| 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 | #if HAVE_THREADS |
| 24 | #if HAVE_PTHREADS |
| 25 | #include <pthread.h> |
| 26 | #elif HAVE_W32THREADS |
| 27 | #include "compat/w32pthreads.h" |
| 28 | #elif HAVE_OS2THREADS |
| 29 | #include "compat/os2threads.h" |
| 30 | #else |
| 31 | #error "Unknown threads implementation" |
| 32 | #endif |
| 33 | #endif |
| 34 | |
| 35 | struct AVThreadMessageQueue { |
| 36 | #if HAVE_THREADS |
| 37 | AVFifoBuffer *fifo; |
| 38 | pthread_mutex_t lock; |
| 39 | pthread_cond_t cond; |
| 40 | int err_send; |
| 41 | int err_recv; |
| 42 | unsigned elsize; |
| 43 | #else |
| 44 | int dummy; |
| 45 | #endif |
| 46 | }; |
| 47 | |
| 48 | int av_thread_message_queue_alloc(AVThreadMessageQueue **mq, |
| 49 | unsigned nelem, |
| 50 | unsigned elsize) |
| 51 | { |
| 52 | #if HAVE_THREADS |
| 53 | AVThreadMessageQueue *rmq; |
| 54 | int ret = 0; |
| 55 | |
| 56 | if (nelem > INT_MAX / elsize) |
| 57 | return AVERROR(EINVAL); |
| 58 | if (!(rmq = av_mallocz(sizeof(*rmq)))) |
| 59 | return AVERROR(ENOMEM); |
| 60 | if ((ret = pthread_mutex_init(&rmq->lock, NULL))) { |
| 61 | av_free(rmq); |
| 62 | return AVERROR(ret); |
| 63 | } |
| 64 | if ((ret = pthread_cond_init(&rmq->cond, NULL))) { |
| 65 | pthread_mutex_destroy(&rmq->lock); |
| 66 | av_free(rmq); |
| 67 | return AVERROR(ret); |
| 68 | } |
| 69 | if (!(rmq->fifo = av_fifo_alloc(elsize * nelem))) { |
| 70 | pthread_cond_destroy(&rmq->cond); |
| 71 | pthread_mutex_destroy(&rmq->lock); |
| 72 | av_free(rmq); |
| 73 | return AVERROR(ret); |
| 74 | } |
| 75 | rmq->elsize = elsize; |
| 76 | *mq = rmq; |
| 77 | return 0; |
| 78 | #else |
| 79 | *mq = NULL; |
| 80 | return AVERROR(ENOSYS); |
| 81 | #endif /* HAVE_THREADS */ |
| 82 | } |
| 83 | |
| 84 | void av_thread_message_queue_free(AVThreadMessageQueue **mq) |
| 85 | { |
| 86 | #if HAVE_THREADS |
| 87 | if (*mq) { |
| 88 | av_fifo_freep(&(*mq)->fifo); |
| 89 | pthread_cond_destroy(&(*mq)->cond); |
| 90 | pthread_mutex_destroy(&(*mq)->lock); |
| 91 | av_freep(mq); |
| 92 | } |
| 93 | #endif |
| 94 | } |
| 95 | |
| 96 | #if HAVE_THREADS |
| 97 | |
| 98 | static int av_thread_message_queue_send_locked(AVThreadMessageQueue *mq, |
| 99 | void *msg, |
| 100 | unsigned flags) |
| 101 | { |
| 102 | while (!mq->err_send && av_fifo_space(mq->fifo) < mq->elsize) { |
| 103 | if ((flags & AV_THREAD_MESSAGE_NONBLOCK)) |
| 104 | return AVERROR(EAGAIN); |
| 105 | pthread_cond_wait(&mq->cond, &mq->lock); |
| 106 | } |
| 107 | if (mq->err_send) |
| 108 | return mq->err_send; |
| 109 | av_fifo_generic_write(mq->fifo, msg, mq->elsize, NULL); |
| 110 | pthread_cond_signal(&mq->cond); |
| 111 | return 0; |
| 112 | } |
| 113 | |
| 114 | static int av_thread_message_queue_recv_locked(AVThreadMessageQueue *mq, |
| 115 | void *msg, |
| 116 | unsigned flags) |
| 117 | { |
| 118 | while (!mq->err_recv && av_fifo_size(mq->fifo) < mq->elsize) { |
| 119 | if ((flags & AV_THREAD_MESSAGE_NONBLOCK)) |
| 120 | return AVERROR(EAGAIN); |
| 121 | pthread_cond_wait(&mq->cond, &mq->lock); |
| 122 | } |
| 123 | if (av_fifo_size(mq->fifo) < mq->elsize) |
| 124 | return mq->err_recv; |
| 125 | av_fifo_generic_read(mq->fifo, msg, mq->elsize, NULL); |
| 126 | pthread_cond_signal(&mq->cond); |
| 127 | return 0; |
| 128 | } |
| 129 | |
| 130 | #endif /* HAVE_THREADS */ |
| 131 | |
| 132 | int av_thread_message_queue_send(AVThreadMessageQueue *mq, |
| 133 | void *msg, |
| 134 | unsigned flags) |
| 135 | { |
| 136 | #if HAVE_THREADS |
| 137 | int ret; |
| 138 | |
| 139 | pthread_mutex_lock(&mq->lock); |
| 140 | ret = av_thread_message_queue_send_locked(mq, msg, flags); |
| 141 | pthread_mutex_unlock(&mq->lock); |
| 142 | return ret; |
| 143 | #else |
| 144 | return AVERROR(ENOSYS); |
| 145 | #endif /* HAVE_THREADS */ |
| 146 | } |
| 147 | |
| 148 | int av_thread_message_queue_recv(AVThreadMessageQueue *mq, |
| 149 | void *msg, |
| 150 | unsigned flags) |
| 151 | { |
| 152 | #if HAVE_THREADS |
| 153 | int ret; |
| 154 | |
| 155 | pthread_mutex_lock(&mq->lock); |
| 156 | ret = av_thread_message_queue_recv_locked(mq, msg, flags); |
| 157 | pthread_mutex_unlock(&mq->lock); |
| 158 | return ret; |
| 159 | #else |
| 160 | return AVERROR(ENOSYS); |
| 161 | #endif /* HAVE_THREADS */ |
| 162 | } |
| 163 | |
| 164 | void av_thread_message_queue_set_err_send(AVThreadMessageQueue *mq, |
| 165 | int err) |
| 166 | { |
| 167 | #if HAVE_THREADS |
| 168 | pthread_mutex_lock(&mq->lock); |
| 169 | mq->err_send = err; |
| 170 | pthread_cond_broadcast(&mq->cond); |
| 171 | pthread_mutex_unlock(&mq->lock); |
| 172 | #endif /* HAVE_THREADS */ |
| 173 | } |
| 174 | |
| 175 | void av_thread_message_queue_set_err_recv(AVThreadMessageQueue *mq, |
| 176 | int err) |
| 177 | { |
| 178 | #if HAVE_THREADS |
| 179 | pthread_mutex_lock(&mq->lock); |
| 180 | mq->err_recv = err; |
| 181 | pthread_cond_broadcast(&mq->cond); |
| 182 | pthread_mutex_unlock(&mq->lock); |
| 183 | #endif /* HAVE_THREADS */ |
| 184 | } |