[FFmpeg-devel] [PATCH 1/2] avutil/random_seed: add av_random()

[James Almer]

On 7/4/2023 4:59 PM, Anton Khirnov wrote:
>>
>> Not if any of the functions above were called but failed to fill the buffer.
>>
>> I could add return AVERROR(ENOSYS) to the HAVE_UNISTD_H block, and
>> return AVERROR_INVALIDDATA outside.
> 
> AVERROR_INVALIDDATA is defined as 'Invalid data found when processing
> input'.
> This function does not process any input, so IMO that code never makes
> sense for it.
> 
> I'd say make it ENOSYS, AVERROR_UNKNOWN, or keep around one of
> individual method errors.

For the cases read() is used for /dev/random/, i can return 
AVERROR(errno), given the doxy states read() returns -1 on error and 
sets errno to some value. Although if it succeeds and returns a value 
smaller than len i would need to return AVERROR_UNKNOWN like you suggested.

RAND_bytes from OpenSSL returns 0 or -1 on error, so nothing i can 
propagate.