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/*
* Copyright (c) 2004 Michael Niedermayer <michaelni@gmx.at>
*
* This library 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 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <semaphore.h>
#include <pthread.h>
//#define DEBUG
#include "avcodec.h"
#include "common.h"
typedef struct ThreadContext{
AVCodecContext *avctx;
pthread_t thread;
sem_t work_sem;
sem_t done_sem;
int (*func)(AVCodecContext *c, void *arg);
void *arg;
int ret;
}ThreadContext;
static void * thread_func(void *v){
ThreadContext *c= v;
for(;;){
//printf("thread_func %X enter wait\n", (int)v); fflush(stdout);
sem_wait(&c->work_sem);
//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 NULL;
//printf("thread_func %X signal complete\n", (int)v); fflush(stdout);
sem_post(&c->done_sem);
}
return NULL;
}
/**
* free what has been allocated by avcodec_thread_init().
* must be called after decoding has finished, especially dont 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++){
int val;
sem_getvalue(&c[i].work_sem, &val); assert(val == 0);
sem_getvalue(&c[i].done_sem, &val); assert(val == 0);
c[i].func= NULL;
sem_post(&c[i].work_sem);
pthread_join(c[i].thread, NULL);
sem_destroy(&c[i].work_sem);
sem_destroy(&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, val;
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++){
sem_getvalue(&c[i].work_sem, &val); assert(val == 0);
sem_getvalue(&c[i].done_sem, &val); assert(val == 0);
c[i].arg= arg[i];
c[i].func= func;
c[i].ret= 12345;
sem_post(&c[i].work_sem);
}
for(i=0; i<count; i++){
sem_wait(&c[i].done_sem);
sem_getvalue(&c[i].work_sem, &val); assert(val == 0);
sem_getvalue(&c[i].done_sem, &val); assert(val == 0);
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;
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(sem_init(&c[i].work_sem, 0, 0))
goto fail;
if(sem_init(&c[i].done_sem, 0, 0))
goto fail;
//printf("create thread %d\n", i); fflush(stdout);
if(pthread_create(&c[i].thread, NULL, thread_func, &c[i]))
goto fail;
}
//printf("init done\n"); fflush(stdout);
s->execute= avcodec_thread_execute;
return 0;
fail:
avcodec_thread_free(s);
return -1;
}
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