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 UniquePtr<sqlite3_vfs> ConstructReadOnlyNoLockVFS();
 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   rc = mReadOnlyNoLockSqliteVFS.Init(ConstructReadOnlyNoLockVFS());
 343   if (rc != SQLITE_OK) {
 344     return convertResultCode(rc);
 345   }
 346
 347   nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
 348   NS_ENSURE_TRUE(os, NS_ERROR_FAILURE);
 349
 350   for (size_t i = 0; i < ArrayLength(sObserverTopics); ++i) {
 351     nsresult rv = os->AddObserver(this, sObserverTopics[i], false);
 352     if (NS_WARN_IF(NS_FAILED(rv))) {
 353       return rv;
 354     }
 355   }
 356
 357   mozilla::RegisterWeakMemoryReporter(this);
 358   mozilla::RegisterStorageSQLiteDistinguishedAmount(
 359       StorageSQLiteDistinguishedAmount);
 360
 361   return NS_OK;
 362 }
 363
 364 int Service::localeCompareStrings(const nsAString& aStr1,
 365                                   const nsAString& aStr2,
 366                                   Collator::Sensitivity aSensitivity) {
 367   // The mozilla::intl::Collator is not thread safe, since the Collator::Options
 368   // can be changed.
 369   MutexAutoLock mutex(mMutex);
 370
 371   Collator* collator = getCollator();
 372   if (!collator) {
 373     NS_ERROR("Storage service has no collation");
 374     return 0;
 375   }
 376
 377   if (aSensitivity != mLastSensitivity) {
 378     Collator::Options options{};
 379     options.sensitivity = aSensitivity;
 380     auto result = mCollator->SetOptions(options);
 381
 382     if (result.isErr()) {
 383       NS_WARNING("Could not configure the mozilla::intl::Collation.");
 384       return 0;
 385     }
 386     mLastSensitivity = aSensitivity;
 387   }
 388
 389   return collator->CompareStrings(aStr1, aStr2);
 390 }
 391
 392 Collator* Service::getCollator() {
 393   mMutex.AssertCurrentThreadOwns();
 394
 395   if (mCollator) {
 396     return mCollator.get();
 397   }
 398
 399   auto result = mozilla::intl::LocaleService::TryCreateComponent<Collator>();
 400   if (result.isErr()) {
 401     NS_WARNING("Could not create mozilla::intl::Collation.");
 402     return nullptr;
 403   }
 404
 405   mCollator = result.unwrap();
 406
 407   // Sort in a case-insensitive way, where "base" letters are considered
 408   // equal, e.g: a = á, a = A, a ≠ b.
 409   Collator::Options options{};
 410   options.sensitivity = Collator::Sensitivity::Base;
 411   auto optResult = mCollator->SetOptions(options);
 412
 413   if (optResult.isErr()) {
 414     NS_WARNING("Could not configure the mozilla::intl::Collation.");
 415     mCollator = nullptr;
 416     return nullptr;
 417   }
 418
 419   return mCollator.get();
 420 }
 421
 422 ////////////////////////////////////////////////////////////////////////////////
 423 //// mozIStorageService
 424
 425 NS_IMETHODIMP
 426 Service::OpenSpecialDatabase(const nsACString& aStorageKey,
 427                              const nsACString& aName, uint32_t aConnectionFlags,
 428                              mozIStorageConnection** _connection) {
 429   if (!aStorageKey.Equals(kMozStorageMemoryStorageKey)) {
 430     return NS_ERROR_INVALID_ARG;
 431   }
 432
 433   const bool interruptible =
 434       aConnectionFlags & mozIStorageService::CONNECTION_INTERRUPTIBLE;
 435
 436   int flags = SQLITE_OPEN_READWRITE;
 437
 438   if (!aName.IsEmpty()) {
 439     flags |= SQLITE_OPEN_URI;
 440   }
 441
 442   RefPtr<Connection> msc =
 443       new Connection(this, flags, Connection::SYNCHRONOUS, interruptible);
 444
 445   const nsresult rv = msc->initialize(aStorageKey, aName);
 446   NS_ENSURE_SUCCESS(rv, rv);
 447
 448   msc.forget(_connection);
 449   return NS_OK;
 450 }
 451
 452 namespace {
 453
 454 class AsyncInitDatabase final : public Runnable {
 455  public:
 456   AsyncInitDatabase(Connection* aConnection, nsIFile* aStorageFile,
 457                     int32_t aGrowthIncrement,
 458                     mozIStorageCompletionCallback* aCallback)
 459       : Runnable("storage::AsyncInitDatabase"),
 460         mConnection(aConnection),
 461         mStorageFile(aStorageFile),
 462         mGrowthIncrement(aGrowthIncrement),
 463         mCallback(aCallback) {
 464     MOZ_ASSERT(NS_IsMainThread());
 465   }
 466
 467   NS_IMETHOD Run() override {
 468     MOZ_ASSERT(!NS_IsMainThread());
 469     nsresult rv = mConnection->initializeOnAsyncThread(mStorageFile);
 470     if (NS_FAILED(rv)) {
 471       return DispatchResult(rv, nullptr);
 472     }
 473
 474     if (mGrowthIncrement >= 0) {
 475       // Ignore errors. In the future, we might wish to log them.
 476       (void)mConnection->SetGrowthIncrement(mGrowthIncrement, ""_ns);
 477     }
 478
 479     return DispatchResult(
 480         NS_OK, NS_ISUPPORTS_CAST(mozIStorageAsyncConnection*, mConnection));
 481   }
 482
 483  private:
 484   nsresult DispatchResult(nsresult aStatus, nsISupports* aValue) {
 485     RefPtr<CallbackComplete> event =
 486         new CallbackComplete(aStatus, aValue, mCallback.forget());
 487     return NS_DispatchToMainThread(event);
 488   }
 489
 490   ~AsyncInitDatabase() {
 491     NS_ReleaseOnMainThread("AsyncInitDatabase::mStorageFile",
 492                            mStorageFile.forget());
 493     NS_ReleaseOnMainThread("AsyncInitDatabase::mConnection",
 494                            mConnection.forget());
 495
 496     // Generally, the callback will be released by CallbackComplete.
 497     // However, if for some reason Run() is not executed, we still
 498     // need to ensure that it is released here.
 499     NS_ReleaseOnMainThread("AsyncInitDatabase::mCallback", mCallback.forget());
 500   }
 501
 502   RefPtr<Connection> mConnection;
 503   nsCOMPtr<nsIFile> mStorageFile;
 504   int32_t mGrowthIncrement;
 505   RefPtr<mozIStorageCompletionCallback> mCallback;
 506 };
 507
 508 }  // namespace
 509
 510 NS_IMETHODIMP
 511 Service::OpenAsyncDatabase(nsIVariant* aDatabaseStore, uint32_t aOpenFlags,
 512                            uint32_t /* aConnectionFlags */,
 513                            mozIStorageCompletionCallback* aCallback) {
 514   if (!NS_IsMainThread()) {
 515     return NS_ERROR_NOT_SAME_THREAD;
 516   }
 517   NS_ENSURE_ARG(aDatabaseStore);
 518   NS_ENSURE_ARG(aCallback);
 519
 520   const bool shared = aOpenFlags & mozIStorageService::OPEN_SHARED;
 521   const bool ignoreLockingMode =
 522       aOpenFlags & mozIStorageService::OPEN_IGNORE_LOCKING_MODE;
 523   // Specifying ignoreLockingMode will force use of the readOnly flag:
 524   const bool readOnly =
 525       ignoreLockingMode || (aOpenFlags & mozIStorageService::OPEN_READONLY);
 526   int flags = readOnly ? SQLITE_OPEN_READONLY : SQLITE_OPEN_READWRITE;
 527
 528   nsCOMPtr<nsIFile> storageFile;
 529   nsCOMPtr<nsISupports> dbStore;
 530   nsresult rv = aDatabaseStore->GetAsISupports(getter_AddRefs(dbStore));
 531   if (NS_SUCCEEDED(rv)) {
 532     // Generally, aDatabaseStore holds the database nsIFile.
 533     storageFile = do_QueryInterface(dbStore, &rv);
 534     if (NS_FAILED(rv)) {
 535       return NS_ERROR_INVALID_ARG;
 536     }
 537
 538     nsCOMPtr<nsIFile> cloned;
 539     rv = storageFile->Clone(getter_AddRefs(cloned));
 540     MOZ_ASSERT(NS_SUCCEEDED(rv));
 541     storageFile = std::move(cloned);
 542
 543     if (!readOnly) {
 544       // Ensure that SQLITE_OPEN_CREATE is passed in for compatibility reasons.
 545       flags |= SQLITE_OPEN_CREATE;
 546     }
 547
 548     // Apply the shared-cache option.
 549     flags |= shared ? SQLITE_OPEN_SHAREDCACHE : SQLITE_OPEN_PRIVATECACHE;
 550   } else {
 551     // Sometimes, however, it's a special database name.
 552     nsAutoCString keyString;
 553     rv = aDatabaseStore->GetAsACString(keyString);
 554     if (NS_FAILED(rv) || !keyString.Equals(kMozStorageMemoryStorageKey)) {
 555       return NS_ERROR_INVALID_ARG;
 556     }
 557
 558     // Just fall through with nullptr storageFile, this will cause the storage
 559     // connection to use a memory DB.
 560   }
 561
 562   // Create connection on this thread, but initialize it on its helper thread.
 563   RefPtr<Connection> msc =
 564       new Connection(this, flags, Connection::ASYNCHRONOUS,
 565                      /* interruptible */ true, ignoreLockingMode);
 566   nsCOMPtr<nsIEventTarget> target = msc->getAsyncExecutionTarget();
 567   MOZ_ASSERT(target,
 568              "Cannot initialize a connection that has been closed already");
 569
 570   RefPtr<AsyncInitDatabase> asyncInit = new AsyncInitDatabase(
 571       msc, storageFile, /* growthIncrement */ -1, aCallback);
 572   return target->Dispatch(asyncInit, nsIEventTarget::DISPATCH_NORMAL);
 573 }
 574
 575 NS_IMETHODIMP
 576 Service::OpenDatabase(nsIFile* aDatabaseFile, uint32_t aConnectionFlags,
 577                       mozIStorageConnection** _connection) {
 578   NS_ENSURE_ARG(aDatabaseFile);
 579
 580   const bool interruptible =
 581       aConnectionFlags & mozIStorageService::CONNECTION_INTERRUPTIBLE;
 582
 583   // Always ensure that SQLITE_OPEN_CREATE is passed in for compatibility
 584   // reasons.
 585   const int flags =
 586       SQLITE_OPEN_READWRITE | SQLITE_OPEN_SHAREDCACHE | SQLITE_OPEN_CREATE;
 587   RefPtr<Connection> msc =
 588       new Connection(this, flags, Connection::SYNCHRONOUS, interruptible);
 589
 590   const nsresult rv = msc->initialize(aDatabaseFile);
 591   NS_ENSURE_SUCCESS(rv, rv);
 592
 593   msc.forget(_connection);
 594   return NS_OK;
 595 }
 596
 597 NS_IMETHODIMP
 598 Service::OpenUnsharedDatabase(nsIFile* aDatabaseFile, uint32_t aConnectionFlags,
 599                               mozIStorageConnection** _connection) {
 600   NS_ENSURE_ARG(aDatabaseFile);
 601
 602   const bool interruptible =
 603       aConnectionFlags & mozIStorageService::CONNECTION_INTERRUPTIBLE;
 604
 605   // Always ensure that SQLITE_OPEN_CREATE is passed in for compatibility
 606   // reasons.
 607   const int flags =
 608       SQLITE_OPEN_READWRITE | SQLITE_OPEN_PRIVATECACHE | SQLITE_OPEN_CREATE;
 609   RefPtr<Connection> msc =
 610       new Connection(this, flags, Connection::SYNCHRONOUS, interruptible);
 611
 612   const nsresult rv = msc->initialize(aDatabaseFile);
 613   NS_ENSURE_SUCCESS(rv, rv);
 614
 615   msc.forget(_connection);
 616   return NS_OK;
 617 }
 618
 619 NS_IMETHODIMP
 620 Service::OpenDatabaseWithFileURL(nsIFileURL* aFileURL,
 621                                  const nsACString& aTelemetryFilename,
 622                                  uint32_t aConnectionFlags,
 623                                  mozIStorageConnection** _connection) {
 624   NS_ENSURE_ARG(aFileURL);
 625
 626   const bool interruptible =
 627       aConnectionFlags & mozIStorageService::CONNECTION_INTERRUPTIBLE;
 628
 629   // Always ensure that SQLITE_OPEN_CREATE is passed in for compatibility
 630   // reasons.
 631   const int flags = SQLITE_OPEN_READWRITE | SQLITE_OPEN_SHAREDCACHE |
 632                     SQLITE_OPEN_CREATE | SQLITE_OPEN_URI;
 633   RefPtr<Connection> msc =
 634       new Connection(this, flags, Connection::SYNCHRONOUS, interruptible);
 635
 636   const nsresult rv = msc->initialize(aFileURL, aTelemetryFilename);
 637   NS_ENSURE_SUCCESS(rv, rv);
 638
 639   msc.forget(_connection);
 640   return NS_OK;
 641 }
 642
 643 NS_IMETHODIMP
 644 Service::BackupDatabaseFile(nsIFile* aDBFile, const nsAString& aBackupFileName,
 645                             nsIFile* aBackupParentDirectory, nsIFile** backup) {
 646   nsresult rv;
 647   nsCOMPtr<nsIFile> parentDir = aBackupParentDirectory;
 648   if (!parentDir) {
 649     // This argument is optional, and defaults to the same parent directory
 650     // as the current file.
 651     rv = aDBFile->GetParent(getter_AddRefs(parentDir));
 652     NS_ENSURE_SUCCESS(rv, rv);
 653   }
 654
 655   nsCOMPtr<nsIFile> backupDB;
 656   rv = parentDir->Clone(getter_AddRefs(backupDB));
 657   NS_ENSURE_SUCCESS(rv, rv);
 658
 659   rv = backupDB->Append(aBackupFileName);
 660   NS_ENSURE_SUCCESS(rv, rv);
 661
 662   rv = backupDB->CreateUnique(nsIFile::NORMAL_FILE_TYPE, 0600);
 663   NS_ENSURE_SUCCESS(rv, rv);
 664
 665   nsAutoString fileName;
 666   rv = backupDB->GetLeafName(fileName);
 667   NS_ENSURE_SUCCESS(rv, rv);
 668
 669   rv = backupDB->Remove(false);
 670   NS_ENSURE_SUCCESS(rv, rv);
 671
 672   backupDB.forget(backup);
 673
 674   return aDBFile->CopyTo(parentDir, fileName);
 675 }
 676
 677 ////////////////////////////////////////////////////////////////////////////////
 678 //// nsIObserver
 679
 680 NS_IMETHODIMP
 681 Service::Observe(nsISupports*, const char* aTopic, const char16_t*) {
 682   if (strcmp(aTopic, "memory-pressure") == 0) {
 683     minimizeMemory();
 684   } else if (strcmp(aTopic, "xpcom-shutdown-threads") == 0) {
 685     // The Service is kept alive by our strong observer references and
 686     // references held by Connection instances.  Since we're about to remove the
 687     // former and then wait for the latter ones to go away, it behooves us to
 688     // hold a strong reference to ourselves so our calls to getConnections() do
 689     // not happen on a deleted object.
 690     RefPtr<Service> kungFuDeathGrip = this;
 691
 692     nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
 693
 694     for (size_t i = 0; i < ArrayLength(sObserverTopics); ++i) {
 695       (void)os->RemoveObserver(this, sObserverTopics[i]);
 696     }
 697
 698     SpinEventLoopUntil("storage::Service::Observe(xpcom-shutdown-threads)"_ns,
 699                        [&]() -> bool {
 700                          // We must wait until all the closing connections are
 701                          // closed.
 702                          nsTArray<RefPtr<Connection>> connections;
 703                          getConnections(connections);
 704                          for (auto& conn : connections) {
 705                            if (conn->isClosing()) {
 706                              return false;
 707                            }
 708                          }
 709                          return true;
 710                        });
 711
 712 #ifdef DEBUG
 713     nsTArray<RefPtr<Connection>> connections;
 714     getConnections(connections);
 715     for (uint32_t i = 0, n = connections.Length(); i < n; i++) {
 716       if (!connections[i]->isClosed()) {
 717         // getFilename is only the leaf name for the database file,
 718         // so it shouldn't contain privacy-sensitive information.
 719         CrashReporter::AnnotateCrashReport(
 720             CrashReporter::Annotation::StorageConnectionNotClosed,
 721             connections[i]->getFilename());
 722         printf_stderr("Storage connection not closed: %s",
 723                       connections[i]->getFilename().get());
 724         MOZ_CRASH();
 725       }
 726     }
 727 #endif
 728   }
 729
 730   return NS_OK;
 731 }
 732
 733 }  // namespace storage
 734 }  // namespace mozilla