[Mesa-dev] [PATCH] mesa: Filter glGetProgramiv pnames based on available extensions

[Brian Paul]

On 08/24/2012 09:42 AM, Ian Romanick wrote:
> From: Ian Romanick<ian.d.romanick at intel.com>
>
> Previously you could always glGetProgramiv one of the transform feedback
> or geometry shader enums even if the extension wasn't supported.
>
> In addtion, this reverts part of bda6ad27.  I think the hunks involving
> GL_PROGRAM_BINARY_LENGTH_OES were spurious.  Mesa has no support for any
> other part of GL_OES_get_program_binary.
>
> v2: Remove redundant return in get_programiv based on review feedback
> from Matt Turner.
>
> v3: Correctly handle UBO related enums.
>
> Signed-off-by: Ian Romanick<ian.d.romanick at intel.com>
> Cc: Brian Paul<brianp at vmware.com>
> ---
>   src/mesa/main/shaderapi.c |   66 ++++++++++++++++++++++++--------------------
>   1 files changed, 36 insertions(+), 30 deletions(-)
>
> diff --git a/src/mesa/main/shaderapi.c b/src/mesa/main/shaderapi.c
> index caeb965..1e69458 100644
> --- a/src/mesa/main/shaderapi.c
> +++ b/src/mesa/main/shaderapi.c
> @@ -481,28 +481,28 @@ get_programiv(struct gl_context *ctx, GLuint program, GLenum pname, GLint *param
>      switch (pname) {
>      case GL_DELETE_STATUS:
>         *params = shProg->DeletePending;
> -      break;
> +      return;
>      case GL_LINK_STATUS:
>         *params = shProg->LinkStatus;
> -      break;
> +      return;
>      case GL_VALIDATE_STATUS:
>         *params = shProg->Validated;
> -      break;
> +      return;
>      case GL_INFO_LOG_LENGTH:
>         *params = shProg->InfoLog ? strlen(shProg->InfoLog) + 1 : 0;
> -      break;
> +      return;
>      case GL_ATTACHED_SHADERS:
>         *params = shProg->NumShaders;
> -      break;
> +      return;
>      case GL_ACTIVE_ATTRIBUTES:
>         *params = _mesa_count_active_attribs(shProg);
> -      break;
> +      return;
>      case GL_ACTIVE_ATTRIBUTE_MAX_LENGTH:
>         *params = _mesa_longest_attribute_name_length(shProg);
> -      break;
> +      return;
>      case GL_ACTIVE_UNIFORMS:
>         *params = shProg->NumUserUniformStorage;
> -      break;
> +      return;
>      case GL_ACTIVE_UNIFORM_MAX_LENGTH: {
>         unsigned i;
>         GLint max_len = 0;
> @@ -517,41 +517,48 @@ get_programiv(struct gl_context *ctx, GLuint program, GLenum pname, GLint *param
>         }
>
>         *params = max_len;
> -      break;
> +      return;
>      }
> -   case GL_PROGRAM_BINARY_LENGTH_OES:
> -      *params = 0;
> -      break;
>   #if FEATURE_EXT_transform_feedback
>      case GL_TRANSFORM_FEEDBACK_VARYINGS:
> +      if (!ctx->Extensions.EXT_transform_feedback)
> +         break;
>         *params = shProg->TransformFeedback.NumVarying;
> -      break;
> +      return;
>      case GL_TRANSFORM_FEEDBACK_VARYING_MAX_LENGTH:
> +      if (!ctx->Extensions.EXT_transform_feedback)
> +         break;
>         *params = longest_feedback_varying_name(shProg) + 1;
> -      break;
> +      return;
>      case GL_TRANSFORM_FEEDBACK_BUFFER_MODE:
> +      if (!ctx->Extensions.EXT_transform_feedback)
> +         break;
>         *params = shProg->TransformFeedback.BufferMode;
> -      break;
> +      return;
>   #endif
>   #if FEATURE_ARB_geometry_shader4
>      case GL_GEOMETRY_VERTICES_OUT_ARB:
> +      if (!ctx->Extensions.ARB_geometry_shader4)
> +         break;
>         *params = shProg->Geom.VerticesOut;
> -      break;
> +      return;
>      case GL_GEOMETRY_INPUT_TYPE_ARB:
> +      if (!ctx->Extensions.ARB_geometry_shader4)
> +         break;
>         *params = shProg->Geom.InputType;
> -      break;
> +      return;
>      case GL_GEOMETRY_OUTPUT_TYPE_ARB:
> +      if (!ctx->Extensions.ARB_geometry_shader4)
> +         break;
>         *params = shProg->Geom.OutputType;
> -      break;
> +      return;
>   #endif
>      case GL_ACTIVE_UNIFORM_BLOCK_MAX_NAME_LENGTH: {
>         unsigned i;
>         GLint max_len = 0;
>
> -      if (!ctx->Extensions.ARB_uniform_buffer_object) {
> -         _mesa_error(ctx, GL_INVALID_ENUM, "glGetProgramiv(pname)");
> -         return;
> -      }
> +      if (!ctx->Extensions.ARB_uniform_buffer_object)
> +         break;
>
>         for (i = 0; i<  shProg->NumUniformBlocks; i++) {
>   	 /* Add one for the terminating NUL character.
> @@ -563,20 +570,19 @@ get_programiv(struct gl_context *ctx, GLuint program, GLenum pname, GLint *param
>         }
>
>         *params = max_len;
> -      break;
> +      return;
>      }
>      case GL_ACTIVE_UNIFORM_BLOCKS:
> -      if (!ctx->Extensions.ARB_uniform_buffer_object) {
> -         _mesa_error(ctx, GL_INVALID_ENUM, "glGetProgramiv(pname)");
> -         return;
> -      }
> +      if (!ctx->Extensions.ARB_uniform_buffer_object)
> +         break;
>
>         *params = shProg->NumUniformBlocks;
> -      break;
> -   default:
> -      _mesa_error(ctx, GL_INVALID_ENUM, "glGetProgramiv(pname)");
>         return;
> +   default:
> +      break;
>      }
> +
> +   _mesa_error(ctx, GL_INVALID_ENUM, "glGetProgramiv(pname)");

I'm trying to get into the habit of including the bad enum value in 
error strings like this.  Inevitably, where I don't do this I 
eventually have to go in with gdb to get more info.  And this will 
probably be more useful with the ARB_debug extensions.

For your copy & paste convenience:

    _mesa_error(ctx, GL_INVALID_ENUM, "glGetProgramiv(pname=%s)",
                _mesa_lookup_enum_by_nr(pname));


Otherwise,
Reviewed-by: Brian Paul <brianp at vmware.com>

-Brian