diff options
Diffstat (limited to 'libavutil/threadmessage.c')
| -rw-r--r-- | libavutil/threadmessage.c | 184 |
1 files changed, 184 insertions, 0 deletions
diff --git a/libavutil/threadmessage.c b/libavutil/threadmessage.c new file mode 100644 index 0000000000..b7fcbe28c0 --- /dev/null +++ b/libavutil/threadmessage.c @@ -0,0 +1,184 @@ +/* + * Copyright (c) 2014 Nicolas George + * + * 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 + */ + +#include "fifo.h" +#include "threadmessage.h" +#if HAVE_THREADS +#if HAVE_PTHREADS +#include <pthread.h> +#elif HAVE_W32THREADS +#include "compat/w32pthreads.h" +#elif HAVE_OS2THREADS +#include "compat/os2threads.h" +#else +#error "Unknown threads implementation" +#endif +#endif + +struct AVThreadMessageQueue { +#if HAVE_THREADS + AVFifoBuffer *fifo; + pthread_mutex_t lock; + pthread_cond_t cond; + int err_send; + int err_recv; + unsigned elsize; +#else + int dummy; +#endif +}; + +int av_thread_message_queue_alloc(AVThreadMessageQueue **mq, + unsigned nelem, + unsigned elsize) +{ +#if HAVE_THREADS + AVThreadMessageQueue *rmq; + int ret = 0; + + if (nelem > INT_MAX / elsize) + return AVERROR(EINVAL); + if (!(rmq = av_mallocz(sizeof(*rmq)))) + return AVERROR(ENOMEM); + if ((ret = pthread_mutex_init(&rmq->lock, NULL))) { + av_free(rmq); + return AVERROR(ret); + } + if ((ret = pthread_cond_init(&rmq->cond, NULL))) { + pthread_mutex_destroy(&rmq->lock); + av_free(rmq); + return AVERROR(ret); + } + if (!(rmq->fifo = av_fifo_alloc(elsize * nelem))) { + pthread_cond_destroy(&rmq->cond); + pthread_mutex_destroy(&rmq->lock); + av_free(rmq); + return AVERROR(ret); + } + rmq->elsize = elsize; + *mq = rmq; + return 0; +#else + *mq = NULL; + return AVERROR(ENOSYS); +#endif /* HAVE_THREADS */ +} + +void av_thread_message_queue_free(AVThreadMessageQueue **mq) +{ +#if HAVE_THREADS + if (*mq) { + av_fifo_freep(&(*mq)->fifo); + pthread_cond_destroy(&(*mq)->cond); + pthread_mutex_destroy(&(*mq)->lock); + av_freep(mq); + } +#endif +} + +#if HAVE_THREADS + +static int av_thread_message_queue_send_locked(AVThreadMessageQueue *mq, + void *msg, + unsigned flags) +{ + while (!mq->err_send && av_fifo_space(mq->fifo) < mq->elsize) { + if ((flags & AV_THREAD_MESSAGE_NONBLOCK)) + return AVERROR(EAGAIN); + pthread_cond_wait(&mq->cond, &mq->lock); + } + if (mq->err_send) + return mq->err_send; + av_fifo_generic_write(mq->fifo, msg, mq->elsize, NULL); + pthread_cond_signal(&mq->cond); + return 0; +} + +static int av_thread_message_queue_recv_locked(AVThreadMessageQueue *mq, + void *msg, + unsigned flags) +{ + while (!mq->err_recv && av_fifo_size(mq->fifo) < mq->elsize) { + if ((flags & AV_THREAD_MESSAGE_NONBLOCK)) + return AVERROR(EAGAIN); + pthread_cond_wait(&mq->cond, &mq->lock); + } + if (av_fifo_size(mq->fifo) < mq->elsize) + return mq->err_recv; + av_fifo_generic_read(mq->fifo, msg, mq->elsize, NULL); + pthread_cond_signal(&mq->cond); + return 0; +} + +#endif /* HAVE_THREADS */ + +int av_thread_message_queue_send(AVThreadMessageQueue *mq, + void *msg, + unsigned flags) +{ +#if HAVE_THREADS + int ret; + + pthread_mutex_lock(&mq->lock); + ret = av_thread_message_queue_send_locked(mq, msg, flags); + pthread_mutex_unlock(&mq->lock); + return ret; +#else + return AVERROR(ENOSYS); +#endif /* HAVE_THREADS */ +} + +int av_thread_message_queue_recv(AVThreadMessageQueue *mq, + void *msg, + unsigned flags) +{ +#if HAVE_THREADS + int ret; + + pthread_mutex_lock(&mq->lock); + ret = av_thread_message_queue_recv_locked(mq, msg, flags); + pthread_mutex_unlock(&mq->lock); + return ret; +#else + return AVERROR(ENOSYS); +#endif /* HAVE_THREADS */ +} + +void av_thread_message_queue_set_err_send(AVThreadMessageQueue *mq, + int err) +{ +#if HAVE_THREADS + pthread_mutex_lock(&mq->lock); + mq->err_send = err; + pthread_cond_broadcast(&mq->cond); + pthread_mutex_unlock(&mq->lock); +#endif /* HAVE_THREADS */ +} + +void av_thread_message_queue_set_err_recv(AVThreadMessageQueue *mq, + int err) +{ +#if HAVE_THREADS + pthread_mutex_lock(&mq->lock); + mq->err_recv = err; + pthread_cond_broadcast(&mq->cond); + pthread_mutex_unlock(&mq->lock); +#endif /* HAVE_THREADS */ +} |