[FFmpeg-devel] [PATCH] install aes.h, des.h and rc4.h

[Reimar Döffinger]

On Fri, Feb 06, 2009 at 10:33:00PM +0100, Michael Niedermayer wrote:
> On Fri, Feb 06, 2009 at 09:53:16PM +0100, Reimar D?ffinger wrote:
> > But maybe we can find a better solution.
> > What about a
> > void *av_alloca(uint8_t *);
> > Usage would be
> > uint8_t buffer[size + AV_ALLOCA_PADDING];
> > struct AVAES *a = av_alloca(buffer);
> > 
> > Does that seem like it might make a good solution or does it have
> > serious issues?
> 
> its not particularely pretty and something should be done to make it
> less error prone, also no function call should happen just a macro
>  or inline function

I did intend to make the function static inline.
I think it will always ugly, though maybe something like (untested)
#define AV_STACK_VAR(type, name, size) \
    uint8_t name ff_alloca_##name##_buffer[size + 16]; \
    type name = ff_alloca_##name##_buffer + ((-(long)ff_alloca_##name##_buffer - 1)&15) + 1;

fits your idea better?

Greetings,
Reimar D?ffinger