From 06620ff364aef8ff26743f197d0fa26380991094 Mon Sep 17 00:00:00 2001
From: Ryan Houdek <Sonicadvance1@Gmail.com>
Date: Thu, 15 Aug 2013 18:07:03 +0000
Subject: [PATCH] [Android] Fall back to using dlsym on ourselves to pull in
 OpenGL Functions when eglGetProcAddress fails. This fixes an issue on the
 Chromebook where I was forced to link to libGLESv2 and pull in the functions
 statically since eglGetProcAddress wouldn't return any GLESv3 functions. This
 also changes glMapBuffer to glMapBufferOES because glMapBuffer isn't actually
 part of the OpenGL ES 3 spec...

---
 .../Plugins/Plugin_VideoOGL/Src/GLFunctions.cpp  | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/Source/Plugins/Plugin_VideoOGL/Src/GLFunctions.cpp b/Source/Plugins/Plugin_VideoOGL/Src/GLFunctions.cpp
index 2759fd82ff..e174a1e64d 100644
--- a/Source/Plugins/Plugin_VideoOGL/Src/GLFunctions.cpp
+++ b/Source/Plugins/Plugin_VideoOGL/Src/GLFunctions.cpp
@@ -3,6 +3,7 @@
 // Refer to the license.txt file included.
 #include "GLFunctions.h"
 #include "Log.h"
+#include <dlfcn.h>
 #ifdef USE_GLES3
 PFNGLMAPBUFFERPROC glMapBuffer;
 PFNGLMAPBUFFERRANGEPROC glMapBufferRange;
@@ -43,27 +44,35 @@ PFNGLGENQUERIESPROC glGenQueries;
 #endif
 namespace GLFunc
 {
+	void *self;
 	void LoadFunction(const char *name, void **func)
 	{
 #ifdef USE_GLES3
 		*func = (void*)eglGetProcAddress(name);
 		if (*func == NULL)
 		{
-			ERROR_LOG(VIDEO, "Couldn't load function %s", name);
-			exit(0);
+			// Fall back to trying dlsym
+			if (self) // Just in case dlopen fails
+				*func = dlsym(self, name);
+			if (*func == NULL)
+			{
+				ERROR_LOG(VIDEO, "Couldn't load function %s", name);
+				exit(0);
+			}
 		}
 #endif
 	}
 
 	void Init()
 	{
+		self = dlopen(NULL, RTLD_LAZY);
 		LoadFunction("glBeginQuery", (void**)&glBeginQuery);
 		LoadFunction("glEndQuery", (void**)&glEndQuery);
 		LoadFunction("glGetQueryObjectuiv", (void**)&glGetQueryObjectuiv);
 		LoadFunction("glDeleteQueries", (void**)&glDeleteQueries);
 		LoadFunction("glGenQueries", (void**)&glGenQueries);
 		{
-			LoadFunction("glMapBuffer", (void**)&glMapBuffer);	
+			LoadFunction("glMapBufferOES", (void**)&glMapBuffer);	
 			LoadFunction("glUnmapBuffer", (void**)&glUnmapBuffer);
 			LoadFunction("glMapBufferRange", (void**)&glMapBufferRange);
 			LoadFunction("glBindBufferRange", (void**)&glBindBufferRange);
@@ -93,5 +102,6 @@ namespace GLFunc
 
 		LoadFunction("glGetUniformBlockIndex", (void**)&glGetUniformBlockIndex);
 		LoadFunction("glUniformBlockBinding", (void**)&glUniformBlockBinding);
+		dlclose(self);
 	}
 }