console: add and use qemu_display_find_default

Using the new display registry instead of #ifdefs in vl.c.
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>
Message-id: 20180301100547.18962-7-kraxel@redhat.com

include/ui/console.h

@@ -441,6 +441,7 @@ struct QemuDisplay {
 };
 
 void qemu_display_register(QemuDisplay *ui);
+bool qemu_display_find_default(DisplayOptions *opts);
 void qemu_display_early_init(DisplayOptions *opts);
 void qemu_display_init(DisplayState *ds, DisplayOptions *opts);
 

ui/console.c

@@ -2188,6 +2188,25 @@ void qemu_display_register(QemuDisplay *ui)
     dpys[ui->type] = ui;
 }
 
+bool qemu_display_find_default(DisplayOptions *opts)
+{
+    static DisplayType prio[] = {
+        DISPLAY_TYPE_GTK,
+        DISPLAY_TYPE_SDL,
+        DISPLAY_TYPE_COCOA
+    };
+    int i;
+
+    for (i = 0; i < ARRAY_SIZE(prio); i++) {
+        if (dpys[prio[i]] == NULL) {
+            continue;
+        }
+        opts->type = prio[i];
+        return true;
+    }
+    return false;
+}
+
 void qemu_display_early_init(DisplayOptions *opts)
 {
     assert(opts->type < DISPLAY_TYPE__MAX);

vl.c

@@ -4298,17 +4298,12 @@ int main(int argc, char **argv, char **envp)
     }
 #endif
     if (dpy.type == DISPLAY_TYPE_DEFAULT && !display_remote) {
-#if defined(CONFIG_GTK)
-        dpy.type = DISPLAY_TYPE_GTK;
-#elif defined(CONFIG_SDL)
-        dpy.type = DISPLAY_TYPE_SDL;
-#elif defined(CONFIG_COCOA)
-        dpy.type = DISPLAY_TYPE_COCOA;
-#elif defined(CONFIG_VNC)
-        vnc_parse("localhost:0,to=99,id=default", &error_abort);
-#else
-        dpy.type = DISPLAY_TYPE_NONE;
+        if (!qemu_display_find_default(&dpy)) {
+            dpy.type = DISPLAY_TYPE_NONE;
+#if defined(CONFIG_VNC)
+            vnc_parse("localhost:0,to=99,id=default", &error_abort);
 #endif
+        }
     }
     if (dpy.type == DISPLAY_TYPE_DEFAULT) {
         dpy.type = DISPLAY_TYPE_NONE;