mesa: Fix ACTIVE_*_MAX_LENGTH program queries (ARB_gl_spirv)

Since ARB_gl_spirv it is possible to miss a lot of name reflection
information, so it is needed to add NULL name checks for several
queries, and return a specific value on those cases. This commit add
them for ACTIVE_UNIFORM_BLOCK_MAX_NAME_LENGTH,
ACTIVE_ATTRIBUTE_MAX_LENGTH and ACTIVE_UNIFORM_MAX_LENGTH.

From ARB_gl_spirv spec:

   "If pname is ACTIVE_UNIFORM_BLOCK_MAX_NAME_LENGTH, the length of
    the longest active uniform block name, including the null
    terminator, is returned. If no active uniform blocks exist, zero
    is returned. If no name reflection information is available, one
    is returned.

    If pname is ACTIVE_ATTRIBUTE_MAX_LENGTH, the length of the longest
    active attribute name, including a null terminator, is returned.
    If no active attributes exist, zero is returned. If no name
    reflection information is available, one is returned.

    If pname is ACTIVE_UNIFORM_MAX_LENGTH, the length of the longest
    active uniform name, including a null terminator, is returned. If
    no active uniforms exist, zero is returned. If no name reflection
    information is available, one is returned."

Reviewed-by: Caio Marcelo de Oliveira Filho <[email protected]>

1 files changed, 12 insertions, 3 deletions

diff --git a/src/mesa/main/shader_query.cpp b/src/mesa/main/shader_query.cpp
index d3549535ea0..3fcd4fcedc5 100644
--- a/src/mesa/main/shader_query.cpp
+++ b/src/mesa/main/shader_query.cpp
@@ -244,9 +244,18 @@ _mesa_longest_attribute_name_length(struct gl_shader_program *shProg)
       if (res->Type == GL_PROGRAM_INPUT &&
           res->StageReferences & (1 << MESA_SHADER_VERTEX)) {
 
-          const size_t length = strlen(RESOURCE_VAR(res)->name);
-          if (length >= longest)
-             longest = length + 1;
+         /* From the ARB_gl_spirv spec:
+          *
+          *   "If pname is ACTIVE_ATTRIBUTE_MAX_LENGTH, the length of the
+          *    longest active attribute name, including a null terminator, is
+          *    returned.  If no active attributes exist, zero is returned. If
+          *    no name reflection information is available, one is returned."
+          */
+         const size_t length = RESOURCE_VAR(res)->name != NULL ?
+            strlen(RESOURCE_VAR(res)->name) : 0;
+
+         if (length >= longest)
+            longest = length + 1;
       }
    }