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authorwtc%netscape.com <devnull@localhost>2000-01-26 19:40:47 +0000
committerwtc%netscape.com <devnull@localhost>2000-01-26 19:40:47 +0000
commiteba49325bfa99b5e313ef3d4a63860f50e4a3984 (patch)
treeb176e35498131d4987dcb5d60adb06aad3de56d7
parentf532380a652d0f9cab8f7390405cbc1f856f605a (diff)
downloadnspr-hg-PLEVENT_MOVE_BRANCH.tar.gz
Removed plevent.h from PLEVENT_MOVE_BRANCH. (Bugzilla bug #17101)PLEVENT_MOVE_BRANCH
-rw-r--r--lib/ds/plevent.h497
1 files changed, 0 insertions, 497 deletions
diff --git a/lib/ds/plevent.h b/lib/ds/plevent.h
deleted file mode 100644
index 38871055..00000000
--- a/lib/ds/plevent.h
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@@ -1,497 +0,0 @@
-/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
-/*
- * The contents of this file are subject to the Netscape Public License
- * Version 1.1 (the "NPL"); you may not use this file except in
- * compliance with the NPL. You may obtain a copy of the NPL at
- * http://www.mozilla.org/NPL/
- *
- * Software distributed under the NPL is distributed on an "AS IS" basis,
- * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
- * for the specific language governing rights and limitations under the
- * NPL.
- *
- * The Initial Developer of this code under the NPL is Netscape
- * Communications Corporation. Portions created by Netscape are
- * Copyright (C) 1998 Netscape Communications Corporation. All Rights
- * Reserved.
- */
-
-/**********************************************************************
-NSPL Events
-
-Defining Events
----------------
-
-Events are essentially structures that represent argument lists for a
-function that will run on another thread. All event structures you
-define must include a PLEvent struct as their first field:
-
- typedef struct MyEventType {
- PLEvent e;
- // arguments follow...
- int x;
- char* y;
- } MyEventType;
-
-It is also essential that you establish a model of ownership for each
-argument passed in an event record, i.e. whether particular arguments
-will be deleted by the event destruction callback, or whether they
-only loaned to the event handler callback, and guaranteed to persist
-until the time at which the handler is called.
-
-Sending Events
---------------
-
-Events are initialized by PL_InitEvent and can be sent via
-PL_PostEvent or PL_PostSynchronousEvent. Events can also have an
-owner. The owner of an event can revoke all the events in a given
-event-queue by calling PL_RevokeEvents. An owner might want
-to do this if, for instance, it is being destroyed, and handling the
-events after the owner's destruction would cause an error (e.g. an
-MWContext).
-
-Since the act of initializing and posting an event must be coordinated
-with it's possible revocation, it is essential that the event-queue's
-monitor be entered surrounding the code that constructs, initializes
-and posts the event:
-
- void postMyEvent(MyOwner* owner, int x, char* y)
- {
- MyEventType* event;
-
- PL_ENTER_EVENT_QUEUE_MONITOR(myQueue);
-
- // construct
- event = PR_NEW(MyEventType);
- if (event == NULL) goto done;
-
- // initialize
- PL_InitEvent(event, owner,
- (PLHandleEventProc)handleMyEvent,
- (PLDestroyEventProc)destroyMyEvent);
- event->x = x;
- event->y = strdup(y);
-
- // post
- PL_PostEvent(myQueue, &event->e);
-
- done:
- PL_EXIT_EVENT_QUEUE_MONITOR(myQueue);
- }
-
-If you don't call PL_InitEvent and PL_PostEvent within the
-event-queue's monitor, you'll get a big red assert.
-
-Handling Events
----------------
-
-To handle an event you must write a callback that is passed the event
-record you defined containing the event's arguments:
-
- void* handleMyEvent(MyEventType* event)
- {
- doit(event->x, event->y);
- return NULL; // you could return a value for a sync event
- }
-
-Similarly for the destruction callback:
-
- void destroyMyEvent(MyEventType* event)
- {
- free(event->y); // created by strdup
- free(event);
- }
-
-Processing Events in Your Event Loop
-------------------------------------
-
-If your main loop only processes events delivered to the event queue,
-things are rather simple. You just get the next event (which may
-block), and then handle it:
-
- while (1) {
- event = PL_GetEvent(myQueue);
- PL_HandleEvent(event);
- }
-
-However, if other things must be waited on, you'll need to obtain a
-file-descriptor that represents your event queue, and hand it to select:
-
- fd = PL_GetEventQueueSelectFD(myQueue);
- ...add fd to select set...
- while (select(...)) {
- if (...fd...) {
- PL_ProcessPendingEvents(myQueue);
- }
- ...
- }
-
-Of course, with Motif and Windows it's more complicated than that, and
-on Mac it's completely different, but you get the picture.
-
-Revoking Events
----------------
-If at any time an owner of events is about to be destroyed, you must
-take steps to ensure that no one tries to use the event queue after
-the owner is gone (or a crash may result). You can do this by either
-processing all the events in the queue before destroying the owner:
-
- {
- ...
- PL_ENTER_EVENT_QUEUE_MONITOR(myQueue);
- PL_ProcessPendingEvents(myQueue);
- DestroyMyOwner(owner);
- PL_EXIT_EVENT_QUEUE_MONITOR(myQueue);
- ...
- }
-
-or by revoking the events that are in the queue for that owner. This
-removes them from the queue and calls their destruction callback:
-
- {
- ...
- PL_ENTER_EVENT_QUEUE_MONITOR(myQueue);
- PL_RevokeEvents(myQueue, owner);
- DestroyMyOwner(owner);
- PL_EXIT_EVENT_QUEUE_MONITOR(myQueue);
- ...
- }
-
-In either case it is essential that you be in the event-queue's monitor
-to ensure that all events are removed from the queue for that owner,
-and to ensure that no more events will be delivered for that owner.
-**********************************************************************/
-
-#ifndef prevent_h___
-#define prevent_h___
-
-#include "prtypes.h"
-#include "prclist.h"
-#include "prthread.h"
-#include "prmon.h"
-
-/* For HWND */
-#if defined(_WIN32) && !defined(__MINGW32__)
-#include <windef.h>
-#elif defined(WIN16) || defined(__MINGW32__)
-#include <windows.h>
-#elif defined(XP_OS2)
-#define INCL_DOSPROCESS
-#include <os2.h>
-#endif
-
-PR_BEGIN_EXTERN_C
-
-/* Typedefs */
-
-typedef struct PLEvent PLEvent;
-typedef struct PLEventQueue PLEventQueue;
-
-/*******************************************************************************
- * Event Queue Operations
- ******************************************************************************/
-
-/*
-** Creates a new event queue. Returns NULL on failure.
-*/
-PR_EXTERN(PLEventQueue*)
-PL_CreateEventQueue(char* name, PRThread* handlerThread);
-
-
-/* -----------------------------------------------------------------------
-** FUNCTION: PL_CreateNativeEventQueue()
-**
-** DESCRIPTION:
-** PL_CreateNativeEventQueue() creates an event queue that
-** uses platform specific notify mechanisms.
-**
-** For Unix, the platform specific notify mechanism provides
-** an FD that may be extracted using the function
-** PL_GetEventQueueSelectFD(). The FD returned may be used in
-** a select() function call.
-**
-** For Windows, the platform specific notify mechanism
-** provides an event receiver window that is called by
-** Windows to process the event using the windows message
-** pump engine.
-**
-** INPUTS:
-** name: A name, as a diagnostic aid.
-**
-** handlerThread: A pointer to the PRThread structure for
-** the thread that will "handle" events posted to this event
-** queue.
-**
-** RETURNS:
-** A pointer to a PLEventQueue structure or NULL.
-**
-*/
-PR_EXTERN(PLEventQueue *)
- PL_CreateNativeEventQueue(
- char *name,
- PRThread *handlerThread
- );
-
-/* -----------------------------------------------------------------------
-** FUNCTION: PL_CreateMonitoredEventQueue()
-**
-** DESCRIPTION:
-** PL_CreateMonitoredEventQueue() creates an event queue. No
-** platform specific notify mechanism is created with the
-** event queue.
-**
-** Users of this type of event queue must explicitly poll the
-** event queue to retreive and process events.
-**
-**
-** INPUTS:
-** name: A name, as a diagnostic aid.
-**
-** handlerThread: A pointer to the PRThread structure for
-** the thread that will "handle" events posted to this event
-** queue.
-**
-** RETURNS:
-** A pointer to a PLEventQueue structure or NULL.
-**
-*/
-PR_EXTERN(PLEventQueue *)
- PL_CreateMonitoredEventQueue(
- char *name,
- PRThread *handlerThread
- );
-
-/*
-** Destroys an event queue.
-*/
-PR_EXTERN(void)
-PL_DestroyEventQueue(PLEventQueue* self);
-
-/*
-** Returns the monitor associated with an event queue. This monitor is
-** selectable. The monitor should be entered to protect against anyone
-** calling PL_RevokeEvents while the event is trying to be constructed
-** and delivered.
-*/
-PR_EXTERN(PRMonitor*)
-PL_GetEventQueueMonitor(PLEventQueue* self);
-
-#define PL_ENTER_EVENT_QUEUE_MONITOR(queue) \
- PR_EnterMonitor(PL_GetEventQueueMonitor(queue))
-
-#define PL_EXIT_EVENT_QUEUE_MONITOR(queue) \
- PR_ExitMonitor(PL_GetEventQueueMonitor(queue))
-
-/*
-** Posts an event to an event queue, waking up any threads waiting for an
-** event. If event is NULL, notification still occurs, but no event will
-** be available.
-**
-** Any events delivered by this routine will be destroyed by PL_HandleEvent
-** when it is called (by the event-handling thread).
-*/
-PR_EXTERN(PRStatus)
-PL_PostEvent(PLEventQueue* self, PLEvent* event);
-
-/*
-** Like PL_PostEvent, this routine posts an event to the event handling
-** thread, but does so synchronously, waiting for the result. The result
-** which is the value of the handler routine is returned.
-**
-** Any events delivered by this routine will be not be destroyed by
-** PL_HandleEvent, but instead will be destroyed just before the result is
-** returned (by the current thread).
-*/
-PR_EXTERN(void*)
-PL_PostSynchronousEvent(PLEventQueue* self, PLEvent* event);
-
-/*
-** Gets an event from an event queue. Returns NULL if no event is
-** available.
-*/
-PR_EXTERN(PLEvent*)
-PL_GetEvent(PLEventQueue* self);
-
-/*
-** Returns true if there is an event available for PL_GetEvent.
-*/
-PR_EXTERN(PRBool)
-PL_EventAvailable(PLEventQueue* self);
-
-/*
-** This is the type of the function that must be passed to PL_MapEvents
-** (see description below).
-*/
-typedef void
-(PR_CALLBACK *PLEventFunProc)(PLEvent* event, void* data, PLEventQueue* queue);
-
-/*
-** Applies a function to every event in the event queue. This can be used
-** to selectively handle, filter, or remove events. The data pointer is
-** passed to each invocation of the function fun.
-*/
-PR_EXTERN(void)
-PL_MapEvents(PLEventQueue* self, PLEventFunProc fun, void* data);
-
-/*
-** This routine walks an event queue and destroys any event whose owner is
-** the owner specified. The == operation is used to compare owners.
-*/
-PR_EXTERN(void)
-PL_RevokeEvents(PLEventQueue* self, void* owner);
-
-/*
-** This routine processes all pending events in the event queue. It can be
-** called from the thread's main event-processing loop whenever the event
-** queue's selectFD is ready (returned by PL_GetEventQueueSelectFD).
-*/
-PR_EXTERN(void)
-PL_ProcessPendingEvents(PLEventQueue* self);
-
-/*******************************************************************************
- * Pure Event Queues
- *
- * For when you're only processing PLEvents and there is no native
- * select, thread messages, or AppleEvents.
- ******************************************************************************/
-
-/*
-** Blocks until an event can be returned from the event queue. This routine
-** may return NULL if the current thread is interrupted.
-*/
-PR_EXTERN(PLEvent*)
-PL_WaitForEvent(PLEventQueue* self);
-
-/*
-** One stop shopping if all you're going to do is process PLEvents. Just
-** call this and it loops forever processing events as they arrive. It will
-** terminate when your thread is interrupted or dies.
-*/
-PR_EXTERN(void)
-PL_EventLoop(PLEventQueue* self);
-
-/*******************************************************************************
- * Native Event Queues
- *
- * For when you need to call select, or WaitNextEvent, and yet also want
- * to handle PLEvents.
- ******************************************************************************/
-
-/*
-** This routine allows you to grab the file descriptor associated with an
-** event queue and use it in the readFD set of select. Useful for platforms
-** that support select, and must wait on other things besides just PLEvents.
-*/
-PR_EXTERN(PRInt32)
-PL_GetEventQueueSelectFD(PLEventQueue* self);
-
-/*
-** This routine will allow you to check to see if the given eventQueue in
-** on the current thread. It will return PR_TRUE if so, else it will return
-** PR_FALSE
-*/
-PR_EXTERN(PRBool)
- PL_IsQueueOnCurrentThread( PLEventQueue *queue );
-
-/*******************************************************************************
- * Event Operations
- ******************************************************************************/
-
-/*
-** The type of an event handler function. This function is passed as an
-** initialization argument to PL_InitEvent, and called by
-** PL_HandleEvent. If the event is called synchronously, a void* result
-** may be returned (otherwise any result will be ignored).
-*/
-typedef void*
-(PR_CALLBACK *PLHandleEventProc)(PLEvent* self);
-
-/*
-** The type of an event destructor function. This function is passed as
-** an initialization argument to PL_InitEvent, and called by
-** PL_DestroyEvent.
-*/
-typedef void
-(PR_CALLBACK *PLDestroyEventProc)(PLEvent* self);
-
-/*
-** Initializes an event. Usually events are embedded in a larger event
-** structure which holds event-specific data, so this is an initializer
-** for that embedded part of the structure.
-*/
-PR_EXTERN(void)
-PL_InitEvent(PLEvent* self, void* owner,
- PLHandleEventProc handler,
- PLDestroyEventProc destructor);
-
-/*
-** Returns the owner of an event.
-*/
-PR_EXTERN(void*)
-PL_GetEventOwner(PLEvent* self);
-
-/*
-** Handles an event, calling the event's handler routine.
-*/
-PR_EXTERN(void)
-PL_HandleEvent(PLEvent* self);
-
-/*
-** Destroys an event, calling the event's destructor.
-*/
-PR_EXTERN(void)
-PL_DestroyEvent(PLEvent* self);
-
-/*
-** Removes an event from an event queue.
-*/
-PR_EXTERN(void)
-PL_DequeueEvent(PLEvent* self, PLEventQueue* queue);
-
-/*******************************************************************************
- * Private Stuff
- ******************************************************************************/
-
-struct PLEvent {
- PRCList link;
- PLHandleEventProc handler;
- PLDestroyEventProc destructor;
- void* owner;
- void* synchronousResult;
- /* other fields follow... */
-};
-
-/******************************************************************************/
-
-/*
-** Returns the event queue associated with the main thread.
-**
-*/
-#ifdef XP_PC
-/* -----------------------------------------------------------------------
-** FUNCTION: PL_GetNativeEventReceiverWindow()
-**
-** DESCRIPTION:
-** PL_GetNativeEventReceiverWindow() returns the windows
-** handle of the event receiver window associated with the
-** referenced PLEventQueue argument.
-**
-** INPUTS:
-** PLEventQueue pointer
-**
-** RETURNS:
-** event receiver window handle.
-**
-** RESTRICTIONS: MS-Windows ONLY.
-**
-*/
-PR_EXTERN(HWND)
- PL_GetNativeEventReceiverWindow(
- PLEventQueue *eqp
- );
-
-#endif /* XP_PC */
-
-PR_END_EXTERN_C
-
-#endif /* prevent_h___ */