aboutsummaryrefslogtreecommitdiffstats
path: root/libavcodec/w32thread.c
blob: 48ccf5e0b781c7b52a6e3906059eb68f8364114d (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
/*
 * 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
 *
 */
//#define DEBUG

#include "avcodec.h"
#include "common.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 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 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++){

        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;
}