if (NS_IsMainThread()) {
// If we're already on the main thread, dispatch to the main thread instead
// of the sts. Always dispatching to the sts can cause problems late in
//
// This may also avoid some unnecessary thread-hops when invoking callbacks,
// which can require that they be called on the main thread.
nsCOMPtr<nsIThread> thread;
nsresult rv = NS_GetMainThread(getter_AddRefs(thread));
if (NS_SUCCEEDED(rv)) {
MOZ_ALWAYS_SUCCEEDS(thread->Dispatch(do_AddRef(this)));
}
return;
}
nsCOMPtr<nsIEventTarget> sts =
do_GetService(NS_STREAMTRANSPORTSERVICE_CONTRACTID);
MOZ_DIAGNOSTIC_ASSERT(sts);
if (sts) {
MOZ_ALWAYS_SUCCEEDS(sts->Dispatch(do_AddRef(this)));
}
}
NS_IMETHODIMP CacheOutputCloseListener::Run() {
mEntry->OnOutputClosed();
return NS_OK;
}
// Memory reporting
size_t CacheEntry::SizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf) {
size_t n = 0;
MutexAutoLock lock(mLock);
n += mCallbacks.ShallowSizeOfExcludingThis(mallocSizeOf);
if (mFile) {
n += mFile->SizeOfIncludingThis(mallocSizeOf);
}
n += mURI.SizeOfExcludingThisIfUnshared(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 unfortunately cannot be reported. Handles are
// small, though.
// mSecurityInfo doesn't impl nsISizeOf.
return n;
}
size_t CacheEntry::SizeOfIncludingThis(mozilla::MallocSizeOf mallocSizeOf) {
return mallocSizeOf(this) + SizeOfExcludingThis(mallocSizeOf);
}
} // namespace mozilla::net