functions

   1 #!/bin/sh
   2 #
   3 # geninitrd functions
   4
   5 # Find root device from fstab.
   6 #
   7 # @param        string  $fstab location of /etc/fstab
   8 # @output       string  root device: /dev/hda1, /dev/sys/rootfs, etc
   9 # @return       false on failure
  10 #
  11 # Sets global variables:
  12 # - $rootdev
  13 # - $rootFS
  14 #
  15 find_root() {
  16         local fstab="$1"
  17         local function="${PROGRAM:+$PROGRAM: }find_root"
  18
  19         eval $(awk '/^[\t ]*#/ {next} {if ( $2 == "/" ) {print "rootdev=\"" $1 "\"\nrootFs=\"" $3 "\""}}' $fstab)
  20         if [ -z "$rootdev" ]; then
  21                 echo >&2 "$function: can't find real device for rootfs"
  22                 return 1
  23         fi
  24
  25         case $rootdev in
  26         LABEL=*)
  27                 if [ ! -x /sbin/blkid ]; then
  28                         echo >&2 "$function: /sbin/blkid is missing"
  29                         return 2
  30                 fi
  31
  32                 local label=${rootdev#"LABEL="}
  33                 local dev=$(/sbin/blkid -t LABEL="$label" -o device)
  34                 if [ "$dev" -a -r "$dev" ]; then
  35                         rootdev=$dev
  36                 fi
  37                 ;;
  38
  39         UUID=*)
  40                 if [ ! -x /sbin/blkid ]; then
  41                         echo >&2 "$function: /sbin/blkid is missing"
  42                         return 2
  43                 fi
  44
  45                 local uuid=${rootdev#"UUID="}
  46                 local dev=$(/sbin/blkid -t UUID="$uuid" -o device)
  47
  48                 if [ "$dev" -a -r "$dev" ]; then
  49                         rootdev=$dev
  50                 fi
  51                 ;;
  52         esac
  53
  54         if [ ! -r "$rootdev" ]; then
  55                 echo >&2 "$function: can't find real device for $rootdev"
  56                 return 1
  57         fi
  58
  59         return 0
  60 }