prelink: Enable image wide prelinking

Add the ability to specify user level classes via the local.conf.

Use this new capability to add an image-prelink class that does an
image wide cross-prelink activity.

Signed-off-by: Mark Hatle <mhatle@windriver.com>

meta/classes/image-prelink.bbclass

@@ -0,0 +1,38 @@
+do_rootfs[depends] += "prelink-native:do_populate_sysroot"
+
+IMAGE_PREPROCESS_COMMAND += "prelink_image; "
+
+prelink_image () {
+#	export PSEUDO_DEBUG=4
+#	/bin/env | /bin/grep PSEUDO
+#	echo "LD_LIBRARY_PATH=$LD_LIBRARY_PATH"
+#	echo "LD_PRELOAD=$LD_PRELOAD"
+
+	pre_prelink_size=`du -ks ${IMAGE_ROOTFS} | awk '{size = $1 ; print size }'`
+	echo "Size before prelinking $pre_prelink_size."
+
+	# We need a prelink conf on the filesystem, add one if it's missing
+	if [ ! -e ${IMAGE_ROOTFS}/etc/prelink.conf ]; then
+		cp ${STAGING_DIR_NATIVE}/etc/prelink.conf \
+			${IMAGE_ROOTFS}/etc/prelink.conf
+		dummy_prelink_conf=true;
+	else
+		dummy_prelink_conf=false;
+	fi
+
+	# prelink!
+	${STAGING_DIR_NATIVE}/usr/sbin/prelink --root ${IMAGE_ROOTFS} -amR
+
+	# Remove the prelink.conf if we had to add it.
+	if [ $dummy_prelink_conf ]; then
+		rm -f ${IMAGE_ROOTFS}/etc/prelink.conf
+	fi
+
+	# Cleanup temporary file, it's not needed...
+	rm -f ${IMAGE_ROOTFS}/etc/prelink.cache
+
+	pre_prelink_size=`du -ks ${IMAGE_ROOTFS} | awk '{size = $1 ; print size }'`
+	echo "Size after prelinking $pre_prelink_size."
+}
+
+EXPORT_FUNCTIONS prelink_image