[FFmpeg-devel] [PATCH] lavu/fifo: add av_fifo_alloc_array function

[James Almer]

On 10/05/14 3:15 AM, Lukasz Marek wrote:
> TODO: minor bump and doc/APIchanges update
> 
> Allows to alloc fifo buffer by passing
> number of elements and size of element.
> 
> Signed-off-by: Lukasz Marek <lukasz.m.luki2 at gmail.com>
> ---
>  libavutil/fifo.c | 27 +++++++++++++++++++++------
>  libavutil/fifo.h |  8 ++++++++
>  2 files changed, 29 insertions(+), 6 deletions(-)
> 
> diff --git a/libavutil/fifo.c b/libavutil/fifo.c
> index e35237c..5c82d09 100644
> --- a/libavutil/fifo.c
> +++ b/libavutil/fifo.c
> @@ -24,19 +24,34 @@
>  #include "common.h"
>  #include "fifo.h"
>  
> -AVFifoBuffer *av_fifo_alloc(unsigned int size)
> +static AVFifoBuffer *av_fifo_alloc_common(void *buffer, size_t size)

If it's static it shouldn't have the av_ prefix.
Rename it to alloc_common() or similar before pushing.

>  {
> -    AVFifoBuffer *f = av_mallocz(sizeof(AVFifoBuffer));
> -    if (!f)
> +    AVFifoBuffer *f;
> +    if (!buffer)
> +        return NULL;
> +    f = av_mallocz(sizeof(AVFifoBuffer));
> +    if (!f) {
> +        av_free(buffer);
>          return NULL;
> -    f->buffer = av_malloc(size);
> +    }
> +    f->buffer = buffer;
>      f->end    = f->buffer + size;
>      av_fifo_reset(f);
> -    if (!f->buffer)
> -        av_freep(&f);
>      return f;
>  }
>  
> +AVFifoBuffer *av_fifo_alloc(unsigned int size)
> +{
> +    void *buffer = av_malloc(size);
> +    return av_fifo_alloc_common(buffer, size);
> +}
> +
> +AVFifoBuffer *av_fifo_alloc_array(size_t nmemb, size_t size)
> +{
> +    void *buffer = av_malloc_array(nmemb, size);
> +    return av_fifo_alloc_common(buffer, nmemb * size);
> +}
> +
>  void av_fifo_free(AVFifoBuffer *f)
>  {
>      if (f) {
> diff --git a/libavutil/fifo.h b/libavutil/fifo.h
> index 66fb48a..f3bdcbc 100644
> --- a/libavutil/fifo.h
> +++ b/libavutil/fifo.h
> @@ -42,6 +42,14 @@ typedef struct AVFifoBuffer {
>  AVFifoBuffer *av_fifo_alloc(unsigned int size);
>  
>  /**
> + * Initialize an AVFifoBuffer.
> + * @param nmemb number of elements
> + * @param size  size of the single element
> + * @return AVFifoBuffer or NULL in case of memory allocation failure
> + */
> +AVFifoBuffer *av_fifo_alloc_array(size_t nmemb, size_t size);
> +
> +/**
>   * Free an AVFifoBuffer.
>   * @param f AVFifoBuffer to free
>   */
>