udev-cache: refactor sysconf generation

The current system configuration needs to be generated both inside
udev (to compare against the cached system configuration) and
udev-cache (to regenerate the cached system configuration). Use a single
function definition for this task, duplicated across both initscripts.
This also allows administrators to modify it for machine-specific
requirements.

(From OE-Core rev: 34957afcfe663eed4f5ebec0891a84467e67a48d)

Signed-off-by: Richard Tollerton <rich.tollerton@ni.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

2 files changed, 18 insertions, 5 deletions

diff --git a/meta/recipes-core/udev/udev/init b/meta/recipes-core/udev/udev/init
index 337b6d4c11..96578bc15b 100644
--- a/meta/recipes-core/udev/udev/init
+++ b/meta/recipes-core/udev/udev/init
@@ -17,6 +17,16 @@ export TZ=/etc/localtime
 SYSCONF_CACHED="/etc/udev/cache.data"
 SYSCONF_TMP="/dev/shm/udev.cache"
 DEVCACHE_REGEN="/dev/shm/udev-regen" # create to request cache regen
+
+# A list of files which are used as a criteria to judge whether the udev cache could be reused.
+CMP_FILE_LIST="/proc/version /proc/cmdline /proc/devices"
+[ -f /proc/atags ] && CMP_FILE_LIST="$CMP_FILE_LIST /proc/atags"
+
+# Command to compute system configuration.
+sysconf_cmd () {
+        cat -- $CMP_FILE_LIST
+}
+
 [ -f /etc/default/udev-cache ] && . /etc/default/udev-cache
 [ -f /etc/udev/udev.conf ] && . /etc/udev/udev.conf
 [ -f /etc/default/rcS ] && . /etc/default/rcS
@@ -52,12 +62,9 @@ case "$1" in
     mkdir -m 1777 -p /var/volatile/tmp
 
     # Cache handling.
-    # A list of files which are used as a criteria to judge whether the udev cache could be reused.
-    CMP_FILE_LIST="/proc/version /proc/cmdline /proc/devices"
-    [ -f /proc/atags ] && CMP_FILE_LIST="$CMP_FILE_LIST /proc/atags"
     if [ "$DEVCACHE" != "" ]; then
             if [ -e $DEVCACHE ]; then
-                    cat -- "$CMP_FILE_LIST" > "$SYSCONF_TMP"
+                    sysconf_cmd > "$SYSCONF_TMP"
                     if cmp $SYSCONF_CACHED $SYSCONF_TMP >/dev/null; then
                             tar xmf $DEVCACHE -C / -m
                             not_first_boot=1
diff --git a/meta/recipes-core/udev/udev/udev-cache b/meta/recipes-core/udev/udev/udev-cache
index 814ef54c3c..4d50876b64 100644
--- a/meta/recipes-core/udev/udev/udev-cache
+++ b/meta/recipes-core/udev/udev/udev-cache
@@ -24,6 +24,12 @@ DEVCACHE_REGEN="/dev/shm/udev-regen" # create to request cache regen
 # A list of files which are used as a criteria to judge whether the udev cache could be reused.
 CMP_FILE_LIST="/proc/version /proc/cmdline /proc/devices"
 [ -f /proc/atags ] && CMP_FILE_LIST="$CMP_FILE_LIST /proc/atags"
+
+# Command to compute system configuration.
+sysconf_cmd () {
+        cat -- $CMP_FILE_LIST
+}
+
 [ -f /etc/default/udev-cache ] && . /etc/default/udev-cache
 
 if [ "$ROOTFS_READ_ONLY" = "yes" ]; then
@@ -34,7 +40,7 @@ fi
 if [ "$DEVCACHE" != "" -a -e "$DEVCACHE_REGEN" ]; then
         echo "Populating dev cache"
         udevadm control --stop-exec-queue
-        cat -- $CMP_FILE_LIST > "$SYSCONF_TMP"
+        sysconf_cmd > "$SYSCONF_TMP"
         find /dev -xdev \( -type b -o -type c -o -type l \) | cut -c 2- \
                 | xargs tar cf "${DEVCACHE_TMP}" -T-
         gzip < "${DEVCACHE_TMP}" > "$DEVCACHE"