[OE-core] [PATCH] qemu/local.conf.sample: Add sdl PACKAGECONFIG

[Richard Purdie]

Currently the SDL configuration option for qemu floats. This is confusing to new users
and makes the build non-determinstic. This patch adds a PACKAGECONFIG option, defaulting
to off and adds documentation to local.conf.sample leaving it on by default since this
is the configuration our quick start assumes.

Signed-off-by: Richard Purdie <richard.purdie at linuxfoundation.org>
---
diff --git a/meta/conf/local.conf.sample b/meta/conf/local.conf.sample
index 885d4db..061524a 100644
--- a/meta/conf/local.conf.sample
+++ b/meta/conf/local.conf.sample
@@ -229,6 +229,17 @@ BB_DISKMON_DIRS = "\
 #file://.* http://someserver.tld/share/sstate/PATH;downloadfilename=PATH \n \
 #file://.* file:///some/local/dir/sstate/PATH"
 
+
+#
+# Qemu configuration
+#
+# By default qemu will build with a builtin VNC server where graphical output can be
+# seen. The two lines below enable the SDL backend too. This assumes there is a
+# libsdl library available on your build system.
+PACKAGECONFIG_pn-qemu-native = "sdl"
+ASSUME_PROVIDED += "libsdl-native"
+
+
 # CONF_VERSION is increased each time build/conf/ changes incompatibly and is used to
 # track the version of this file when it was generated. This can safely be ignored if
 # this doesn't mean anything to you.
diff --git a/meta/recipes-devtools/qemu/qemu.inc b/meta/recipes-devtools/qemu/qemu.inc
index 319dcde..740d571 100644
--- a/meta/recipes-devtools/qemu/qemu.inc
+++ b/meta/recipes-devtools/qemu/qemu.inc
@@ -93,6 +93,7 @@ PACKAGECONFIG[uuid] = "--enable-uuid,--disable-uuid,util-linux,"
 PACKAGECONFIG[curses] = "--enable-curses,--disable-curses,ncurses,"
 PACKAGECONFIG[gtk+] = "--enable-gtk,--disable-gtk,gtk+ libvte,"
 PACKAGECONFIG[libcap-ng] = "--enable-cap-ng,--disable-cap-ng,libcap-ng,"
+PACKAGECONFIF[sdl] = "--enable-sdl,--disable-sdl,libsdl,"
 
 # Qemu target will not build in world build for ARM or Mips
 BROKEN_qemuarm = "1"