The Tor Browser: netwerk/cache/nsDiskCacheDevice.cpp@6474c204b198 (annotated)

netwerk/cache/nsDiskCacheDevice.cpp@6474c204b198 (annotated)

netwerk/cache/nsDiskCacheDevice.cpp

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
  *
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 #include <limits.h>
 #include "mozilla/DebugOnly.h"
 #include "nsCache.h"
 #include "nsIMemoryReporter.h"
 // include files for ftruncate (or equivalent)
 #if defined(XP_UNIX)
 #include <unistd.h>
 #elif defined(XP_WIN)
 #include <windows.h>
 #else
 // XXX add necessary include file for ftruncate (or equivalent)
 #endif
 #include "prthread.h"
 #include "private/pprio.h"
 #include "nsDiskCacheDevice.h"
 #include "nsDiskCacheEntry.h"
 #include "nsDiskCacheMap.h"
 #include "nsDiskCacheStreams.h"
 #include "nsDiskCache.h"
 #include "nsCacheService.h"
 #include "nsDeleteDir.h"
 #include "nsICacheVisitor.h"
 #include "nsReadableUtils.h"
 #include "nsIInputStream.h"
 #include "nsIOutputStream.h"
 #include "nsCRT.h"
 #include "nsCOMArray.h"
 #include "nsISimpleEnumerator.h"
 #include "nsThreadUtils.h"
 #include "mozilla/MemoryReporting.h"
 #include "mozilla/Telemetry.h"
 static const char DISK_CACHE_DEVICE_ID[] = { "disk" };
 using namespace mozilla;
 class nsDiskCacheDeviceDeactivateEntryEvent : public nsRunnable {
 public:
     nsDiskCacheDeviceDeactivateEntryEvent(nsDiskCacheDevice *device,
                                           nsCacheEntry * entry,
                                           nsDiskCacheBinding * binding)
         : mCanceled(false),
           mEntry(entry),
           mDevice(device),
           mBinding(binding)
     {
     }
     NS_IMETHOD Run()
     {
         nsCacheServiceAutoLock lock(LOCK_TELEM(NSDISKCACHEDEVICEDEACTIVATEENTRYEVENT_RUN));
 #ifdef PR_LOGGING
         CACHE_LOG_DEBUG(("nsDiskCacheDeviceDeactivateEntryEvent[%p]\n", this));
 #endif
         if (!mCanceled) {
             (void) mDevice->DeactivateEntry_Private(mEntry, mBinding);
         }
         return NS_OK;
     }
     void CancelEvent() { mCanceled = true; }
 private:
     bool mCanceled;
     nsCacheEntry *mEntry;
     nsDiskCacheDevice *mDevice;
     nsDiskCacheBinding *mBinding;
 };
 class nsEvictDiskCacheEntriesEvent : public nsRunnable {
 public:
     nsEvictDiskCacheEntriesEvent(nsDiskCacheDevice *device)
         : mDevice(device) {}
     NS_IMETHOD Run()
     {
         nsCacheServiceAutoLock lock(LOCK_TELEM(NSEVICTDISKCACHEENTRIESEVENT_RUN));
         mDevice->EvictDiskCacheEntries(mDevice->mCacheCapacity);
         return NS_OK;
     }
 private:
     nsDiskCacheDevice *mDevice;
 };
 /******************************************************************************
  *  nsDiskCacheEvictor
  *
  *  Helper class for nsDiskCacheDevice.
  *
  *****************************************************************************/
 class nsDiskCacheEvictor : public nsDiskCacheRecordVisitor
 {
 public:
     nsDiskCacheEvictor( nsDiskCacheMap *      cacheMap,
                         nsDiskCacheBindery *  cacheBindery,
                         uint32_t              targetSize,
                         const char *          clientID)
         : mCacheMap(cacheMap)
         , mBindery(cacheBindery)
         , mTargetSize(targetSize)
         , mClientID(clientID)
     {
         mClientIDSize = clientID ? strlen(clientID) : 0;
     }
     virtual int32_t  VisitRecord(nsDiskCacheRecord *  mapRecord);
 private:
         nsDiskCacheMap *     mCacheMap;
         nsDiskCacheBindery * mBindery;
         uint32_t             mTargetSize;
         const char *         mClientID;
         uint32_t             mClientIDSize;
 };
 int32_t
 nsDiskCacheEvictor::VisitRecord(nsDiskCacheRecord *  mapRecord)
 {
     if (mCacheMap->TotalSize() < mTargetSize)
         return kStopVisitingRecords;
     if (mClientID) {
         // we're just evicting records for a specific client
         nsDiskCacheEntry * diskEntry = mCacheMap->ReadDiskCacheEntry(mapRecord);
         if (!diskEntry)
             return kVisitNextRecord;  // XXX or delete record?
         // Compare clientID's without malloc
         if ((diskEntry->mKeySize <= mClientIDSize) ||
             (diskEntry->Key()[mClientIDSize] != ':') ||
             (memcmp(diskEntry->Key(), mClientID, mClientIDSize) != 0)) {
             return kVisitNextRecord;  // clientID doesn't match, skip it
         }
     }
     nsDiskCacheBinding * binding = mBindery->FindActiveBinding(mapRecord->HashNumber());
     if (binding) {
         // If the entry is pending deactivation, cancel deactivation and doom
         // the entry
         if (binding->mDeactivateEvent) {
             binding->mDeactivateEvent->CancelEvent();
             binding->mDeactivateEvent = nullptr;
         }
         // We are currently using this entry, so all we can do is doom it.
         // Since we're enumerating the records, we don't want to call
         // DeleteRecord when nsCacheService::DoomEntry() calls us back.
         binding->mDoomed = true;         // mark binding record as 'deleted'
         nsCacheService::DoomEntry(binding->mCacheEntry);
     } else {
         // entry not in use, just delete storage because we're enumerating the records
         (void) mCacheMap->DeleteStorage(mapRecord);
     }
     return kDeleteRecordAndContinue;  // this will REALLY delete the record
 }
 /******************************************************************************
  *  nsDiskCacheDeviceInfo
  *****************************************************************************/
 class nsDiskCacheDeviceInfo : public nsICacheDeviceInfo {
 public:
     NS_DECL_ISUPPORTS
     NS_DECL_NSICACHEDEVICEINFO
     nsDiskCacheDeviceInfo(nsDiskCacheDevice* device)
         :   mDevice(device)
     {
     }
     virtual ~nsDiskCacheDeviceInfo() {}
 private:
     nsDiskCacheDevice* mDevice;
 };
 NS_IMPL_ISUPPORTS(nsDiskCacheDeviceInfo, nsICacheDeviceInfo)
 /* readonly attribute string description; */
 NS_IMETHODIMP nsDiskCacheDeviceInfo::GetDescription(char ** aDescription)
 {
     NS_ENSURE_ARG_POINTER(aDescription);
     *aDescription = NS_strdup("Disk cache device");
     return *aDescription ? NS_OK : NS_ERROR_OUT_OF_MEMORY;
 }
 /* readonly attribute string usageReport; */
 NS_IMETHODIMP nsDiskCacheDeviceInfo::GetUsageReport(char ** usageReport)
 {
     NS_ENSURE_ARG_POINTER(usageReport);
     nsCString buffer;
     buffer.AssignLiteral("  <tr>\n"
                          "    <th>Cache Directory:</th>\n"
                          "    <td>");
     nsCOMPtr<nsIFile> cacheDir;
     nsAutoString path;
     mDevice->getCacheDirectory(getter_AddRefs(cacheDir));
     nsresult rv = cacheDir->GetPath(path);
     if (NS_SUCCEEDED(rv)) {
         AppendUTF16toUTF8(path, buffer);
     } else {
         buffer.AppendLiteral("directory unavailable");
     }
     buffer.AppendLiteral("</td>\n"
                          "  </tr>\n");
     *usageReport = ToNewCString(buffer);
     if (!*usageReport) return NS_ERROR_OUT_OF_MEMORY;
     return NS_OK;
 }
 /* readonly attribute unsigned long entryCount; */
 NS_IMETHODIMP nsDiskCacheDeviceInfo::GetEntryCount(uint32_t *aEntryCount)
 {
     NS_ENSURE_ARG_POINTER(aEntryCount);
     *aEntryCount = mDevice->getEntryCount();
     return NS_OK;
 }
 /* readonly attribute unsigned long totalSize; */
 NS_IMETHODIMP nsDiskCacheDeviceInfo::GetTotalSize(uint32_t *aTotalSize)
 {
     NS_ENSURE_ARG_POINTER(aTotalSize);
     // Returned unit's are in bytes
     *aTotalSize = mDevice->getCacheSize() * 1024;
     return NS_OK;
 }
 /* readonly attribute unsigned long maximumSize; */
 NS_IMETHODIMP nsDiskCacheDeviceInfo::GetMaximumSize(uint32_t *aMaximumSize)
 {
     NS_ENSURE_ARG_POINTER(aMaximumSize);
     // Returned unit's are in bytes
     *aMaximumSize = mDevice->getCacheCapacity() * 1024;
     return NS_OK;
 }
 /******************************************************************************
  *  nsDiskCache
  *****************************************************************************/
 /**
  *  nsDiskCache::Hash(const char * key, PLDHashNumber initval)
  *
  *  See http://burtleburtle.net/bob/hash/evahash.html for more information
  *  about this hash function.
  *
  *  This algorithm of this method implies nsDiskCacheRecords will be stored
  *  in a certain order on disk.  If the algorithm changes, existing cache
  *  map files may become invalid, and therefore the kCurrentVersion needs
  *  to be revised.
  */
 static inline void hashmix(uint32_t& a, uint32_t& b, uint32_t& c)
 {
   a -= b; a -= c; a ^= (c>>13);
   b -= c; b -= a; b ^= (a<<8);
   c -= a; c -= b; c ^= (b>>13);
   a -= b; a -= c; a ^= (c>>12);
   b -= c; b -= a; b ^= (a<<16);
   c -= a; c -= b; c ^= (b>>5);
   a -= b; a -= c; a ^= (c>>3);
   b -= c; b -= a; b ^= (a<<10);
   c -= a; c -= b; c ^= (b>>15);
 }
 PLDHashNumber
 nsDiskCache::Hash(const char * key, PLDHashNumber initval)
 {
   const uint8_t *k = reinterpret_cast<const uint8_t*>(key);
   uint32_t a, b, c, len, length;
   length = strlen(key);
   /* Set up the internal state */
   len = length;
   a = b = 0x9e3779b9;  /* the golden ratio; an arbitrary value */
   c = initval;         /* variable initialization of internal state */
   /*---------------------------------------- handle most of the key */
   while (len >= 12)
   {
     a += k[0] + (uint32_t(k[1])<<8) + (uint32_t(k[2])<<16) + (uint32_t(k[3])<<24);
     b += k[4] + (uint32_t(k[5])<<8) + (uint32_t(k[6])<<16) + (uint32_t(k[7])<<24);
     c += k[8] + (uint32_t(k[9])<<8) + (uint32_t(k[10])<<16) + (uint32_t(k[11])<<24);
     hashmix(a, b, c);
     k += 12; len -= 12;
   }
   /*------------------------------------- handle the last 11 bytes */
   c += length;
   switch(len) {              /* all the case statements fall through */
     case 11: c += (uint32_t(k[10])<<24);
     case 10: c += (uint32_t(k[9])<<16);
     case 9 : c += (uint32_t(k[8])<<8);
     /* the low-order byte of c is reserved for the length */
     case 8 : b += (uint32_t(k[7])<<24);
     case 7 : b += (uint32_t(k[6])<<16);
     case 6 : b += (uint32_t(k[5])<<8);
     case 5 : b += k[4];
     case 4 : a += (uint32_t(k[3])<<24);
     case 3 : a += (uint32_t(k[2])<<16);
     case 2 : a += (uint32_t(k[1])<<8);
     case 1 : a += k[0];
     /* case 0: nothing left to add */
   }
   hashmix(a, b, c);
   return c;
 }
 nsresult
 nsDiskCache::Truncate(PRFileDesc *  fd, uint32_t  newEOF)
 {
     // use modified SetEOF from nsFileStreams::SetEOF()
 #if defined(XP_UNIX)
     if (ftruncate(PR_FileDesc2NativeHandle(fd), newEOF) != 0) {
         NS_ERROR("ftruncate failed");
         return NS_ERROR_FAILURE;
     }
 #elif defined(XP_WIN)
     int32_t cnt = PR_Seek(fd, newEOF, PR_SEEK_SET);
     if (cnt == -1)  return NS_ERROR_FAILURE;
     if (!SetEndOfFile((HANDLE) PR_FileDesc2NativeHandle(fd))) {
         NS_ERROR("SetEndOfFile failed");
         return NS_ERROR_FAILURE;
     }
 #else
     // add implementations for other platforms here
 #endif
     return NS_OK;
 }
 /******************************************************************************
  *  nsDiskCacheDevice
  *****************************************************************************/
 nsDiskCacheDevice::nsDiskCacheDevice()
     : mCacheCapacity(0)
     , mMaxEntrySize(-1) // -1 means "no limit"
     , mInitialized(false)
     , mClearingDiskCache(false)
 {
 }
 nsDiskCacheDevice::~nsDiskCacheDevice()
 {
     Shutdown();
 }
 /**
  *  methods of nsCacheDevice
  */
 nsresult
 nsDiskCacheDevice::Init()
 {
     nsresult rv;
     if (Initialized()) {
         NS_ERROR("Disk cache already initialized!");
         return NS_ERROR_UNEXPECTED;
     }
     if (!mCacheDirectory)
         return NS_ERROR_FAILURE;
     rv = mBindery.Init();
     if (NS_FAILED(rv))
         return rv;
     nsDeleteDir::RemoveOldTrashes(mCacheDirectory);
     // Open Disk Cache
     rv = OpenDiskCache();
     if (NS_FAILED(rv)) {
         (void) mCacheMap.Close(false);
         return rv;
     }
     mInitialized = true;
     return NS_OK;
 }
 /**
  *  NOTE: called while holding the cache service lock
  */
 nsresult
 nsDiskCacheDevice::Shutdown()
 {
     nsCacheService::AssertOwnsLock();
     nsresult rv = Shutdown_Private(true);
     if (NS_FAILED(rv))
         return rv;
     return NS_OK;
 }
 nsresult
 nsDiskCacheDevice::Shutdown_Private(bool    flush)
 {
     CACHE_LOG_DEBUG(("CACHE: disk Shutdown_Private [%u]\n", flush));
     if (Initialized()) {
         // check cache limits in case we need to evict.
         EvictDiskCacheEntries(mCacheCapacity);
         // At this point there may be a number of pending cache-requests on the
         // cache-io thread. Wait for all these to run before we wipe out our
         // datastructures (see bug #620660)
         (void) nsCacheService::SyncWithCacheIOThread();
         // write out persistent information about the cache.
         (void) mCacheMap.Close(flush);
         mBindery.Reset();
         mInitialized = false;
     }
     return NS_OK;
 }
 const char *
 nsDiskCacheDevice::GetDeviceID()
 {
     return DISK_CACHE_DEVICE_ID;
 }
 /**
  *  FindEntry -
  *
  *      cases:  key not in disk cache, hash number free
  *              key not in disk cache, hash number used
  *              key in disk cache
  *
  *  NOTE: called while holding the cache service lock
  */
 nsCacheEntry *
 nsDiskCacheDevice::FindEntry(nsCString * key, bool *collision)
 {
     Telemetry::AutoTimer<Telemetry::CACHE_DISK_SEARCH_2> timer;
     if (!Initialized())  return nullptr;  // NS_ERROR_NOT_INITIALIZED
     if (mClearingDiskCache)  return nullptr;
     nsDiskCacheRecord       record;
     nsDiskCacheBinding *    binding = nullptr;
     PLDHashNumber           hashNumber = nsDiskCache::Hash(key->get());
     *collision = false;
     binding = mBindery.FindActiveBinding(hashNumber);
     if (binding && !binding->mCacheEntry->Key()->Equals(*key)) {
         *collision = true;
         return nullptr;
     } else if (binding && binding->mDeactivateEvent) {
         binding->mDeactivateEvent->CancelEvent();
         binding->mDeactivateEvent = nullptr;
         CACHE_LOG_DEBUG(("CACHE: reusing deactivated entry %p " \
                          "req-key=%s  entry-key=%s\n",
                          binding->mCacheEntry, key, binding->mCacheEntry->Key()));
         return binding->mCacheEntry; // just return this one, observing that
                                      // FindActiveBinding() does not return
                                      // bindings to doomed entries
     }
     binding = nullptr;
     // lookup hash number in cache map
     nsresult rv = mCacheMap.FindRecord(hashNumber, &record);
     if (NS_FAILED(rv))  return nullptr;  // XXX log error?
     nsDiskCacheEntry * diskEntry = mCacheMap.ReadDiskCacheEntry(&record);
     if (!diskEntry) return nullptr;
     // compare key to be sure
     if (!key->Equals(diskEntry->Key())) {
         *collision = true;
         return nullptr;
     }
     nsCacheEntry * entry = diskEntry->CreateCacheEntry(this);
     if (entry) {
         binding = mBindery.CreateBinding(entry, &record);
         if (!binding) {
             delete entry;
             entry = nullptr;
         }
     }
     if (!entry) {
       (void) mCacheMap.DeleteStorage(&record);
       (void) mCacheMap.DeleteRecord(&record);
     }
     return entry;
 }
 /**
  *  NOTE: called while holding the cache service lock
  */
 nsresult
 nsDiskCacheDevice::DeactivateEntry(nsCacheEntry * entry)
 {
     nsDiskCacheBinding * binding = GetCacheEntryBinding(entry);
     if (!IsValidBinding(binding))
         return NS_ERROR_UNEXPECTED;
     CACHE_LOG_DEBUG(("CACHE: disk DeactivateEntry [%p %x]\n",
         entry, binding->mRecord.HashNumber()));
     nsDiskCacheDeviceDeactivateEntryEvent *event =
         new nsDiskCacheDeviceDeactivateEntryEvent(this, entry, binding);
     // ensure we can cancel the event via the binding later if necessary
     binding->mDeactivateEvent = event;
     DebugOnly<nsresult> rv = nsCacheService::DispatchToCacheIOThread(event);
     NS_ASSERTION(NS_SUCCEEDED(rv), "DeactivateEntry: Failed dispatching "
                                    "deactivation event");
     return NS_OK;
 }
 /**
  *  NOTE: called while holding the cache service lock
  */
 nsresult
 nsDiskCacheDevice::DeactivateEntry_Private(nsCacheEntry * entry,
                                            nsDiskCacheBinding * binding)
 {
     nsresult rv = NS_OK;
     if (entry->IsDoomed()) {
         // delete data, entry, record from disk for entry
         rv = mCacheMap.DeleteStorage(&binding->mRecord);
     } else {
         // save stuff to disk for entry
         rv = mCacheMap.WriteDiskCacheEntry(binding);
         if (NS_FAILED(rv)) {
             // clean up as best we can
             (void) mCacheMap.DeleteStorage(&binding->mRecord);
             (void) mCacheMap.DeleteRecord(&binding->mRecord);
             binding->mDoomed = true; // record is no longer in cache map
         }
     }
     mBindery.RemoveBinding(binding); // extract binding from collision detection stuff
     delete entry;   // which will release binding
     return rv;
 }
 /**
  * BindEntry()
  *      no hash number collision -> no problem
  *      collision
  *          record not active -> evict, no problem
  *          record is active
  *              record is already doomed -> record shouldn't have been in map, no problem
  *              record is not doomed -> doom, and replace record in map
  *
  *              walk matching hashnumber list to find lowest generation number
  *              take generation number from other (data/meta) location,
  *                  or walk active list
  *
  *  NOTE: called while holding the cache service lock
  */
 nsresult
 nsDiskCacheDevice::BindEntry(nsCacheEntry * entry)
 {
     if (!Initialized())  return  NS_ERROR_NOT_INITIALIZED;
     if (mClearingDiskCache)  return NS_ERROR_NOT_AVAILABLE;
     nsresult rv = NS_OK;
     nsDiskCacheRecord record, oldRecord;
     nsDiskCacheBinding *binding;
     PLDHashNumber hashNumber = nsDiskCache::Hash(entry->Key()->get());
     // Find out if there is already an active binding for this hash. If yes it
     // should have another key since BindEntry() shouldn't be called twice for
     // the same entry. Doom the old entry, the new one will get another
     // generation number so files won't collide.
     binding = mBindery.FindActiveBinding(hashNumber);
     if (binding) {
         NS_ASSERTION(!binding->mCacheEntry->Key()->Equals(*entry->Key()),
                      "BindEntry called for already bound entry!");
         // If the entry is pending deactivation, cancel deactivation
         if (binding->mDeactivateEvent) {
             binding->mDeactivateEvent->CancelEvent();
             binding->mDeactivateEvent = nullptr;
         }
         nsCacheService::DoomEntry(binding->mCacheEntry);
         binding = nullptr;
     }
     // Lookup hash number in cache map. There can be a colliding inactive entry.
     // See bug #321361 comment 21 for the scenario. If there is such entry,
     // delete it.
     rv = mCacheMap.FindRecord(hashNumber, &record);
     if (NS_SUCCEEDED(rv)) {
         nsDiskCacheEntry * diskEntry = mCacheMap.ReadDiskCacheEntry(&record);
         if (diskEntry) {
             // compare key to be sure
             if (!entry->Key()->Equals(diskEntry->Key())) {
                 mCacheMap.DeleteStorage(&record);
                 rv = mCacheMap.DeleteRecord(&record);
                 if (NS_FAILED(rv))  return rv;
             }
         }
         record = nsDiskCacheRecord();
     }
     // create a new record for this entry
     record.SetHashNumber(nsDiskCache::Hash(entry->Key()->get()));
     record.SetEvictionRank(ULONG_MAX - SecondsFromPRTime(PR_Now()));
     CACHE_LOG_DEBUG(("CACHE: disk BindEntry [%p %x]\n",
         entry, record.HashNumber()));
     if (!entry->IsDoomed()) {
         // if entry isn't doomed, add it to the cache map
         rv = mCacheMap.AddRecord(&record, &oldRecord); // deletes old record, if any
         if (NS_FAILED(rv))  return rv;
         uint32_t    oldHashNumber = oldRecord.HashNumber();
         if (oldHashNumber) {
             // gotta evict this one first
             nsDiskCacheBinding * oldBinding = mBindery.FindActiveBinding(oldHashNumber);
             if (oldBinding) {
                 // XXX if debug : compare keys for hashNumber collision
                 if (!oldBinding->mCacheEntry->IsDoomed()) {
                     // If the old entry is pending deactivation, cancel deactivation
                     if (oldBinding->mDeactivateEvent) {
                         oldBinding->mDeactivateEvent->CancelEvent();
                         oldBinding->mDeactivateEvent = nullptr;
                     }
                 // we've got a live one!
                     nsCacheService::DoomEntry(oldBinding->mCacheEntry);
                     // storage will be delete when oldBinding->mCacheEntry is Deactivated
                 }
             } else {
                 // delete storage
                 // XXX if debug : compare keys for hashNumber collision
                 rv = mCacheMap.DeleteStorage(&oldRecord);
                 if (NS_FAILED(rv))  return rv;  // XXX delete record we just added?
             }
         }
     }
     // Make sure this entry has its associated nsDiskCacheBinding attached.
     binding = mBindery.CreateBinding(entry, &record);
     NS_ASSERTION(binding, "nsDiskCacheDevice::BindEntry");
     if (!binding) return NS_ERROR_OUT_OF_MEMORY;
     NS_ASSERTION(binding->mRecord.ValidRecord(), "bad cache map record");
     return NS_OK;
 }
 /**
  *  NOTE: called while holding the cache service lock
  */
 void
 nsDiskCacheDevice::DoomEntry(nsCacheEntry * entry)
 {
     CACHE_LOG_DEBUG(("CACHE: disk DoomEntry [%p]\n", entry));
     nsDiskCacheBinding * binding = GetCacheEntryBinding(entry);
     NS_ASSERTION(binding, "DoomEntry: binding == nullptr");
     if (!binding)
         return;
     if (!binding->mDoomed) {
         // so it can't be seen by FindEntry() ever again.
 #ifdef DEBUG
         nsresult rv =
 #endif
             mCacheMap.DeleteRecord(&binding->mRecord);
         NS_ASSERTION(NS_SUCCEEDED(rv),"DeleteRecord failed.");
         binding->mDoomed = true; // record in no longer in cache map
     }
 }
 /**
  *  NOTE: called while holding the cache service lock
  */
 nsresult
 nsDiskCacheDevice::OpenInputStreamForEntry(nsCacheEntry *      entry,
                                            nsCacheAccessMode   mode,
                                            uint32_t            offset,
                                            nsIInputStream **   result)
 {
     CACHE_LOG_DEBUG(("CACHE: disk OpenInputStreamForEntry [%p %x %u]\n",
         entry, mode, offset));
     NS_ENSURE_ARG_POINTER(entry);
     NS_ENSURE_ARG_POINTER(result);
     nsresult             rv;
     nsDiskCacheBinding * binding = GetCacheEntryBinding(entry);
     if (!IsValidBinding(binding))
         return NS_ERROR_UNEXPECTED;
     NS_ASSERTION(binding->mCacheEntry == entry, "binding & entry don't point to each other");
     rv = binding->EnsureStreamIO();
     if (NS_FAILED(rv)) return rv;
     return binding->mStreamIO->GetInputStream(offset, result);
 }
 /**
  *  NOTE: called while holding the cache service lock
  */
 nsresult
 nsDiskCacheDevice::OpenOutputStreamForEntry(nsCacheEntry *      entry,
                                             nsCacheAccessMode   mode,
                                             uint32_t            offset,
                                             nsIOutputStream **  result)
 {
     CACHE_LOG_DEBUG(("CACHE: disk OpenOutputStreamForEntry [%p %x %u]\n",
         entry, mode, offset));
     NS_ENSURE_ARG_POINTER(entry);
     NS_ENSURE_ARG_POINTER(result);
     nsresult             rv;
     nsDiskCacheBinding * binding = GetCacheEntryBinding(entry);
     if (!IsValidBinding(binding))
         return NS_ERROR_UNEXPECTED;
     NS_ASSERTION(binding->mCacheEntry == entry, "binding & entry don't point to each other");
     rv = binding->EnsureStreamIO();
     if (NS_FAILED(rv)) return rv;
     return binding->mStreamIO->GetOutputStream(offset, result);
 }
 /**
  *  NOTE: called while holding the cache service lock
  */
 nsresult
 nsDiskCacheDevice::GetFileForEntry(nsCacheEntry *    entry,
                                    nsIFile **        result)
 {
     NS_ENSURE_ARG_POINTER(result);
     *result = nullptr;
     nsresult             rv;
     nsDiskCacheBinding * binding = GetCacheEntryBinding(entry);
     if (!IsValidBinding(binding))
         return NS_ERROR_UNEXPECTED;
     // check/set binding->mRecord for separate file, sync w/mCacheMap
     if (binding->mRecord.DataLocationInitialized()) {
         if (binding->mRecord.DataFile() != 0)
             return NS_ERROR_NOT_AVAILABLE;  // data not stored as separate file
         NS_ASSERTION(binding->mRecord.DataFileGeneration() == binding->mGeneration, "error generations out of sync");
     } else {
         binding->mRecord.SetDataFileGeneration(binding->mGeneration);
         binding->mRecord.SetDataFileSize(0);    // 1k minimum
         if (!binding->mDoomed) {
             // record stored in cache map, so update it
             rv = mCacheMap.UpdateRecord(&binding->mRecord);
             if (NS_FAILED(rv))  return rv;
         }
     }
     nsCOMPtr<nsIFile>  file;
     rv = mCacheMap.GetFileForDiskCacheRecord(&binding->mRecord,
                                              nsDiskCache::kData,
                                              false,
                                              getter_AddRefs(file));
     if (NS_FAILED(rv))  return rv;
     NS_IF_ADDREF(*result = file);
     return NS_OK;
 }
 /**
  *  This routine will get called every time an open descriptor is written to.
  *
  *  NOTE: called while holding the cache service lock
  */
 nsresult
 nsDiskCacheDevice::OnDataSizeChange(nsCacheEntry * entry, int32_t deltaSize)
 {
     CACHE_LOG_DEBUG(("CACHE: disk OnDataSizeChange [%p %d]\n",
         entry, deltaSize));
     // If passed a negative value, then there's nothing to do.
     if (deltaSize < 0)
         return NS_OK;
     nsDiskCacheBinding * binding = GetCacheEntryBinding(entry);
     if (!IsValidBinding(binding))
         return NS_ERROR_UNEXPECTED;
     NS_ASSERTION(binding->mRecord.ValidRecord(), "bad record");
     uint32_t  newSize = entry->DataSize() + deltaSize;
     uint32_t  newSizeK =  ((newSize + 0x3FF) >> 10);
     // If the new size is larger than max. file size or larger than
     // 1/8 the cache capacity (which is in KiB's), doom the entry and abort.
     if (EntryIsTooBig(newSize)) {
 #ifdef DEBUG
         nsresult rv =
 #endif
             nsCacheService::DoomEntry(entry);
         NS_ASSERTION(NS_SUCCEEDED(rv),"DoomEntry() failed.");
         return NS_ERROR_ABORT;
     }
     uint32_t  sizeK = ((entry->DataSize() + 0x03FF) >> 10); // round up to next 1k
     // In total count we ignore anything over kMaxDataSizeK (bug #651100), so
     // the target capacity should be calculated the same way.
     if (sizeK > kMaxDataSizeK) sizeK = kMaxDataSizeK;
     if (newSizeK > kMaxDataSizeK) newSizeK = kMaxDataSizeK;
     // pre-evict entries to make space for new data
     uint32_t  targetCapacity = mCacheCapacity > (newSizeK - sizeK)
                              ? mCacheCapacity - (newSizeK - sizeK)
                              : 0;
     EvictDiskCacheEntries(targetCapacity);
     return NS_OK;
 }
 /******************************************************************************
  *  EntryInfoVisitor
  *****************************************************************************/
 class EntryInfoVisitor : public nsDiskCacheRecordVisitor
 {
 public:
     EntryInfoVisitor(nsDiskCacheMap *    cacheMap,
                      nsICacheVisitor *   visitor)
         : mCacheMap(cacheMap)
         , mVisitor(visitor)
     {}
     virtual int32_t  VisitRecord(nsDiskCacheRecord *  mapRecord)
     {
         // XXX optimization: do we have this record in memory?
         // read in the entry (metadata)
         nsDiskCacheEntry * diskEntry = mCacheMap->ReadDiskCacheEntry(mapRecord);
         if (!diskEntry) {
             return kVisitNextRecord;
         }
         // create nsICacheEntryInfo
         nsDiskCacheEntryInfo * entryInfo = new nsDiskCacheEntryInfo(DISK_CACHE_DEVICE_ID, diskEntry);
         if (!entryInfo) {
             return kStopVisitingRecords;
         }
         nsCOMPtr<nsICacheEntryInfo> ref(entryInfo);
         bool    keepGoing;
         (void)mVisitor->VisitEntry(DISK_CACHE_DEVICE_ID, entryInfo, &keepGoing);
         return keepGoing ? kVisitNextRecord : kStopVisitingRecords;
     }
 private:
         nsDiskCacheMap *    mCacheMap;
         nsICacheVisitor *   mVisitor;
 };
 nsresult
 nsDiskCacheDevice::Visit(nsICacheVisitor * visitor)
 {
     if (!Initialized())  return NS_ERROR_NOT_INITIALIZED;
     nsDiskCacheDeviceInfo* deviceInfo = new nsDiskCacheDeviceInfo(this);
     nsCOMPtr<nsICacheDeviceInfo> ref(deviceInfo);
     bool keepGoing;
     nsresult rv = visitor->VisitDevice(DISK_CACHE_DEVICE_ID, deviceInfo, &keepGoing);
     if (NS_FAILED(rv)) return rv;
     if (keepGoing) {
         EntryInfoVisitor  infoVisitor(&mCacheMap, visitor);
         return mCacheMap.VisitRecords(&infoVisitor);
     }
     return NS_OK;
 }
 // Max allowed size for an entry is currently MIN(mMaxEntrySize, 1/8 CacheCapacity)
 bool
 nsDiskCacheDevice::EntryIsTooBig(int64_t entrySize)
 {
     if (mMaxEntrySize == -1) // no limit
         return entrySize > (static_cast<int64_t>(mCacheCapacity) * 1024 / 8);
     else
         return entrySize > mMaxEntrySize ||
                entrySize > (static_cast<int64_t>(mCacheCapacity) * 1024 / 8);
 }
 nsresult
 nsDiskCacheDevice::EvictEntries(const char * clientID)
 {
     CACHE_LOG_DEBUG(("CACHE: disk EvictEntries [%s]\n", clientID));
     if (!Initialized())  return NS_ERROR_NOT_INITIALIZED;
     nsresult  rv;
     if (clientID == nullptr) {
         // we're clearing the entire disk cache
         rv = ClearDiskCache();
         if (rv != NS_ERROR_CACHE_IN_USE)
             return rv;
     }
     nsDiskCacheEvictor  evictor(&mCacheMap, &mBindery, 0, clientID);
     rv = mCacheMap.VisitRecords(&evictor);
     if (clientID == nullptr)     // we tried to clear the entire cache
         rv = mCacheMap.Trim(); // so trim cache block files (if possible)
     return rv;
 }
 /**
  *  private methods
  */
 nsresult
 nsDiskCacheDevice::OpenDiskCache()
 {
     Telemetry::AutoTimer<Telemetry::NETWORK_DISK_CACHE_OPEN> timer;
     // if we don't have a cache directory, create one and open it
     bool exists;
     nsresult rv = mCacheDirectory->Exists(&exists);
     if (NS_FAILED(rv))
         return rv;
     if (exists) {
         // Try opening cache map file.
         nsDiskCache::CorruptCacheInfo corruptInfo;
         rv = mCacheMap.Open(mCacheDirectory, &corruptInfo, true);
         if (NS_SUCCEEDED(rv)) {
             Telemetry::Accumulate(Telemetry::DISK_CACHE_CORRUPT_DETAILS,
                                   corruptInfo);
         } else if (rv == NS_ERROR_ALREADY_INITIALIZED) {
           NS_WARNING("nsDiskCacheDevice::OpenDiskCache: already open!");
         } else {
             // Consider cache corrupt: delete it
             Telemetry::Accumulate(Telemetry::DISK_CACHE_CORRUPT_DETAILS,
                                   corruptInfo);
             // delay delete by 1 minute to avoid IO thrash at startup
             rv = nsDeleteDir::DeleteDir(mCacheDirectory, true, 60000);
             if (NS_FAILED(rv))
                 return rv;
             exists = false;
         }
     }
     // if we don't have a cache directory, create one and open it
     if (!exists) {
         nsCacheService::MarkStartingFresh();
         rv = mCacheDirectory->Create(nsIFile::DIRECTORY_TYPE, 0777);
         CACHE_LOG_PATH(PR_LOG_ALWAYS, "\ncreate cache directory: %s\n", mCacheDirectory);
         CACHE_LOG_ALWAYS(("mCacheDirectory->Create() = %x\n", rv));
         if (NS_FAILED(rv))
             return rv;
         // reopen the cache map
         nsDiskCache::CorruptCacheInfo corruptInfo;
         rv = mCacheMap.Open(mCacheDirectory, &corruptInfo, false);
         if (NS_FAILED(rv))
             return rv;
     }
     return NS_OK;
 }
 nsresult
 nsDiskCacheDevice::ClearDiskCache()
 {
     if (mBindery.ActiveBindings())
         return NS_ERROR_CACHE_IN_USE;
     mClearingDiskCache = true;
     nsresult rv = Shutdown_Private(false);  // false: don't bother flushing
     if (NS_FAILED(rv))
         return rv;
     mClearingDiskCache = false;
     // If the disk cache directory is already gone, then it's not an error if
     // we fail to delete it ;-)
     rv = nsDeleteDir::DeleteDir(mCacheDirectory, true);
     if (NS_FAILED(rv) && rv != NS_ERROR_FILE_TARGET_DOES_NOT_EXIST)
         return rv;
     return Init();
 }
 nsresult
 nsDiskCacheDevice::EvictDiskCacheEntries(uint32_t  targetCapacity)
 {
     CACHE_LOG_DEBUG(("CACHE: disk EvictDiskCacheEntries [%u]\n",
         targetCapacity));
     NS_ASSERTION(targetCapacity > 0, "oops");
     if (mCacheMap.TotalSize() < targetCapacity)
         return NS_OK;
     // targetCapacity is in KiB's
     nsDiskCacheEvictor  evictor(&mCacheMap, &mBindery, targetCapacity, nullptr);
     return mCacheMap.EvictRecords(&evictor);
 }
 /**
  *  methods for prefs
  */
 void
 nsDiskCacheDevice::SetCacheParentDirectory(nsIFile * parentDir)
 {
     nsresult rv;
     bool    exists;
     if (Initialized()) {
         NS_ASSERTION(false, "Cannot switch cache directory when initialized");
         return;
     }
     if (!parentDir) {
         mCacheDirectory = nullptr;
         return;
     }
     // ensure parent directory exists
     rv = parentDir->Exists(&exists);
     if (NS_SUCCEEDED(rv) && !exists)
         rv = parentDir->Create(nsIFile::DIRECTORY_TYPE, 0700);
     if (NS_FAILED(rv))  return;
     // ensure cache directory exists
     nsCOMPtr<nsIFile> directory;
     rv = parentDir->Clone(getter_AddRefs(directory));
     if (NS_FAILED(rv))  return;
     rv = directory->AppendNative(NS_LITERAL_CSTRING("Cache"));
     if (NS_FAILED(rv))  return;
     mCacheDirectory = do_QueryInterface(directory);
 }
 void
 nsDiskCacheDevice::getCacheDirectory(nsIFile ** result)
 {
     *result = mCacheDirectory;
     NS_IF_ADDREF(*result);
 }
 /**
  *  NOTE: called while holding the cache service lock
  */
 void
 nsDiskCacheDevice::SetCapacity(uint32_t  capacity)
 {
     // Units are KiB's
     mCacheCapacity = capacity;
     if (Initialized()) {
         if (NS_IsMainThread()) {
             // Do not evict entries on the main thread
             nsCacheService::DispatchToCacheIOThread(
                 new nsEvictDiskCacheEntriesEvent(this));
         } else {
             // start evicting entries if the new size is smaller!
             EvictDiskCacheEntries(mCacheCapacity);
         }
     }
     // Let cache map know of the new capacity
     mCacheMap.NotifyCapacityChange(capacity);
 }
 uint32_t nsDiskCacheDevice::getCacheCapacity()
 {
     return mCacheCapacity;
 }
 uint32_t nsDiskCacheDevice::getCacheSize()
 {
     return mCacheMap.TotalSize();
 }
 uint32_t nsDiskCacheDevice::getEntryCount()
 {
     return mCacheMap.EntryCount();
 }
 void
 nsDiskCacheDevice::SetMaxEntrySize(int32_t maxSizeInKilobytes)
 {
     // Internal units are bytes. Changing this only takes effect *after* the
     // change and has no consequences for existing cache-entries
     if (maxSizeInKilobytes >= 0)
         mMaxEntrySize = maxSizeInKilobytes * 1024;
     else
         mMaxEntrySize = -1;
 }
 size_t
 nsDiskCacheDevice::SizeOfIncludingThis(MallocSizeOf aMallocSizeOf)
 {
     size_t usage = aMallocSizeOf(this);
     usage += mCacheMap.SizeOfExcludingThis(aMallocSizeOf);
     usage += mBindery.SizeOfExcludingThis(aMallocSizeOf);
     return usage;
 }

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netwerk/cache/nsDiskCacheDevice.cpp@6474c204b198 (annotated)

netwerk/cache/nsDiskCacheDevice.cpp