FFmpeg/libavcodec/w32thread.c
Ramiro Polla 5e4c7ca224 Add attribute that forces alignment of stack to functions that need it.
Necessary for systems that don't align by default to 16 bytes, required by some
SSE instructions.
Requires GCC >= 4.2.
Based on patch by Gaël Chardon.

Originally committed as revision 10106 to svn://svn.ffmpeg.org/ffmpeg/trunk
2007-08-13 15:28:29 +00:00

135 lines
3.8 KiB
C

/*
* Copyright (c) 2004 Michael Niedermayer <michaelni@gmx.at>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
//#define DEBUG
#include "avcodec.h"
#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#include <process.h>
typedef struct ThreadContext{
AVCodecContext *avctx;
HANDLE thread;
HANDLE work_sem;
HANDLE done_sem;
int (*func)(AVCodecContext *c, void *arg);
void *arg;
int ret;
}ThreadContext;
static unsigned __stdcall attribute_align_arg thread_func(void *v){
ThreadContext *c= v;
for(;;){
//printf("thread_func %X enter wait\n", (int)v); fflush(stdout);
WaitForSingleObject(c->work_sem, INFINITE);
//printf("thread_func %X after wait (func=%X)\n", (int)v, (int)c->func); fflush(stdout);
if(c->func)
c->ret= c->func(c->avctx, c->arg);
else
return 0;
//printf("thread_func %X signal complete\n", (int)v); fflush(stdout);
ReleaseSemaphore(c->done_sem, 1, 0);
}
return 0;
}
/**
* Free what has been allocated by avcodec_thread_init().
* Must be called after decoding has finished, especially do not call while avcodec_thread_execute() is running.
*/
void avcodec_thread_free(AVCodecContext *s){
ThreadContext *c= s->thread_opaque;
int i;
for(i=0; i<s->thread_count; i++){
c[i].func= NULL;
ReleaseSemaphore(c[i].work_sem, 1, 0);
WaitForSingleObject(c[i].thread, INFINITE);
if(c[i].work_sem) CloseHandle(c[i].work_sem);
if(c[i].done_sem) CloseHandle(c[i].done_sem);
}
av_freep(&s->thread_opaque);
}
int avcodec_thread_execute(AVCodecContext *s, int (*func)(AVCodecContext *c2, void *arg2),void **arg, int *ret, int count){
ThreadContext *c= s->thread_opaque;
int i;
assert(s == c->avctx);
assert(count <= s->thread_count);
/* note, we can be certain that this is not called with the same AVCodecContext by different threads at the same time */
for(i=0; i<count; i++){
c[i].arg= arg[i];
c[i].func= func;
c[i].ret= 12345;
ReleaseSemaphore(c[i].work_sem, 1, 0);
}
for(i=0; i<count; i++){
WaitForSingleObject(c[i].done_sem, INFINITE);
c[i].func= NULL;
if(ret) ret[i]= c[i].ret;
}
return 0;
}
int avcodec_thread_init(AVCodecContext *s, int thread_count){
int i;
ThreadContext *c;
uint32_t threadid;
s->thread_count= thread_count;
assert(!s->thread_opaque);
c= av_mallocz(sizeof(ThreadContext)*thread_count);
s->thread_opaque= c;
for(i=0; i<thread_count; i++){
//printf("init semaphors %d\n", i); fflush(stdout);
c[i].avctx= s;
if(!(c[i].work_sem = CreateSemaphore(NULL, 0, s->thread_count, NULL)))
goto fail;
if(!(c[i].done_sem = CreateSemaphore(NULL, 0, s->thread_count, NULL)))
goto fail;
//printf("create thread %d\n", i); fflush(stdout);
c[i].thread = (HANDLE)_beginthreadex(NULL, 0, thread_func, &c[i], 0, &threadid );
if( !c[i].thread ) goto fail;
}
//printf("init done\n"); fflush(stdout);
s->execute= avcodec_thread_execute;
return 0;
fail:
avcodec_thread_free(s);
return -1;
}