[FFmpeg-devel] [PATCH] avpacket: ABI bump additions

[Lynne]

Apr 26, 2021, 03:27 by andreas.rheinhardt at outlook.com:

> Lynne:
>
>> From 097aed2ac33dda0bb2052d8b0402711ce95079ba Mon Sep 17 00:00:00 2001
>> From: Lynne <dev at lynne.ee>
>> Date: Sat, 23 Jan 2021 19:56:18 +0100
>> Subject: [PATCH] avpacket: ABI bump additions
>>
>> ---
>>  libavcodec/avpacket.c |  5 +++++
>>  libavcodec/packet.h   | 21 +++++++++++++++++++++
>>  2 files changed, 26 insertions(+)
>>
>> diff --git a/libavcodec/avpacket.c b/libavcodec/avpacket.c
>> index e32c467586..03b73b3b53 100644
>> --- a/libavcodec/avpacket.c
>> +++ b/libavcodec/avpacket.c
>> @@ -382,6 +382,10 @@ int av_packet_copy_props(AVPacket *dst, const AVPacket *src)
>>  dst->flags                = src->flags;
>>  dst->stream_index         = src->stream_index;
>>  
>> +    i = av_buffer_replace(&dst->opaque_ref, src->opaque_ref);
>> +    if (i < 0)
>> +        return i;
>>
>
> 1. Don't use i here; add a new variable.
> 2. Up until now, av_packet_ref() and av_packet_copy_props() treat the
> destination packet as uninitialized and make no attempt at unreferencing
> its content; yet you try to reuse opaque_ref. Even worse, you might
> return potentially dangerous packets: If the properties were
> uninitialized and av_packet_copy_props() failed, then the caller were
> not allowed to unreference the packet even when the non-properties were
> set to sane values. The easiest way to fix this is to move setting
> opaque ref to the place after initializing side_data below and either
> set dst->opaque_ref to NULL before av_buffer_replace() or to not use
> av_buffer_replace(). It may also be best to unref it again if copying
> side data fails.
>
>> +
>>  dst->side_data            = NULL;
>>  dst->side_data_elems      = 0;
>>  for (i = 0; i < src->side_data_elems; i++) {
>> @@ -403,6 +407,7 @@ int av_packet_copy_props(AVPacket *dst, const AVPacket *src)
>>  void av_packet_unref(AVPacket *pkt)
>>  {
>>  av_packet_free_side_data(pkt);
>> +    av_buffer_unref(&pkt->opaque_ref);
>>  av_buffer_unref(&pkt->buf);
>>  get_packet_defaults(pkt);
>>  }
>> diff --git a/libavcodec/packet.h b/libavcodec/packet.h
>> index fad8341c12..c29ad18a2b 100644
>> --- a/libavcodec/packet.h
>> +++ b/libavcodec/packet.h
>> @@ -383,6 +383,27 @@ typedef struct AVPacket {
>>  int64_t duration;
>>  
>>  int64_t pos;                            ///< byte position in stream, -1 if unknown
>> +
>> +    /**
>> +     * for some private data of the user
>> +     */
>> +    void *opaque;
>>
>
> The corresponding AVFrame field is copied when copying props.
>

Fixed both, thanks. Also copied the time_base field and made av_init_packet()
initialize all fields.
Patch attached. Sorry it's taking me so long to work on this and the Vulkan ABI changes.

-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0001-avpacket-ABI-bump-additions.patch
Type: text/x-patch
Size: 3151 bytes
Desc: not available
URL: <https://ffmpeg.org/pipermail/ffmpeg-devel/attachments/20210603/3d63d518/attachment.bin>