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 event target, so it was essential that the last reference be dropped
 250   // on the opener event target.  We now enqueue Close() inside our caller,
 251   // Release(), so it doesn't actually matter what thread our reference drops
 252   // on.)
 253 }
 254
 255 void Service::getConnections(
 256     /* inout */ nsTArray<RefPtr<Connection>>& aConnections) {
 257   mRegistrationMutex.AssertNotCurrentThreadOwns();
 258   MutexAutoLock mutex(mRegistrationMutex);
 259   aConnections.Clear();
 260   aConnections.AppendElements(mConnections);
 261 }
 262
 263 void Service::minimizeMemory() {
 264   nsTArray<RefPtr<Connection>> connections;
 265   getConnections(connections);
 266
 267   for (uint32_t i = 0; i < connections.Length(); i++) {
 268     RefPtr<Connection> conn = connections[i];
 269     // For non-main-thread owning/opening threads, we may be racing against them
 270     // closing their connection or their thread.  That's okay, see below.
 271     if (!conn->connectionReady()) {
 272       continue;
 273     }
 274
 275     constexpr auto shrinkPragma = "PRAGMA shrink_memory"_ns;
 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 (IsOnCurrentSerialEventTarget(conn->eventTargetOpenedOn)) {
 285       if (conn->isAsyncExecutionThreadAvailable()) {
 286         nsCOMPtr<mozIStoragePendingStatement> ps;
 287         DebugOnly<nsresult> rv = conn->ExecuteSimpleSQLAsync(
 288             shrinkPragma, nullptr, getter_AddRefs(ps));
 289         MOZ_ASSERT(NS_SUCCEEDED(rv), "Should have purged sqlite caches");
 290       } else {
 291         conn->ExecuteSimpleSQL(shrinkPragma);
 292       }
 293     } else {
 294       // We are on the wrong event target, the query should be executed on the
 295       // opener event target, so we must dispatch to it.
 296       // It's possible the connection is already closed or will be closed by the
 297       // time our runnable runs. ExecuteSimpleSQL will safely return with a
 298       // failure in that case. If the event target is shutting down or shut
 299       // down, the dispatch will fail and that's okay.
 300       nsCOMPtr<nsIRunnable> event = NewRunnableMethod<const nsCString>(
 301           "Connection::ExecuteSimpleSQL", conn, &Connection::ExecuteSimpleSQL,
 302           shrinkPragma);
 303       Unused << conn->eventTargetOpenedOn->Dispatch(event, NS_DISPATCH_NORMAL);
 304     }
 305   }
 306 }
 307
 308 UniquePtr<sqlite3_vfs> ConstructTelemetryVFS(bool);
 309 const char* GetTelemetryVFSName(bool);
 310
 311 UniquePtr<sqlite3_vfs> ConstructObfuscatingVFS(const char* aBaseVFSName);
 312
 313 static const char* sObserverTopics[] = {"memory-pressure",
 314                                         "xpcom-shutdown-threads"};
 315
 316 nsresult Service::initialize() {
 317   MOZ_ASSERT(NS_IsMainThread(), "Must be initialized on the main thread");
 318
 319   int rc = AutoSQLiteLifetime::getInitResult();
 320   if (rc != SQLITE_OK) {
 321     return convertResultCode(rc);
 322   }
 323
 324   rc = mTelemetrySqliteVFS.Init(ConstructTelemetryVFS(false));
 325   if (rc != SQLITE_OK) {
 326     return convertResultCode(rc);
 327   }
 328
 329   rc = mTelemetryExclSqliteVFS.Init(ConstructTelemetryVFS(true));
 330   if (rc != SQLITE_OK) {
 331     return convertResultCode(rc);
 332   }
 333
 334   rc = mObfuscatingSqliteVFS.Init(ConstructObfuscatingVFS(GetTelemetryVFSName(
 335       StaticPrefs::storage_sqlite_exclusiveLock_enabled())));
 336   if (rc != SQLITE_OK) {
 337     return convertResultCode(rc);
 338   }
 339
 340   nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
 341   NS_ENSURE_TRUE(os, NS_ERROR_FAILURE);
 342
 343   for (size_t i = 0; i < ArrayLength(sObserverTopics); ++i) {
 344     nsresult rv = os->AddObserver(this, sObserverTopics[i], false);
 345     if (NS_WARN_IF(NS_FAILED(rv))) {
 346       return rv;
 347     }
 348   }
 349
 350   mozilla::RegisterWeakMemoryReporter(this);
 351   mozilla::RegisterStorageSQLiteDistinguishedAmount(
 352       StorageSQLiteDistinguishedAmount);
 353
 354   return NS_OK;
 355 }
 356
 357 int Service::localeCompareStrings(const nsAString& aStr1,
 358                                   const nsAString& aStr2,
 359                                   Collator::Sensitivity aSensitivity) {
 360   // The mozilla::intl::Collator is not thread safe, since the Collator::Options
 361   // can be changed.
 362   MutexAutoLock mutex(mMutex);
 363
 364   Collator* collator = getCollator();
 365   if (!collator) {
 366     NS_ERROR("Storage service has no collation");
 367     return 0;
 368   }
 369
 370   if (aSensitivity != mLastSensitivity) {
 371     Collator::Options options{};
 372     options.sensitivity = aSensitivity;
 373     auto result = mCollator->SetOptions(options);
 374
 375     if (result.isErr()) {
 376       NS_WARNING("Could not configure the mozilla::intl::Collation.");
 377       return 0;
 378     }
 379     mLastSensitivity = aSensitivity;
 380   }
 381
 382   return collator->CompareStrings(aStr1, aStr2);
 383 }
 384
 385 Collator* Service::getCollator() {
 386   mMutex.AssertCurrentThreadOwns();
 387
 388   if (mCollator) {
 389     return mCollator.get();
 390   }
 391
 392   auto result = mozilla::intl::LocaleService::TryCreateComponent<Collator>();
 393   if (result.isErr()) {
 394     NS_WARNING("Could not create mozilla::intl::Collation.");
 395     return nullptr;
 396   }
 397
 398   mCollator = result.unwrap();
 399
 400   // Sort in a case-insensitive way, where "base" letters are considered
 401   // equal, e.g: a = á, a = A, a ≠ b.
 402   Collator::Options options{};
 403   options.sensitivity = Collator::Sensitivity::Base;
 404   auto optResult = mCollator->SetOptions(options);
 405
 406   if (optResult.isErr()) {
 407     NS_WARNING("Could not configure the mozilla::intl::Collation.");
 408     mCollator = nullptr;
 409     return nullptr;
 410   }
 411
 412   return mCollator.get();
 413 }
 414
 415 ////////////////////////////////////////////////////////////////////////////////
 416 //// mozIStorageService
 417
 418 NS_IMETHODIMP
 419 Service::OpenSpecialDatabase(const nsACString& aStorageKey,
 420                              const nsACString& aName, uint32_t aConnectionFlags,
 421                              mozIStorageConnection** _connection) {
 422   if (!aStorageKey.Equals(kMozStorageMemoryStorageKey)) {
 423     return NS_ERROR_INVALID_ARG;
 424   }
 425
 426   const bool interruptible =
 427       aConnectionFlags & mozIStorageService::CONNECTION_INTERRUPTIBLE;
 428
 429   int flags = SQLITE_OPEN_READWRITE;
 430
 431   if (!aName.IsEmpty()) {
 432     flags |= SQLITE_OPEN_URI;
 433   }
 434
 435   RefPtr<Connection> msc =
 436       new Connection(this, flags, Connection::SYNCHRONOUS, interruptible);
 437
 438   const nsresult rv = msc->initialize(aStorageKey, aName);
 439   NS_ENSURE_SUCCESS(rv, rv);
 440
 441   msc.forget(_connection);
 442   return NS_OK;
 443 }
 444
 445 namespace {
 446
 447 class AsyncInitDatabase final : public Runnable {
 448  public:
 449   AsyncInitDatabase(Connection* aConnection, nsIFile* aStorageFile,
 450                     int32_t aGrowthIncrement,
 451                     mozIStorageCompletionCallback* aCallback)
 452       : Runnable("storage::AsyncInitDatabase"),
 453         mConnection(aConnection),
 454         mStorageFile(aStorageFile),
 455         mGrowthIncrement(aGrowthIncrement),
 456         mCallback(aCallback) {
 457     MOZ_ASSERT(NS_IsMainThread());
 458   }
 459
 460   NS_IMETHOD Run() override {
 461     MOZ_ASSERT(!NS_IsMainThread());
 462     nsresult rv = mConnection->initializeOnAsyncThread(mStorageFile);
 463     if (NS_FAILED(rv)) {
 464       return DispatchResult(rv, nullptr);
 465     }
 466
 467     if (mGrowthIncrement >= 0) {
 468       // Ignore errors. In the future, we might wish to log them.
 469       (void)mConnection->SetGrowthIncrement(mGrowthIncrement, ""_ns);
 470     }
 471
 472     return DispatchResult(
 473         NS_OK, NS_ISUPPORTS_CAST(mozIStorageAsyncConnection*, mConnection));
 474   }
 475
 476  private:
 477   nsresult DispatchResult(nsresult aStatus, nsISupports* aValue) {
 478     RefPtr<CallbackComplete> event =
 479         new CallbackComplete(aStatus, aValue, mCallback.forget());
 480     return NS_DispatchToMainThread(event);
 481   }
 482
 483   ~AsyncInitDatabase() {
 484     NS_ReleaseOnMainThread("AsyncInitDatabase::mStorageFile",
 485                            mStorageFile.forget());
 486     NS_ReleaseOnMainThread("AsyncInitDatabase::mConnection",
 487                            mConnection.forget());
 488
 489     // Generally, the callback will be released by CallbackComplete.
 490     // However, if for some reason Run() is not executed, we still
 491     // need to ensure that it is released here.
 492     NS_ReleaseOnMainThread("AsyncInitDatabase::mCallback", mCallback.forget());
 493   }
 494
 495   RefPtr<Connection> mConnection;
 496   nsCOMPtr<nsIFile> mStorageFile;
 497   int32_t mGrowthIncrement;
 498   RefPtr<mozIStorageCompletionCallback> mCallback;
 499 };
 500
 501 }  // namespace
 502
 503 NS_IMETHODIMP
 504 Service::OpenAsyncDatabase(nsIVariant* aDatabaseStore, uint32_t aOpenFlags,
 505                            uint32_t /* aConnectionFlags */,
 506                            mozIStorageCompletionCallback* aCallback) {
 507   if (!NS_IsMainThread()) {
 508     return NS_ERROR_NOT_SAME_THREAD;
 509   }
 510   NS_ENSURE_ARG(aDatabaseStore);
 511   NS_ENSURE_ARG(aCallback);
 512
 513   const bool shared = aOpenFlags & mozIStorageService::OPEN_SHARED;
 514   const bool ignoreLockingMode =
 515       aOpenFlags & mozIStorageService::OPEN_IGNORE_LOCKING_MODE;
 516   // Specifying ignoreLockingMode will force use of the readOnly flag:
 517   const bool readOnly =
 518       ignoreLockingMode || (aOpenFlags & mozIStorageService::OPEN_READONLY);
 519   int flags = readOnly ? SQLITE_OPEN_READONLY : SQLITE_OPEN_READWRITE;
 520
 521   nsCOMPtr<nsIFile> storageFile;
 522   nsCOMPtr<nsISupports> dbStore;
 523   nsresult rv = aDatabaseStore->GetAsISupports(getter_AddRefs(dbStore));
 524   if (NS_SUCCEEDED(rv)) {
 525     // Generally, aDatabaseStore holds the database nsIFile.
 526     storageFile = do_QueryInterface(dbStore, &rv);
 527     if (NS_FAILED(rv)) {
 528       return NS_ERROR_INVALID_ARG;
 529     }
 530
 531     nsCOMPtr<nsIFile> cloned;
 532     rv = storageFile->Clone(getter_AddRefs(cloned));
 533     MOZ_ASSERT(NS_SUCCEEDED(rv));
 534     storageFile = std::move(cloned);
 535
 536     if (!readOnly) {
 537       // Ensure that SQLITE_OPEN_CREATE is passed in for compatibility reasons.
 538       flags |= SQLITE_OPEN_CREATE;
 539     }
 540
 541     // Apply the shared-cache option.
 542     flags |= shared ? SQLITE_OPEN_SHAREDCACHE : SQLITE_OPEN_PRIVATECACHE;
 543   } else {
 544     // Sometimes, however, it's a special database name.
 545     nsAutoCString keyString;
 546     rv = aDatabaseStore->GetAsACString(keyString);
 547     if (NS_FAILED(rv) || !keyString.Equals(kMozStorageMemoryStorageKey)) {
 548       return NS_ERROR_INVALID_ARG;
 549     }
 550
 551     // Just fall through with nullptr storageFile, this will cause the storage
 552     // connection to use a memory DB.
 553   }
 554
 555   // Create connection on this thread, but initialize it on its helper thread.
 556   RefPtr<Connection> msc =
 557       new Connection(this, flags, Connection::ASYNCHRONOUS,
 558                      /* interruptible */ true, ignoreLockingMode);
 559   nsCOMPtr<nsIEventTarget> target = msc->getAsyncExecutionTarget();
 560   MOZ_ASSERT(target,
 561              "Cannot initialize a connection that has been closed already");
 562
 563   RefPtr<AsyncInitDatabase> asyncInit = new AsyncInitDatabase(
 564       msc, storageFile, /* growthIncrement */ -1, aCallback);
 565   return target->Dispatch(asyncInit, nsIEventTarget::DISPATCH_NORMAL);
 566 }
 567
 568 NS_IMETHODIMP
 569 Service::OpenDatabase(nsIFile* aDatabaseFile, uint32_t aConnectionFlags,
 570                       mozIStorageConnection** _connection) {
 571   NS_ENSURE_ARG(aDatabaseFile);
 572
 573   const bool interruptible =
 574       aConnectionFlags & mozIStorageService::CONNECTION_INTERRUPTIBLE;
 575
 576   // Always ensure that SQLITE_OPEN_CREATE is passed in for compatibility
 577   // reasons.
 578   const int flags =
 579       SQLITE_OPEN_READWRITE | SQLITE_OPEN_SHAREDCACHE | SQLITE_OPEN_CREATE;
 580   RefPtr<Connection> msc =
 581       new Connection(this, flags, Connection::SYNCHRONOUS, interruptible);
 582
 583   const nsresult rv = msc->initialize(aDatabaseFile);
 584   NS_ENSURE_SUCCESS(rv, rv);
 585
 586   msc.forget(_connection);
 587   return NS_OK;
 588 }
 589
 590 NS_IMETHODIMP
 591 Service::OpenUnsharedDatabase(nsIFile* aDatabaseFile, uint32_t aConnectionFlags,
 592                               mozIStorageConnection** _connection) {
 593   NS_ENSURE_ARG(aDatabaseFile);
 594
 595   const bool interruptible =
 596       aConnectionFlags & mozIStorageService::CONNECTION_INTERRUPTIBLE;
 597
 598   // Always ensure that SQLITE_OPEN_CREATE is passed in for compatibility
 599   // reasons.
 600   const int flags =
 601       SQLITE_OPEN_READWRITE | SQLITE_OPEN_PRIVATECACHE | SQLITE_OPEN_CREATE;
 602   RefPtr<Connection> msc =
 603       new Connection(this, flags, Connection::SYNCHRONOUS, interruptible);
 604
 605   const 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::OpenDatabaseWithFileURL(nsIFileURL* aFileURL,
 614                                  const nsACString& aTelemetryFilename,
 615                                  uint32_t aConnectionFlags,
 616                                  mozIStorageConnection** _connection) {
 617   NS_ENSURE_ARG(aFileURL);
 618
 619   const bool interruptible =
 620       aConnectionFlags & mozIStorageService::CONNECTION_INTERRUPTIBLE;
 621
 622   // Always ensure that SQLITE_OPEN_CREATE is passed in for compatibility
 623   // reasons.
 624   const int flags = SQLITE_OPEN_READWRITE | SQLITE_OPEN_SHAREDCACHE |
 625                     SQLITE_OPEN_CREATE | SQLITE_OPEN_URI;
 626   RefPtr<Connection> msc =
 627       new Connection(this, flags, Connection::SYNCHRONOUS, interruptible);
 628
 629   const nsresult rv = msc->initialize(aFileURL, aTelemetryFilename);
 630   NS_ENSURE_SUCCESS(rv, rv);
 631
 632   msc.forget(_connection);
 633   return NS_OK;
 634 }
 635
 636 NS_IMETHODIMP
 637 Service::BackupDatabaseFile(nsIFile* aDBFile, const nsAString& aBackupFileName,
 638                             nsIFile* aBackupParentDirectory, nsIFile** backup) {
 639   nsresult rv;
 640   nsCOMPtr<nsIFile> parentDir = aBackupParentDirectory;
 641   if (!parentDir) {
 642     // This argument is optional, and defaults to the same parent directory
 643     // as the current file.
 644     rv = aDBFile->GetParent(getter_AddRefs(parentDir));
 645     NS_ENSURE_SUCCESS(rv, rv);
 646   }
 647
 648   nsCOMPtr<nsIFile> backupDB;
 649   rv = parentDir->Clone(getter_AddRefs(backupDB));
 650   NS_ENSURE_SUCCESS(rv, rv);
 651
 652   rv = backupDB->Append(aBackupFileName);
 653   NS_ENSURE_SUCCESS(rv, rv);
 654
 655   rv = backupDB->CreateUnique(nsIFile::NORMAL_FILE_TYPE, 0600);
 656   NS_ENSURE_SUCCESS(rv, rv);
 657
 658   nsAutoString fileName;
 659   rv = backupDB->GetLeafName(fileName);
 660   NS_ENSURE_SUCCESS(rv, rv);
 661
 662   rv = backupDB->Remove(false);
 663   NS_ENSURE_SUCCESS(rv, rv);
 664
 665   backupDB.forget(backup);
 666
 667   return aDBFile->CopyTo(parentDir, fileName);
 668 }
 669
 670 ////////////////////////////////////////////////////////////////////////////////
 671 //// nsIObserver
 672
 673 NS_IMETHODIMP
 674 Service::Observe(nsISupports*, const char* aTopic, const char16_t*) {
 675   if (strcmp(aTopic, "memory-pressure") == 0) {
 676     minimizeMemory();
 677   } else if (strcmp(aTopic, "xpcom-shutdown-threads") == 0) {
 678     // The Service is kept alive by our strong observer references and
 679     // references held by Connection instances.  Since we're about to remove the
 680     // former and then wait for the latter ones to go away, it behooves us to
 681     // hold a strong reference to ourselves so our calls to getConnections() do
 682     // not happen on a deleted object.
 683     RefPtr<Service> kungFuDeathGrip = this;
 684
 685     nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
 686
 687     for (size_t i = 0; i < ArrayLength(sObserverTopics); ++i) {
 688       (void)os->RemoveObserver(this, sObserverTopics[i]);
 689     }
 690
 691     SpinEventLoopUntil("storage::Service::Observe(xpcom-shutdown-threads)"_ns,
 692                        [&]() -> bool {
 693                          // We must wait until all the closing connections are
 694                          // closed.
 695                          nsTArray<RefPtr<Connection>> connections;
 696                          getConnections(connections);
 697                          for (auto& conn : connections) {
 698                            if (conn->isClosing()) {
 699                              return false;
 700                            }
 701                          }
 702                          return true;
 703                        });
 704
 705 #ifdef DEBUG
 706     nsTArray<RefPtr<Connection>> connections;
 707     getConnections(connections);
 708     for (uint32_t i = 0, n = connections.Length(); i < n; i++) {
 709       if (!connections[i]->isClosed()) {
 710         // getFilename is only the leaf name for the database file,
 711         // so it shouldn't contain privacy-sensitive information.
 712         CrashReporter::AnnotateCrashReport(
 713             CrashReporter::Annotation::StorageConnectionNotClosed,
 714             connections[i]->getFilename());
 715         printf_stderr("Storage connection not closed: %s",
 716                       connections[i]->getFilename().get());
 717         MOZ_CRASH();
 718       }
 719     }
 720 #endif
 721   }
 722
 723   return NS_OK;
 724 }
 725
 726 }  // namespace storage
 727 }  // namespace mozilla