[Piglit] [PATCH] shader_runner: fix uniform array name lookups

[Arthur Huillet]

From: Arthur Huillet <ahuillet at nvidia.com>

Don't look up uniform names for non-zero array elements, as this is illegal per GL4.5.

>From the discussion of GetProgramResourceIndex in the GL4.5 spec:

       If name exactly matches the name string of one of the active resources for
    programInterface, the index of the matched resource is returned. Additionally, if
    name would exactly match the name string of an active resource if "[0]" were
    appended to name, the index of the matched resource is returned. Otherwise, name
    is considered not to be the name of an active resource, and INVALID_INDEX is
    returned. Note that if an interface enumerates a single active resource list entry for
    an array variable (e.g., "a[0]"), a name identifying any array element other than
    the first (e.g., "a[1]") is not considered to match.

Instead, strip the "[xxx]" part of the name for the lookup.

The NVIDIA proprietary driver enforces this rule of the specification, while Mesa
is more permissive. Piglit shouldn't rely on the implementation being lax.

Signed-off-by: Arthur Huillet <ahuillet at nvidia.com>
---
 tests/shaders/shader_runner.c | 33 ++++++++++++++++++++++++++-------
 1 file changed, 26 insertions(+), 7 deletions(-)

diff --git a/tests/shaders/shader_runner.c b/tests/shaders/shader_runner.c
index c193de9..22a9828 100644
--- a/tests/shaders/shader_runner.c
+++ b/tests/shaders/shader_runner.c
@@ -1227,11 +1227,12 @@ check_double_support(void)
  * the data.  If the uniform is not in a uniform block, returns false.
  */
 bool
-set_ubo_uniform(const char *name, const char *type, const char *line, int ubo_array_index)
+set_ubo_uniform(char *name, const char *type, const char *line, int ubo_array_index)
 {
 	GLuint uniform_index;
 	GLint block_index;
 	GLint offset;
+	GLint array_index;
 	char *data;
 	float f[16];
 	double d[16];
@@ -1242,7 +1243,29 @@ set_ubo_uniform(const char *name, const char *type, const char *line, int ubo_ar
 	if (!num_uniform_blocks)
 		return false;
 
-	glGetUniformIndices(prog, 1, &name, &uniform_index);
+	/* if the uniform is an array, strip the index, as GL
+	   prevents non-zero indexes from matching a name */
+	if (name[name_len - 1] == ']') {
+		int i;
+
+		for (i = name_len - 1; (i > 0) && isdigit(name[i-1]); --i)
+			/* empty */;
+
+		array_index = strtol(&name[i], NULL, 0);
+
+		if (i) {
+			i--;
+			if (name[i] != '[') {
+				printf("cannot parse uniform \"%s\"\n", name);
+				piglit_report_result(PIGLIT_FAIL);
+			}
+			name[i] = 0;
+		}
+
+	}
+
+
+	glGetUniformIndices(prog, 1, (const char **)&name, &uniform_index);
 	if (uniform_index == GL_INVALID_INDEX) {
 		printf("cannot get index of uniform \"%s\"\n", name);
 		piglit_report_result(PIGLIT_FAIL);
@@ -1265,14 +1288,10 @@ set_ubo_uniform(const char *name, const char *type, const char *line, int ubo_ar
 
 	if (name[name_len - 1] == ']') {
 		GLint stride;
-		int i;
-
-		for (i = name_len - 1; (i > 0) && isdigit(name[i-1]); --i)
-			/* empty */;
 
 		glGetActiveUniformsiv(prog, 1, &uniform_index,
 				      GL_UNIFORM_ARRAY_STRIDE, &stride);
-		offset += stride * strtol(&name[i], NULL, 0);
+		offset += stride * array_index;
 	}
 
 	glBindBuffer(GL_UNIFORM_BUFFER,
-- 
2.3.0