From 771d75e722abc2b18799f734801c2b88d88a19e7 Mon Sep 17 00:00:00 2001
From: Nigel Stewart <nigels@users.sourceforge.net>
Date: Sat, 10 Oct 2015 09:26:00 +1000
Subject: [PATCH] More refinements for OSMesa support - still not working

---
 .travis.yml                |  2 +-
 auto/Makefile              |  3 +--
 auto/src/glew_head.c       |  6 +++---
 auto/src/glew_init_tail.c  |  4 ++--
 auto/src/glew_str_wgl.c    |  3 +--
 auto/src/glewinfo_head.c   |  5 ++---
 auto/src/glewinfo_wgl.c    |  3 +--
 build/cmake/CMakeLists.txt | 15 +++++++++++++++
 8 files changed, 26 insertions(+), 15 deletions(-)

diff --git a/.travis.yml b/.travis.yml
index 59b0d7f..c091bb4 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,7 +1,7 @@
 language: cpp
 #sudo: false
 install:
-- sudo apt-get install git dos2unix
+- sudo apt-get install git dos2unix libosmesa-dev
 script:
 - make -C auto clobber
 - make extensions
diff --git a/auto/Makefile b/auto/Makefile
index af66a8e..a384bd6 100644
--- a/auto/Makefile
+++ b/auto/Makefile
@@ -204,8 +204,7 @@ $(S.DEST)/glew.c: $(EXT)/.dummy
 	$(BIN)/make_list.pl $(GL_CORE_SPEC) | grep -v '\"GL_VERSION' >> $@
 	$(BIN)/make_list.pl $(GL_EXT_SPEC) >> $@
 	echo -e "\n  return GLEW_OK;\n}\n" >> $@
-	echo -e "\n#if defined(GLEW_OSMESA)" >> $@
-	echo -e "\n#elif defined(_WIN32)" >> $@
+	echo -e "\n#if defined(_WIN32) && ! defined(GLEW_OSMESA)" >> $@
 	echo -e "\n#if !defined(GLEW_MX)" >> $@
 	$(BIN)/make_def_fun.pl WGL $(WGL_EXT_SPEC) >> $@
 	$(BIN)/make_def_var.pl WGL $(WGL_EXT_SPEC) >> $@
diff --git a/auto/src/glew_head.c b/auto/src/glew_head.c
index fd9c0d3..1b4ed77 100644
--- a/auto/src/glew_head.c
+++ b/auto/src/glew_head.c
@@ -140,10 +140,10 @@ void* NSGLGetProcAddress (const GLubyte *name)
 /*
  * Define glewGetProcAddress.
  */
-#if defined(GLEW_OSMESA)
+#if defined(GLEW_REGAL)
+#  define glewGetProcAddress(name) regalGetProcAddress((const GLchar *)name)
+#elif defined(GLEW_OSMESA)
 #  define glewGetProcAddress(name) OSMesaGetProcAddress((const char *)name)
-#elif defined(GLEW_REGAL)
-#  define glewGetProcAddress(name) regalGetProcAddress((const GLchar *) name)
 #elif defined(_WIN32)
 #  define glewGetProcAddress(name) wglGetProcAddress((LPCSTR)name)
 #elif defined(__APPLE__) && !defined(GLEW_APPLE_GLX)
diff --git a/auto/src/glew_init_tail.c b/auto/src/glew_init_tail.c
index f0e2573..ba68ccf 100644
--- a/auto/src/glew_init_tail.c
+++ b/auto/src/glew_init_tail.c
@@ -39,11 +39,11 @@ GLenum GLEWAPIENTRY glewInit (void)
   GLenum r;
   r = glewContextInit();
   if ( r != 0 ) return r;
-#if defined(GLEW_OSMESA)
+#if defined(GLEW_OSMESA) || defined(__ANDROID__) || defined(__native_client__) || defined(__HAIKU__)
   return r;
 #elif defined(_WIN32)
   return wglewInit();
-#elif !defined(__ANDROID__) && !defined(__native_client__) && !defined(__HAIKU__) && (!defined(__APPLE__) || defined(GLEW_APPLE_GLX)) /* _UNIX */
+#elif !defined(__APPLE__) || defined(GLEW_APPLE_GLX) /* _UNIX */
   return glxewInit();
 #else
   return r;
diff --git a/auto/src/glew_str_wgl.c b/auto/src/glew_str_wgl.c
index 4fd37fd..01055a4 100644
--- a/auto/src/glew_str_wgl.c
+++ b/auto/src/glew_str_wgl.c
@@ -4,8 +4,7 @@
   return ret;
 }
 
-#if defined(GLEW_OSMESA)
-#elif defined(_WIN32)
+#if defined(_WIN32) && !defined(GLEW_OSMESA)
 
 #if defined(GLEW_MX)
 GLboolean GLEWAPIENTRY wglewContextIsSupported (const WGLEWContext* ctx, const char* name)
diff --git a/auto/src/glewinfo_head.c b/auto/src/glewinfo_head.c
index 96108e8..fd4bead 100644
--- a/auto/src/glewinfo_head.c
+++ b/auto/src/glewinfo_head.c
@@ -24,11 +24,10 @@ static FILE* f;
 #ifdef GLEW_MX
 GLEWContext _glewctx;
 #define glewGetContext() (&_glewctx)
-#if defined(GLEW_OSMESA)
-#elif defined(_WIN32)
+#if defined(_WIN32)
 WGLEWContext _wglewctx;
 #define wglewGetContext() (&_wglewctx)
-#elif !defined(__APPLE__) && !defined(__HAIKU__) || defined(GLEW_APPLE_GLX)
+#elif !defined(GLEW_OSMESA) && !defined(__APPLE__) && !defined(__HAIKU__) || defined(GLEW_APPLE_GLX)
 GLXEWContext _glxewctx;
 #define glxewGetContext() (&_glxewctx)
 #endif
diff --git a/auto/src/glewinfo_wgl.c b/auto/src/glewinfo_wgl.c
index b2c2242..c80264e 100644
--- a/auto/src/glewinfo_wgl.c
+++ b/auto/src/glewinfo_wgl.c
@@ -2,8 +2,7 @@
 
 /* ------------------------------------------------------------------------ */
 
-#if defined(GLEW_OSMESA)
-#elif defined(_WIN32)
+#if defined(_WIN32) && !defined(GLEW_OSMESA)
 
 static void wglewInfo ()
 {
diff --git a/build/cmake/CMakeLists.txt b/build/cmake/CMakeLists.txt
index 1563f9f..425fffb 100644
--- a/build/cmake/CMakeLists.txt
+++ b/build/cmake/CMakeLists.txt
@@ -13,6 +13,7 @@ endif()
 set(CMAKE_DEBUG_POSTFIX d)
 
 option (BUILD_UTILS "utilities" ON)
+option (GLEW_OSMESA "OSMesa mode" FALSE)
 
 set (GLEW_DIR ${CMAKE_CURRENT_SOURCE_DIR}/../..)
 
@@ -41,6 +42,20 @@ set (GLEW_LIBRARIES ${OPENGL_LIBRARIES})
 
 add_definitions (-DGLEW_NO_GLU)
 
+#### OSMesa ####
+
+if (GLEW_OSMESA)
+  if (WIN32)
+    set (OSMESA_LIB_NAME osmesa)
+  else ()
+    set (OSMESA_LIB_NAME OSMesa)
+  endif ()
+  add_definitions (-DGLEW_OSMESA)
+  set (GLEW_LIBRARIES ${OSMESA_LIB_NAME} ${OPENGL_LIBRARIES})
+endif ()
+
+#### GLEW ####
+
 include_directories (${GLEW_DIR}/include)
 
 add_library (glew SHARED ${GLEW_DIR}/src/glew.c)