Patrick Williams | c124f4f | 2015-09-15 14:41:29 -0500 | [diff] [blame] | 1 | #!/bin/sh -e |
| 2 | |
| 3 | ### BEGIN INIT INFO |
| 4 | # Provides: udev-cache |
| 5 | # Required-Start: mountall |
| 6 | # Required-Stop: |
| 7 | # Default-Start: S |
| 8 | # Default-Stop: |
| 9 | # Short-Description: cache /dev to speedup the udev next boot |
| 10 | ### END INIT INFO |
| 11 | |
| 12 | export TZ=/etc/localtime |
| 13 | |
| 14 | [ -r /proc/mounts ] || exit 1 |
| 15 | [ -x @UDEVD@ ] || exit 1 |
| 16 | [ -d /sys/class ] || exit 1 |
| 17 | |
| 18 | [ -f /etc/default/rcS ] && . /etc/default/rcS |
| 19 | DEVCACHE_TMP="/dev/shm/udev-cache-tmp.tar" |
| 20 | SYSCONF_CACHED="/etc/udev/cache.data" |
| 21 | SYSCONF_TMP="/dev/shm/udev.cache" |
| 22 | DEVCACHE_REGEN="/dev/shm/udev-regen" # create to request cache regen |
| 23 | |
| 24 | # A list of files which are used as a criteria to judge whether the udev cache could be reused. |
| 25 | CMP_FILE_LIST="/proc/version /proc/cmdline /proc/devices" |
| 26 | [ -f /proc/atags ] && CMP_FILE_LIST="$CMP_FILE_LIST /proc/atags" |
| 27 | |
| 28 | # List of files whose metadata (size/mtime/name) will be included in cached |
| 29 | # system state. |
| 30 | META_FILE_LIST="lib/udev/rules.d/* etc/udev/rules.d/*" |
| 31 | |
| 32 | # Command to compute system configuration. |
| 33 | sysconf_cmd () { |
| 34 | cat -- $CMP_FILE_LIST |
| 35 | stat -c '%s %Y %n' -- $META_FILE_LIST | awk -F/ '{print $1 " " $NF;}' |
| 36 | } |
| 37 | |
| 38 | [ -f /etc/default/udev-cache ] && . /etc/default/udev-cache |
| 39 | |
| 40 | if [ "$ROOTFS_READ_ONLY" = "yes" ]; then |
| 41 | [ "$VERBOSE" != "no" ] && echo "udev-cache: read-only rootfs, skip generating udev-cache" |
| 42 | exit 0 |
| 43 | fi |
| 44 | |
| 45 | [ "$DEVCACHE" != "" ] || exit 0 |
| 46 | [ "${VERBOSE}" == "no" ] || echo -n "udev-cache: checking for ${DEVCACHE_REGEN}... " |
| 47 | if ! [ -e "$DEVCACHE_REGEN" ]; then |
| 48 | [ "${VERBOSE}" == "no" ] || echo "not found." |
| 49 | exit 0 |
| 50 | fi |
| 51 | [ "${VERBOSE}" == "no" ] || echo "found." |
| 52 | echo "Populating dev cache" |
| 53 | |
| 54 | err_cleanup () { |
| 55 | echo "udev-cache: update failed!" |
| 56 | udevadm control --start-exec-queue |
| 57 | rm -f -- "$SYSCONF_TMP" "$DEVCACHE_TMP" "$DEVCACHE" "$SYSCONF_CACHED" |
| 58 | } |
| 59 | |
| 60 | ( |
| 61 | set -e |
| 62 | trap 'err_cleanup' EXIT |
| 63 | udevadm control --stop-exec-queue |
| 64 | sysconf_cmd > "$SYSCONF_TMP" |
| 65 | find /dev -xdev \( -type b -o -type c -o -type l \) | cut -c 2- \ |
| 66 | | xargs tar cf "${DEVCACHE_TMP}" |
| 67 | gzip < "${DEVCACHE_TMP}" > "$DEVCACHE" |
| 68 | rm -f "${DEVCACHE_TMP}" |
| 69 | mv "$SYSCONF_TMP" "$SYSCONF_CACHED" |
| 70 | udevadm control --start-exec-queue |
| 71 | rm -f "$DEVCACHE_REGEN" |
| 72 | trap - EXIT |
| 73 | ) & |
| 74 | |
| 75 | exit 0 |