From 68ecbc34f1cb29dfda116724c87d602eba961eb2 Mon Sep 17 00:00:00 2001
From: reimar <reimar@b3059339-0415-0410-9bf9-f77b7e298cf2>
Date: Sun, 13 Nov 2005 21:53:26 +0000
Subject: [PATCH] disable *SwapInterval function when extensions are missing,
 since it can cause crashes.

git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@16985 b3059339-0415-0410-9bf9-f77b7e298cf2
---
 libvo/gl_common.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/libvo/gl_common.c b/libvo/gl_common.c
index d6a3a153ad..f23d0728e6 100644
--- a/libvo/gl_common.c
+++ b/libvo/gl_common.c
@@ -251,6 +251,7 @@ static void *setNull(const GLubyte *s) {
  * \param getProcAddress function to resolve function names, may be NULL
  */
 static void getFunctions(void *(*getProcAddress)(const GLubyte *)) {
+  const char *extensions = glGetString(GL_EXTENSIONS);
   if (!getProcAddress)
     getProcAddress = setNull;
   GenBuffers = getProcAddress("glGenBuffers");
@@ -323,6 +324,9 @@ static void getFunctions(void *(*getProcAddress)(const GLubyte *)) {
     ProgramEnvParameter4f = getProcAddress("glProgramEnvParameter4fARB");
   if (!ProgramEnvParameter4f)
     ProgramEnvParameter4f = getProcAddress("glProgramEnvParameter4fNV");
+  if (!extensions || !strstr(extensions, "_swap_control"))
+    SwapInterval = NULL;
+  else {
   SwapInterval = getProcAddress("glXSwapInterval");
   if (!SwapInterval)
     SwapInterval = getProcAddress("glXSwapIntervalEXT");
@@ -334,6 +338,7 @@ static void getFunctions(void *(*getProcAddress)(const GLubyte *)) {
     SwapInterval = getProcAddress("wglSwapIntervalEXT");
   if (!SwapInterval)
     SwapInterval = getProcAddress("wglSwapIntervalSGI");
+  }
 }
 
 /**