[FFmpeg-devel] [PATCH v2] fftools/ffmpeg_mux: fix reporting muxer EOF as error

[Marton Balint]

On Sat, 22 Apr 2023, Anton Khirnov wrote:

> Quoting Zhao Zhili (2023-04-22 14:56:34)
>> From: Zhao Zhili <zhilizhao at tencent.com>
>>
>> Fix #10327.
>>
>> Signed-off-by: Zhao Zhili <zhilizhao at tencent.com>
>> ---
>>  fftools/ffmpeg_mux.c | 12 +++++++++---
>>  1 file changed, 9 insertions(+), 3 deletions(-)
>>
>> diff --git a/fftools/ffmpeg_mux.c b/fftools/ffmpeg_mux.c
>> index a2e8873ad2..0e1a5d7dc5 100644
>> --- a/fftools/ffmpeg_mux.c
>> +++ b/fftools/ffmpeg_mux.c
>> @@ -214,9 +214,15 @@ static void *muxer_thread(void *arg)
>>          ost = of->streams[stream_idx];
>>          ret = sync_queue_process(mux, ost, ret < 0 ? NULL : pkt, &stream_eof);
>>          av_packet_unref(pkt);
>> -        if (ret == AVERROR_EOF && stream_eof)
>> -            tq_receive_finish(mux->tq, stream_idx);
>> -        else if (ret < 0) {
>> +        if (ret == AVERROR_EOF) {
>> +            if (stream_eof) {
>> +                tq_receive_finish(mux->tq, stream_idx);
>> +            } else {
>> +                av_log(mux, AV_LOG_VERBOSE, "Muxer %s\n", av_err2str(ret));
>
> That seems unnecesarily convoluted, given that we _know_ the error to be
> EOF here. Also, please make it "Muxer returned EOF" to make it clear
> what exactly is the source of EOF.
>
> Otherwise ok, feel free to push with this change.

This seems like yet another clash of AVERROR_EOF error codes coming from
different places with different semantics. For 
av_interleaved_write_frame(), AVERROR_EOF is an error condition, so 
file encoding should fail, but after this patch it will not fail, just 
simply end, because you assume it is legitimately coming from the filesize 
check... This should be fixed somehow, e.g. use a special error code for 
the filesize check and only handle that as a legitimate EOF.

Regards,
Marton