Refactor version file generation

CMakeLists.txt

@@ -30,8 +30,17 @@ set(
     GL/texture.c
     GL/util.c
     GL/yalloc/yalloc.c
+    ${CMAKE_CURRENT_BINARY_DIR}/version.c
 )
 
+execute_process(
+    COMMAND git describe --abbrev=4 --dirty --always --tags
+    OUTPUT_VARIABLE GLDC_VERSION
+    OUTPUT_STRIP_TRAILING_WHITESPACE
+)
+
+configure_file(GL/version.c.in ${CMAKE_CURRENT_BINARY_DIR}/version.c)
+
 if(PLATFORM_DREAMCAST)
     set(SOURCES ${SOURCES} GL/platforms/sh4.c)
 else()

GL/version.c.in

@@ -0,0 +1,2 @@
+
+const char* GLDC_VERSION = "@GLDC_VERSION@";

include/GL/glkos.h

@@ -4,6 +4,9 @@
 
 __BEGIN_DECLS
 
+extern const char* GLDC_VERSION;
+
+
 /*
  * Dreamcast specific compressed + twiddled formats.
  * We use constants from the range 0xEEE0 onwards