[IOS] Memory leaks during argument parsing

[tanersener]

Argument parsing methods leaks memory. The following trace belongs to one of the leaks.

   0 libsystem_malloc.dylib malloc_zone_malloc
   1 libsystem_malloc.dylib realloc
   2 mobileffmpeg grow_array
   3 mobileffmpeg split_commandline
   4 mobileffmpeg ffmpeg_parse_options
   5 mobileffmpeg execute
   6 mobileffmpeg mobileffmpeg_execute

The actual cause is reusable nature of internal variables. FFmpeg executable does not perform a full cleanup on abnormal termination and exits without freeing some dynamic parts. But MobileFFmpeg does not call FFmpeg executable and some dynamic blocks remain unfreed.

A common solution is needed for both Android and IOS.

This issue was detected in v2.0 but it looks like all versions are affected from this.

[tanersener]

A detailed analysis proves that successful command execution does not create new leaks, only commands returning a non-zero return value create leaks. The good thing is most of them are small in size, around 16 - 80 bytes per execution.

Additionally, most of them occur inside libavutil because memory allocation operations av_alloc/av_calloc/av_malloc/av_realloc/av_strdup are defined in libavutil/mem.c.

A solution is planned in middle-term.

The following screenshot is captured for IOS during command execution tests.

[github-actions]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[github-actions]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[github-actions]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[github-actions]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[github-actions]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.