qapi: Parameter gl of DisplayType now accept an enum

v2: Rebase on top of master
v3: Fix the json format (Eric Blake)
    Fix a comparison issue (Gerd Hoffmann)
Signed-off-by: NElie Tournier <elie.tournier@collabora.com>
Message-id: 20180413135842.21325-2-tournier.elie@gmail.com
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>

qapi/ui.json

@@ -1019,6 +1019,24 @@
 { 'struct'  : 'DisplayGTK',
   'data'    : { '*grab-on-hover' : 'bool' } }
 
+ ##
+ # @DisplayGLMode:
+ #
+ # Display OpenGL mode.
+ #
+ # @off: Disable OpenGL (default).
+ # @on: Use OpenGL, pick context type automatically.
+ #      Would better be named 'auto' but is called 'on' for backward
+ #      compatibility with bool type.
+ # @core: Use OpenGL with Core (desktop) Context.
+ # @es: Use OpenGL with ES (embedded systems) Context.
+ #
+ # Since: 2.13
+ #
+ ##
+ { 'enum'    : 'DisplayGLMode',
+   'data'    : [ 'off', 'on', 'core', 'es' ] }
+
 ##
 # @DisplayType:
 #
@@ -1048,7 +1066,7 @@
   'base'    : { 'type'           : 'DisplayType',
                 '*full-screen'   : 'bool',
                 '*window-close'  : 'bool',
-                '*gl'            : 'bool' },
+                '*gl'            : 'DisplayGLMode' },
   'discriminator' : 'type',
   'data'    : { 'default'        : 'DisplayNoOpts',
                 'none'           : 'DisplayNoOpts',

vl.c

@@ -2143,9 +2143,9 @@ static void parse_display(const char *p)
                 opts = nextopt;
                 dpy.has_gl = true;
                 if (strstart(opts, "on", &nextopt)) {
-                    dpy.gl = true;
+                    dpy.gl = DISPLAYGL_MODE_ON;
                 } else if (strstart(opts, "off", &nextopt)) {
-                    dpy.gl = false;
+                    dpy.gl = DISPLAYGL_MODE_OFF;
                 } else {
                     goto invalid_sdl_args;
                 }
@@ -2186,9 +2186,9 @@ static void parse_display(const char *p)
                 opts = nextopt;
                 dpy.has_gl = true;
                 if (strstart(opts, "on", &nextopt)) {
-                    dpy.gl = true;
+                    dpy.gl = DISPLAYGL_MODE_ON;
                 } else if (strstart(opts, "off", &nextopt)) {
-                    dpy.gl = false;
+                    dpy.gl = DISPLAYGL_MODE_OFF;
                 } else {
                     goto invalid_gtk_args;
                 }
@@ -4356,7 +4356,7 @@ int main(int argc, char **argv, char **envp)
     qemu_display_early_init(&dpy);
     qemu_console_early_init();
 
-    if (dpy.has_gl && dpy.gl && display_opengl == 0) {
+    if (dpy.has_gl && dpy.gl != DISPLAYGL_MODE_OFF && display_opengl == 0) {
 #if defined(CONFIG_OPENGL)
         error_report("OpenGL is not supported by the display");
 #else