[Mesa-dev] [PATCH 01/11] mesa: Add support for glGetProgramiv pnames for UBOs.

[Brian Paul]

On 07/20/2012 04:33 PM, Eric Anholt wrote:
> Fixes piglit ARB_uniform_buffer_object/getprogramiv.
> ---
>   src/mesa/main/shaderapi.c |   19 +++++++++++++++++++
>   1 file changed, 19 insertions(+)
>
> diff --git a/src/mesa/main/shaderapi.c b/src/mesa/main/shaderapi.c
> index 6927368..f381915 100644
> --- a/src/mesa/main/shaderapi.c
> +++ b/src/mesa/main/shaderapi.c
> @@ -542,6 +542,25 @@ get_programiv(struct gl_context *ctx, GLuint program, GLenum pname, GLint *param
>         *params = shProg->Geom.OutputType;
>         break;
>   #endif
> +   case GL_ACTIVE_UNIFORM_BLOCK_MAX_NAME_LENGTH: {
> +      unsigned i;
> +      GLint max_len = 0;
> +
> +      for (i = 0; i<  shProg->NumUniformBlocks; i++) {
> +	 /* Add one for the terminating NUL character.
> +	  */
> +	 const GLint len = strlen(shProg->UniformBlocks[i].Name) + 1;
> +
> +	 if (len>  max_len)
> +	    max_len = len;
> +      }
> +
> +      *params = max_len;
> +      break;
> +   }
> +   case GL_ACTIVE_UNIFORM_BLOCKS:
> +      *params = shProg->NumUniformBlocks;
> +      break;
>      default:
>         _mesa_error(ctx, GL_INVALID_ENUM, "glGetProgramiv(pname)");
>         return;

It looks like these new cases (and the existing cases for geometry 
shaders and transform feedback) need extension tests:

if (!ctx->Extensions.ARB_uniform_buffer_object) {
    _mesa_error(ctx, GL_INVALID_ENUM, "glGetProgramiv");
    return;
}

Since there would be a quite a few of these, a goto-error handler at 
the end of the function would be good.

-Brian