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Diffstat (limited to 'storage/mozStorageService.h')
| -rw-r--r-- | storage/mozStorageService.h | 197 |
1 files changed, 197 insertions, 0 deletions
diff --git a/storage/mozStorageService.h b/storage/mozStorageService.h new file mode 100644 index 000000000..effd330b1 --- /dev/null +++ b/storage/mozStorageService.h @@ -0,0 +1,197 @@ +/* -*- 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/. */ + +#ifndef MOZSTORAGESERVICE_H +#define MOZSTORAGESERVICE_H + +#include "nsCOMPtr.h" +#include "nsICollation.h" +#include "nsIFile.h" +#include "nsIMemoryReporter.h" +#include "nsIObserver.h" +#include "nsTArray.h" +#include "mozilla/Mutex.h" + +#include "mozIStorageService.h" + +class nsIMemoryReporter; +class nsIXPConnect; +struct sqlite3_vfs; + +namespace mozilla { +namespace storage { + +class Connection; +class Service : public mozIStorageService + , public nsIObserver + , public nsIMemoryReporter +{ +public: + /** + * Initializes the service. This must be called before any other function! + */ + nsresult initialize(); + + /** + * Compares two strings using the Service's locale-aware collation. + * + * @param aStr1 + * The string to be compared against aStr2. + * @param aStr2 + * The string to be compared against aStr1. + * @param aComparisonStrength + * The sorting strength, one of the nsICollation constants. + * @return aStr1 - aStr2. That is, if aStr1 < aStr2, returns a negative + * number. If aStr1 > aStr2, returns a positive number. If + * aStr1 == aStr2, returns 0. + */ + int localeCompareStrings(const nsAString &aStr1, + const nsAString &aStr2, + int32_t aComparisonStrength); + + static Service *getSingleton(); + + NS_DECL_THREADSAFE_ISUPPORTS + NS_DECL_MOZISTORAGESERVICE + NS_DECL_NSIOBSERVER + NS_DECL_NSIMEMORYREPORTER + + /** + * Obtains an already AddRefed pointer to XPConnect. This is used by + * language helpers. + */ + static already_AddRefed<nsIXPConnect> getXPConnect(); + + /** + * Obtains the cached data for the toolkit.storage.synchronous preference. + */ + static int32_t getSynchronousPref(); + + /** + * Obtains the default page size for this platform. The default value is + * specified in the SQLite makefile (SQLITE_DEFAULT_PAGE_SIZE) but it may be + * overriden with the PREF_TS_PAGESIZE hidden preference. + */ + static int32_t getDefaultPageSize() + { + return sDefaultPageSize; + } + + /** + * Returns a boolean value indicating whether or not the given page size is + * valid (currently understood as a power of 2 between 512 and 65536). + */ + static bool pageSizeIsValid(int32_t aPageSize) + { + return aPageSize == 512 || aPageSize == 1024 || aPageSize == 2048 || + aPageSize == 4096 || aPageSize == 8192 || aPageSize == 16384 || + aPageSize == 32768 || aPageSize == 65536; + } + + /** + * Registers the connection with the storage service. Connections are + * registered so they can be iterated over. + * + * @pre mRegistrationMutex is not held + * + * @param aConnection + * The connection to register. + */ + void registerConnection(Connection *aConnection); + + /** + * Unregisters the connection with the storage service. + * + * @pre mRegistrationMutex is not held + * + * @param aConnection + * The connection to unregister. + */ + void unregisterConnection(Connection *aConnection); + + /** + * Gets the list of open connections. Note that you must test each + * connection with mozIStorageConnection::connectionReady before doing + * anything with it, and skip it if it's not ready. + * + * @pre mRegistrationMutex is not held + * + * @param aConnections + * An inout param; it is cleared and the connections are appended to + * it. + * @return The open connections. + */ + void getConnections(nsTArray<RefPtr<Connection> >& aConnections); + +private: + Service(); + virtual ~Service(); + + /** + * Used for 1) locking around calls when initializing connections so that we + * can ensure that the state of sqlite3_enable_shared_cache is sane and 2) + * synchronizing access to mLocaleCollation. + */ + Mutex mMutex; + + sqlite3_vfs *mSqliteVFS; + + /** + * Protects mConnections. + */ + Mutex mRegistrationMutex; + + /** + * The list of connections we have created. Modifications to it are + * protected by |mRegistrationMutex|. + */ + nsTArray<RefPtr<Connection> > mConnections; + + /** + * Frees as much heap memory as possible from all of the known open + * connections. + */ + void minimizeMemory(); + + /** + * Shuts down the storage service, freeing all of the acquired resources. + */ + void shutdown(); + + /** + * Lazily creates and returns a collation created from the application's + * locale that all statements of all Connections of this Service may use. + * Since the collation's lifetime is that of the Service and no statement may + * execute outside the lifetime of the Service, this method returns a raw + * pointer. + */ + nsICollation *getLocaleCollation(); + + /** + * Lazily created collation that all statements of all Connections of this + * Service may use. The collation is created from the application's locale. + * + * @note Collation implementations are platform-dependent and in general not + * thread-safe. Access to this collation should be synchronized. + */ + nsCOMPtr<nsICollation> mLocaleCollation; + + nsCOMPtr<nsIFile> mProfileStorageFile; + + nsCOMPtr<nsIMemoryReporter> mStorageSQLiteReporter; + + static Service *gService; + + static nsIXPConnect *sXPConnect; + + static int32_t sSynchronousPref; + static int32_t sDefaultPageSize; +}; + +} // namespace storage +} // namespace mozilla + +#endif /* MOZSTORAGESERVICE_H */ |