fix a crasher in our EGL wrapper when attrib_list is NULL in eglChooseConfig

the EGL specification states that this should be treated as though it was
an empty list terminated with EGL_NONE.

Change-Id: I294104370a86b5e5c34c7bcf15c5459eab464631

2 files changed, 13 insertions, 6 deletions

diff --git a/opengl/libagl/egl.cpp b/opengl/libagl/egl.cpp
index b6e0aae..7cb01d0 100644
--- a/opengl/libagl/egl.cpp
+++ b/opengl/libagl/egl.cpp
@@ -1525,8 +1525,13 @@ EGLBoolean eglChooseConfig( EGLDisplay dpy, const EGLint *attrib_list,
     }
 
     if (ggl_unlikely(attrib_list==0)) {
-        *num_config = 0;
-        return EGL_TRUE;
+        /*
+         * A NULL attrib_list should be treated as though it was an empty
+         * one (terminated with EGL_NONE) as defined in
+         * section 3.4.1 "Querying Configurations" in the EGL specification.
+         */
+        static const EGLint dummy = EGL_NONE;
+        attrib_list = &dummy;
     }
 
     int numAttributes = 0;
diff --git a/opengl/libs/EGL/egl.cpp b/opengl/libs/EGL/egl.cpp
index e6cf792..ba09d08 100644
--- a/opengl/libs/EGL/egl.cpp
+++ b/opengl/libs/EGL/egl.cpp
@@ -843,10 +843,12 @@ EGLBoolean eglChooseConfig( EGLDisplay dpy, const EGLint *attrib_list,
     EGLint patch_index = -1;
     GLint attr;
     size_t size = 0;
-    while ((attr=attrib_list[size]) != EGL_NONE) {
-        if (attr == EGL_CONFIG_ID)
-            patch_index = size;
-        size += 2;
+    if (attrib_list) {
+        while ((attr=attrib_list[size]) != EGL_NONE) {
+            if (attr == EGL_CONFIG_ID)
+                patch_index = size;
+            size += 2;
+        }
     }
     if (patch_index >= 0) {
         size += 2; // we need copy the sentinel as well