[display] Refactor to avoid implicit framebuffer allocation.

platform/armemu/display.c

 /*
  * Copyright (c) 2010 Travis Geiselbrecht
  *
  * Permission is hereby granted, free of charge, to any person obtaining
  * a copy of this software and associated documentation files
  * (the "Software"), to deal in the Software without restriction,
  * including without limitation the rights to use, copy, modify, merge,
  * publish, distribute, sublicense, and/or sell copies of the Software,
  * and to permit persons to whom the Software is furnished to do so,
  * subject to the following conditions:
@@ skipping 35 matching lines @@
 
     display_fb = (void *)DISPLAY_FRAMEBUFFER;
     display_w = *REG32(DISPLAY_WIDTH);
     display_h = *REG32(DISPLAY_HEIGHT);
 
 #if DRAW_TEST_PATTERN
     gfx_draw_pattern();
 #endif
 }
 
+status_t display_get_framebuffer(struct display_framebuffer *fb)
+{

[gkalsi, 2016/03/09 21:13:37]

DEBUG_ASSERT(fb)

[cdotstout, 2016/03/09 22:48:00]

Done.

+    if (!has_display())
+        return ERR_NOT_FOUND;
+
+    fb->format = DISPLAY_FORMAT_RGB_x888;
+    fb->flush = NULL;
+    fb->image.format = IMAGE_FORMAT_RGB_x888;
+    fb->image.pixels = display_fb;
+    fb->image.width = display_w;
+    fb->image.height = display_h;
+    fb->image.rowbytes = display_w;
+
+    return NO_ERROR;
+}
+
 status_t display_get_info(struct display_info *info)
 {

[gkalsi, 2016/03/09 21:13:37]

DEBUG_ASSERT(info)

[cdotstout, 2016/03/09 22:48:00]

Done.

     if (!has_display())
         return ERR_NOT_FOUND;
 
-    info->framebuffer = display_fb;
-    info->format = GFX_FORMAT_RGB_x888;
+    info->format = DISPLAY_FORMAT_RGB_x888;
     info->width = display_w;
     info->height = display_h;
-    info->stride = display_w;
-    info->flush = NULL;
 
     return NO_ERROR;
 }