Source code

Revision control

Other Tools

/* -*- 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;
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 already_AddRefed<Service> getSingleton();
NS_DECL_THREADSAFE_ISUPPORTS
NS_DECL_MOZISTORAGESERVICE
NS_DECL_NSIOBSERVER
NS_DECL_NSIMEMORYREPORTER
/**
* 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;
}
static const int32_t kDefaultPageSize = 32768;
/**
* 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;
struct AutoVFSRegistration {
int Init(UniquePtr<sqlite3_vfs> aVFS);
~AutoVFSRegistration();
private:
UniquePtr<sqlite3_vfs> mVFS;
};
// The order of these members should match the order of Init calls in
// initialize(), to ensure that the unregistration takes place in the reverse
// order.
AutoVFSRegistration mTelemetrySqliteVFS;
AutoVFSRegistration mTelemetryExclSqliteVFS;
AutoVFSRegistration mObfuscatingSqliteVFS;
/**
* 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();
/**
* 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;
};
} // namespace storage
} // namespace mozilla
#endif /* MOZSTORAGESERVICE_H */