[FFmpeg-devel] [PATCH 04/13] lavc: Deprecate av_hwaccel_next() and av_register_hwaccel()

[Philip Langdale]

On Sat, 18 Nov 2017 18:47:04 +0000
Mark Thompson <sw at jkqxz.net> wrote:

> ---
>  doc/APIchanges       |  4 ++++
>  libavcodec/avcodec.h | 13 +++++++++++++
>  libavcodec/utils.c   | 16 +++++-----------
>  libavcodec/version.h |  3 +++
>  4 files changed, 25 insertions(+), 11 deletions(-)
> 
> diff --git a/doc/APIchanges b/doc/APIchanges
> index a3c5e21765..547d0019ba 100644
> --- a/doc/APIchanges
> +++ b/doc/APIchanges
> @@ -16,6 +16,10 @@ libavutil:     2017-10-21
>  API changes, most recent first:
>  
>  2017-xx-xx - xxxxxxx - lavc 58.x+1.0 - avcodec.h
> +  Deprecate user visibility of the AVHWAccel structure and the
> functions
> +  av_register_hwaccel() and av_hwaccel_next().
> +
> +2017-xx-xx - xxxxxxx - lavc 58.x+1.0 - avcodec.h
>    Add AVCodecHWConfig and avcodec_get_hw_config().
>  
>  2017-xx-xx - xxxxxxx - lavc 58.3.100 - avcodec.h
> diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
> index fb18f46ea2..c05dbfe777 100644
> --- a/libavcodec/avcodec.h
> +++ b/libavcodec/avcodec.h
> @@ -3489,6 +3489,10 @@ const AVCodecHWConfig
> *avcodec_get_hw_config(const AVCodec *codec, int index); 
>  /**
>   * @defgroup lavc_hwaccel AVHWAccel
> + *
> + * @note  Nothing in this structure should be accessed by the user.
> At some
> + *        point in future it will not be externally visible at all.
> + *
>   * @{
>   */
>  typedef struct AVHWAccel {
> @@ -5874,17 +5878,26 @@ void av_fast_padded_mallocz(void *ptr,
> unsigned int *size, size_t min_size); */
>  unsigned int av_xiphlacing(unsigned char *s, unsigned int v);
>  
> +#if FF_API_USER_VISIBLE_AVHWACCEL
>  /**
>   * Register the hardware accelerator hwaccel.
> + *
> + * @deprecated  This function doesn't do anything.
>   */
> +attribute_deprecated
>  void av_register_hwaccel(AVHWAccel *hwaccel);
>  
>  /**
>   * If hwaccel is NULL, returns the first registered hardware
> accelerator,
>   * if hwaccel is non-NULL, returns the next registered hardware
> accelerator
>   * after hwaccel, or NULL if hwaccel is the last one.
> + *
> + * @deprecated  AVHWaccel structures contain no user-serviceable
> parts, so
> + *              this function should not be used.
>   */
> +attribute_deprecated
>  AVHWAccel *av_hwaccel_next(const AVHWAccel *hwaccel);
> +#endif
>  
>  
>  /**
> diff --git a/libavcodec/utils.c b/libavcodec/utils.c
> index 01bf7556f7..417ebcb770 100644
> --- a/libavcodec/utils.c
> +++ b/libavcodec/utils.c
> @@ -1897,22 +1897,16 @@ const AVCodecHWConfig
> *avcodec_get_hw_config(const AVCodec *codec, int index) return
> &codec->hw_configs[index]->public; }
>  
> -static AVHWAccel *first_hwaccel = NULL;
> -static AVHWAccel **last_hwaccel = &first_hwaccel;
> -
> -void av_register_hwaccel(AVHWAccel *hwaccel)
> +#if FF_API_USER_VISIBLE_AVHWACCEL
> +AVHWAccel *av_hwaccel_next(const AVHWAccel *hwaccel)
>  {
> -    AVHWAccel **p = last_hwaccel;
> -    hwaccel->next = NULL;
> -    while(*p || avpriv_atomic_ptr_cas((void * volatile *)p, NULL,
> hwaccel))
> -        p = &(*p)->next;
> -    last_hwaccel = &hwaccel->next;
> +    return NULL;
>  }
>  
> -AVHWAccel *av_hwaccel_next(const AVHWAccel *hwaccel)
> +void av_register_hwaccel(AVHWAccel *hwaccel)
>  {
> -    return hwaccel ? hwaccel->next : first_hwaccel;
>  }
> +#endif
>  
>  int av_lockmgr_register(int (*cb)(void **mutex, enum AVLockOp op))
>  {
> diff --git a/libavcodec/version.h b/libavcodec/version.h
> index 5b25a9a8ac..693f67386c 100644
> --- a/libavcodec/version.h
> +++ b/libavcodec/version.h
> @@ -123,6 +123,9 @@
>  #ifndef FF_API_CODEC_GET_SET
>  #define FF_API_CODEC_GET_SET     (LIBAVCODEC_VERSION_MAJOR < 59)
>  #endif
> +#ifndef FF_API_USER_VISIBLE_AVHWACCEL
> +#define FF_API_USER_VISIBLE_AVHWACCEL (LIBAVCODEC_VERSION_MAJOR < 60)
> +#endif
>  
>  
>  #endif /* AVCODEC_VERSION_H */

LGTM


--phil