[FFmpeg-devel] [PATCH 1/6] lavu/mem: add av_realloc_reuse() as a replacement for av_fast_realloc()

[Anton Khirnov]

Quoting Tomas Härdin (2022-09-28 13:48:01)
> ons 2022-09-28 klockan 12:48 +0200 skrev Anton Khirnov:
> > 
> > +/**
> > + * Reallocate a data buffer, reusing the existing one if it is large
> > enough.
> > + *
> > + * This function is similar to av_realloc(), but optimized for cases
> > where the
> > + * buffer may grow significantly and is not expected to shrink.
> > + *
> > + * @param[in] ptr Previously allocated buffer, or `NULL`. If `ptr`
> > is `NULL`, a
> > + * new uninitialized buffer is allocated. `ptr` is invalidated when
> > this
> > + * function returns non-`NULL` and must be replaced with its return
> > value.
> > + *
> > + * @param[in,out] size Pointer to the allocated size of buffer
> > `ptr`. This
> > + * function updates `*size` to the new allocated size (which may be
> > larger than
> > + * `min_size`). `*size` is set to 0 on failure.
> > + *
> > + * @param[in] min_size Minimum size in bytes of the returned buffer.
> > + *
> > + * @return
> > + * - An allocated buffer (to be freed with `av_free()`) that is
> > large enough to
> > + *   hold at least `min_size` bytes. The first `*size` (value on
> > entry to this
> > + *   function) bytes of the buffer remain the same as the data in
> > `ptr`, the
> > + *   rest is uninitialized.
> > + * - `NULL` on failure, then `*size` is set to 0 and ptr remains
> > untouched.
> > + *
> > + * @see av_realloc()
> > + * @see av_fast_malloc()
> > + */
> > +void *av_realloc_reuse(void *ptr, size_t *size, size_t min_size);
> 
> Isn't it better to return int like av_realloc_array_reuse() and leave
> *ptr and *size untouched on error just as it does? If we're in the
> business of straightening this all out then having all functions work
> the same is less mental load down the line.

I suppose you're right, it's just more work to convert all the callers.
Will do and resend.

-- 
Anton Khirnov