[Mesa-dev] [PATCH] shaderapi: Fix AttachShader error

[Tapani Pälli]

From: bma <Bo.Ma at windriver.com>

Detect a duplicate Shader type as and error instead of silently allowing
it, restrict to ES2 API.

v2: Tapani Pälli <tapani.palli at intel.com>
    - make the check run time instead of compile time

Signed-off-by: bma <Bo.Ma at windriver.com>
Signed-off-by: Tapani Pälli <tapani.palli at intel.com>
---
 src/mesa/main/shaderapi.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/src/mesa/main/shaderapi.c b/src/mesa/main/shaderapi.c
index 2590abe..39f557a 100644
--- a/src/mesa/main/shaderapi.c
+++ b/src/mesa/main/shaderapi.c
@@ -207,6 +207,9 @@ attach_shader(struct gl_context *ctx, GLuint program, GLuint shader)
    struct gl_shader *sh;
    GLuint i, n;
 
+   const bool same_type_disallowed =
+	_mesa_is_gles(ctx) || _mesa_is_gles3(ctx);
+
    shProg = _mesa_lookup_shader_program_err(ctx, program, "glAttachShader");
    if (!shProg)
       return;
@@ -218,12 +221,20 @@ attach_shader(struct gl_context *ctx, GLuint program, GLuint shader)
 
    n = shProg->NumShaders;
    for (i = 0; i < n; i++) {
-      if (shProg->Shaders[i] == sh) {
+      if (shProg->Shaders[i] == sh ||
+         same_type_disallowed && shProg->Shaders[i]->Type == sh->Type) {
+
          /* The shader is already attched to this program.  The
           * GL_ARB_shader_objects spec says:
           *
           *     "The error INVALID_OPERATION is generated by AttachObjectARB
           *     if <obj> is already attached to <containerObj>."
+          *
+          * Shader with the same type is already attached to this program,
+          * OpenGL ES 2.0 and 3.0 spec says:
+          *
+          *     "Multiple shader objects of the same type may not be attached
+          *     to a single program object."
           */
          _mesa_error(ctx, GL_INVALID_OPERATION, "glAttachShader");
          return;
-- 
1.8.1