commit 2be54a8e8ccb206eeedd319cf48a3c81797b83a4
author Brian Paul <brian.paul@tungstengraphics.com> Tue Jul 08 16:17:04 2008 -0600
committer Brian Paul <brian.paul@tungstengraphics.com> Tue Jul 08 16:17:04 2008 -0600
tree b0066cf6c5be269e0e158ddef15097a2822fdb39
parent 44029f15a8c841d0deb3c7b477bc36ca7a9cd3e6

mesa: implement glGetUniformiv() with new ctx->Driver function

The old implementation could overwrite the caller's param buffer.

src/mesa/shader/shader_api.c

diff --git a/src/mesa/shader/shader_api.c b/src/mesa/shader/shader_api.c
index 6cfdf57..105f76b 100644
--- a/src/mesa/shader/shader_api.c
+++ b/src/mesa/shader/shader_api.c
@@ -955,12 +955,15 @@
 }
 
 
+#define MAX_UNIFORM_ELEMENTS 16
+
 /**
- * Called via ctx->Driver.GetUniformfv().
+ * Helper for GetUniformfv(), GetUniformiv()
+ * Returns number of elements written to 'params' output.
  */
-static void
-_mesa_get_uniformfv(GLcontext *ctx, GLuint program, GLint location,
-                    GLfloat *params)
+static GLuint
+get_uniformfv(GLcontext *ctx, GLuint program, GLint location,
+              GLfloat *params)
 {
    struct gl_shader_program *shProg
       = _mesa_lookup_shader_program(ctx, program);
@@ -984,9 +987,13 @@
 
          ASSERT(prog);
          if (prog) {
+            /* See uniformiv() below */                    
+            assert(prog->Parameters->Parameters[progPos].Size <= MAX_UNIFORM_ELEMENTS);
+
             for (i = 0; i < prog->Parameters->Parameters[progPos].Size; i++) {
                params[i] = prog->Parameters->ParameterValues[progPos][i];
             }
+            return prog->Parameters->Parameters[progPos].Size;
          }
       }
       else {
@@ -996,6 +1003,35 @@
    else {
       _mesa_error(ctx, GL_INVALID_OPERATION, "glGetUniformfv(program)");
    }
+   return 0;
+}
+
+
+/**
+ * Called via ctx->Driver.GetUniformfv().
+ */
+static void
+_mesa_get_uniformfv(GLcontext *ctx, GLuint program, GLint location,
+                    GLfloat *params)
+{
+   (void) get_uniformfv(ctx, program, location, params);
+}
+
+
+/**
+ * Called via ctx->Driver.GetUniformiv().
+ */
+static void
+_mesa_get_uniformiv(GLcontext *ctx, GLuint program, GLint location,
+                    GLint *params)
+{
+   GLfloat fparams[MAX_UNIFORM_ELEMENTS];
+   GLuint n = get_uniformfv(ctx, program, location, fparams);
+   GLuint i;
+   assert(n <= MAX_UNIFORM_ELEMENTS);
+   for (i = 0; i < n; i++) {
+      params[i] = (GLint) fparams[i];
+   }
 }
 
 
@@ -1413,6 +1449,7 @@
    driver->GetShaderInfoLog = _mesa_get_shader_info_log;
    driver->GetShaderSource = _mesa_get_shader_source;
    driver->GetUniformfv = _mesa_get_uniformfv;
+   driver->GetUniformiv = _mesa_get_uniformiv;
    driver->GetUniformLocation = _mesa_get_uniform_location;
    driver->IsProgram = _mesa_is_program;
    driver->IsShader = _mesa_is_shader;