Avoid access to uninitialized values, which may result in a crash.

This happens for example in case of option parsing failure, since in that
case the internal AVBprint buffers are not initialized.

Make ffprobe honour codec options, and support stream specifiers like it
is done in ffplay.

In particular, address Trac ticket #1859.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Fix trac ticket #2027.

Fix memleak.

Found by Coverity, should fix CID 733741.

Allow to factorize buffers initialization/release, for all the writers
which use it. Simplify.

Fixes CID733837
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

This fixes 2 warnings

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

This generalizes the previous work on disposition printing.

Disposition flags are shown in a dedicated section, which should improve
output intellegibility, extensibility and filtering operations.

This breaks output syntax with the recently introduced disposition
printing.

Do not make use of ad-hoc "tags" code, introduce a new section flag
SECTION_FLAG_HAS_VARIABLE_FIELDS to deal with the tags in a
content-agnostic way.

This is required by the pending disposition change.

Do not build from scratch the section header for each section, but build
it using the previous level buffer, thus improving efficiency.

Also fix some few corner cases related to numbering which are exposed by
the pending disposition patch.

Do not build from scratch the section header for each section, but build
using the previous level buffer, thus improving efficiency and fix some
few corner cases which are exposed by the pending disposition patch.

Regular section fields nested in a regular section are now prefixed by
the nested section name.

This is required by the pending change related to disposition.

Regular section fields nested in a regular section are now prefixed by
the nested section name.

This is required by the pending change related to disposition.

The use of the macro makes to add new optional fields somewhat harder.

The parameter is no longer used, since the arguments are parsed at the
framework level.

Discard unflexible structure based on the root/chapter/section layout in
favor of a generalized concept of section.

This should allow to represent sections at a generic level of nesting,
and allow subsection fields selection.

Also, simplify the code.

The parameter was never used.

Make writer_print_time() and writer_print_rational() always call
writer_print_int() or writer_print_string(). This way the checks for
determining if the value should be printed or not are consistently
performed in the low level functions.

writer_print_rational() is moved downward in order to avoid a forward
reference.

Simplify/amend the overall logic.

Signed-off-by: Alexander Strasser <eclipse7@gmx.net>

Sync to 3245be95 .

Signed-off-by: Alexander Strasser <eclipse7@gmx.net>

Sync with bac1b31b .

Signed-off-by: Alexander Strasser <eclipse7@gmx.net>

The option is mostly useful to make ffprobe output independent from the
build, and in particular to fix FATE --enable-small failures.

Fix possible crash when long_name is not defined (for example if
--enable-small).

Avoid possible segmentation fault if codec_long_name is defined as
NULL (for example if --enable-small).

Fix regression introduced in 749ddc14.

This info is crucial in knowing which stream to pick in an
automated setup.

Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>