dom/cache/QuotaClient.cpp
author Gregory Szorc <gps@mozilla.com>
Thu, 09 Nov 2017 22:26:26 -0800
changeset 391814 1cd169ff8a0dbb2ea7d50b4275472ca9298765b3
parent 386798 efe85265a82ad64e2e82128f245a6281222a9a28
child 391979 c40ecf4fefee1bcb83c8fbd1c0ff7b816c46e590
permissions -rw-r--r--
Bug 1416052 - Remove comment filtering; r=nalexander The auto-generated make file that we include (and the `mach environment` output that we included before that) should not contain comment lines. I think it is safe to remove the code that filters them out. It is possible a multi-line value in mozconfigs could contain lines looking like comments and this may cause problems. I'm inclined to believe that this scenario doesn't exist. If someone complains and we need to bring back support, we could certainly do that. MozReview-Commit-ID: 8kKw91HH4ms

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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 "mozilla/dom/cache/QuotaClient.h"

#include "mozilla/dom/cache/Manager.h"
#include "mozilla/dom/quota/QuotaManager.h"
#include "mozilla/dom/quota/UsageInfo.h"
#include "mozilla/ipc/BackgroundParent.h"
#include "nsIFile.h"
#include "nsISimpleEnumerator.h"
#include "nsThreadUtils.h"

namespace {

using mozilla::Atomic;
using mozilla::dom::ContentParentId;
using mozilla::dom::cache::DirPaddingFile;
using mozilla::dom::cache::Manager;
using mozilla::dom::cache::QuotaInfo;
using mozilla::dom::quota::AssertIsOnIOThread;
using mozilla::dom::quota::Client;
using mozilla::dom::quota::PersistenceType;
using mozilla::dom::quota::QuotaManager;
using mozilla::dom::quota::UsageInfo;
using mozilla::ipc::AssertIsOnBackgroundThread;
using mozilla::MutexAutoLock;
using mozilla::Unused;

static nsresult
GetBodyUsage(nsIFile* aDir, const Atomic<bool>& aCanceled,
             UsageInfo* aUsageInfo)
{
  AssertIsOnIOThread();

  nsCOMPtr<nsISimpleEnumerator> entries;
  nsresult rv = aDir->GetDirectoryEntries(getter_AddRefs(entries));
  if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }

  bool hasMore;
  while (NS_SUCCEEDED(rv = entries->HasMoreElements(&hasMore)) && hasMore &&
         !aCanceled) {
    nsCOMPtr<nsISupports> entry;
    rv = entries->GetNext(getter_AddRefs(entry));
    if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }

    nsCOMPtr<nsIFile> file = do_QueryInterface(entry);

    bool isDir;
    rv = file->IsDirectory(&isDir);
    if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }

    if (isDir) {
      rv = GetBodyUsage(file, aCanceled, aUsageInfo);
      if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
      continue;
    }

    int64_t fileSize;
    rv = file->GetFileSize(&fileSize);
    if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
    MOZ_DIAGNOSTIC_ASSERT(fileSize >= 0);

    aUsageInfo->AppendToFileUsage(fileSize);
  }

  return NS_OK;
}

static nsresult
LockedGetPaddingSizeFromDB(nsIFile* aDir, const nsACString& aGroup,
                           const nsACString& aOrigin, int64_t* aPaddingSizeOut)
{
  MOZ_DIAGNOSTIC_ASSERT(aDir);
  MOZ_DIAGNOSTIC_ASSERT(aPaddingSizeOut);

  *aPaddingSizeOut = 0;

  nsCOMPtr<mozIStorageConnection> conn;
  QuotaInfo quotaInfo;
  quotaInfo.mGroup = aGroup;
  quotaInfo.mOrigin = aOrigin;
  nsresult rv = mozilla::dom::cache::
                OpenDBConnection(quotaInfo, aDir, getter_AddRefs(conn));
  if (rv == NS_ERROR_FILE_NOT_FOUND ||
      rv == NS_ERROR_FILE_TARGET_DOES_NOT_EXIST) {
    // Return NS_OK with size = 0 if both the db and padding file don't exist.
    // There is no other way to get the overall padding size of an origin.
    return NS_OK;
  }
  if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }

  int64_t paddingSize = 0;
  rv = mozilla::dom::cache::
       LockedDirectoryPaddingRestore(aDir, conn, /* aMustRestore */ false,
                                     &paddingSize);
  if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }

  *aPaddingSizeOut = paddingSize;

  return rv;
}

class CacheQuotaClient final : public Client
{
  static CacheQuotaClient* sInstance;

public:
  CacheQuotaClient()
  : mDirPaddingFileMutex("DOMCacheQuotaClient.mDirPaddingFileMutex")
  {
    AssertIsOnBackgroundThread();
    MOZ_DIAGNOSTIC_ASSERT(!sInstance);
    sInstance = this;
  }

  static CacheQuotaClient*
  Get()
  {
    MOZ_DIAGNOSTIC_ASSERT(sInstance);
    return sInstance;
  }

  virtual Type
  GetType() override
  {
    return DOMCACHE;
  }

  virtual nsresult
  InitOrigin(PersistenceType aPersistenceType, const nsACString& aGroup,
             const nsACString& aOrigin, const AtomicBool& aCanceled,
             UsageInfo* aUsageInfo) override
  {
    AssertIsOnIOThread();

    // The QuotaManager passes a nullptr UsageInfo if there is no quota being
    // enforced against the origin.
    if (!aUsageInfo) {
      return NS_OK;
    }

    return GetUsageForOrigin(aPersistenceType, aGroup, aOrigin, aCanceled,
                             aUsageInfo);
  }

  virtual nsresult
  GetUsageForOrigin(PersistenceType aPersistenceType, const nsACString& aGroup,
                    const nsACString& aOrigin, const AtomicBool& aCanceled,
                    UsageInfo* aUsageInfo) override
  {
    AssertIsOnIOThread();
    MOZ_DIAGNOSTIC_ASSERT(aUsageInfo);

    QuotaManager* qm = QuotaManager::Get();
    MOZ_DIAGNOSTIC_ASSERT(qm);

    nsCOMPtr<nsIFile> dir;
    nsresult rv = qm->GetDirectoryForOrigin(aPersistenceType, aOrigin,
                                            getter_AddRefs(dir));
    if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }

    rv = dir->Append(NS_LITERAL_STRING(DOMCACHE_DIRECTORY_NAME));
    if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }

    int64_t paddingSize = 0;
    {
      // If the tempoary file still exists after locking, it means the previous
      // action fails, so restore the padding file.
      MutexAutoLock lock(mDirPaddingFileMutex);

      if (mozilla::dom::cache::
          DirectoryPaddingFileExists(dir, DirPaddingFile::TMP_FILE) ||
          NS_WARN_IF(NS_FAILED(mozilla::dom::cache::
                               LockedDirectoryPaddingGet(dir,
                                                         &paddingSize)))) {
        rv = LockedGetPaddingSizeFromDB(dir, aGroup, aOrigin, &paddingSize);
        if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
      }
    }

    aUsageInfo->AppendToFileUsage(paddingSize);

    nsCOMPtr<nsISimpleEnumerator> entries;
    rv = dir->GetDirectoryEntries(getter_AddRefs(entries));
    if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }

    bool hasMore;
    while (NS_SUCCEEDED(rv = entries->HasMoreElements(&hasMore)) && hasMore &&
           !aCanceled) {
      nsCOMPtr<nsISupports> entry;
      rv = entries->GetNext(getter_AddRefs(entry));
      if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }

      nsCOMPtr<nsIFile> file = do_QueryInterface(entry);

      nsAutoString leafName;
      rv = file->GetLeafName(leafName);
      if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }

      bool isDir;
      rv = file->IsDirectory(&isDir);
      if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }

      if (isDir) {
        if (leafName.EqualsLiteral("morgue")) {
          rv = GetBodyUsage(file, aCanceled, aUsageInfo);
          if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
        } else {
          NS_WARNING("Unknown Cache directory found!");
        }

        continue;
      }

      // Ignore transient sqlite files and marker files
      if (leafName.EqualsLiteral("caches.sqlite-journal") ||
          leafName.EqualsLiteral("caches.sqlite-shm") ||
          leafName.Find(NS_LITERAL_CSTRING("caches.sqlite-mj"), false, 0, 0) == 0 ||
          leafName.EqualsLiteral("context_open.marker")) {
        continue;
      }

      if (leafName.EqualsLiteral("caches.sqlite") ||
          leafName.EqualsLiteral("caches.sqlite-wal")) {
        int64_t fileSize;
        rv = file->GetFileSize(&fileSize);
        if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
        MOZ_DIAGNOSTIC_ASSERT(fileSize >= 0);

        aUsageInfo->AppendToDatabaseUsage(fileSize);
        continue;
      }

      // Ignore directory padding file
      if (leafName.EqualsLiteral(PADDING_FILE_NAME) ||
          leafName.EqualsLiteral(PADDING_TMP_FILE_NAME)) {
        continue;
      }

      NS_WARNING("Unknown Cache file found!");
    }

    return NS_OK;
  }

  virtual void
  OnOriginClearCompleted(PersistenceType aPersistenceType,
                         const nsACString& aOrigin) override
  {
    // Nothing to do here.
  }

  virtual void
  ReleaseIOThreadObjects() override
  {
    // Nothing to do here as the Context handles cleaning everything up
    // automatically.
  }

  virtual void
  AbortOperations(const nsACString& aOrigin) override
  {
    AssertIsOnBackgroundThread();

    Manager::Abort(aOrigin);
  }

  virtual void
  AbortOperationsForProcess(ContentParentId aContentParentId) override
  {
    // The Cache and Context can be shared by multiple client processes.  They
    // are not exclusively owned by a single process.
    //
    // As far as I can tell this is used by QuotaManager to abort operations
    // when a particular process goes away.  We definitely don't want this
    // since we are shared.  Also, the Cache actor code already properly
    // handles asynchronous actor destruction when the child process dies.
    //
    // Therefore, do nothing here.
  }

  virtual void
  StartIdleMaintenance() override
  { }

  virtual void
  StopIdleMaintenance() override
  { }

  virtual void
  ShutdownWorkThreads() override
  {
    AssertIsOnBackgroundThread();

    // spins the event loop and synchronously shuts down all Managers
    Manager::ShutdownAll();
  }

  nsresult
  UpgradeStorageFrom2_0To2_1(nsIFile* aDirectory) override
  {
    AssertIsOnIOThread();
    MOZ_DIAGNOSTIC_ASSERT(aDirectory);

    MutexAutoLock lock(mDirPaddingFileMutex);

    nsresult rv = mozilla::dom::cache::LockedDirectoryPaddingInit(aDirectory);
    if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }

    return rv;
  }

  // static
  template<typename Callable>
  nsresult
  MaybeUpdatePaddingFileInternal(nsIFile* aBaseDir,
                                 mozIStorageConnection* aConn,
                                 const int64_t aIncreaseSize,
                                 const int64_t aDecreaseSize,
                                 Callable aCommitHook)
  {
    MOZ_ASSERT(!NS_IsMainThread());
    MOZ_DIAGNOSTIC_ASSERT(aBaseDir);
    MOZ_DIAGNOSTIC_ASSERT(aConn);
    MOZ_DIAGNOSTIC_ASSERT(aIncreaseSize >= 0);
    MOZ_DIAGNOSTIC_ASSERT(aDecreaseSize >= 0);

    nsresult rv;

    // Temporary should be removed at the end of each action. If not, it means
    // the failure happened.
    bool temporaryPaddingFileExist =
      mozilla::dom::cache::DirectoryPaddingFileExists(aBaseDir,
                                                      DirPaddingFile::TMP_FILE);

    if (aIncreaseSize == aDecreaseSize && !temporaryPaddingFileExist) {
      // Early return here, since most cache actions won't modify padding size.
      rv = aCommitHook();
      Unused << NS_WARN_IF(NS_FAILED(rv));
      return rv;
    }

    {
      MutexAutoLock lock(mDirPaddingFileMutex);
      rv =
        mozilla::dom::cache::
        LockedUpdateDirectoryPaddingFile(aBaseDir, aConn, aIncreaseSize,
                                         aDecreaseSize,
                                         temporaryPaddingFileExist);
      if (NS_WARN_IF(NS_FAILED(rv))) {
        // Don't delete the temporary padding file here to force the next action
        // recalculate the padding size.
        return rv;
      }

      rv = aCommitHook();
      if (NS_WARN_IF(NS_FAILED(rv))) {
        // Don't delete the temporary padding file here to force the next action
        // recalculate the padding size.
        return rv;
      }

      rv = mozilla::dom::cache::LockedDirectoryPaddingFinalizeWrite(aBaseDir);
      if (NS_WARN_IF(NS_FAILED(rv))) {
        // Force restore file next time.
        Unused << mozilla::dom::cache::
                  LockedDirectoryPaddingDeleteFile(aBaseDir,
                                                   DirPaddingFile::FILE);

        // Ensure that we are able to force the padding file to be restored.
        MOZ_ASSERT(
          mozilla::dom::cache::
          DirectoryPaddingFileExists(aBaseDir, DirPaddingFile::TMP_FILE));

        // Since both the body file and header have been stored in the
        // file-system, just make the action be resolve and let the padding file
        // be restored in the next action.
        rv = NS_OK;
      }
    }

    return rv;
  }

  // static
  nsresult
  RestorePaddingFileInternal(nsIFile* aBaseDir, mozIStorageConnection* aConn)
  {
    MOZ_ASSERT(!NS_IsMainThread());
    MOZ_DIAGNOSTIC_ASSERT(aBaseDir);
    MOZ_DIAGNOSTIC_ASSERT(aConn);

    int64_t dummyPaddingSize;

    MutexAutoLock lock(mDirPaddingFileMutex);

    nsresult rv =
      mozilla::dom::cache::
      LockedDirectoryPaddingRestore(aBaseDir, aConn, /* aMustRestore */ true,
                                    &dummyPaddingSize);
    Unused << NS_WARN_IF(NS_FAILED(rv));

    return rv;
  }

  // static
  nsresult
  WipePaddingFileInternal(const QuotaInfo& aQuotaInfo, nsIFile* aBaseDir)
  {
    MOZ_ASSERT(!NS_IsMainThread());
    MOZ_DIAGNOSTIC_ASSERT(aBaseDir);

    MutexAutoLock lock(mDirPaddingFileMutex);

    MOZ_ASSERT(mozilla::dom::cache::
               DirectoryPaddingFileExists(aBaseDir, DirPaddingFile::FILE));

    int64_t paddingSize = 0;
    bool temporaryPaddingFileExist =
      mozilla::dom::cache::
      DirectoryPaddingFileExists(aBaseDir, DirPaddingFile::TMP_FILE);

    if (temporaryPaddingFileExist ||
        NS_WARN_IF(NS_FAILED(
          mozilla::dom::cache::
          LockedDirectoryPaddingGet(aBaseDir, &paddingSize)))) {
      // XXXtt: Maybe have a method in the QuotaManager to clean the usage under
      // the quota client and the origin.
      // There is nothing we can do to recover the file.
      NS_WARNING("Cannnot read padding size from file!");
      paddingSize = 0;
    }

    if (paddingSize > 0) {
      mozilla::dom::cache::DecreaseUsageForQuotaInfo(aQuotaInfo, paddingSize);
    }

    nsresult rv =
      mozilla::dom::cache::
      LockedDirectoryPaddingDeleteFile(aBaseDir, DirPaddingFile::FILE);
    if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }

    // Remove temporary file if we have one.
    rv = mozilla::dom::cache::
         LockedDirectoryPaddingDeleteFile(aBaseDir, DirPaddingFile::TMP_FILE);
    if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }

    rv = mozilla::dom::cache::LockedDirectoryPaddingInit(aBaseDir);
    Unused << NS_WARN_IF(NS_FAILED(rv));

    return rv;
  }

private:
  ~CacheQuotaClient()
  {
    AssertIsOnBackgroundThread();
    MOZ_DIAGNOSTIC_ASSERT(sInstance == this);

    sInstance = nullptr;
  }

  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(CacheQuotaClient, override)

  // Mutex lock to protect directroy padding files. It should only be acquired
  // in DOM Cache IO threads and Quota IO thread.
  mozilla::Mutex mDirPaddingFileMutex;
};

// static
CacheQuotaClient* CacheQuotaClient::sInstance = nullptr;

} // namespace

namespace mozilla {
namespace dom {
namespace cache {

// static
already_AddRefed<quota::Client> CreateQuotaClient()
{
  AssertIsOnBackgroundThread();

  RefPtr<CacheQuotaClient> ref = new CacheQuotaClient();
  return ref.forget();
}

// static
template<typename Callable>
nsresult
MaybeUpdatePaddingFile(nsIFile* aBaseDir,
                       mozIStorageConnection* aConn,
                       const int64_t aIncreaseSize,
                       const int64_t aDecreaseSize,
                       Callable aCommitHook)
{
  MOZ_ASSERT(!NS_IsMainThread());
  MOZ_DIAGNOSTIC_ASSERT(aBaseDir);
  MOZ_DIAGNOSTIC_ASSERT(aConn);
  MOZ_DIAGNOSTIC_ASSERT(aIncreaseSize >= 0);
  MOZ_DIAGNOSTIC_ASSERT(aDecreaseSize >= 0);

  RefPtr<CacheQuotaClient> cacheQuotaClient = CacheQuotaClient::Get();
  MOZ_DIAGNOSTIC_ASSERT(cacheQuotaClient);

  nsresult rv =
    cacheQuotaClient->MaybeUpdatePaddingFileInternal(aBaseDir, aConn,
                                                     aIncreaseSize,
                                                     aDecreaseSize,
                                                     aCommitHook);
  Unused << NS_WARN_IF(NS_FAILED(rv));

  return rv;
}

// static
nsresult
RestorePaddingFile(nsIFile* aBaseDir, mozIStorageConnection* aConn)
{
  MOZ_ASSERT(!NS_IsMainThread());
  MOZ_DIAGNOSTIC_ASSERT(aBaseDir);
  MOZ_DIAGNOSTIC_ASSERT(aConn);

  RefPtr<CacheQuotaClient> cacheQuotaClient = CacheQuotaClient::Get();
  MOZ_DIAGNOSTIC_ASSERT(cacheQuotaClient);

  nsresult rv =
    cacheQuotaClient->RestorePaddingFileInternal(aBaseDir, aConn);
  Unused << NS_WARN_IF(NS_FAILED(rv));

  return rv;
}

// static
nsresult
WipePaddingFile(const QuotaInfo& aQuotaInfo, nsIFile* aBaseDir)
{
  MOZ_ASSERT(!NS_IsMainThread());
  MOZ_DIAGNOSTIC_ASSERT(aBaseDir);

  RefPtr<CacheQuotaClient> cacheQuotaClient = CacheQuotaClient::Get();
  MOZ_DIAGNOSTIC_ASSERT(cacheQuotaClient);

  nsresult rv =
    cacheQuotaClient->WipePaddingFileInternal(aQuotaInfo, aBaseDir);
  Unused << NS_WARN_IF(NS_FAILED(rv));

  return rv;
}
} // namespace cache
} // namespace dom
} // namespace mozilla