gecko-dev/xpcom/threads/nsEventQueueService.cpp

322 строки
7.6 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
*
* The contents of this file are subject to the Netscape Public License
* Version 1.0 (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 Communicator client 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.
*/
#include "prmon.h"
#include "nsIEventQueueService.h"
#include "nsHashtable.h"
#include "nsXPComFactory.h"
static NS_DEFINE_IID(kIEventQueueServiceIID, NS_IEVENTQUEUESERVICE_IID);
// XXX move to nsID.h or nsHashtable.h? (copied from nsRepository.cpp)
class ThreadKey: public nsHashKey {
private:
const PRThread* id;
public:
ThreadKey(const PRThread* aID) {
id = aID;
}
PRUint32 HashValue(void) const {
return (PRUint32)id;
}
PRBool Equals(const nsHashKey *aKey) const {
return (id == ((const ThreadKey *) aKey)->id);
}
nsHashKey *Clone(void) const {
return new ThreadKey(id);
}
};
/*
* This class maintains the data associated with each entry in the EventQueue
* service's hash table...
*
* It derives from nsISupports merely as a convienence since the entries are
* reference counted...
*/
class EventQueueEntry : public nsISupports
{
public:
EventQueueEntry();
~EventQueueEntry();
// nsISupports interface...
NS_DECL_ISUPPORTS
PLEventQueue* GetEventQueue(void);
private:
PLEventQueue* mEventQueue;
};
/* nsISupports interface implementation... */
NS_IMPL_ISUPPORTS(EventQueueEntry,kISupportsIID);
EventQueueEntry::EventQueueEntry()
{
NS_INIT_REFCNT();
#ifdef XP_PC
// XXX: For now only use the main eventQ... When the event queue is
// created via PL_CreateNativeEventQueue(...) this can go away...
PL_InitializeEventsLib("");
mEventQueue = PL_GetMainEventQueue();
#else
mEventQueue = PL_CreateEventQueue("Thread event queue...", PR_GetCurrentThread());
#endif
}
EventQueueEntry::~EventQueueEntry()
{
if (NULL != mEventQueue) {
PL_DestroyEventQueue(mEventQueue);
}
}
PLEventQueue* EventQueueEntry::GetEventQueue(void)
{
return mEventQueue;
}
class nsEventQueueServiceImpl : public nsIEventQueueService
{
public:
nsEventQueueServiceImpl();
// nsISupports interface...
NS_DECL_ISUPPORTS
// nsIEventQueueService interface...
NS_IMETHOD CreateThreadEventQueue(void);
NS_IMETHOD DestroyThreadEventQueue(void);
NS_IMETHOD GetThreadEventQueue(PRThread* aThread, PLEventQueue** aResult);
protected:
~nsEventQueueServiceImpl();
private:
nsHashtable* mEventQTable;
PRMonitor* mEventQMonitor;
};
nsEventQueueServiceImpl::nsEventQueueServiceImpl()
{
NS_INIT_REFCNT();
mEventQTable = new nsHashtable(16);
mEventQMonitor = PR_NewMonitor();
}
static PRBool
DeleteEntry(nsHashKey *aKey, void *aData, void* closure)
{
EventQueueEntry* evQueueEntry = (EventQueueEntry*)aData;
if (NULL != evQueueEntry) {
delete evQueueEntry;
}
return PR_TRUE;
}
nsEventQueueServiceImpl::~nsEventQueueServiceImpl()
{
// Destroy any remaining PLEventQueue's still in the hash table...
mEventQTable->Enumerate(DeleteEntry);
delete mEventQTable;
PR_DestroyMonitor(mEventQMonitor);
}
/* nsISupports interface implementation... */
NS_IMPL_ISUPPORTS(nsEventQueueServiceImpl,kIEventQueueServiceIID);
/* nsIEventQueueService interface implementation... */
NS_IMETHODIMP
nsEventQueueServiceImpl::CreateThreadEventQueue(void)
{
nsresult rv = NS_OK;
ThreadKey key(PR_GetCurrentThread());
EventQueueEntry* evQueueEntry;
/* Enter the lock which protects the EventQ hashtable... */
PR_EnterMonitor(mEventQMonitor);
/* Only create one event queue per thread... */
evQueueEntry = (EventQueueEntry*)mEventQTable->Get(&key);
if (NULL == evQueueEntry) {
evQueueEntry = new EventQueueEntry();
if (NULL == evQueueEntry) {
rv = NS_ERROR_OUT_OF_MEMORY;
goto done;
}
mEventQTable->Put(&key, evQueueEntry);
}
NS_ADDREF(evQueueEntry);
done:
// Release the EventQ lock...
PR_ExitMonitor(mEventQMonitor);
return rv;
}
NS_IMETHODIMP
nsEventQueueServiceImpl::DestroyThreadEventQueue(void)
{
nsresult rv = NS_OK;
ThreadKey key(PR_GetCurrentThread());
EventQueueEntry* evQueueEntry;
/* Enter the lock which protects the EventQ hashtable... */
PR_EnterMonitor(mEventQMonitor);
evQueueEntry = (EventQueueEntry*)mEventQTable->Get(&key);
if (NULL != evQueueEntry) {
nsrefcnt refcnt;
NS_RELEASE2(evQueueEntry, refcnt);
// Remove the entry from the hash table if this was the last reference...
if (0 == refcnt) {
mEventQTable->Remove(&key);
}
} else {
rv = NS_ERROR_FAILURE;
}
// Release the EventQ lock...
PR_ExitMonitor(mEventQMonitor);
return rv;
}
NS_IMETHODIMP
nsEventQueueServiceImpl::GetThreadEventQueue(PRThread* aThread, PLEventQueue** aResult)
{
nsresult rv = NS_OK;
EventQueueEntry* evQueueEntry;
ThreadKey key(aThread);
/* Enter the lock which protects the EventQ hashtable... */
PR_EnterMonitor(mEventQMonitor);
/* Parameter validation... */
if ((NULL == aThread) || (NULL == aResult)) {
rv = NS_ERROR_NULL_POINTER;
goto done;
}
evQueueEntry = (EventQueueEntry*)mEventQTable->Get(&key);
if (NULL != evQueueEntry) {
*aResult = evQueueEntry->GetEventQueue();
} else {
// XXX: Need error code for requesting an event queue when none exists...
rv = NS_ERROR_FAILURE;
goto done;
}
done:
// Release the EventQ lock...
PR_ExitMonitor(mEventQMonitor);
return rv;
}
//----------------------------------------------------------------------
static nsEventQueueServiceImpl* gServiceInstance = NULL;
class nsEventQueueServiceFactory : public nsFactory<nsEventQueueServiceImpl>
{
public:
NS_IMETHOD CreateInstance(nsISupports *aOuter,
const nsIID &aIID,
void **aResult);
};
NS_IMETHODIMP
nsEventQueueServiceFactory::CreateInstance(nsISupports *aOuter,
const nsIID &aIID,
void **aResult)
{
nsresult rv;
nsISupports* inst;
// Parameter validation...
if (NULL == aResult) {
rv = NS_ERROR_NULL_POINTER;
goto done;
}
// Do not support aggregatable components...
*aResult = NULL;
if (NULL != aOuter) {
rv = NS_ERROR_NO_AGGREGATION;
goto done;
}
if (NULL == gServiceInstance) {
// Create a new instance of the component...
NS_NEWXPCOM(gServiceInstance, nsEventQueueServiceImpl);
if (NULL == gServiceInstance) {
rv = NS_ERROR_OUT_OF_MEMORY;
goto done;
}
NS_ADDREF(gServiceInstance);
}
// If the QI fails, the component will be destroyed...
//
// Use a local copy so the NS_RELEASE() will not null the global
// pointer...
inst = gServiceInstance;
NS_ADDREF(inst);
rv = inst->QueryInterface(aIID, aResult);
NS_RELEASE(inst);
done:
return rv;
}
// Entry point to create nsEventQueueService factory instances...
nsresult NS_NewEventQueueServiceFactory(nsIFactory** aResult)
{
nsresult rv = NS_OK;
nsIFactory* inst = new nsEventQueueServiceFactory();
if (NULL == inst) {
rv = NS_ERROR_OUT_OF_MEMORY;
}
else {
NS_ADDREF(inst);
}
*aResult = inst;
return rv;
}