[FFmpeg-devel] [PATCH v2 1/4] avcodec/allcodecs: make avcodec_register_all thread safe

[James Almer]

On 3/7/2017 11:05 AM, wm4 wrote:
> On Tue, 7 Mar 2017 20:48:13 +0700
> Muhammad Faiz <mfcc64 at gmail.com> wrote:
> 
>> On Tue, Mar 7, 2017 at 4:17 PM, wm4 <nfxjfg at googlemail.com> wrote:
>>> On Tue,  7 Mar 2017 16:01:58 +0700
>>> Muhammad Faiz <mfcc64 at gmail.com> wrote:
>>>  
>>>> use ff_thread_once
>>>>
>>>> Suggested-by: wm4 <nfxjfg at googlemail.com>
>>>> Signed-off-by: Muhammad Faiz <mfcc64 at gmail.com>
>>>> ---
>>>>  libavcodec/allcodecs.c | 16 +++++++++-------
>>>>  1 file changed, 9 insertions(+), 7 deletions(-)
>>>>
>>>> diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c
>>>> index eee322b..6ec7e79 100644
>>>> --- a/libavcodec/allcodecs.c
>>>> +++ b/libavcodec/allcodecs.c
>>>> @@ -25,6 +25,7 @@
>>>>   */
>>>>
>>>>  #include "config.h"
>>>> +#include "libavutil/thread.h"
>>>>  #include "avcodec.h"
>>>>  #include "version.h"
>>>>
>>>> @@ -58,14 +59,8 @@
>>>>              av_register_codec_parser(&ff_##x##_parser);                 \
>>>>      }
>>>>
>>>> -void avcodec_register_all(void)
>>>> +static void register_all(void)
>>>>  {
>>>> -    static int initialized;
>>>> -
>>>> -    if (initialized)
>>>> -        return;
>>>> -    initialized = 1;
>>>> -
>>>>      /* hardware accelerators */
>>>>      REGISTER_HWACCEL(H263_VAAPI,        h263_vaapi);
>>>>      REGISTER_HWACCEL(H263_VIDEOTOOLBOX, h263_videotoolbox);
>>>> @@ -717,3 +712,10 @@ void avcodec_register_all(void)
>>>>      REGISTER_PARSER(VP9,                vp9);
>>>>      REGISTER_PARSER(XMA,                xma);
>>>>  }
>>>> +
>>>> +void avcodec_register_all(void)
>>>> +{
>>>> +    static AVOnce control = AV_ONCE_INIT;
>>>> +
>>>> +    ff_thread_once(&control, register_all);
>>>> +}  
>>>
>>> Looks all good to me.
>>>
>>> Of course this doesn't change that the thread-safety of this whole
>>> "list of components" code is still questionable, but it doesn't hurt to
>>> do this either.  
>>
>> Patchset applied.
>>
>> Thank's.
> 
> I'm not the maintainer, though. Looks like you violated the development
> rules. (Not that I blame you, it's just an observation.)

There's no listed maintainer for all*.c files, so your review was enough
for a simple patchset like this.