[FFmpeg-devel] [PATCH 1/2] lavu: add thread message API.
Nicolas George
george at nsup.org
Thu Feb 20 16:22:13 CET 2014
TODO minor bump and APIchanges entry.
Signed-off-by: Nicolas George <george at nsup.org>
---
libavutil/Makefile | 2 +
libavutil/threadmessage.c | 172 ++++++++++++++++++++++++++++++++++++++++++++++
libavutil/threadmessage.h | 92 +++++++++++++++++++++++++
3 files changed, 266 insertions(+)
create mode 100644 libavutil/threadmessage.c
create mode 100644 libavutil/threadmessage.h
diff --git a/libavutil/Makefile b/libavutil/Makefile
index e4ee47c..4b173d8 100644
--- a/libavutil/Makefile
+++ b/libavutil/Makefile
@@ -50,6 +50,7 @@ HEADERS = adler32.h \
sha.h \
sha512.h \
stereo3d.h \
+ threadmessage.h \
time.h \
timecode.h \
timestamp.h \
@@ -115,6 +116,7 @@ OBJS = adler32.o \
sha.o \
sha512.o \
stereo3d.o \
+ threadmessage.o \
time.o \
timecode.o \
tree.o \
diff --git a/libavutil/threadmessage.c b/libavutil/threadmessage.c
new file mode 100644
index 0000000..5389246
--- /dev/null
+++ b/libavutil/threadmessage.c
@@ -0,0 +1,172 @@
+/*
+ * 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 <pthread.h>
+#include "fifo.h"
+#include "threadmessage.h"
+
+#include <pthread.h>
+#include "fifo.h"
+
+struct AVThreadMessageQueue {
+ AVFifoBuffer *fifo;
+ pthread_mutex_t lock;
+ pthread_cond_t cond;
+ int err_send;
+ int err_recv;
+ unsigned elsize;
+};
+
+int av_thread_message_queue_alloc(AVThreadMessageQueue **mq,
+ unsigned elsize,
+ unsigned nelem)
+{
+#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
+ return AVERROR(ENOSYS);
+#endif /* HAVE_THREADS */
+}
+
+void av_thread_message_queue_free(AVThreadMessageQueue **mq)
+{
+ if (*mq) {
+ av_fifo_free((*mq)->fifo);
+#if HAVE_THREADS
+ pthread_cond_destroy(&(*mq)->cond);
+ pthread_mutex_destroy(&(*mq)->lock);
+#endif
+ av_freep(mq);
+ }
+}
+
+#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 */
+}
diff --git a/libavutil/threadmessage.h b/libavutil/threadmessage.h
new file mode 100644
index 0000000..0c77bcf
--- /dev/null
+++ b/libavutil/threadmessage.h
@@ -0,0 +1,92 @@
+/*
+ * 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
+ */
+
+#ifndef AVUTIL_THREADMESSAGE_H
+#define AVUTIL_THREADMESSAGE_H
+
+#include <pthread.h>
+#include "fifo.h"
+
+typedef struct AVThreadMessageQueue AVThreadMessageQueue;
+
+typedef enum AVThreadMessageFlags {
+
+ /**
+ * Perform non-blocking operation.
+ * If this flag is set, send and recv operations are non-blocking and
+ * return AVERROR(EAGAIN) immediately if they can not proceed.
+ */
+ AV_THREAD_MESSAGE_NONBLOCK = 1,
+
+} AVThreadMessageFlags;
+
+/**
+ * Allocate a new message queue.
+ *
+ * @param mq pointer to the message queue
+ * @param elsize size of each element in the queue
+ * @param nelem minimum number of elements in the queue
+ * @return >=0 for success; <0 for error, in particular AVERROR(ENOSYS) if
+ * lavu was built without thread support
+ */
+int av_thread_message_queue_alloc(AVThreadMessageQueue **mq,
+ unsigned elsize,
+ unsigned nelem);
+
+/**
+ * Free a message queue.
+ */
+void av_thread_message_queue_free(AVThreadMessageQueue **mq);
+
+/**
+ * Send a message on the queue.
+ */
+int av_thread_message_queue_send(AVThreadMessageQueue *mq,
+ void *msg,
+ unsigned flags);
+
+/**
+ * Receive a message from the queue.
+ */
+int av_thread_message_queue_recv(AVThreadMessageQueue *mq,
+ void *msg,
+ unsigned flags);
+
+/**
+ * Set the sending error code.
+ *
+ * If the error code is set to non-zero, av_thread_message_queue_recv() will
+ * return it immediately when there are no longer available messages.
+ * Conventional values, such as AVERROR_EOF or AVERROR(EAGAIN), can be used
+ * to cause the receiving thread to stop or suspend its operation.
+ */
+void av_thread_message_queue_set_err_send(AVThreadMessageQueue *mq,
+ int err);
+
+/**
+ * Set the receiving error code.
+ *
+ * If the error code is set to non-zero, av_thread_message_queue_send() will
+ * return it immediately. Conventional values, such as AVERROR_EOF or
+ * AVERROR(EAGAIN), can be used to cause the sending thread to stop or
+ * suspend its operation.
+ */
+void av_thread_message_queue_set_err_recv(AVThreadMessageQueue *mq,
+ int err);
+
+#endif /* AVUTIL_THREADMESSAGE_H */
--
1.8.5.3
More information about the ffmpeg-devel
mailing list