[FFmpeg-devel] [PATCH 1/3] avutil/threadmessage: add av_thread_message_flush()

[Clément Bœsch]

From: Clément Bœsch <clement at stupeflix.com>

---
 libavutil/threadmessage.c | 32 ++++++++++++++++++++++++++++++++
 libavutil/threadmessage.h | 12 ++++++++++++
 2 files changed, 44 insertions(+)

diff --git a/libavutil/threadmessage.c b/libavutil/threadmessage.c
index b7fcbe2..66b5fc6 100644
--- a/libavutil/threadmessage.c
+++ b/libavutil/threadmessage.c
@@ -40,6 +40,8 @@ struct AVThreadMessageQueue {
     int err_send;
     int err_recv;
     unsigned elsize;
+    void (*free_func)(void *msg);
+    void *tmp_msg;
 #else
     int dummy;
 #endif
@@ -81,10 +83,21 @@ int av_thread_message_queue_alloc(AVThreadMessageQueue **mq,
 #endif /* HAVE_THREADS */
 }
 
+int av_thread_message_queue_set_free_func(AVThreadMessageQueue *mq,
+                                          void (*free_func)(void *msg))
+{
+    mq->free_func = free_func;
+    av_freep(&mq->tmp_msg);
+    mq->tmp_msg = av_mallocz(mq->elsize);
+    return mq->tmp_msg ? 0 : AVERROR(ENOMEM);
+}
+
 void av_thread_message_queue_free(AVThreadMessageQueue **mq)
 {
 #if HAVE_THREADS
     if (*mq) {
+        av_thread_message_flush(*mq);
+        av_freep(&(*mq)->tmp_msg);
         av_fifo_freep(&(*mq)->fifo);
         pthread_cond_destroy(&(*mq)->cond);
         pthread_mutex_destroy(&(*mq)->lock);
@@ -182,3 +195,22 @@ void av_thread_message_queue_set_err_recv(AVThreadMessageQueue *mq,
     pthread_mutex_unlock(&mq->lock);
 #endif /* HAVE_THREADS */
 }
+
+void av_thread_message_flush(AVThreadMessageQueue *mq)
+{
+#if HAVE_THREADS
+    int used, off;
+
+    pthread_mutex_lock(&mq->lock);
+    used = av_fifo_size(mq->fifo);
+    if (mq->free_func) {
+        for (off = 0; off < used; off += mq->elsize) {
+            av_fifo_generic_peek_at(mq->fifo, mq->tmp_msg, off, mq->elsize, NULL);
+            mq->free_func(mq->tmp_msg);
+        }
+    }
+    av_fifo_drain(mq->fifo, used);
+    pthread_cond_broadcast(&mq->cond);
+    pthread_mutex_unlock(&mq->lock);
+#endif /* HAVE_THREADS */
+}
diff --git a/libavutil/threadmessage.h b/libavutil/threadmessage.h
index a8481d8..c59cb06 100644
--- a/libavutil/threadmessage.h
+++ b/libavutil/threadmessage.h
@@ -88,4 +88,16 @@ void av_thread_message_queue_set_err_send(AVThreadMessageQueue *mq,
 void av_thread_message_queue_set_err_recv(AVThreadMessageQueue *mq,
                                           int err);
 
+/**
+ * Set the optional free message callback function which will be called if an
+ * operation is removing messages from the queue.
+ */
+int av_thread_message_queue_set_free_func(AVThreadMessageQueue *mq,
+                                          void (*free_func)(void *msg));
+
+/**
+ * Flush the message queue
+ */
+void av_thread_message_flush(AVThreadMessageQueue *mq);
+
 #endif /* AVUTIL_THREADMESSAGE_H */
-- 
2.6.2