gecko-dev/xpcom/components/nsIServiceManager.h

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 4 -*-
*
* The contents of this file are subject to the Netscape Public
* License Version 1.1 (the "License"); you may not use this file
* except in compliance with the License. You may obtain a copy of
* the License at http://www.mozilla.org/NPL/
*
* Software distributed under the License is distributed on an "AS
* IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
* implied. See the License for the specific language governing
* rights and limitations under the License.
*
* The Original Code is mozilla.org code.
*
* The Initial Developer of the Original Code is Netscape
* Communications Corporation. Portions created by Netscape are
* Copyright (C) 1998 Netscape Communications Corporation. All
* Rights Reserved.
*
* Contributor(s):
* Pierre Phaneuf <pp@ludusdesign.com>
*/
#ifndef nsIServiceManager_h___
#define nsIServiceManager_h___
#include "nsIComponentManager.h"
#include "nsID.h"
#ifndef nsCOMPtr_h___
#include "nsCOMPtr.h"
#endif
class nsIShutdownListener;
#define NS_ISERVICEMANAGER_IID \
{ /* cf0df3b0-3401-11d2-8163-006008119d7a */ \
0xcf0df3b0, \
0x3401, \
0x11d2, \
{0x81, 0x63, 0x00, 0x60, 0x08, 0x11, 0x9d, 0x7a} \
}
/**
* The nsIServiceManager manager interface provides a means to obtain
* global services in an application. The service manager depends on the
* repository to find and instantiate factories to obtain services.
*
* Users of the service manager must first obtain a pointer to the global
* service manager by calling NS_GetGlobalServiceManager. After that,
* they can request specific services by calling GetService. When they are
* finished they can NS_RELEASE() the service as usual.
*
* nsICacheManager* cm;
* nsServiceManager::GetService(kCacheManagerCID, kICacheManagerIID, (nsISupports**)&cm);
*
* ... use cm, and then sometime later ...
*
* NS_RELEASE(cm);
*
* A user of a service may keep references to particular services indefinitely
* and only must call Release when it shuts down.
*
* Shutdown Listeners: However if the user
* wishes to voluntarily cooperate with the shutdown of the service it is
* using, it may supply an nsIShutdownListener to provide for asynchronous
* release of the services it is using. The shutdown listener's OnShutdown
* method will be called for a service that is being shut down, and it is
* its responsiblity to release references obtained from that service if at
* all possible.
*
* The process of shutting down a particular service is initiated by calling
* the service manager's ShutdownService method. This will iterate through
* all the registered shutdown listeners for the service being shut down, and
* then will attempt to unload the library associated with the service if
* possible. The status result of ShutdownService indicates whether the
* service was successfully shut down, failed, or was not in service.
*
* XXX QUESTIONS:
* - Should a "service" be more than nsISupports? Should it be a factory
* and/or have Startup(), Shutdown(), etc.
* - If the asynchronous OnShutdown operation gets called, does the user
* of a service still need to call ReleaseService? (Or should they _not_
* call it?)
*/
class nsIServiceManager : public nsISupports {
public:
NS_DEFINE_STATIC_IID_ACCESSOR(NS_ISERVICEMANAGER_IID);
/**
* RegisterService may be called explicitly to register a service
* with the service manager. If a service is not registered explicitly,
* the component manager will be used to create an instance according
* to the class ID specified.
*/
NS_IMETHOD
RegisterService(const nsCID& aClass, nsISupports* aService) = 0;
/**
* Requests a service to be shut down, possibly unloading its DLL.
*
* @returns NS_OK - if shutdown was successful and service was unloaded,
* @returns NS_ERROR_SERVICE_NOT_FOUND - if shutdown failed because
* the service was not currently loaded
* @returns NS_ERROR_SERVICE_IN_USE - if shutdown failed because some
* user of the service wouldn't voluntarily release it by using
* a shutdown listener.
*/
NS_IMETHOD
UnregisterService(const nsCID& aClass) = 0;
NS_IMETHOD
GetService(const nsCID& aClass, const nsIID& aIID,
nsISupports* *result,
nsIShutdownListener* shutdownListener = nsnull) = 0;
/* OBSOLETE: use NS_RELEASE(service) instead. */
NS_IMETHOD
ReleaseService(const nsCID& aClass, nsISupports* service,
nsIShutdownListener* shutdownListener = nsnull) = 0;
////////////////////////////////////////////////////////////////////////////
// let's do it again, this time with ContractIDs...
NS_IMETHOD
RegisterService(const char* aContractID, nsISupports* aService) = 0;
NS_IMETHOD
UnregisterService(const char* aContractID) = 0;
NS_IMETHOD
GetService(const char* aContractID, const nsIID& aIID,
nsISupports* *result,
nsIShutdownListener* shutdownListener = nsnull) = 0;
/* OBSOLETE */
NS_IMETHOD
ReleaseService(const char* aContractID, nsISupports* service,
nsIShutdownListener* shutdownListener = nsnull) = 0;
};
#define NS_ERROR_SERVICE_NOT_FOUND NS_ERROR_GENERATE_SUCCESS(NS_ERROR_MODULE_XPCOM, 22)
#define NS_ERROR_SERVICE_IN_USE NS_ERROR_GENERATE_SUCCESS(NS_ERROR_MODULE_XPCOM, 23)
////////////////////////////////////////////////////////////////////////////////
#define NS_ISHUTDOWNLISTENER_IID \
{ /* 56decae0-3406-11d2-8163-006008119d7a */ \
0x56decae0, \
0x3406, \
0x11d2, \
{0x81, 0x63, 0x00, 0x60, 0x08, 0x11, 0x9d, 0x7a} \
}
class nsIShutdownListener : public nsISupports {
public:
NS_DEFINE_STATIC_IID_ACCESSOR(NS_ISHUTDOWNLISTENER_IID);
NS_IMETHOD
OnShutdown(const nsCID& aClass, nsISupports* service) = 0;
};
////////////////////////////////////////////////////////////////////////////////
// Interface to Global Services
class NS_COM nsServiceManager {
public:
static nsresult
RegisterService(const nsCID& aClass, nsISupports* aService);
static nsresult
UnregisterService(const nsCID& aClass);
static nsresult
GetService(const nsCID& aClass, const nsIID& aIID,
nsISupports* *result,
nsIShutdownListener* shutdownListener = nsnull);
/* OBSOLETE: use NS_RELEASE(service) instead. */
static nsresult
ReleaseService(const nsCID& aClass, nsISupports* service,
nsIShutdownListener* shutdownListener = nsnull);
////////////////////////////////////////////////////////////////////////////
// let's do it again, this time with ContractIDs...
static nsresult
RegisterService(const char* aContractID, nsISupports* aService);
static nsresult
UnregisterService(const char* aContractID);
static nsresult
GetService(const char* aContractID, const nsIID& aIID,
nsISupports* *result,
nsIShutdownListener* shutdownListener = nsnull);
/* OBSOLETE: use NS_RELEASE(service) instead. */
static nsresult
ReleaseService(const char* aContractID, nsISupports* service,
nsIShutdownListener* shutdownListener = nsnull);
////////////////////////////////////////////////////////////////////////////
static nsresult GetGlobalServiceManager(nsIServiceManager* *result);
// This method can be called when shutting down the application. It
// releases all the global services, and deletes the global service manager.
static nsresult ShutdownGlobalServiceManager(nsIServiceManager* *result);
};
////////////////////////////////////////////////////////////////////////////
// Using servicemanager with COMPtrs
class NS_COM nsGetServiceByCID : public nsCOMPtr_helper
{
public:
nsGetServiceByCID( const nsCID& aCID, nsISupports* aServiceManager, nsresult* aErrorPtr )
: mCID(aCID),
mServiceManager( do_QueryInterface(aServiceManager) ),
mErrorPtr(aErrorPtr)
{
// nothing else to do
}
virtual nsresult operator()( const nsIID&, void** ) const;
virtual ~nsGetServiceByCID() {};
private:
const nsCID& mCID;
nsCOMPtr<nsIServiceManager> mServiceManager;
nsresult* mErrorPtr;
};
inline
const nsGetServiceByCID
do_GetService( const nsCID& aCID, nsresult* error = 0 )
{
return nsGetServiceByCID(aCID, 0, error);
}
inline
const nsGetServiceByCID
do_GetService( const nsCID& aCID, nsISupports* aServiceManager, nsresult* error = 0 )
{
return nsGetServiceByCID(aCID, aServiceManager, error);
}
class NS_COM nsGetServiceByContractID : public nsCOMPtr_helper
{
public:
nsGetServiceByContractID( const char* aContractID, nsISupports* aServiceManager, nsresult* aErrorPtr )
: mContractID(aContractID),
mServiceManager( do_QueryInterface(aServiceManager) ),
mErrorPtr(aErrorPtr)
{
// nothing else to do
}
virtual nsresult operator()( const nsIID&, void** ) const;
virtual ~nsGetServiceByContractID() {};
private:
const char* mContractID;
nsCOMPtr<nsIServiceManager> mServiceManager;
nsresult* mErrorPtr;
};
inline
const nsGetServiceByContractID
do_GetService( const char* aContractID, nsresult* error = 0 )
{
return nsGetServiceByContractID(aContractID, 0, error);
}
inline
const nsGetServiceByContractID
do_GetService( const char* aContractID, nsISupports* aServiceManager, nsresult* error = 0 )
{
return nsGetServiceByContractID(aContractID, aServiceManager, error);
}
class NS_COM nsGetServiceFromCategory : public nsCOMPtr_helper
{
public:
nsGetServiceFromCategory(const char* aCategory, const char* aEntry,
nsISupports* aServiceManager,
nsresult* aErrorPtr)
: mCategory(aCategory),
mEntry(aEntry),
mServiceManager( do_QueryInterface(aServiceManager) ),
mErrorPtr(aErrorPtr)
{
// nothing else to do
}
virtual nsresult operator()( const nsIID&, void** ) const;
virtual ~nsGetServiceFromCategory() {};
protected:
const char* mCategory;
const char* mEntry;
nsCOMPtr<nsIServiceManager> mServiceManager;
nsresult* mErrorPtr;
};
inline
const nsGetServiceFromCategory
do_GetServiceFromCategory( const char* category, const char* entry,
nsresult* error = 0)
{
return nsGetServiceFromCategory(category, entry, 0, error);
}
////////////////////////////////////////////////////////////////////////////////
// NS_WITH_SERVICE: macro to make using services easier.
//
// Services can be used with COMPtrs. GetService() is used to get a service.
// NS_RELEASE() can be called on the service got to release it.
//
// NOTE: ReleaseService() is OBSOLETE.
//
// Now you can replace this:
// {
// nsIMyService* service;
// rv = nsServiceManager::GetService(kMyServiceCID, NS_GET_IID(nsIMyService),
// &service);
// if (NS_FAILED(rv)) return rv;
// service->Doit(...); // use my service
// rv = nsServiceManager::ReleaseService(kMyServiceCID, service);
// }
// with this:
// {
// NS_WITH_SERVICE(nsIMyService, service, kMyServiceCID, &rv);
// if (NS_FAILED(rv)) return rv;
// service->Doit(...); // use my service
// }
// and the automatic destructor from COMPtr will take care of releasing the service.
////////////////////////////////////////////////////////////////////////////////
#define NS_WITH_SERVICE(T, var, cid, rvAddr) \
nsCOMPtr<T> var = do_GetService(cid, rvAddr);
#define NS_WITH_SERVICE1(T, var, isupportsServMgr, cid, rvAddr) \
nsCOMPtr<T> var = do_GetService(cid, isupportsServMgr, rvAddr);
////////////////////////////////////////////////////////////////////////////////
// NS_NewServiceManager: For when you want to create a service manager
// in a given context.
extern NS_COM nsresult
NS_NewServiceManager(nsIServiceManager* *result);
////////////////////////////////////////////////////////////////////////////////
// Initialization of XPCOM. Creates the global ComponentManager, ServiceManager
// and registers xpcom components with the ComponentManager. Should be called
// before any call can be made to XPCOM. Currently we are coping with this
// not being called and internally initializing XPCOM if not already.
//
// binDirectory is the absolute path to the mozilla bin directory.
// directory must contain a "components" directory and a component.reg file.
extern NS_COM nsresult
NS_InitXPCOM(nsIServiceManager* *result, nsIFile* binDirectory);
extern NS_COM nsresult
NS_InitXPCOM2(const char* productName, nsIServiceManager* *result, nsIFile* binDirectory);
////////////////////////////////////////////////////////////////////////////////
// Shutdown of XPCOM. XPCOM hosts an observer (NS_XPCOM_SHUTDOWN_OBSERVER_ID)
// for modules to observer the shutdown. The first thing NS_ShutdownXPCOM()
// does is to notify observers of NS_XPCOM_SHUTDOWN_OBSERVER_ID. After the
// observers have been notified, access to ServiceManager will return
// NS_ERROR_UNEXPECTED.
//
extern NS_COM nsresult
NS_ShutdownXPCOM(nsIServiceManager* servMgr);
////////////////////////////////////////////////////////////////////////////////
// Observing xpcom shutdown
#define NS_XPCOM_SHUTDOWN_OBSERVER_ID "xpcom-shutdown"
#define NS_XPCOM_AUTOREGISTRATION_OBSERVER_ID "xpcom-autoregistration"
#endif /* nsIServiceManager_h___ */