[OE-core] [PATCH V2 6/6] initscripts: add read-only-rootfs-hook.sh script

[ChenQi]

V2 is a rebase against the latest master branch, which solves some 
conflicts in initscripts_1.0.bb file.

Because only this patch [6/6] had conflicts, I only sent out version 2 
of this patch.

Cheers,
Chen Qi

On 01/29/2013 02:17 PM, Qi.Chen at windriver.com wrote:
> From: Chen Qi <Qi.Chen at windriver.com>
>
> Add read-only-rootfs-hook.sh script to support a read-only rootfs.
> This script makes a union mount of /var/lib and /var/volatile/lib,
> making /var/lib directory writable.
>
> [YOCTO #3406]
>
> Signed-off-by: Chen Qi <Qi.Chen at windriver.com>
> ---
>   .../initscripts-1.0/read-only-rootfs-hook.sh       |   19 +++++++++++++++++++
>   meta/recipes-core/initscripts/initscripts_1.0.bb   |    3 +++
>   2 files changed, 22 insertions(+)
>   create mode 100644 meta/recipes-core/initscripts/initscripts-1.0/read-only-rootfs-hook.sh
>
> diff --git a/meta/recipes-core/initscripts/initscripts-1.0/read-only-rootfs-hook.sh b/meta/recipes-core/initscripts/initscripts-1.0/read-only-rootfs-hook.sh
> new file mode 100644
> index 0000000..3a295ee
> --- /dev/null
> +++ b/meta/recipes-core/initscripts/initscripts-1.0/read-only-rootfs-hook.sh
> @@ -0,0 +1,19 @@
> +#!/bin/sh
> +
> +. /etc/default/rcS
> +
> +[ "$ROOTFS_READ_ONLY" = "no" ] && exit 0
> +
> +# Make sure unionfs is in /proc/filesystems
> +if ! grep -q unionfs /proc/filesystems; then
> +    echo "ERROR: unionfs not supported by kernel!"
> +    exit 1
> +fi
> +
> +mkdir -p /var/volatile/lib
> +mount -t unionfs -o dirs=/var/volatile/lib:/var/lib=ro none /var/lib
> +
> +if [ $? != 0 ]; then
> +    echo "ERROR: Union mount failed!"
> +    exit 1
> +fi
> diff --git a/meta/recipes-core/initscripts/initscripts_1.0.bb b/meta/recipes-core/initscripts/initscripts_1.0.bb
> index 69b9bfb..68f8034 100644
> --- a/meta/recipes-core/initscripts/initscripts_1.0.bb
> +++ b/meta/recipes-core/initscripts/initscripts_1.0.bb
> @@ -28,6 +28,7 @@ SRC_URI = "file://functions \
>              file://sysfs.sh \
>              file://device_table.txt \
>              file://populate-volatile.sh \
> +           file://read-only-rootfs-hook.sh \
>              file://volatiles \
>              file://save-rtc.sh \
>              file://GPLv2.patch"
> @@ -85,6 +86,7 @@ do_install () {
>   	install -m 0755    ${WORKDIR}/devpts		${D}${sysconfdir}/default
>   	install -m 0755    ${WORKDIR}/sysfs.sh		${D}${sysconfdir}/init.d
>   	install -m 0755    ${WORKDIR}/populate-volatile.sh ${D}${sysconfdir}/init.d
> +	install -m 0755    ${WORKDIR}/read-only-rootfs-hook.sh ${D}${sysconfdir}/init.d
>   	install -m 0755    ${WORKDIR}/save-rtc.sh	${D}${sysconfdir}/init.d
>   	install -m 0644    ${WORKDIR}/volatiles		${D}${sysconfdir}/default/volatiles/00_core
>   
> @@ -116,6 +118,7 @@ do_install () {
>   	update-rc.d -r ${D} bootmisc.sh start 55 S .
>   	update-rc.d -r ${D} sysfs.sh start 02 S .
>   	update-rc.d -r ${D} populate-volatile.sh start 37 S .
> +	update-rc.d -r ${D} read-only-rootfs-hook.sh start 41 S .
>   	update-rc.d -r ${D} devpts.sh start 38 S .
>   	if [ "${TARGET_ARCH}" = "arm" ]; then
>   	        update-rc.d -r ${D} alignment.sh start 06 S .