[flac-dev] about libFLAC/metadata_object.c

[lvqcl]

lvqcl <lvqcl.mail at gmail.com> wrote:

> There are two functions:
>
>      static void vorbiscomment_entry_array_delete_(FLAC__StreamMetadata_VorbisComment_Entry *object_array, unsigned num_comments);
>
> and
>
>      static void cuesheet_track_array_delete_(FLAC__StreamMetadata_CueSheet_Track *object_array, unsigned num_tracks);
>
>
> which first dereference object_array and only then check it for NULL:
>
>              free(object_array[i].indices);
>          ...
>          ...
>          if(0 != object_array)
>              free(object_array);
>
> Currently the condition "if(0 != object_array)" is not necessary because libFLAC
> always checks the first argument of these static functions before calling them.


Another example is in static_metadata_clear() in src\flac\encode.c:

     for(i = 0; i < m->num_metadata; i++)
         if(m->needs_delete[i])
             FLAC__metadata_object_delete(m->metadata[i]);

     if(m->metadata)
         free(m->metadata);
     if(m->needs_delete)
         free(m->needs_delete);

Here m->metadata and m->needs_delete were first dereferenced
and then (unnecessarily) checked against NULL.