storage/mozStorageService.cpp

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
   2  * vim: sw=2 ts=2 et lcs=trail\:.,tab\:>~ :
   3  * This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "mozilla/Attributes.h"
   8 #include "mozilla/DebugOnly.h"
   9 #include "mozilla/SpinEventLoopUntil.h"
  10
  11 #include "mozStorageService.h"
  12 #include "mozStorageConnection.h"
  13 #include "nsComponentManagerUtils.h"
  14 #include "nsEmbedCID.h"
  15 #include "nsExceptionHandler.h"
  16 #include "nsThreadUtils.h"
  17 #include "mozStoragePrivateHelpers.h"
  18 #include "nsIObserverService.h"
  19 #include "nsIPropertyBag2.h"
  20 #include "mozilla/Services.h"
  21 #include "mozilla/LateWriteChecks.h"
  22 #include "mozIStorageCompletionCallback.h"
  23 #include "mozIStoragePendingStatement.h"
  24 #include "mozilla/StaticPrefs_storage.h"
  25 #include "mozilla/intl/Collator.h"
  26 #include "mozilla/intl/LocaleService.h"
  27
  28 #include "sqlite3.h"
  29 #include "mozilla/AutoSQLiteLifetime.h"
  30
  31 #ifdef XP_WIN
  32 // "windows.h" was included and it can #define lots of things we care about...
  33 #  undef CompareString
  34 #endif
  35
  36 using mozilla::intl::Collator;
  37
  38 namespace mozilla {
  39 namespace storage {
  40
  41 ////////////////////////////////////////////////////////////////////////////////
  42 //// Memory Reporting
  43
  44 #ifdef MOZ_DMD
  45 mozilla::Atomic<size_t> gSqliteMemoryUsed;
  46 #endif
  47
  48 static int64_t StorageSQLiteDistinguishedAmount() {
  49   return ::sqlite3_memory_used();
  50 }
  51
  52 /**
  53  * Passes a single SQLite memory statistic to a memory reporter callback.
  54  *
  55  * @param aHandleReport
  56  *        The callback.
  57  * @param aData
  58  *        The data for the callback.
  59  * @param aConn
  60  *        The SQLite connection.
  61  * @param aPathHead
  62  *        Head of the path for the memory report.
  63  * @param aKind
  64  *        The memory report statistic kind, one of "stmt", "cache" or
  65  *        "schema".
  66  * @param aDesc
  67  *        The memory report description.
  68  * @param aOption
  69  *        The SQLite constant for getting the measurement.
  70  * @param aTotal
  71  *        The accumulator for the measurement.
  72  */
  73 static void ReportConn(nsIHandleReportCallback* aHandleReport,
  74                        nsISupports* aData, Connection* aConn,
  75                        const nsACString& aPathHead, const nsACString& aKind,
  76                        const nsACString& aDesc, int32_t aOption,
  77                        size_t* aTotal) {
  78   nsCString path(aPathHead);
  79   path.Append(aKind);
  80   path.AppendLiteral("-used");
  81
  82   int32_t val = aConn->getSqliteRuntimeStatus(aOption);
  83   aHandleReport->Callback(""_ns, path, nsIMemoryReporter::KIND_HEAP,
  84                           nsIMemoryReporter::UNITS_BYTES, int64_t(val), aDesc,
  85                           aData);
  86   *aTotal += val;
  87 }
  88
  89 // Warning: To get a Connection's measurements requires holding its lock.
  90 // There may be a delay getting the lock if another thread is accessing the
  91 // Connection.  This isn't very nice if CollectReports is called from the main
  92 // thread!  But at the time of writing this function is only called when
  93 // about:memory is loaded (not, for example, when telemetry pings occur) and
  94 // any delays in that case aren't so bad.
  95 NS_IMETHODIMP
  96 Service::CollectReports(nsIHandleReportCallback* aHandleReport,
  97                         nsISupports* aData, bool aAnonymize) {
  98   size_t totalConnSize = 0;
  99   {
 100     nsTArray<RefPtr<Connection>> connections;
 101     getConnections(connections);
 102
 103     for (uint32_t i = 0; i < connections.Length(); i++) {
 104       RefPtr<Connection>& conn = connections[i];
 105
 106       // Someone may have closed the Connection, in which case we skip it.
 107       // Note that we have consumers of the synchronous API that are off the
 108       // main-thread, like the DOM Cache and IndexedDB, and as such we must be
 109       // sure that we have a connection.
 110       MutexAutoLock lockedAsyncScope(conn->sharedAsyncExecutionMutex);
 111       if (!conn->connectionReady()) {
 112         continue;
 113       }
 114
 115       nsCString pathHead("explicit/storage/sqlite/");
 116       // This filename isn't privacy-sensitive, and so is never anonymized.
 117       pathHead.Append(conn->getFilename());
 118       pathHead.Append('/');
 119
 120       SQLiteMutexAutoLock lockedScope(conn->sharedDBMutex);
 121
 122       constexpr auto stmtDesc =
 123           "Memory (approximate) used by all prepared statements used by "
 124           "connections to this database."_ns;
 125       ReportConn(aHandleReport, aData, conn, pathHead, "stmt"_ns, stmtDesc,
 126                  SQLITE_DBSTATUS_STMT_USED, &totalConnSize);
 127
 128       constexpr auto cacheDesc =
 129           "Memory (approximate) used by all pager caches used by connections "
 130           "to this database."_ns;
 131       ReportConn(aHandleReport, aData, conn, pathHead, "cache"_ns, cacheDesc,
 132                  SQLITE_DBSTATUS_CACHE_USED_SHARED, &totalConnSize);
 133
 134       constexpr auto schemaDesc =
 135           "Memory (approximate) used to store the schema for all databases "
 136           "associated with connections to this database."_ns;
 137       ReportConn(aHandleReport, aData, conn, pathHead, "schema"_ns, schemaDesc,
 138                  SQLITE_DBSTATUS_SCHEMA_USED, &totalConnSize);
 139     }
 140
 141 #ifdef MOZ_DMD
 142     if (::sqlite3_memory_used() != int64_t(gSqliteMemoryUsed)) {
 143       NS_WARNING(
 144           "memory consumption reported by SQLite doesn't match "
 145           "our measurements");
 146     }
 147 #endif
 148   }
 149
 150   int64_t other = ::sqlite3_memory_used() - totalConnSize;
 151
 152   MOZ_COLLECT_REPORT("explicit/storage/sqlite/other", KIND_HEAP, UNITS_BYTES,
 153                      other, "All unclassified sqlite memory.");
 154
 155   return NS_OK;
 156 }
 157
 158 ////////////////////////////////////////////////////////////////////////////////
 159 //// Service
 160
 161 NS_IMPL_ISUPPORTS(Service, mozIStorageService, nsIObserver, nsIMemoryReporter)
 162
 163 Service* Service::gService = nullptr;
 164
 165 already_AddRefed<Service> Service::getSingleton() {
 166   if (gService) {
 167     return do_AddRef(gService);
 168   }
 169
 170   // The first reference to the storage service must be obtained on the
 171   // main thread.
 172   NS_ENSURE_TRUE(NS_IsMainThread(), nullptr);
 173   RefPtr<Service> service = new Service();
 174   if (NS_SUCCEEDED(service->initialize())) {
 175     // Note: This is cleared in the Service destructor.
 176     gService = service.get();
 177     return service.forget();
 178   }
 179
 180   return nullptr;
 181 }
 182
 183 int Service::AutoVFSRegistration::Init(UniquePtr<sqlite3_vfs> aVFS) {
 184   MOZ_ASSERT(!mVFS);
 185   if (aVFS) {
 186     mVFS = std::move(aVFS);
 187     return sqlite3_vfs_register(mVFS.get(), 0);
 188   }
 189   NS_WARNING("Failed to register VFS");
 190   return SQLITE_OK;
 191 }
 192
 193 Service::AutoVFSRegistration::~AutoVFSRegistration() {
 194   if (mVFS) {
 195     int rc = sqlite3_vfs_unregister(mVFS.get());
 196     if (rc != SQLITE_OK) {
 197       NS_WARNING("Failed to unregister sqlite vfs wrapper.");
 198     }
 199   }
 200 }
 201
 202 Service::Service()
 203     : mMutex("Service::mMutex"),
 204       mRegistrationMutex("Service::mRegistrationMutex"),
 205       mConnections() {}
 206
 207 Service::~Service() {
 208   mozilla::UnregisterWeakMemoryReporter(this);
 209   mozilla::UnregisterStorageSQLiteDistinguishedAmount();
 210
 211   gService = nullptr;
 212 }
 213
 214 void Service::registerConnection(Connection* aConnection) {
 215   mRegistrationMutex.AssertNotCurrentThreadOwns();
 216   MutexAutoLock mutex(mRegistrationMutex);
 217   (void)mConnections.AppendElement(aConnection);
 218 }
 219
 220 void Service::unregisterConnection(Connection* aConnection) {
 221   // If this is the last Connection it might be the only thing keeping Service
 222   // alive.  So ensure that Service is destroyed only after the Connection is
 223   // cleanly unregistered and destroyed.
 224   RefPtr<Service> kungFuDeathGrip(this);
 225   RefPtr<Connection> forgettingRef;
 226   {
 227     mRegistrationMutex.AssertNotCurrentThreadOwns();
 228     MutexAutoLock mutex(mRegistrationMutex);
 229
 230     for (uint32_t i = 0; i < mConnections.Length(); ++i) {
 231       if (mConnections[i] == aConnection) {
 232         // Because dropping the final reference can potentially result in
 233         // spinning a nested event loop if the connection was not properly
 234         // shutdown, we want to do that outside this loop so that we can finish
 235         // mutating the array and drop our mutex.
 236         forgettingRef = std::move(mConnections[i]);
 237         mConnections.RemoveElementAt(i);
 238         break;
 239       }
 240     }
 241   }
 242
 243   MOZ_ASSERT(forgettingRef,
 244              "Attempt to unregister unknown storage connection!");
 245
 246   // Do not proxy the release anywhere, just let this reference drop here.  (We
 247   // previously did proxy the release, but that was because we invoked Close()
 248   // in the destructor and Close() likes to complain if it's not invoked on the
 249   // opener thread, so it was essential that the last reference be dropped on
 250   // the opener thread.  We now enqueue Close() inside our caller, Release(), so
 251   // it doesn't actually matter what thread our reference drops on.)
 252 }
 253
 254 void Service::getConnections(
 255     /* inout */ nsTArray<RefPtr<Connection>>& aConnections) {
 256   mRegistrationMutex.AssertNotCurrentThreadOwns();
 257   MutexAutoLock mutex(mRegistrationMutex);
 258   aConnections.Clear();
 259   aConnections.AppendElements(mConnections);
 260 }
 261
 262 void Service::minimizeMemory() {
 263   nsTArray<RefPtr<Connection>> connections;
 264   getConnections(connections);
 265
 266   for (uint32_t i = 0; i < connections.Length(); i++) {
 267     RefPtr<Connection> conn = connections[i];
 268     // For non-main-thread owning/opening threads, we may be racing against them
 269     // closing their connection or their thread.  That's okay, see below.
 270     if (!conn->connectionReady()) {
 271       continue;
 272     }
 273
 274     constexpr auto shrinkPragma = "PRAGMA shrink_memory"_ns;
 275     bool onOpenedThread = false;
 276
 277     if (!conn->operationSupported(Connection::SYNCHRONOUS)) {
 278       // This is a mozIStorageAsyncConnection, it can only be used on the main
 279       // thread, so we can do a straight API call.
 280       nsCOMPtr<mozIStoragePendingStatement> ps;
 281       DebugOnly<nsresult> rv = conn->ExecuteSimpleSQLAsync(
 282           shrinkPragma, nullptr, getter_AddRefs(ps));
 283       MOZ_ASSERT(NS_SUCCEEDED(rv), "Should have purged sqlite caches");
 284     } else if (NS_SUCCEEDED(
 285                    conn->threadOpenedOn->IsOnCurrentThread(&onOpenedThread)) &&
 286                onOpenedThread) {
 287       if (conn->isAsyncExecutionThreadAvailable()) {
 288         nsCOMPtr<mozIStoragePendingStatement> ps;
 289         DebugOnly<nsresult> rv = conn->ExecuteSimpleSQLAsync(
 290             shrinkPragma, nullptr, getter_AddRefs(ps));
 291         MOZ_ASSERT(NS_SUCCEEDED(rv), "Should have purged sqlite caches");
 292       } else {
 293         conn->ExecuteSimpleSQL(shrinkPragma);
 294       }
 295     } else {
 296       // We are on the wrong thread, the query should be executed on the
 297       // opener thread, so we must dispatch to it.
 298       // It's possible the connection is already closed or will be closed by the
 299       // time our runnable runs.  ExecuteSimpleSQL will safely return with a
 300       // failure in that case.  If the thread is shutting down or shut down, the
 301       // dispatch will fail and that's okay.
 302       nsCOMPtr<nsIRunnable> event = NewRunnableMethod<const nsCString>(
 303           "Connection::ExecuteSimpleSQL", conn, &Connection::ExecuteSimpleSQL,
 304           shrinkPragma);
 305       Unused << conn->threadOpenedOn->Dispatch(event, NS_DISPATCH_NORMAL);
 306     }
 307   }
 308 }
 309
 310 UniquePtr<sqlite3_vfs> ConstructTelemetryVFS(bool);
 311 const char* GetTelemetryVFSName(bool);
 312
 313 UniquePtr<sqlite3_vfs> ConstructObfuscatingVFS(const char* aBaseVFSName);
 314
 315 static const char* sObserverTopics[] = {"memory-pressure",
 316                                         "xpcom-shutdown-threads"};
 317
 318 nsresult Service::initialize() {
 319   MOZ_ASSERT(NS_IsMainThread(), "Must be initialized on the main thread");
 320
 321   int rc = AutoSQLiteLifetime::getInitResult();
 322   if (rc != SQLITE_OK) {
 323     return convertResultCode(rc);
 324   }
 325
 326   rc = mTelemetrySqliteVFS.Init(ConstructTelemetryVFS(false));
 327   if (rc != SQLITE_OK) {
 328     return convertResultCode(rc);
 329   }
 330
 331   rc = mTelemetryExclSqliteVFS.Init(ConstructTelemetryVFS(true));
 332   if (rc != SQLITE_OK) {
 333     return convertResultCode(rc);
 334   }
 335
 336   rc = mObfuscatingSqliteVFS.Init(ConstructObfuscatingVFS(GetTelemetryVFSName(
 337       StaticPrefs::storage_sqlite_exclusiveLock_enabled())));
 338   if (rc != SQLITE_OK) {
 339     return convertResultCode(rc);
 340   }
 341
 342   nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
 343   NS_ENSURE_TRUE(os, NS_ERROR_FAILURE);
 344
 345   for (size_t i = 0; i < ArrayLength(sObserverTopics); ++i) {
 346     nsresult rv = os->AddObserver(this, sObserverTopics[i], false);
 347     if (NS_WARN_IF(NS_FAILED(rv))) {
 348       return rv;
 349     }
 350   }
 351
 352   mozilla::RegisterWeakMemoryReporter(this);
 353   mozilla::RegisterStorageSQLiteDistinguishedAmount(
 354       StorageSQLiteDistinguishedAmount);
 355
 356   return NS_OK;
 357 }
 358
 359 int Service::localeCompareStrings(const nsAString& aStr1,
 360                                   const nsAString& aStr2,
 361                                   Collator::Sensitivity aSensitivity) {
 362   // The mozilla::intl::Collator is not thread safe, since the Collator::Options
 363   // can be changed.
 364   MutexAutoLock mutex(mMutex);
 365
 366   Collator* collator = getCollator();
 367   if (!collator) {
 368     NS_ERROR("Storage service has no collation");
 369     return 0;
 370   }
 371
 372   if (aSensitivity != mLastSensitivity) {
 373     Collator::Options options{};
 374     options.sensitivity = aSensitivity;
 375     auto result = mCollator->SetOptions(options);
 376
 377     if (result.isErr()) {
 378       NS_WARNING("Could not configure the mozilla::intl::Collation.");
 379       return 0;
 380     }
 381     mLastSensitivity = aSensitivity;
 382   }
 383
 384   return collator->CompareStrings(aStr1, aStr2);
 385 }
 386
 387 Collator* Service::getCollator() {
 388   mMutex.AssertCurrentThreadOwns();
 389
 390   if (mCollator) {
 391     return mCollator.get();
 392   }
 393
 394   auto result = mozilla::intl::LocaleService::TryCreateComponent<Collator>();
 395   if (result.isErr()) {
 396     NS_WARNING("Could not create mozilla::intl::Collation.");
 397     return nullptr;
 398   }
 399
 400   mCollator = result.unwrap();
 401
 402   // Sort in a case-insensitive way, where "base" letters are considered
 403   // equal, e.g: a = á, a = A, a ≠ b.
 404   Collator::Options options{};
 405   options.sensitivity = Collator::Sensitivity::Base;
 406   auto optResult = mCollator->SetOptions(options);
 407
 408   if (optResult.isErr()) {
 409     NS_WARNING("Could not configure the mozilla::intl::Collation.");
 410     mCollator = nullptr;
 411     return nullptr;
 412   }
 413
 414   return mCollator.get();
 415 }
 416
 417 ////////////////////////////////////////////////////////////////////////////////
 418 //// mozIStorageService
 419
 420 NS_IMETHODIMP
 421 Service::OpenSpecialDatabase(const nsACString& aStorageKey,
 422                              const nsACString& aName,
 423                              mozIStorageConnection** _connection) {
 424   if (!aStorageKey.Equals(kMozStorageMemoryStorageKey)) {
 425     return NS_ERROR_INVALID_ARG;
 426   }
 427
 428   int flags = SQLITE_OPEN_READWRITE;
 429
 430   if (!aName.IsEmpty()) {
 431     flags |= SQLITE_OPEN_URI;
 432   }
 433
 434   RefPtr<Connection> msc = new Connection(this, flags, Connection::SYNCHRONOUS);
 435
 436   nsresult rv = msc->initialize(aStorageKey, aName);
 437   NS_ENSURE_SUCCESS(rv, rv);
 438
 439   msc.forget(_connection);
 440   return NS_OK;
 441 }
 442
 443 namespace {
 444
 445 class AsyncInitDatabase final : public Runnable {
 446  public:
 447   AsyncInitDatabase(Connection* aConnection, nsIFile* aStorageFile,
 448                     int32_t aGrowthIncrement,
 449                     mozIStorageCompletionCallback* aCallback)
 450       : Runnable("storage::AsyncInitDatabase"),
 451         mConnection(aConnection),
 452         mStorageFile(aStorageFile),
 453         mGrowthIncrement(aGrowthIncrement),
 454         mCallback(aCallback) {
 455     MOZ_ASSERT(NS_IsMainThread());
 456   }
 457
 458   NS_IMETHOD Run() override {
 459     MOZ_ASSERT(!NS_IsMainThread());
 460     nsresult rv = mConnection->initializeOnAsyncThread(mStorageFile);
 461     if (NS_FAILED(rv)) {
 462       return DispatchResult(rv, nullptr);
 463     }
 464
 465     if (mGrowthIncrement >= 0) {
 466       // Ignore errors. In the future, we might wish to log them.
 467       (void)mConnection->SetGrowthIncrement(mGrowthIncrement, ""_ns);
 468     }
 469
 470     return DispatchResult(
 471         NS_OK, NS_ISUPPORTS_CAST(mozIStorageAsyncConnection*, mConnection));
 472   }
 473
 474  private:
 475   nsresult DispatchResult(nsresult aStatus, nsISupports* aValue) {
 476     RefPtr<CallbackComplete> event =
 477         new CallbackComplete(aStatus, aValue, mCallback.forget());
 478     return NS_DispatchToMainThread(event);
 479   }
 480
 481   ~AsyncInitDatabase() {
 482     NS_ReleaseOnMainThread("AsyncInitDatabase::mStorageFile",
 483                            mStorageFile.forget());
 484     NS_ReleaseOnMainThread("AsyncInitDatabase::mConnection",
 485                            mConnection.forget());
 486
 487     // Generally, the callback will be released by CallbackComplete.
 488     // However, if for some reason Run() is not executed, we still
 489     // need to ensure that it is released here.
 490     NS_ReleaseOnMainThread("AsyncInitDatabase::mCallback", mCallback.forget());
 491   }
 492
 493   RefPtr<Connection> mConnection;
 494   nsCOMPtr<nsIFile> mStorageFile;
 495   int32_t mGrowthIncrement;
 496   RefPtr<mozIStorageCompletionCallback> mCallback;
 497 };
 498
 499 }  // namespace
 500
 501 NS_IMETHODIMP
 502 Service::OpenAsyncDatabase(nsIVariant* aDatabaseStore,
 503                            nsIPropertyBag2* aOptions,
 504                            mozIStorageCompletionCallback* aCallback) {
 505   if (!NS_IsMainThread()) {
 506     return NS_ERROR_NOT_SAME_THREAD;
 507   }
 508   NS_ENSURE_ARG(aDatabaseStore);
 509   NS_ENSURE_ARG(aCallback);
 510
 511   nsresult rv;
 512   bool shared = false;
 513   bool readOnly = false;
 514   bool ignoreLockingMode = false;
 515   int32_t growthIncrement = -1;
 516
 517 #define FAIL_IF_SET_BUT_INVALID(rv)                    \
 518   if (NS_FAILED(rv) && rv != NS_ERROR_NOT_AVAILABLE) { \
 519     return NS_ERROR_INVALID_ARG;                       \
 520   }
 521
 522   // Deal with options first:
 523   if (aOptions) {
 524     rv = aOptions->GetPropertyAsBool(u"readOnly"_ns, &readOnly);
 525     FAIL_IF_SET_BUT_INVALID(rv);
 526
 527     rv = aOptions->GetPropertyAsBool(u"ignoreLockingMode"_ns,
 528                                      &ignoreLockingMode);
 529     FAIL_IF_SET_BUT_INVALID(rv);
 530     // Specifying ignoreLockingMode will force use of the readOnly flag:
 531     if (ignoreLockingMode) {
 532       readOnly = true;
 533     }
 534
 535     rv = aOptions->GetPropertyAsBool(u"shared"_ns, &shared);
 536     FAIL_IF_SET_BUT_INVALID(rv);
 537
 538     // NB: we re-set to -1 if we don't have a storage file later on.
 539     rv = aOptions->GetPropertyAsInt32(u"growthIncrement"_ns, &growthIncrement);
 540     FAIL_IF_SET_BUT_INVALID(rv);
 541   }
 542   int flags = readOnly ? SQLITE_OPEN_READONLY : SQLITE_OPEN_READWRITE;
 543
 544   nsCOMPtr<nsIFile> storageFile;
 545   nsCOMPtr<nsISupports> dbStore;
 546   rv = aDatabaseStore->GetAsISupports(getter_AddRefs(dbStore));
 547   if (NS_SUCCEEDED(rv)) {
 548     // Generally, aDatabaseStore holds the database nsIFile.
 549     storageFile = do_QueryInterface(dbStore, &rv);
 550     if (NS_FAILED(rv)) {
 551       return NS_ERROR_INVALID_ARG;
 552     }
 553
 554     nsCOMPtr<nsIFile> cloned;
 555     rv = storageFile->Clone(getter_AddRefs(cloned));
 556     MOZ_ASSERT(NS_SUCCEEDED(rv));
 557     storageFile = std::move(cloned);
 558
 559     if (!readOnly) {
 560       // Ensure that SQLITE_OPEN_CREATE is passed in for compatibility reasons.
 561       flags |= SQLITE_OPEN_CREATE;
 562     }
 563
 564     // Apply the shared-cache option.
 565     flags |= shared ? SQLITE_OPEN_SHAREDCACHE : SQLITE_OPEN_PRIVATECACHE;
 566   } else {
 567     // Sometimes, however, it's a special database name.
 568     nsAutoCString keyString;
 569     rv = aDatabaseStore->GetAsACString(keyString);
 570     if (NS_FAILED(rv) || !keyString.Equals(kMozStorageMemoryStorageKey)) {
 571       return NS_ERROR_INVALID_ARG;
 572     }
 573
 574     // Just fall through with nullptr storageFile, this will cause the storage
 575     // connection to use a memory DB.
 576   }
 577
 578   if (!storageFile && growthIncrement >= 0) {
 579     return NS_ERROR_INVALID_ARG;
 580   }
 581
 582   // Create connection on this thread, but initialize it on its helper thread.
 583   RefPtr<Connection> msc =
 584       new Connection(this, flags, Connection::ASYNCHRONOUS, ignoreLockingMode);
 585   nsCOMPtr<nsIEventTarget> target = msc->getAsyncExecutionTarget();
 586   MOZ_ASSERT(target,
 587              "Cannot initialize a connection that has been closed already");
 588
 589   RefPtr<AsyncInitDatabase> asyncInit =
 590       new AsyncInitDatabase(msc, storageFile, growthIncrement, aCallback);
 591   return target->Dispatch(asyncInit, nsIEventTarget::DISPATCH_NORMAL);
 592 }
 593
 594 NS_IMETHODIMP
 595 Service::OpenDatabase(nsIFile* aDatabaseFile,
 596                       mozIStorageConnection** _connection) {
 597   NS_ENSURE_ARG(aDatabaseFile);
 598
 599   // Always ensure that SQLITE_OPEN_CREATE is passed in for compatibility
 600   // reasons.
 601   int flags =
 602       SQLITE_OPEN_READWRITE | SQLITE_OPEN_SHAREDCACHE | SQLITE_OPEN_CREATE;
 603   RefPtr<Connection> msc = new Connection(this, flags, Connection::SYNCHRONOUS);
 604
 605   nsresult rv = msc->initialize(aDatabaseFile);
 606   NS_ENSURE_SUCCESS(rv, rv);
 607
 608   msc.forget(_connection);
 609   return NS_OK;
 610 }
 611
 612 NS_IMETHODIMP
 613 Service::OpenUnsharedDatabase(nsIFile* aDatabaseFile,
 614                               mozIStorageConnection** _connection) {
 615   NS_ENSURE_ARG(aDatabaseFile);
 616
 617   // Always ensure that SQLITE_OPEN_CREATE is passed in for compatibility
 618   // reasons.
 619   int flags =
 620       SQLITE_OPEN_READWRITE | SQLITE_OPEN_PRIVATECACHE | SQLITE_OPEN_CREATE;
 621   RefPtr<Connection> msc = new Connection(this, flags, Connection::SYNCHRONOUS);
 622
 623   nsresult rv = msc->initialize(aDatabaseFile);
 624   NS_ENSURE_SUCCESS(rv, rv);
 625
 626   msc.forget(_connection);
 627   return NS_OK;
 628 }
 629
 630 NS_IMETHODIMP
 631 Service::OpenDatabaseWithFileURL(nsIFileURL* aFileURL,
 632                                  const nsACString& aTelemetryFilename,
 633                                  mozIStorageConnection** _connection) {
 634   NS_ENSURE_ARG(aFileURL);
 635
 636   // Always ensure that SQLITE_OPEN_CREATE is passed in for compatibility
 637   // reasons.
 638   int flags = SQLITE_OPEN_READWRITE | SQLITE_OPEN_SHAREDCACHE |
 639               SQLITE_OPEN_CREATE | SQLITE_OPEN_URI;
 640   RefPtr<Connection> msc = new Connection(this, flags, Connection::SYNCHRONOUS);
 641
 642   nsresult rv = msc->initialize(aFileURL, aTelemetryFilename);
 643   NS_ENSURE_SUCCESS(rv, rv);
 644
 645   msc.forget(_connection);
 646   return NS_OK;
 647 }
 648
 649 NS_IMETHODIMP
 650 Service::BackupDatabaseFile(nsIFile* aDBFile, const nsAString& aBackupFileName,
 651                             nsIFile* aBackupParentDirectory, nsIFile** backup) {
 652   nsresult rv;
 653   nsCOMPtr<nsIFile> parentDir = aBackupParentDirectory;
 654   if (!parentDir) {
 655     // This argument is optional, and defaults to the same parent directory
 656     // as the current file.
 657     rv = aDBFile->GetParent(getter_AddRefs(parentDir));
 658     NS_ENSURE_SUCCESS(rv, rv);
 659   }
 660
 661   nsCOMPtr<nsIFile> backupDB;
 662   rv = parentDir->Clone(getter_AddRefs(backupDB));
 663   NS_ENSURE_SUCCESS(rv, rv);
 664
 665   rv = backupDB->Append(aBackupFileName);
 666   NS_ENSURE_SUCCESS(rv, rv);
 667
 668   rv = backupDB->CreateUnique(nsIFile::NORMAL_FILE_TYPE, 0600);
 669   NS_ENSURE_SUCCESS(rv, rv);
 670
 671   nsAutoString fileName;
 672   rv = backupDB->GetLeafName(fileName);
 673   NS_ENSURE_SUCCESS(rv, rv);
 674
 675   rv = backupDB->Remove(false);
 676   NS_ENSURE_SUCCESS(rv, rv);
 677
 678   backupDB.forget(backup);
 679
 680   return aDBFile->CopyTo(parentDir, fileName);
 681 }
 682
 683 ////////////////////////////////////////////////////////////////////////////////
 684 //// nsIObserver
 685
 686 NS_IMETHODIMP
 687 Service::Observe(nsISupports*, const char* aTopic, const char16_t*) {
 688   if (strcmp(aTopic, "memory-pressure") == 0) {
 689     minimizeMemory();
 690   } else if (strcmp(aTopic, "xpcom-shutdown-threads") == 0) {
 691     // The Service is kept alive by our strong observer references and
 692     // references held by Connection instances.  Since we're about to remove the
 693     // former and then wait for the latter ones to go away, it behooves us to
 694     // hold a strong reference to ourselves so our calls to getConnections() do
 695     // not happen on a deleted object.
 696     RefPtr<Service> kungFuDeathGrip = this;
 697
 698     nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
 699
 700     for (size_t i = 0; i < ArrayLength(sObserverTopics); ++i) {
 701       (void)os->RemoveObserver(this, sObserverTopics[i]);
 702     }
 703
 704     SpinEventLoopUntil([&]() -> bool {
 705       // We must wait until all the closing connections are closed.
 706       nsTArray<RefPtr<Connection>> connections;
 707       getConnections(connections);
 708       for (auto& conn : connections) {
 709         if (conn->isClosing()) {
 710           return false;
 711         }
 712       }
 713       return true;
 714     });
 715
 716 #ifdef DEBUG
 717     nsTArray<RefPtr<Connection>> connections;
 718     getConnections(connections);
 719     for (uint32_t i = 0, n = connections.Length(); i < n; i++) {
 720       if (!connections[i]->isClosed()) {
 721         // getFilename is only the leaf name for the database file,
 722         // so it shouldn't contain privacy-sensitive information.
 723         CrashReporter::AnnotateCrashReport(
 724             CrashReporter::Annotation::StorageConnectionNotClosed,
 725             connections[i]->getFilename());
 726         printf_stderr("Storage connection not closed: %s",
 727                       connections[i]->getFilename().get());
 728         MOZ_CRASH();
 729       }
 730     }
 731 #endif
 732   }
 733
 734   return NS_OK;
 735 }
 736
 737 }  // namespace storage
 738 }  // namespace mozilla