[FFmpeg-devel] [PATCH 1/6] avcodec/avpacket: add av_packet_make_ref()

[James Almer]

It works as a drop in replacement for the deprecated av_dup_packet(),
to ensure a packet is reference counted.

Signed-off-by: James Almer <jamrial at gmail.com>
---
Better name welcome.

 libavcodec/avcodec.h  | 18 +++++++++++++++++-
 libavcodec/avpacket.c | 18 ++++++++++++++++++
 2 files changed, 35 insertions(+), 1 deletion(-)

diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index 495242faf0..eb3fe4e428 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -4360,7 +4360,7 @@ int av_packet_from_data(AVPacket *pkt, uint8_t *data, int size);
  * @warning This is a hack - the packet memory allocation stuff is broken. The
  * packet is allocated if it was not really allocated.
  *
- * @deprecated Use av_packet_ref
+ * @deprecated Use av_packet_ref or av_packet_make_ref
  */
 attribute_deprecated
 int av_dup_packet(AVPacket *pkt);
@@ -4531,6 +4531,22 @@ void av_packet_move_ref(AVPacket *dst, AVPacket *src);
  */
 int av_packet_copy_props(AVPacket *dst, const AVPacket *src);
 
+/**
+ * Ensure the data described by a given packet is reference counted.
+ *
+ * @note This function does no ensure that the reference will be writable.
+ *       Use av_packet_make_writable instead for that purpose.
+ *
+ * @see av_packet_ref
+ * @see av_packet_make_writable
+ *
+ * @param pkt packet whose data should be made reference counted.
+ *
+ * @return 0 on success, a negative AVERROR on error. On failure, the
+ *         packet is unchanged.
+ */
+int av_packet_make_ref(AVPacket *pkt);
+
 /**
  * Create a writable reference for the data described by a given packet,
  * avoiding data copy if possible.
diff --git a/libavcodec/avpacket.c b/libavcodec/avpacket.c
index 7faa082395..a6d2e6eb74 100644
--- a/libavcodec/avpacket.c
+++ b/libavcodec/avpacket.c
@@ -655,6 +655,24 @@ void av_packet_move_ref(AVPacket *dst, AVPacket *src)
     src->size = 0;
 }
 
+int av_packet_make_ref(AVPacket *pkt)
+{
+    int ret;
+
+    if (pkt->buf)
+        return 0;
+
+    ret = packet_alloc(&pkt->buf, pkt->size);
+    if (ret < 0)
+        return ret;
+    if (pkt->size)
+        memcpy(pkt->buf->data, pkt->data, pkt->size);
+
+    pkt->data = pkt->buf->data;
+
+    return 0;
+}
+
 int av_packet_make_writable(AVPacket *pkt)
 {
     AVBufferRef *buf = NULL;
-- 
2.16.2