mesa: fix glGetActiveUniformsiv regression

Commit 7519ddb caused regression to glGetActiveUniformsiv.
Patch adds back validation loop of all given uniforms before
writing any values, not touching params in case of errors
is tested by the conformance suite.

Signed-off-by: Tapani Pälli <tapani.palli@intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=90149
Reviewed-by: Martin Peres <martin.peres@linux.intel.com>

src/mesa/main/uniform_query.cpp

@@ -129,14 +129,26 @@ _mesa_GetActiveUniformsiv(GLuint program,
 
    res_prop = resource_prop_from_uniform_prop(pname);
 
+   /* We need to first verify that each entry exists as active uniform. If
+    * not, generate error and do not cause any other side effects.
+    *
+    * In the case of and error condition, Page 16 (section 2.3.1 Errors)
+    * of the OpenGL 4.5 spec says:
+    *
+    *     "If the generating command modifies values through a pointer argu-
+    *     ment, no change is made to these values."
+    */
+   for (int i = 0; i < uniformCount; i++) {
+      if (!_mesa_program_resource_find_index(shProg, GL_UNIFORM,
+                                              uniformIndices[i])) {
+         _mesa_error(ctx, GL_INVALID_VALUE, "glGetActiveUniformsiv(index)");
+         return;
+      }
+   }
+
    for (int i = 0; i < uniformCount; i++) {
       res = _mesa_program_resource_find_index(shProg, GL_UNIFORM,
                                               uniformIndices[i]);
-      if (!res) {
-         _mesa_error(ctx, GL_INVALID_VALUE, "glGetActiveUniformsiv(index)");
-         break;
-      }
-
       if (!_mesa_program_resource_prop(shProg, res, uniformIndices[i],
                                        res_prop, &params[i],
                                        "glGetActiveUniformsiv"))