#10837: mp3_read_header might break seekback
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Reporter: noseglid | Type: defect
Status: new | Priority: normal
Component: avformat | Version: unspecified
Keywords: mp3 | Blocked By:
Blocking: | Reproduced by developer: 0
Analyzed by developer: 0 |
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I've found an issue in ffmpeg 6.x.x and greater - and I've tracked it down
to this commit:
https://git.ffmpeg.org/gitweb/ffmpeg.git/commitdiff/0d17f5228f4d3854066ec1001f69c7d1714b0df9
What happens here is that it tries to minimize the amount of seeks - but
this breaks the `ffio_ensure_seekback` calls.
`ffio_ensure_seekback` ensures seekback from the current position in the
buffer.
As the loop no longer seeks back to the beginning of the buffer every
iteration of, it might move the buffer ahead of `off`.
Before returning, it tries to reset the position to `off` or `off+i`
depending if there's junk or not. If the buffer has moved ahead of this it
will either;
* Invoke a real seek if there is a `seek` function
* Fail with `AVERROR(EPIPE)` if there is not.
I think either this commit has to be reversed - or it must ensure seekback
for the maximum bytes it might read (64*1024+4) before the loop starts.
--
Ticket URL: <https://trac.ffmpeg.org/ticket/10837>
FFmpeg <https://ffmpeg.org>
FFmpeg issue tracker
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