dxva: add support for new dxva2 and d3d11 hwaccel APIs
[ffmpeg.git] / libavutil / threadmessage.c
1 /*
2  * Copyright (c) 2014 Nicolas George
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public License
8  * as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public License
17  * along with FFmpeg; if not, write to the Free Software Foundation, Inc.,
18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20
21 #include "fifo.h"
22 #include "threadmessage.h"
23 #include "thread.h"
24
25 struct AVThreadMessageQueue {
26 #if HAVE_THREADS
27     AVFifoBuffer *fifo;
28     pthread_mutex_t lock;
29     pthread_cond_t cond_recv;
30     pthread_cond_t cond_send;
31     int err_send;
32     int err_recv;
33     unsigned elsize;
34     void (*free_func)(void *msg);
35 #else
36     int dummy;
37 #endif
38 };
39
40 int av_thread_message_queue_alloc(AVThreadMessageQueue **mq,
41                                   unsigned nelem,
42                                   unsigned elsize)
43 {
44 #if HAVE_THREADS
45     AVThreadMessageQueue *rmq;
46     int ret = 0;
47
48     if (nelem > INT_MAX / elsize)
49         return AVERROR(EINVAL);
50     if (!(rmq = av_mallocz(sizeof(*rmq))))
51         return AVERROR(ENOMEM);
52     if ((ret = pthread_mutex_init(&rmq->lock, NULL))) {
53         av_free(rmq);
54         return AVERROR(ret);
55     }
56     if ((ret = pthread_cond_init(&rmq->cond_recv, NULL))) {
57         pthread_mutex_destroy(&rmq->lock);
58         av_free(rmq);
59         return AVERROR(ret);
60     }
61     if ((ret = pthread_cond_init(&rmq->cond_send, NULL))) {
62         pthread_cond_destroy(&rmq->cond_recv);
63         pthread_mutex_destroy(&rmq->lock);
64         av_free(rmq);
65         return AVERROR(ret);
66     }
67     if (!(rmq->fifo = av_fifo_alloc(elsize * nelem))) {
68         pthread_cond_destroy(&rmq->cond_send);
69         pthread_cond_destroy(&rmq->cond_recv);
70         pthread_mutex_destroy(&rmq->lock);
71         av_free(rmq);
72         return AVERROR(ret);
73     }
74     rmq->elsize = elsize;
75     *mq = rmq;
76     return 0;
77 #else
78     *mq = NULL;
79     return AVERROR(ENOSYS);
80 #endif /* HAVE_THREADS */
81 }
82
83 void av_thread_message_queue_set_free_func(AVThreadMessageQueue *mq,
84                                            void (*free_func)(void *msg))
85 {
86 #if HAVE_THREADS
87     mq->free_func = free_func;
88 #endif
89 }
90
91 void av_thread_message_queue_free(AVThreadMessageQueue **mq)
92 {
93 #if HAVE_THREADS
94     if (*mq) {
95         av_thread_message_flush(*mq);
96         av_fifo_freep(&(*mq)->fifo);
97         pthread_cond_destroy(&(*mq)->cond_send);
98         pthread_cond_destroy(&(*mq)->cond_recv);
99         pthread_mutex_destroy(&(*mq)->lock);
100         av_freep(mq);
101     }
102 #endif
103 }
104
105 #if HAVE_THREADS
106
107 static int av_thread_message_queue_send_locked(AVThreadMessageQueue *mq,
108                                                void *msg,
109                                                unsigned flags)
110 {
111     while (!mq->err_send && av_fifo_space(mq->fifo) < mq->elsize) {
112         if ((flags & AV_THREAD_MESSAGE_NONBLOCK))
113             return AVERROR(EAGAIN);
114         pthread_cond_wait(&mq->cond_send, &mq->lock);
115     }
116     if (mq->err_send)
117         return mq->err_send;
118     av_fifo_generic_write(mq->fifo, msg, mq->elsize, NULL);
119     /* one message is sent, signal one receiver */
120     pthread_cond_signal(&mq->cond_recv);
121     return 0;
122 }
123
124 static int av_thread_message_queue_recv_locked(AVThreadMessageQueue *mq,
125                                                void *msg,
126                                                unsigned flags)
127 {
128     while (!mq->err_recv && av_fifo_size(mq->fifo) < mq->elsize) {
129         if ((flags & AV_THREAD_MESSAGE_NONBLOCK))
130             return AVERROR(EAGAIN);
131         pthread_cond_wait(&mq->cond_recv, &mq->lock);
132     }
133     if (av_fifo_size(mq->fifo) < mq->elsize)
134         return mq->err_recv;
135     av_fifo_generic_read(mq->fifo, msg, mq->elsize, NULL);
136     /* one message space appeared, signal one sender */
137     pthread_cond_signal(&mq->cond_send);
138     return 0;
139 }
140
141 #endif /* HAVE_THREADS */
142
143 int av_thread_message_queue_send(AVThreadMessageQueue *mq,
144                                  void *msg,
145                                  unsigned flags)
146 {
147 #if HAVE_THREADS
148     int ret;
149
150     pthread_mutex_lock(&mq->lock);
151     ret = av_thread_message_queue_send_locked(mq, msg, flags);
152     pthread_mutex_unlock(&mq->lock);
153     return ret;
154 #else
155     return AVERROR(ENOSYS);
156 #endif /* HAVE_THREADS */
157 }
158
159 int av_thread_message_queue_recv(AVThreadMessageQueue *mq,
160                                  void *msg,
161                                  unsigned flags)
162 {
163 #if HAVE_THREADS
164     int ret;
165
166     pthread_mutex_lock(&mq->lock);
167     ret = av_thread_message_queue_recv_locked(mq, msg, flags);
168     pthread_mutex_unlock(&mq->lock);
169     return ret;
170 #else
171     return AVERROR(ENOSYS);
172 #endif /* HAVE_THREADS */
173 }
174
175 void av_thread_message_queue_set_err_send(AVThreadMessageQueue *mq,
176                                           int err)
177 {
178 #if HAVE_THREADS
179     pthread_mutex_lock(&mq->lock);
180     mq->err_send = err;
181     pthread_cond_broadcast(&mq->cond_send);
182     pthread_mutex_unlock(&mq->lock);
183 #endif /* HAVE_THREADS */
184 }
185
186 void av_thread_message_queue_set_err_recv(AVThreadMessageQueue *mq,
187                                           int err)
188 {
189 #if HAVE_THREADS
190     pthread_mutex_lock(&mq->lock);
191     mq->err_recv = err;
192     pthread_cond_broadcast(&mq->cond_recv);
193     pthread_mutex_unlock(&mq->lock);
194 #endif /* HAVE_THREADS */
195 }
196
197 #if HAVE_THREADS
198 static void free_func_wrap(void *arg, void *msg, int size)
199 {
200     AVThreadMessageQueue *mq = arg;
201     mq->free_func(msg);
202 }
203 #endif
204
205 void av_thread_message_flush(AVThreadMessageQueue *mq)
206 {
207 #if HAVE_THREADS
208     int used, off;
209     void *free_func = mq->free_func;
210
211     pthread_mutex_lock(&mq->lock);
212     used = av_fifo_size(mq->fifo);
213     if (free_func)
214         for (off = 0; off < used; off += mq->elsize)
215             av_fifo_generic_peek_at(mq->fifo, mq, off, mq->elsize, free_func_wrap);
216     av_fifo_drain(mq->fifo, used);
217     /* only the senders need to be notified since the queue is empty and there
218      * is nothing to read */
219     pthread_cond_broadcast(&mq->cond_send);
220     pthread_mutex_unlock(&mq->lock);
221 #endif /* HAVE_THREADS */
222 }