src/vlock.sh

   1 #!%BOURNE_SHELL%
   2
   3 # ignore some signals
   4 trap : HUP INT QUIT TSTP
   5
   6 VLOCK_ALL=%PREFIX%/sbin/vlock-all
   7 VLOCK_NEW=%PREFIX%/sbin/vlock-new
   8 VLOCK_NOSYSRQ=%PREFIX%/sbin/vlock-nosysrq
   9 VLOCK_CURRENT=%PREFIX%/sbin/vlock-current
  10 VLOCK_VERSION=%VLOCK_VERSION%
  11
  12 print_help() {
  13   echo >&2 "vlock: locks virtual consoles, saving your current session."
  14   echo >&2 "Usage: vlock [options]"
  15   echo >&2 "       Where [options] are any of:"
  16   echo >&2 "-c or --current: lock only this virtual console, allowing user to"
  17   echo >&2 "       switch to other virtual consoles."
  18   echo >&2 "-a or --all: lock all virtual consoles by preventing other users"
  19   echo >&2 "       from switching virtual consoles."
  20   echo >&2 "-n or --new: allocate a new virtual console before locking,"
  21   echo >&2 "       implies --all."
  22   echo >&2 "-s or --disable-sysrq: disable sysrq while consoles are locked to"
  23   echo >&2 "       prevent killing vlock with SAK, requires --all."
  24   echo >&2 "-v or --version: Print the version number of vlock and exit."
  25   echo >&2 "-h or --help: Print this help message and exit."
  26   exit $1
  27 }
  28
  29 checked_exec() {
  30   if [ -f "$1" ] && [ ! -x "$1" ] ; then
  31     echo >&2 "vlock: cannot execute \`$1': Permission denied"
  32     echo >&2 "Please check the documentation for more information."
  33     exit 1
  34   else
  35     exec "$@"
  36   fi
  37 }
  38
  39 main() {
  40   local opts lock_all lock_new nosysrq
  41
  42   opts=`getopt -o acnsvh --long current,all,new,disable-sysrq,version,help \
  43         -n vlock -- "$@"`
  44
  45   if [ $? -ne 0 ] ; then
  46     print_help 1
  47   fi
  48
  49   eval set -- "$opts"
  50
  51   lock_all=0
  52   lock_new=0
  53   nosysrq=0
  54
  55   while true ; do
  56     case "$1" in
  57       -a|--all)
  58         lock_all=1
  59         shift
  60         ;;
  61       -c|--current)
  62         lock_all=0
  63         shift
  64         ;;
  65       -s|--disable-sysrq)
  66         nosysrq=1
  67         shift
  68         ;;
  69       -n|--new)
  70         lock_new=1
  71         lock_all=1
  72         shift
  73         ;;
  74       -h|--help)
  75        print_help 0
  76        ;;
  77       -v|--version)
  78         echo "vlock version $VLOCK_VERSION" >&2
  79         exit
  80         ;;
  81       --) shift ; break ;;
  82       *)
  83         echo "getopt error: $1" >&2
  84         exit 1
  85         ;;
  86     esac
  87   done
  88
  89   if [ $lock_new -ne 0 ] ; then
  90     # work around an annoying X11 bug
  91     sleep 1
  92   fi
  93
  94   if [ $lock_all -ne 0 ] ; then
  95     VLOCK_MESSAGE="\
  96 The entire console display is now completely locked.
  97 You will not be able to switch to another virtual console.
  98 "
  99     export VLOCK_MESSAGE
 100
 101     if [ $nosysrq -ne 0 ] ; then
 102       if [ $lock_new -ne 0 ] ; then
 103         export VLOCK_NEW=1
 104       else
 105         unset VLOCK_NEW
 106       fi
 107
 108       checked_exec "$VLOCK_NOSYSRQ"
 109     elif [ $lock_new -ne 0 ] ; then
 110       checked_exec "$VLOCK_NEW"
 111     else
 112       checked_exec "$VLOCK_ALL"
 113     fi
 114   else
 115     VLOCK_MESSAGE="This TTY is now locked."
 116     export VLOCK_MESSAGE
 117
 118     checked_exec "$VLOCK_CURRENT"
 119   fi
 120 }
 121
 122 main "$@"