ffserver&ffm: Fixed issues preventing ffserver write_index and files_size from being set correctly which was breaking ffserver streaming.

I discovered that ffserver streaming was broken (it seems like it has been since 20th November) and I opened a ticket for this (https://trac.ffmpeg.org/ticket/5250 <https://trac.ffmpeg.org/ticket/5250>).

I spent yesterday learning git bisect (with the kind help of cehoyos) to painstakingly track down the cause. This was made more difficult due to the presence of a segfault in ffserver during the period where the bug was introduced so I first had to identify when and how that was fixed and then retrospectively apply that fix again for each step of the second git bisect to find the actual bug.

Anyway, the fruits of my labour are the innocent looking patch below to correct a couple of typos and define a valid range for two variables.
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

lavf/riffenc: Write space for palette
tests/ref/vsynth: Update 1 bpp files for pal8
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Timothy Gu <timothygu99@gmail.com>

This commit adds support for the (simple, allowed in the spec, but
inferior in quality) Haar wavelet transforms.
Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>

Avoid invalid memory read/crash when frame offset >= 0xfffffff8.
Base64-encoded example: AAABADAwMDAwMAAAMAAwMDAw/P///w==
(The previous commit verifies that p->buf_size >= 22.)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

Fix cases where unknown data (data beyond p->buf_size) could produce a
higher ico probe score than if the unknown data was known and valid.
For example:
    Header:  OK, 2 frames
    Frame 0: Unknown (offset points beyond end of probe buffer)
    Frame 1: Invalid
Previously this example had a score of 25, even though the score would
be 1 if the unknown frame was known to be valid or 0 if it was known
to be invalid.  For this example the score is now 1.
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

Codec options of streams detected during avformat_find_stream_info are not set
therefore without this patch we initialize the encoders with decoder info
based on decoders without options.

This cause problems for probed DVB teletext streams where
avctx->subtitle_header depend on the txt_format setting.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Marton Balint <cus@passwd.hu>

Signed-off-by: Marton Balint <cus@passwd.hu>

Signed-off-by: Marton Balint <cus@passwd.hu>

Reported and tested by Nicolas George.
Fixes ticket #5249.

They will now compile if avcodec is disabled
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: James Almer <jamrial@gmail.com>

This can be made more efficient, but first and the main goal of this change is to
store it at all
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

Signed-off-by: Paul B Mahol <onemda@gmail.com>

Fixes race condition causing artifacts
Fixes Ticket4122
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

Revert "configure: Don't enable examples when --disable-everything is used"
reverted as the problematic commit will be reverted too
This reverts commit 02dfa64c.

Revert "Merge commit 'a2bb771a'"
This reverts commit e8ebcb00, reversing
changes made to 3bff005b.

Revert "Merge commit '21c750f2'"
This reverts commit 470bfab4, reversing
changes made to f97ee815.

Revert "Revert "configure: Revert recent changes to disable-everything""
This reverts commit f97ee815.
Reviewed-by: Hendrik Leppkes <h.leppkes@gmail.com>
Immediate commit suggested by BBB

It is only used in a boolean context. Also clarify its documentation.
Signed-off-by: Moritz Barsnick <barsnick@gmx.net>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

Signed-off-by: Paul B Mahol <onemda@gmail.com>

Fixes integer overflow
Fixes: Ticket5126
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

character sets implemented as defined in https://en.wikipedia.org/wiki/EIA-608#Characters

control codes in a cc stream can be repeated, and must be ignored.
however, repeated characters must not be ignored. the code attempted to
wipe prev_cmd in handle_char to allow repeated characters to be
processed, but prev_cmd would previously get reset _after_ handle_char()

i also moved the prev_cmd reset out from handle_char() so it can be
re-used for special character sets, which _must_ be ignored when
repeated.

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

This resotres old behavior.
Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>

Signed-off-by: Paul B Mahol <onemda@gmail.com>

* commit 'bd49be88':
  avconv_vdpau: use the hwcontext API to simplify code

Tested-by: wm4
Merged-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>

* commit 'a001ce31':
  hwcontext: add a VDPAU implementation
Merged-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>

* commit '89923e41':
  lavu: add a framework for handling hwaccel frames
Merged-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>

* commit '721a4efc':
  buffer: add support for pools using caller data in allocation
Merged-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>

* commit 'c084d6d2':
  buffersrc: default SAR to 0 (unknown) rather than 1
Merged-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>

* commit 'a2bb771a':
  configure: Restore the --enable-everything behaviour
Merged-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>

* commit '5e1beec9':
  configure: Print which libraries will be built
Merged-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>