populate-volatile.sh: detect the change of configuration files

In case the configuration files are modified by user, the cached script,
/etc/volatile.cache should not be executed. Instead, the configuration
files should be parsed again and generate the new cache. Otherwise, the
user modifications take no effect which would obviously confuse users.

Signed-off-by: Chen Qi <Qi.Chen@windriver.com>

diff --git a/meta/recipes-core/initscripts/initscripts-1.0/populate-volatile.sh b/meta/recipes-core/initscripts/initscripts-1.0/populate-volatile.sh
index 904037eeaa59a928da954c443fe9fb7135e881fb..eaf0f1c557ac843165db3e0617dfc1a4b35aae89 100755 (executable)
--- a/meta/recipes-core/initscripts/initscripts-1.0/populate-volatile.sh
+++ b/meta/recipes-core/initscripts/initscripts-1.0/populate-volatile.sh
@@ -204,9 +204,25 @@ do
 done
 exec 9>&-
 
-if test -e ${ROOT_DIR}/etc/volatile.cache -a "$VOLATILE_ENABLE_CACHE" = "yes" -a "x$1" != "xupdate" -a "x$clearcache" = "x0"
+# Check whether configuration files have changed, if so, the cache needs to be removed
+# and generated again
+CACHE_MATCH="no"
+CACHE_DATA="${ROOT_DIR}/etc/.volatile.cache.data"
+CACHE_TMP="${ROOT_DIR}/etc/.volatile.cache.tmp"
+VOLATILE_CONFFILES="${ROOT_DIR}/etc/default/volatiles/*"
+if [ "$VOLATILE_ENABLE_CACHE" = "yes" ]; then
+       stat -c '%s %Y %n' $VOLATILE_CONFFILES | awk -F/ '{print $1 " " $NF;}' > $CACHE_TMP
+       if [ -e $CACHE_DATA ]; then
+               if cmp $CACHE_DATA $CACHE_TMP > /dev/null; then
+                       CACHE_MATCH="yes"
+               fi
+       fi
+fi
+
+if test -e ${ROOT_DIR}/etc/volatile.cache -a "$VOLATILE_ENABLE_CACHE" = "yes" -a "x$1" != "xupdate" -a "x$clearcache" = "x0" -a "$CACHE_MATCH" = "yes"
 then
        sh ${ROOT_DIR}/etc/volatile.cache
+       [ -e $CACHE_TMP ] && rm $CACHE_TMP
 else
        rm -f ${ROOT_DIR}/etc/volatile.cache ${ROOT_DIR}/etc/volatile.cache.build
        for file in `ls -1 "${CFGDIR}" | sort`; do
@@ -214,6 +230,7 @@ else
        done
 
        [ -e ${ROOT_DIR}/etc/volatile.cache.build ] && sync && mv ${ROOT_DIR}/etc/volatile.cache.build ${ROOT_DIR}/etc/volatile.cache
+       [ -e $CACHE_TMP ] && mv $CACHE_TMP $CACHE_DATA
 fi
 
 if [ -z "${ROOT_DIR}" ] && [ -f /etc/ld.so.cache ] && [ ! -f /var/run/ld.so.cache ]