Mesa (master): getteximage: avoid to lookup textures with id 0

[Samuel Pitoiset]

Module: Mesa
Branch: master
Commit: 5ae54c0cf7acfb792d2ca9b22cd5fb5ba811d32c
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=5ae54c0cf7acfb792d2ca9b22cd5fb5ba811d32c

Author: Samuel Pitoiset <samuel.pitoiset at gmail.com>
Date:   Wed Mar  1 22:54:09 2017 +0100

getteximage: avoid to lookup textures with id 0

This fixes the following assertion when the key is 0.

main/hash.c:181: _mesa_HashLookup_unlocked: Assertion `key' failed.

Fixes: 633c959fae ("getteximage: Return correct error value when texure object is not found")
Signed-off-by: Samuel Pitoiset <samuel.pitoiset at gmail.com>
Reviewed-by: Marek Olšák <marek.olsak at amd.com>

---

 src/mesa/main/texgetimage.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/src/mesa/main/texgetimage.c b/src/mesa/main/texgetimage.c
index c0c50b0..37fda3d 100644
--- a/src/mesa/main/texgetimage.c
+++ b/src/mesa/main/texgetimage.c
@@ -1458,7 +1458,9 @@ _mesa_GetTextureSubImage(GLuint texture, GLint level,
 {
    GET_CURRENT_CONTEXT(ctx);
    static const char *caller = "glGetTextureSubImage";
-   struct gl_texture_object *texObj =
+   struct gl_texture_object *texObj = NULL;
+
+   if (texture > 0)
       _mesa_lookup_texture(ctx, texture);
 
    if (!texObj) {
@@ -1774,9 +1776,11 @@ _mesa_GetCompressedTextureSubImage(GLuint texture, GLint level,
 {
    GET_CURRENT_CONTEXT(ctx);
    static const char *caller = "glGetCompressedTextureImage";
-   struct gl_texture_object *texObj;
+   struct gl_texture_object *texObj = NULL;
+
+   if (texture > 0)
+      texObj = _mesa_lookup_texture(ctx, texture);
 
-   texObj = _mesa_lookup_texture(ctx, texture);
    if (!texObj) {
       _mesa_error(ctx, GL_INVALID_VALUE, "%s(texture)", caller);
       return;