0,0 → 1,471 |
/* |
SDL - Simple DirectMedia Layer |
Copyright (C) 1997, 1998, 1999, 2000, 2001 Sam Lantinga |
|
This library is free software; you can redistribute it and/or |
modify it under the terms of the GNU Library General Public |
License as published by the Free Software Foundation; either |
version 2 of the License, or (at your option) any later version. |
|
This library is distributed in the hope that it will be useful, |
but WITHOUT ANY WARRANTY; without even the implied warranty of |
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
Library General Public License for more details. |
|
You should have received a copy of the GNU Library General Public |
License along with this library; if not, write to the Free |
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
|
Sam Lantinga |
slouken@devolution.com |
*/ |
|
|
/* General event handling code for SDL */ |
|
#include <stdio.h> |
#include <string.h> |
|
#include "SDL.h" |
#include "SDL_thread.h" |
#include "SDL_mutex.h" |
#include "SDL_events.h" |
#include "SDL_events_c.h" |
#include "SDL_timer_c.h" |
#ifndef DISABLE_JOYSTICK |
#include "SDL_joystick_c.h" |
#endif |
#ifndef ENABLE_X11 |
#define DISABLE_X11 |
#endif |
#include "SDL_syswm.h" |
#include "SDL_sysevents.h" |
|
/* Public data -- the event filter */ |
SDL_EventFilter SDL_EventOK = NULL; |
Uint8 SDL_ProcessEvents[SDL_NUMEVENTS]; |
static Uint32 SDL_eventstate = 0; |
|
/* Private data -- event queue */ |
#define MAXEVENTS 128 |
static struct { |
SDL_mutex *lock; |
int active; |
int head; |
int tail; |
SDL_Event event[MAXEVENTS]; |
int wmmsg_next; |
struct SDL_SysWMmsg wmmsg[MAXEVENTS]; |
} SDL_EventQ; |
|
/* Private data -- event locking structure */ |
static struct { |
SDL_mutex *lock; |
int safe; |
} SDL_EventLock; |
|
/* Thread functions */ |
static SDL_Thread *SDL_EventThread = NULL; /* Thread handle */ |
static Uint32 event_thread; /* The event thread id */ |
|
void SDL_Lock_EventThread(void) |
{ |
if ( SDL_EventThread && (SDL_ThreadID() != event_thread) ) { |
/* Grab lock and spin until we're sure event thread stopped */ |
SDL_mutexP(SDL_EventLock.lock); |
while ( ! SDL_EventLock.safe ) { |
SDL_Delay(1); |
} |
} |
} |
void SDL_Unlock_EventThread(void) |
{ |
if ( SDL_EventThread && (SDL_ThreadID() != event_thread) ) { |
SDL_mutexV(SDL_EventLock.lock); |
} |
} |
|
static int SDL_GobbleEvents(void *unused) |
{ |
SDL_SetTimerThreaded(2); |
event_thread = SDL_ThreadID(); |
while ( SDL_EventQ.active ) { |
SDL_VideoDevice *video = current_video; |
SDL_VideoDevice *this = current_video; |
|
/* Get events from the video subsystem */ |
if ( video ) { |
video->PumpEvents(this); |
} |
|
/* Queue pending key-repeat events */ |
SDL_CheckKeyRepeat(); |
|
#ifndef DISABLE_JOYSTICK |
/* Check for joystick state change */ |
if ( SDL_numjoysticks && (SDL_eventstate & SDL_JOYEVENTMASK) ) { |
SDL_JoystickUpdate(); |
} |
#endif |
|
/* Give up the CPU for the rest of our timeslice */ |
SDL_EventLock.safe = 1; |
if( SDL_timer_running ) { |
SDL_ThreadedTimerCheck(); |
} |
SDL_Delay(1); |
|
/* Check for event locking. |
On the P of the lock mutex, if the lock is held, this thread |
will wait until the lock is released before continuing. The |
safe flag will be set, meaning that the other thread can go |
about it's business. The safe flag is reset before the V, |
so as soon as the mutex is free, other threads can see that |
it's not safe to interfere with the event thread. |
*/ |
SDL_mutexP(SDL_EventLock.lock); |
SDL_EventLock.safe = 0; |
SDL_mutexV(SDL_EventLock.lock); |
} |
SDL_SetTimerThreaded(0); |
event_thread = 0; |
return(0); |
} |
|
static int SDL_StartEventThread(Uint32 flags) |
{ |
/* Reset everything to zero */ |
SDL_EventThread = NULL; |
memset(&SDL_EventLock, 0, sizeof(SDL_EventLock)); |
|
/* Create the lock and set ourselves active */ |
#ifndef DISABLE_THREADS |
SDL_EventQ.lock = SDL_CreateMutex(); |
if ( SDL_EventQ.lock == NULL ) { |
#ifdef macintosh /* On MacOS 7/8, you can't multithread, so no lock needed */ |
; |
#else |
return(-1); |
#endif |
} |
#endif /* !DISABLE_THREADS */ |
SDL_EventQ.active = 1; |
|
if ( (flags&SDL_INIT_EVENTTHREAD) == SDL_INIT_EVENTTHREAD ) { |
SDL_EventLock.lock = SDL_CreateMutex(); |
if ( SDL_EventLock.lock == NULL ) { |
return(-1); |
} |
SDL_EventLock.safe = 0; |
|
SDL_EventThread = SDL_CreateThread(SDL_GobbleEvents, NULL); |
if ( SDL_EventThread == NULL ) { |
return(-1); |
} |
} else { |
event_thread = 0; |
} |
return(0); |
} |
|
static void SDL_StopEventThread(void) |
{ |
SDL_EventQ.active = 0; |
if ( SDL_EventThread ) { |
SDL_WaitThread(SDL_EventThread, NULL); |
SDL_EventThread = NULL; |
SDL_DestroyMutex(SDL_EventLock.lock); |
} |
SDL_DestroyMutex(SDL_EventQ.lock); |
} |
|
Uint32 SDL_EventThreadID(void) |
{ |
return(event_thread); |
} |
|
/* Public functions */ |
|
void SDL_StopEventLoop(void) |
{ |
/* Halt the event thread, if running */ |
SDL_StopEventThread(); |
|
/* Clean out EventQ */ |
SDL_EventQ.head = 0; |
SDL_EventQ.tail = 0; |
SDL_EventQ.wmmsg_next = 0; |
} |
|
/* This function (and associated calls) may be called more than once */ |
int SDL_StartEventLoop(Uint32 flags) |
{ |
int retcode; |
|
/* Clean out the event queue */ |
SDL_EventThread = NULL; |
SDL_EventQ.lock = NULL; |
SDL_StopEventLoop(); |
|
/* No filter to start with, process most event types */ |
SDL_EventOK = NULL; |
memset(SDL_ProcessEvents,SDL_ENABLE,sizeof(SDL_ProcessEvents)); |
SDL_eventstate = ~0; |
/* It's not save to call SDL_EventState() yet */ |
SDL_eventstate &= ~(0x00000001 << SDL_SYSWMEVENT); |
SDL_ProcessEvents[SDL_SYSWMEVENT] = SDL_IGNORE; |
|
/* Initialize event handlers */ |
retcode = 0; |
retcode += SDL_AppActiveInit(); |
retcode += SDL_KeyboardInit(); |
retcode += SDL_MouseInit(); |
retcode += SDL_QuitInit(); |
if ( retcode < 0 ) { |
/* We don't expect them to fail, but... */ |
return(-1); |
} |
|
/* Create the lock and event thread */ |
if ( SDL_StartEventThread(flags) < 0 ) { |
SDL_StopEventLoop(); |
return(-1); |
} |
return(0); |
} |
|
|
/* Add an event to the event queue -- called with the queue locked */ |
static int SDL_AddEvent(SDL_Event *event) |
{ |
int tail, added; |
|
tail = (SDL_EventQ.tail+1)%MAXEVENTS; |
if ( tail == SDL_EventQ.head ) { |
/* Overflow, drop event */ |
added = 0; |
} else { |
SDL_EventQ.event[SDL_EventQ.tail] = *event; |
if (event->type == SDL_SYSWMEVENT) { |
/* Note that it's possible to lose an event */ |
int next = SDL_EventQ.wmmsg_next; |
SDL_EventQ.wmmsg[next] = *event->syswm.msg; |
SDL_EventQ.event[SDL_EventQ.tail].syswm.msg = |
&SDL_EventQ.wmmsg[next]; |
SDL_EventQ.wmmsg_next = (next+1)%MAXEVENTS; |
} |
SDL_EventQ.tail = tail; |
added = 1; |
} |
return(added); |
} |
|
/* Cut an event, and return the next valid spot, or the tail */ |
/* -- called with the queue locked */ |
static int SDL_CutEvent(int spot) |
{ |
if ( spot == SDL_EventQ.head ) { |
SDL_EventQ.head = (SDL_EventQ.head+1)%MAXEVENTS; |
return(SDL_EventQ.head); |
} else |
if ( (spot+1)%MAXEVENTS == SDL_EventQ.tail ) { |
SDL_EventQ.tail = spot; |
return(SDL_EventQ.tail); |
} else |
/* We cut the middle -- shift everything over */ |
{ |
int here, next; |
|
/* This can probably be optimized with memcpy() -- careful! */ |
if ( --SDL_EventQ.tail < 0 ) { |
SDL_EventQ.tail = MAXEVENTS-1; |
} |
for ( here=spot; here != SDL_EventQ.tail; here = next ) { |
next = (here+1)%MAXEVENTS; |
SDL_EventQ.event[here] = SDL_EventQ.event[next]; |
} |
return(spot); |
} |
/* NOTREACHED */ |
} |
|
/* Lock the event queue, take a peep at it, and unlock it */ |
int SDL_PeepEvents(SDL_Event *events, int numevents, SDL_eventaction action, |
Uint32 mask) |
{ |
int i, used; |
|
/* Don't look after we've quit */ |
if ( ! SDL_EventQ.active ) { |
return(0); |
} |
/* Lock the event queue */ |
used = 0; |
if ( SDL_mutexP(SDL_EventQ.lock) == 0 ) { |
if ( action == SDL_ADDEVENT ) { |
for ( i=0; i<numevents; ++i ) { |
used += SDL_AddEvent(&events[i]); |
} |
} else { |
SDL_Event tmpevent; |
int spot; |
|
/* If 'events' is NULL, just see if they exist */ |
if ( events == NULL ) { |
action = SDL_PEEKEVENT; |
numevents = 1; |
events = &tmpevent; |
} |
spot = SDL_EventQ.head; |
while ((used < numevents)&&(spot != SDL_EventQ.tail)) { |
if ( mask & SDL_EVENTMASK(SDL_EventQ.event[spot].type) ) { |
events[used++] = SDL_EventQ.event[spot]; |
if ( action == SDL_GETEVENT ) { |
spot = SDL_CutEvent(spot); |
} else { |
spot = (spot+1)%MAXEVENTS; |
} |
} else { |
spot = (spot+1)%MAXEVENTS; |
} |
} |
} |
SDL_mutexV(SDL_EventQ.lock); |
} else { |
SDL_SetError("Couldn't lock event queue"); |
used = -1; |
} |
return(used); |
} |
|
/* Run the system dependent event loops */ |
void SDL_PumpEvents(void) |
{ |
if ( !SDL_EventThread ) { |
SDL_VideoDevice *video = current_video; |
SDL_VideoDevice *this = current_video; |
|
/* Get events from the video subsystem */ |
if ( video ) { |
video->PumpEvents(this); |
} |
|
/* Queue pending key-repeat events */ |
SDL_CheckKeyRepeat(); |
|
#ifndef DISABLE_JOYSTICK |
/* Check for joystick state change */ |
if ( SDL_numjoysticks && (SDL_eventstate & SDL_JOYEVENTMASK) ) { |
SDL_JoystickUpdate(); |
} |
#endif |
} |
} |
|
/* Public functions */ |
|
int SDL_PollEvent (SDL_Event *event) |
{ |
SDL_PumpEvents(); |
|
return(SDL_PeepEvents(event, 1, SDL_GETEVENT, SDL_ALLEVENTS)); |
} |
|
int SDL_WaitEvent (SDL_Event *event) |
{ |
while ( 1 ) { |
SDL_PumpEvents(); |
switch(SDL_PeepEvents(event, 1, SDL_GETEVENT, SDL_ALLEVENTS)) { |
case -1: return -1; |
case 1: return 1; |
case 0: SDL_Delay(10); |
} |
} |
} |
|
int SDL_PushEvent(SDL_Event *event) |
{ |
return(SDL_PeepEvents(event, 1, SDL_ADDEVENT, 0)); |
} |
|
void SDL_SetEventFilter (SDL_EventFilter filter) |
{ |
SDL_Event bitbucket; |
|
/* Set filter and discard pending events */ |
SDL_EventOK = filter; |
while ( SDL_PollEvent(&bitbucket) > 0 ) |
; |
} |
|
SDL_EventFilter SDL_GetEventFilter(void) |
{ |
return(SDL_EventOK); |
} |
|
Uint8 SDL_EventState (Uint8 type, int state) |
{ |
SDL_Event bitbucket; |
Uint8 current_state; |
|
/* If SDL_ALLEVENTS was specified... */ |
if ( type == 0xFF ) { |
current_state = SDL_IGNORE; |
for ( type=0; type<SDL_NUMEVENTS; ++type ) { |
if ( SDL_ProcessEvents[type] != SDL_IGNORE ) { |
current_state = SDL_ENABLE; |
} |
SDL_ProcessEvents[type] = state; |
if ( state == SDL_ENABLE ) { |
SDL_eventstate |= (0x00000001 << (type)); |
} else { |
SDL_eventstate &= ~(0x00000001 << (type)); |
} |
} |
while ( SDL_PollEvent(&bitbucket) > 0 ) |
; |
return(current_state); |
} |
|
/* Just set the state for one event type */ |
current_state = SDL_ProcessEvents[type]; |
switch (state) { |
case SDL_IGNORE: |
case SDL_ENABLE: |
/* Set state and discard pending events */ |
SDL_ProcessEvents[type] = state; |
if ( state == SDL_ENABLE ) { |
SDL_eventstate |= (0x00000001 << (type)); |
} else { |
SDL_eventstate &= ~(0x00000001 << (type)); |
} |
while ( SDL_PollEvent(&bitbucket) > 0 ) |
; |
break; |
default: |
/* Querying state? */ |
break; |
} |
return(current_state); |
} |
|
/* This is a generic event handler. |
*/ |
int SDL_PrivateSysWMEvent(SDL_SysWMmsg *message) |
{ |
int posted; |
|
posted = 0; |
if ( SDL_ProcessEvents[SDL_SYSWMEVENT] == SDL_ENABLE ) { |
SDL_Event event; |
memset(&event, 0, sizeof(event)); |
event.type = SDL_SYSWMEVENT; |
event.syswm.msg = message; |
if ( (SDL_EventOK == NULL) || (*SDL_EventOK)(&event) ) { |
posted = 1; |
SDL_PushEvent(&event); |
} |
} |
/* Update internal event state */ |
return(posted); |
} |