The Tor Browser: storage/src/mozStorageService.cpp@b8a032363ba2 (annotated)

storage/src/mozStorageService.cpp@b8a032363ba2 (annotated)

storage/src/mozStorageService.cpp

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
  * vim: sw=2 ts=2 et lcs=trail\:.,tab\:>~ :
  * 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/Attributes.h"
 #include "mozilla/DebugOnly.h"
 #include "mozStorageService.h"
 #include "mozStorageConnection.h"
 #include "prinit.h"
 #include "nsAutoPtr.h"
 #include "nsCollationCID.h"
 #include "nsEmbedCID.h"
 #include "nsThreadUtils.h"
 #include "mozStoragePrivateHelpers.h"
 #include "nsILocale.h"
 #include "nsILocaleService.h"
 #include "nsIXPConnect.h"
 #include "nsIObserverService.h"
 #include "nsIPropertyBag2.h"
 #include "mozilla/Services.h"
 #include "mozilla/Preferences.h"
 #include "mozilla/LateWriteChecks.h"
 #include "mozIStorageCompletionCallback.h"
 #include "mozIStoragePendingStatement.h"
 #include "sqlite3.h"
 #ifdef SQLITE_OS_WIN
 // "windows.h" was included and it can #define lots of things we care about...
 #undef CompareString
 #endif
 #include "nsIPromptService.h"
 #ifdef MOZ_STORAGE_MEMORY
 #  include "mozmemory.h"
 #  ifdef MOZ_DMD
 #    include "DMD.h"
 #  endif
 #endif
 ////////////////////////////////////////////////////////////////////////////////
 //// Defines
 #define PREF_TS_SYNCHRONOUS "toolkit.storage.synchronous"
 #define PREF_TS_SYNCHRONOUS_DEFAULT 1
 #define PREF_TS_PAGESIZE "toolkit.storage.pageSize"
 // This value must be kept in sync with the value of SQLITE_DEFAULT_PAGE_SIZE in
 // db/sqlite3/src/Makefile.in.
 #define PREF_TS_PAGESIZE_DEFAULT 32768
 namespace mozilla {
 namespace storage {
 ////////////////////////////////////////////////////////////////////////////////
 //// Memory Reporting
 #ifdef MOZ_DMD
 static mozilla::Atomic<size_t> gSqliteMemoryUsed;
 #endif
 static int64_t
 StorageSQLiteDistinguishedAmount()
 {
   return ::sqlite3_memory_used();
 }
 /**
  * Passes a single SQLite memory statistic to a memory reporter callback.
  *
  * @param aHandleReport
  *        The callback.
  * @param aData
  *        The data for the callback.
  * @param aConn
  *        The SQLite connection.
  * @param aPathHead
  *        Head of the path for the memory report.
  * @param aKind
  *        The memory report statistic kind, one of "stmt", "cache" or
  *        "schema".
  * @param aDesc
  *        The memory report description.
  * @param aOption
  *        The SQLite constant for getting the measurement.
  * @param aTotal
  *        The accumulator for the measurement.
  */
 nsresult
 ReportConn(nsIHandleReportCallback *aHandleReport,
            nsISupports *aData,
            Connection *aConn,
            const nsACString &aPathHead,
            const nsACString &aKind,
            const nsACString &aDesc,
            int32_t aOption,
            size_t *aTotal)
 {
   nsCString path(aPathHead);
   path.Append(aKind);
   path.AppendLiteral("-used");
   int32_t val = aConn->getSqliteRuntimeStatus(aOption);
   nsresult rv = aHandleReport->Callback(EmptyCString(), path,
                                         nsIMemoryReporter::KIND_HEAP,
                                         nsIMemoryReporter::UNITS_BYTES,
                                         int64_t(val), aDesc, aData);
   NS_ENSURE_SUCCESS(rv, rv);
   *aTotal += val;
   return NS_OK;
 }
 // Warning: To get a Connection's measurements requires holding its lock.
 // There may be a delay getting the lock if another thread is accessing the
 // Connection.  This isn't very nice if CollectReports is called from the main
 // thread!  But at the time of writing this function is only called when
 // about:memory is loaded (not, for example, when telemetry pings occur) and
 // any delays in that case aren't so bad.
 NS_IMETHODIMP
 Service::CollectReports(nsIHandleReportCallback *aHandleReport,
                         nsISupports *aData)
 {
   nsresult rv;
   size_t totalConnSize = 0;
   {
     nsTArray<nsRefPtr<Connection> > connections;
     getConnections(connections);
     for (uint32_t i = 0; i < connections.Length(); i++) {
       nsRefPtr<Connection> &conn = connections[i];
       // Someone may have closed the Connection, in which case we skip it.
       bool isReady;
       (void)conn->GetConnectionReady(&isReady);
       if (!isReady) {
           continue;
       }
       nsCString pathHead("explicit/storage/sqlite/");
       pathHead.Append(conn->getFilename());
       pathHead.AppendLiteral("/");
       SQLiteMutexAutoLock lockedScope(conn->sharedDBMutex);
       NS_NAMED_LITERAL_CSTRING(stmtDesc,
         "Memory (approximate) used by all prepared statements used by "
         "connections to this database.");
       rv = ReportConn(aHandleReport, aData, conn, pathHead,
                       NS_LITERAL_CSTRING("stmt"), stmtDesc,
                       SQLITE_DBSTATUS_STMT_USED, &totalConnSize);
       NS_ENSURE_SUCCESS(rv, rv);
       NS_NAMED_LITERAL_CSTRING(cacheDesc,
         "Memory (approximate) used by all pager caches used by connections "
         "to this database.");
       rv = ReportConn(aHandleReport, aData, conn, pathHead,
                       NS_LITERAL_CSTRING("cache"), cacheDesc,
                       SQLITE_DBSTATUS_CACHE_USED, &totalConnSize);
       NS_ENSURE_SUCCESS(rv, rv);
       NS_NAMED_LITERAL_CSTRING(schemaDesc,
         "Memory (approximate) used to store the schema for all databases "
         "associated with connections to this database.");
       rv = ReportConn(aHandleReport, aData, conn, pathHead,
                       NS_LITERAL_CSTRING("schema"), schemaDesc,
                       SQLITE_DBSTATUS_SCHEMA_USED, &totalConnSize);
       NS_ENSURE_SUCCESS(rv, rv);
     }
 #ifdef MOZ_DMD
     if (::sqlite3_memory_used() != int64_t(gSqliteMemoryUsed)) {
       NS_WARNING("memory consumption reported by SQLite doesn't match "
                  "our measurements");
     }
 #endif
   }
   int64_t other = ::sqlite3_memory_used() - totalConnSize;
   rv = aHandleReport->Callback(
           EmptyCString(),
           NS_LITERAL_CSTRING("explicit/storage/sqlite/other"),
           KIND_HEAP, UNITS_BYTES, other,
           NS_LITERAL_CSTRING("All unclassified sqlite memory."),
           aData);
   NS_ENSURE_SUCCESS(rv, rv);
   return NS_OK;
 }
 ////////////////////////////////////////////////////////////////////////////////
 //// Service
 NS_IMPL_ISUPPORTS(
   Service,
   mozIStorageService,
   nsIObserver,
   nsIMemoryReporter
 )
 Service *Service::gService = nullptr;
 Service *
 Service::getSingleton()
 {
   if (gService) {
     NS_ADDREF(gService);
     return gService;
   }
   // Ensure that we are using the same version of SQLite that we compiled with
   // or newer.  Our configure check ensures we are using a new enough version
   // at compile time.
   if (SQLITE_VERSION_NUMBER > ::sqlite3_libversion_number()) {
     nsCOMPtr<nsIPromptService> ps(do_GetService(NS_PROMPTSERVICE_CONTRACTID));
     if (ps) {
       nsAutoString title, message;
       title.AppendLiteral("SQLite Version Error");
       message.AppendLiteral("The application has been updated, but your version "
                           "of SQLite is too old and the application cannot "
                           "run.");
       (void)ps->Alert(nullptr, title.get(), message.get());
     }
     ::PR_Abort();
   }
   // The first reference to the storage service must be obtained on the
   // main thread.
   NS_ENSURE_TRUE(NS_IsMainThread(), nullptr);
   gService = new Service();
   if (gService) {
     NS_ADDREF(gService);
     if (NS_FAILED(gService->initialize()))
       NS_RELEASE(gService);
   }
   return gService;
 }
 nsIXPConnect *Service::sXPConnect = nullptr;
 // static
 already_AddRefed<nsIXPConnect>
 Service::getXPConnect()
 {
   NS_PRECONDITION(NS_IsMainThread(),
                   "Must only get XPConnect on the main thread!");
   NS_PRECONDITION(gService,
                   "Can not get XPConnect without an instance of our service!");
   // If we've been shutdown, sXPConnect will be null.  To prevent leaks, we do
   // not cache the service after this point.
   nsCOMPtr<nsIXPConnect> xpc(sXPConnect);
   if (!xpc)
     xpc = do_GetService(nsIXPConnect::GetCID());
   NS_ASSERTION(xpc, "Could not get XPConnect!");
   return xpc.forget();
 }
 int32_t Service::sSynchronousPref;
 // static
 int32_t
 Service::getSynchronousPref()
 {
   return sSynchronousPref;
 }
 int32_t Service::sDefaultPageSize = PREF_TS_PAGESIZE_DEFAULT;
 Service::Service()
 : mMutex("Service::mMutex")
 , mSqliteVFS(nullptr)
 , mRegistrationMutex("Service::mRegistrationMutex")
 , mConnections()
 {
 }
 Service::~Service()
 {
   mozilla::UnregisterWeakMemoryReporter(this);
   mozilla::UnregisterStorageSQLiteDistinguishedAmount();
   int rc = sqlite3_vfs_unregister(mSqliteVFS);
   if (rc != SQLITE_OK)
     NS_WARNING("Failed to unregister sqlite vfs wrapper.");
   // Shutdown the sqlite3 API.  Warn if shutdown did not turn out okay, but
   // there is nothing actionable we can do in that case.
   rc = ::sqlite3_shutdown();
   if (rc != SQLITE_OK)
     NS_WARNING("sqlite3 did not shutdown cleanly.");
   DebugOnly<bool> shutdownObserved = !sXPConnect;
   NS_ASSERTION(shutdownObserved, "Shutdown was not observed!");
   gService = nullptr;
   delete mSqliteVFS;
   mSqliteVFS = nullptr;
 }
 void
 Service::registerConnection(Connection *aConnection)
 {
   mRegistrationMutex.AssertNotCurrentThreadOwns();
   MutexAutoLock mutex(mRegistrationMutex);
   (void)mConnections.AppendElement(aConnection);
 }
 void
 Service::unregisterConnection(Connection *aConnection)
 {
   // If this is the last Connection it might be the only thing keeping Service
   // alive.  So ensure that Service is destroyed only after the Connection is
   // cleanly unregistered and destroyed.
   nsRefPtr<Service> kungFuDeathGrip(this);
   {
     mRegistrationMutex.AssertNotCurrentThreadOwns();
     MutexAutoLock mutex(mRegistrationMutex);
     DebugOnly<bool> removed = mConnections.RemoveElement(aConnection);
     // Assert if we try to unregister a non-existent connection.
     MOZ_ASSERT(removed);
   }
 }
 void
 Service::getConnections(/* inout */ nsTArray<nsRefPtr<Connection> >& aConnections)
 {
   mRegistrationMutex.AssertNotCurrentThreadOwns();
   MutexAutoLock mutex(mRegistrationMutex);
   aConnections.Clear();
   aConnections.AppendElements(mConnections);
 }
 void
 Service::minimizeMemory()
 {
   nsTArray<nsRefPtr<Connection> > connections;
   getConnections(connections);
   for (uint32_t i = 0; i < connections.Length(); i++) {
     nsRefPtr<Connection> conn = connections[i];
     if (conn->connectionReady()) {
       NS_NAMED_LITERAL_CSTRING(shrinkPragma, "PRAGMA shrink_memory");
       nsCOMPtr<mozIStorageConnection> syncConn = do_QueryInterface(
         NS_ISUPPORTS_CAST(mozIStorageAsyncConnection*, conn));
       DebugOnly<nsresult> rv;
       if (!syncConn) {
         nsCOMPtr<mozIStoragePendingStatement> ps;
         rv = connections[i]->ExecuteSimpleSQLAsync(shrinkPragma, nullptr,
           getter_AddRefs(ps));
       } else {
         rv = connections[i]->ExecuteSimpleSQL(shrinkPragma);
       }
       MOZ_ASSERT(NS_SUCCEEDED(rv),
         "Should have been able to purge sqlite caches");
     }
   }
 }
 void
 Service::shutdown()
 {
   NS_IF_RELEASE(sXPConnect);
 }
 sqlite3_vfs *ConstructTelemetryVFS();
 #ifdef MOZ_STORAGE_MEMORY
 namespace {
 // By default, SQLite tracks the size of all its heap blocks by adding an extra
 // 8 bytes at the start of the block to hold the size.  Unfortunately, this
 // causes a lot of 2^N-sized allocations to be rounded up by jemalloc
 // allocator, wasting memory.  For example, a request for 1024 bytes has 8
 // bytes added, becoming a request for 1032 bytes, and jemalloc rounds this up
 // to 2048 bytes, wasting 1012 bytes.  (See bug 676189 for more details.)
 //
 // So we register jemalloc as the malloc implementation, which avoids this
 // 8-byte overhead, and thus a lot of waste.  This requires us to provide a
 // function, sqliteMemRoundup(), which computes the actual size that will be
 // allocated for a given request.  SQLite uses this function before all
 // allocations, and may be able to use any excess bytes caused by the rounding.
 //
 // Note: the wrappers for moz_malloc, moz_realloc and moz_malloc_usable_size
 // are necessary because the sqlite_mem_methods type signatures differ slightly
 // from the standard ones -- they use int instead of size_t.  But we don't need
 // a wrapper for moz_free.
 #ifdef MOZ_DMD
 // sqlite does its own memory accounting, and we use its numbers in our memory
 // reporters.  But we don't want sqlite's heap blocks to show up in DMD's
 // output as unreported, so we mark them as reported when they're allocated and
 // mark them as unreported when they are freed.
 //
 // In other words, we are marking all sqlite heap blocks as reported even
 // though we're not reporting them ourselves.  Instead we're trusting that
 // sqlite is fully and correctly accounting for all of its heap blocks via its
 // own memory accounting.  Well, we don't have to trust it entirely, because
 // it's easy to keep track (while doing this DMD-specific marking) of exactly
 // how much memory SQLite is using.  And we can compare that against what
 // SQLite reports it is using.
 MOZ_DEFINE_MALLOC_SIZE_OF_ON_ALLOC(SqliteMallocSizeOfOnAlloc)
 MOZ_DEFINE_MALLOC_SIZE_OF_ON_FREE(SqliteMallocSizeOfOnFree)
 #endif
 static void *sqliteMemMalloc(int n)
 {
   void* p = ::moz_malloc(n);
 #ifdef MOZ_DMD
   gSqliteMemoryUsed += SqliteMallocSizeOfOnAlloc(p);
 #endif
   return p;
 }
 static void sqliteMemFree(void *p)
 {
 #ifdef MOZ_DMD
   gSqliteMemoryUsed -= SqliteMallocSizeOfOnFree(p);
 #endif
   ::moz_free(p);
 }
 static void *sqliteMemRealloc(void *p, int n)
 {
 #ifdef MOZ_DMD
   gSqliteMemoryUsed -= SqliteMallocSizeOfOnFree(p);
   void *pnew = ::moz_realloc(p, n);
   if (pnew) {
     gSqliteMemoryUsed += SqliteMallocSizeOfOnAlloc(pnew);
   } else {
     // realloc failed;  undo the SqliteMallocSizeOfOnFree from above
     gSqliteMemoryUsed += SqliteMallocSizeOfOnAlloc(p);
   }
   return pnew;
 #else
   return ::moz_realloc(p, n);
 #endif
 }
 static int sqliteMemSize(void *p)
 {
   return ::moz_malloc_usable_size(p);
 }
 static int sqliteMemRoundup(int n)
 {
   n = malloc_good_size(n);
   // jemalloc can return blocks of size 2 and 4, but SQLite requires that all
   // allocations be 8-aligned.  So we round up sub-8 requests to 8.  This
   // wastes a small amount of memory but is obviously safe.
   return n <= 8 ? 8 : n;
 }
 static int sqliteMemInit(void *p)
 {
   return 0;
 }
 static void sqliteMemShutdown(void *p)
 {
 }
 const sqlite3_mem_methods memMethods = {
   &sqliteMemMalloc,
   &sqliteMemFree,
   &sqliteMemRealloc,
   &sqliteMemSize,
   &sqliteMemRoundup,
   &sqliteMemInit,
   &sqliteMemShutdown,
   nullptr
 };
 } // anonymous namespace
 #endif  // MOZ_STORAGE_MEMORY
 static const char* sObserverTopics[] = {
   "memory-pressure",
   "xpcom-shutdown",
   "xpcom-shutdown-threads"
 };
 nsresult
 Service::initialize()
 {
   MOZ_ASSERT(NS_IsMainThread(), "Must be initialized on the main thread");
   int rc;
 #ifdef MOZ_STORAGE_MEMORY
   rc = ::sqlite3_config(SQLITE_CONFIG_MALLOC, &memMethods);
   if (rc != SQLITE_OK)
     return convertResultCode(rc);
 #endif
   // Explicitly initialize sqlite3.  Although this is implicitly called by
   // various sqlite3 functions (and the sqlite3_open calls in our case),
   // the documentation suggests calling this directly.  So we do.
   rc = ::sqlite3_initialize();
   if (rc != SQLITE_OK)
     return convertResultCode(rc);
   mSqliteVFS = ConstructTelemetryVFS();
   if (mSqliteVFS) {
     rc = sqlite3_vfs_register(mSqliteVFS, 1);
     if (rc != SQLITE_OK)
       return convertResultCode(rc);
   } else {
     NS_WARNING("Failed to register telemetry VFS");
   }
   // Register for xpcom-shutdown so we can cleanup after ourselves.  The
   // observer service can only be used on the main thread.
   nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
   NS_ENSURE_TRUE(os, NS_ERROR_FAILURE);
   for (size_t i = 0; i < ArrayLength(sObserverTopics); ++i) {
     nsresult rv = os->AddObserver(this, sObserverTopics[i], false);
     if (NS_WARN_IF(NS_FAILED(rv))) {
       return rv;
     }
   }
   // We cache XPConnect for our language helpers.  XPConnect can only be
   // used on the main thread.
   (void)CallGetService(nsIXPConnect::GetCID(), &sXPConnect);
   // We need to obtain the toolkit.storage.synchronous preferences on the main
   // thread because the preference service can only be accessed there.  This
   // is cached in the service for all future Open[Unshared]Database calls.
   sSynchronousPref =
     Preferences::GetInt(PREF_TS_SYNCHRONOUS, PREF_TS_SYNCHRONOUS_DEFAULT);
   // We need to obtain the toolkit.storage.pageSize preferences on the main
   // thread because the preference service can only be accessed there.  This
   // is cached in the service for all future Open[Unshared]Database calls.
   sDefaultPageSize =
       Preferences::GetInt(PREF_TS_PAGESIZE, PREF_TS_PAGESIZE_DEFAULT);
   mozilla::RegisterWeakMemoryReporter(this);
   mozilla::RegisterStorageSQLiteDistinguishedAmount(StorageSQLiteDistinguishedAmount);
   return NS_OK;
 }
 int
 Service::localeCompareStrings(const nsAString &aStr1,
                               const nsAString &aStr2,
                               int32_t aComparisonStrength)
 {
   // The implementation of nsICollation.CompareString() is platform-dependent.
   // On Linux it's not thread-safe.  It may not be on Windows and OS X either,
   // but it's more difficult to tell.  We therefore synchronize this method.
   MutexAutoLock mutex(mMutex);
   nsICollation *coll = getLocaleCollation();
   if (!coll) {
     NS_ERROR("Storage service has no collation");
     return 0;
   }
   int32_t res;
   nsresult rv = coll->CompareString(aComparisonStrength, aStr1, aStr2, &res);
   if (NS_FAILED(rv)) {
     NS_ERROR("Collation compare string failed");
     return 0;
   }
   return res;
 }
 nsICollation *
 Service::getLocaleCollation()
 {
   mMutex.AssertCurrentThreadOwns();
   if (mLocaleCollation)
     return mLocaleCollation;
   nsCOMPtr<nsILocaleService> svc(do_GetService(NS_LOCALESERVICE_CONTRACTID));
   if (!svc) {
     NS_WARNING("Could not get locale service");
     return nullptr;
   }
   nsCOMPtr<nsILocale> appLocale;
   nsresult rv = svc->GetApplicationLocale(getter_AddRefs(appLocale));
   if (NS_FAILED(rv)) {
     NS_WARNING("Could not get application locale");
     return nullptr;
   }
   nsCOMPtr<nsICollationFactory> collFact =
     do_CreateInstance(NS_COLLATIONFACTORY_CONTRACTID);
   if (!collFact) {
     NS_WARNING("Could not create collation factory");
     return nullptr;
   }
   rv = collFact->CreateCollation(appLocale, getter_AddRefs(mLocaleCollation));
   if (NS_FAILED(rv)) {
     NS_WARNING("Could not create collation");
     return nullptr;
   }
   return mLocaleCollation;
 }
 ////////////////////////////////////////////////////////////////////////////////
 //// mozIStorageService
 NS_IMETHODIMP
 Service::OpenSpecialDatabase(const char *aStorageKey,
                              mozIStorageConnection **_connection)
 {
   nsresult rv;
   nsCOMPtr<nsIFile> storageFile;
   if (::strcmp(aStorageKey, "memory") == 0) {
     // just fall through with nullptr storageFile, this will cause the storage
     // connection to use a memory DB.
   }
   else {
     return NS_ERROR_INVALID_ARG;
   }
   nsRefPtr<Connection> msc = new Connection(this, SQLITE_OPEN_READWRITE, false);
   rv = storageFile ? msc->initialize(storageFile) : msc->initialize();
   NS_ENSURE_SUCCESS(rv, rv);
   msc.forget(_connection);
   return NS_OK;
 }
 namespace {
 class AsyncInitDatabase MOZ_FINAL : public nsRunnable
 {
 public:
   AsyncInitDatabase(Connection* aConnection,
                     nsIFile* aStorageFile,
                     int32_t aGrowthIncrement,
                     mozIStorageCompletionCallback* aCallback)
     : mConnection(aConnection)
     , mStorageFile(aStorageFile)
     , mGrowthIncrement(aGrowthIncrement)
     , mCallback(aCallback)
   {
     MOZ_ASSERT(NS_IsMainThread());
   }
   NS_IMETHOD Run()
   {
     MOZ_ASSERT(!NS_IsMainThread());
     nsresult rv = mStorageFile ? mConnection->initialize(mStorageFile)
                                : mConnection->initialize();
     if (NS_FAILED(rv)) {
       return DispatchResult(rv, nullptr);
     }
     if (mGrowthIncrement >= 0) {
       // Ignore errors. In the future, we might wish to log them.
       (void)mConnection->SetGrowthIncrement(mGrowthIncrement, EmptyCString());
     }
     return DispatchResult(NS_OK, NS_ISUPPORTS_CAST(mozIStorageAsyncConnection*,
                           mConnection));
   }
 private:
   nsresult DispatchResult(nsresult aStatus, nsISupports* aValue) {
     nsRefPtr<CallbackComplete> event =
       new CallbackComplete(aStatus,
                            aValue,
                            mCallback.forget());
     return NS_DispatchToMainThread(event);
   }
   ~AsyncInitDatabase()
   {
     nsCOMPtr<nsIThread> thread;
     DebugOnly<nsresult> rv = NS_GetMainThread(getter_AddRefs(thread));
     MOZ_ASSERT(NS_SUCCEEDED(rv));
     (void)NS_ProxyRelease(thread, mStorageFile);
     // Handle ambiguous nsISupports inheritance.
     Connection *rawConnection = nullptr;
     mConnection.swap(rawConnection);
     (void)NS_ProxyRelease(thread, NS_ISUPPORTS_CAST(mozIStorageConnection *,
                                                     rawConnection));
     // Generally, the callback will be released by CallbackComplete.
     // However, if for some reason Run() is not executed, we still
     // need to ensure that it is released here.
     mozIStorageCompletionCallback *rawCallback = nullptr;
     mCallback.swap(rawCallback);
     (void)NS_ProxyRelease(thread, rawCallback);
   }
   nsRefPtr<Connection> mConnection;
   nsCOMPtr<nsIFile> mStorageFile;
   int32_t mGrowthIncrement;
   nsRefPtr<mozIStorageCompletionCallback> mCallback;
 };
 } // anonymous namespace
 NS_IMETHODIMP
 Service::OpenAsyncDatabase(nsIVariant *aDatabaseStore,
                            nsIPropertyBag2 *aOptions,
                            mozIStorageCompletionCallback *aCallback)
 {
   if (!NS_IsMainThread()) {
     return NS_ERROR_NOT_SAME_THREAD;
   }
   NS_ENSURE_ARG(aDatabaseStore);
   NS_ENSURE_ARG(aCallback);
   nsCOMPtr<nsIFile> storageFile;
   int flags = SQLITE_OPEN_READWRITE;
   nsCOMPtr<nsISupports> dbStore;
   nsresult rv = aDatabaseStore->GetAsISupports(getter_AddRefs(dbStore));
   if (NS_SUCCEEDED(rv)) {
     // Generally, aDatabaseStore holds the database nsIFile.
     storageFile = do_QueryInterface(dbStore, &rv);
     if (NS_FAILED(rv)) {
       return NS_ERROR_INVALID_ARG;
     }
     rv = storageFile->Clone(getter_AddRefs(storageFile));
     MOZ_ASSERT(NS_SUCCEEDED(rv));
     // Ensure that SQLITE_OPEN_CREATE is passed in for compatibility reasons.
     flags |= SQLITE_OPEN_CREATE;
     // Extract and apply the shared-cache option.
     bool shared = false;
     if (aOptions) {
       rv = aOptions->GetPropertyAsBool(NS_LITERAL_STRING("shared"), &shared);
       if (NS_FAILED(rv) && rv != NS_ERROR_NOT_AVAILABLE) {
         return NS_ERROR_INVALID_ARG;
       }
     }
     flags |= shared ? SQLITE_OPEN_SHAREDCACHE : SQLITE_OPEN_PRIVATECACHE;
   } else {
     // Sometimes, however, it's a special database name.
     nsAutoCString keyString;
     rv = aDatabaseStore->GetAsACString(keyString);
     if (NS_FAILED(rv) || !keyString.EqualsLiteral("memory")) {
       return NS_ERROR_INVALID_ARG;
     }
     // Just fall through with nullptr storageFile, this will cause the storage
     // connection to use a memory DB.
   }
   int32_t growthIncrement = -1;
   if (aOptions && storageFile) {
     rv = aOptions->GetPropertyAsInt32(NS_LITERAL_STRING("growthIncrement"),
                                       &growthIncrement);
     if (NS_FAILED(rv) && rv != NS_ERROR_NOT_AVAILABLE) {
       return NS_ERROR_INVALID_ARG;
     }
   }
   // Create connection on this thread, but initialize it on its helper thread.
   nsRefPtr<Connection> msc = new Connection(this, flags, true);
   nsCOMPtr<nsIEventTarget> target = msc->getAsyncExecutionTarget();
   MOZ_ASSERT(target, "Cannot initialize a connection that has been closed already");
   nsRefPtr<AsyncInitDatabase> asyncInit =
     new AsyncInitDatabase(msc,
                           storageFile,
                           growthIncrement,
                           aCallback);
   return target->Dispatch(asyncInit, nsIEventTarget::DISPATCH_NORMAL);
 }
 NS_IMETHODIMP
 Service::OpenDatabase(nsIFile *aDatabaseFile,
                       mozIStorageConnection **_connection)
 {
   NS_ENSURE_ARG(aDatabaseFile);
   // Always ensure that SQLITE_OPEN_CREATE is passed in for compatibility
   // reasons.
   int flags = SQLITE_OPEN_READWRITE | SQLITE_OPEN_SHAREDCACHE |
               SQLITE_OPEN_CREATE;
   nsRefPtr<Connection> msc = new Connection(this, flags, false);
   nsresult rv = msc->initialize(aDatabaseFile);
   NS_ENSURE_SUCCESS(rv, rv);
   msc.forget(_connection);
   return NS_OK;
 }
 NS_IMETHODIMP
 Service::OpenUnsharedDatabase(nsIFile *aDatabaseFile,
                               mozIStorageConnection **_connection)
 {
   NS_ENSURE_ARG(aDatabaseFile);
   // Always ensure that SQLITE_OPEN_CREATE is passed in for compatibility
   // reasons.
   int flags = SQLITE_OPEN_READWRITE | SQLITE_OPEN_PRIVATECACHE |
               SQLITE_OPEN_CREATE;
   nsRefPtr<Connection> msc = new Connection(this, flags, false);
   nsresult rv = msc->initialize(aDatabaseFile);
   NS_ENSURE_SUCCESS(rv, rv);
   msc.forget(_connection);
   return NS_OK;
 }
 NS_IMETHODIMP
 Service::OpenDatabaseWithFileURL(nsIFileURL *aFileURL,
                                  mozIStorageConnection **_connection)
 {
   NS_ENSURE_ARG(aFileURL);
   // Always ensure that SQLITE_OPEN_CREATE is passed in for compatibility
   // reasons.
   int flags = SQLITE_OPEN_READWRITE | SQLITE_OPEN_SHAREDCACHE |
               SQLITE_OPEN_CREATE | SQLITE_OPEN_URI;
   nsRefPtr<Connection> msc = new Connection(this, flags, false);
   nsresult rv = msc->initialize(aFileURL);
   NS_ENSURE_SUCCESS(rv, rv);
   msc.forget(_connection);
   return NS_OK;
 }
 NS_IMETHODIMP
 Service::BackupDatabaseFile(nsIFile *aDBFile,
                             const nsAString &aBackupFileName,
                             nsIFile *aBackupParentDirectory,
                             nsIFile **backup)
 {
   nsresult rv;
   nsCOMPtr<nsIFile> parentDir = aBackupParentDirectory;
   if (!parentDir) {
     // This argument is optional, and defaults to the same parent directory
     // as the current file.
     rv = aDBFile->GetParent(getter_AddRefs(parentDir));
     NS_ENSURE_SUCCESS(rv, rv);
   }
   nsCOMPtr<nsIFile> backupDB;
   rv = parentDir->Clone(getter_AddRefs(backupDB));
   NS_ENSURE_SUCCESS(rv, rv);
   rv = backupDB->Append(aBackupFileName);
   NS_ENSURE_SUCCESS(rv, rv);
   rv = backupDB->CreateUnique(nsIFile::NORMAL_FILE_TYPE, 0600);
   NS_ENSURE_SUCCESS(rv, rv);
   nsAutoString fileName;
   rv = backupDB->GetLeafName(fileName);
   NS_ENSURE_SUCCESS(rv, rv);
   rv = backupDB->Remove(false);
   NS_ENSURE_SUCCESS(rv, rv);
   backupDB.forget(backup);
   return aDBFile->CopyTo(parentDir, fileName);
 }
 ////////////////////////////////////////////////////////////////////////////////
 //// nsIObserver
 NS_IMETHODIMP
 Service::Observe(nsISupports *, const char *aTopic, const char16_t *)
 {
   if (strcmp(aTopic, "memory-pressure") == 0) {
     minimizeMemory();
   } else if (strcmp(aTopic, "xpcom-shutdown") == 0) {
     shutdown();
   } else if (strcmp(aTopic, "xpcom-shutdown-threads") == 0) {
     nsCOMPtr<nsIObserverService> os =
       mozilla::services::GetObserverService();
     for (size_t i = 0; i < ArrayLength(sObserverTopics); ++i) {
       (void)os->RemoveObserver(this, sObserverTopics[i]);
     }
     bool anyOpen = false;
     do {
       nsTArray<nsRefPtr<Connection> > connections;
       getConnections(connections);
       anyOpen = false;
       for (uint32_t i = 0; i < connections.Length(); i++) {
         nsRefPtr<Connection> &conn = connections[i];
         if (conn->isClosing()) {
           anyOpen = true;
           break;
         }
       }
       if (anyOpen) {
         nsCOMPtr<nsIThread> thread = do_GetCurrentThread();
         NS_ProcessNextEvent(thread);
       }
     } while (anyOpen);
     if (gShutdownChecks == SCM_CRASH) {
       nsTArray<nsRefPtr<Connection> > connections;
       getConnections(connections);
       for (uint32_t i = 0, n = connections.Length(); i < n; i++) {
         if (!connections[i]->isClosed()) {
           MOZ_CRASH();
         }
       }
     }
   }
   return NS_OK;
 }
 } // namespace storage
 } // namespace mozilla

The Tor Browser / annotate

storage/src/mozStorageService.cpp@b8a032363ba2 (annotated)

storage/src/mozStorageService.cpp