[Feature][YUKUAI_patch]add 18.02 code
Only Configure: No
Affected branch: master
Affected module: unknow
Is it affected on both ZXIC and MTK: only ZXIC
Self-test: Yes
Doc Update: No
Change-Id: I7f71153004f10fc0ea5adfa083866aaeeb1053ac
diff --git a/rootfs/sbin/mount-copybind b/rootfs/sbin/mount-copybind
new file mode 100755
index 0000000..e32e675
--- /dev/null
+++ b/rootfs/sbin/mount-copybind
@@ -0,0 +1,56 @@
+#!/bin/sh
+#
+# Perform a bind mount, copying existing files as we do so to ensure the
+# overlaid path has the necessary content.
+
+if [ $# -lt 2 ]; then
+ echo >&2 "Usage: $0 spec mountpoint [OPTIONS]"
+ exit 1
+fi
+
+# e.g. /var/volatile/lib
+spec=$1
+
+# e.g. /var/lib
+mountpoint=$2
+
+if [ $# -gt 2 ]; then
+ options=$3
+else
+ options=
+fi
+
+[ -n "$options" ] && options=",$options"
+
+mkdir -p "${spec%/*}"
+
+if [ -d "$mountpoint" ]; then
+
+ if [ -d "$spec" ]; then
+ specdir_existed=yes
+ else
+ specdir_existed=no
+ mkdir "$spec"
+ fi
+
+ # Fast version of calculating `dirname ${spec}`/.`basename ${spec}`-work
+ overlay_workdir="${spec%/*}/.${spec##*/}-work"
+ mkdir "${overlay_workdir}"
+
+ # Try to mount using overlay, which is must faster than copying files.
+ # If that fails, fall back to slower copy.
+ if ! mount -t overlay overlay -olowerdir="$mountpoint",upperdir="$spec",workdir="$overlay_workdir" "$mountpoint" > /dev/null 2>&1; then
+
+ if [ "$specdir_existed" != "yes" ]; then
+ cp -aPR "$mountpoint"/. "$spec/"
+ fi
+
+ mount -o "bind$options" "$spec" "$mountpoint"
+ fi
+elif [ -f "$mountpoint" ]; then
+ if [ ! -f "$spec" ]; then
+ cp -aP "$mountpoint" "$spec"
+ fi
+
+ mount -o "bind$options" "$spec" "$mountpoint"
+fi