src/vlock.sh

   1 #!%BOURNE_SHELL%
   2
   3 # exit on error
   4 set -e
   5
   6 # ignore some signals
   7 trap : HUP INT QUIT TSTP
   8
   9 VLOCK_ALL=%PREFIX%/sbin/vlock-all
  10 VLOCK_NEW=%PREFIX%/sbin/vlock-new
  11 VLOCK_NOSYSRQ=%PREFIX%/sbin/vlock-nosysrq
  12 VLOCK_CURRENT=%PREFIX%/sbin/vlock-current
  13 VLOCK_VERSION=%VLOCK_VERSION%
  14
  15 print_help() {
  16   echo >&2 "vlock: locks virtual consoles, saving your current session."
  17   echo >&2 "Usage: vlock [options]"
  18   echo >&2 "       Where [options] are any of:"
  19   echo >&2 "-c or --current: lock only this virtual console, allowing user to"
  20   echo >&2 "       switch to other virtual consoles."
  21   echo >&2 "-a or --all: lock all virtual consoles by preventing other users"
  22   echo >&2 "       from switching virtual consoles."
  23   echo >&2 "-n or --new: allocate a new virtual console before locking,"
  24   echo >&2 "       implies --all."
  25   echo >&2 "-s or --disable-sysrq: disable sysrq while consoles are locked to"
  26   echo >&2 "       prevent killing vlock with SAK, requires --all."
  27   echo >&2 "-v or --version: Print the version number of vlock and exit."
  28   echo >&2 "-h or --help: Print this help message and exit."
  29   exit $1
  30 }
  31
  32 checked_exec() {
  33   if [ -f "$1" ] && [ ! -x "$1" ] ; then
  34     echo >&2 "vlock: cannot execute \`$1': Permission denied"
  35     echo >&2 "Please check the documentation for more information."
  36     exit 1
  37   else
  38     exec "$@"
  39   fi
  40 }
  41
  42 main() {
  43   local opts lock_all lock_new nosysrq
  44
  45   ( getopt -T >/dev/null )
  46
  47   if [ $? -eq 4 ] ; then
  48     # gnu getopt
  49     opts=`getopt -o acnsvh --long current,all,new,disable-sysrq,version,help \
  50           -n vlock -- "$@"`
  51   else
  52     opts=`getopt acnsvh "$@"`
  53   fi
  54
  55   if [ $? -ne 0 ] ; then
  56     print_help 1
  57   fi
  58
  59   eval set -- "$opts"
  60
  61   lock_all=0
  62   lock_new=0
  63   nosysrq=0
  64
  65   while : ; do
  66     case "$1" in
  67       -a|--all)
  68         lock_all=1
  69         shift
  70         ;;
  71       -c|--current)
  72         lock_all=0
  73         shift
  74         ;;
  75       -s|--disable-sysrq)
  76         nosysrq=1
  77         shift
  78         ;;
  79       -n|--new)
  80         lock_new=1
  81         lock_all=1
  82         shift
  83         ;;
  84       -h|--help)
  85        print_help 0
  86        ;;
  87       -v|--version)
  88         echo "vlock version $VLOCK_VERSION" >&2
  89         exit
  90         ;;
  91       --) shift ; break ;;
  92       *)
  93         echo "getopt error: $1" >&2
  94         exit 1
  95         ;;
  96     esac
  97   done
  98
  99   if [ $lock_new -ne 0 ] && [ -n "$DISPLAY" ] ; then
 100     # work around an annoying X11 bug
 101     sleep 1
 102   fi
 103
 104   if [ $lock_all -ne 0 ] ; then
 105     : ${VLOCK_MESSAGE:="\
 106 The entire console display is now completely locked.
 107 You will not be able to switch to another virtual console.
 108
 109 Please press [ENTER] to unlock."}
 110     export VLOCK_MESSAGE
 111
 112     if [ $nosysrq -ne 0 ] ; then
 113       if [ $lock_new -ne 0 ] ; then
 114         export VLOCK_NEW=1
 115       else
 116         unset VLOCK_NEW
 117       fi
 118
 119       checked_exec "$VLOCK_NOSYSRQ"
 120     elif [ $lock_new -ne 0 ] ; then
 121       checked_exec "$VLOCK_NEW"
 122     else
 123       checked_exec "$VLOCK_ALL"
 124     fi
 125   else
 126     : ${VLOCK_MESSAGE:="\
 127 This TTY is now locked.
 128
 129 Please press [ENTER] to unlock."}
 130     export VLOCK_MESSAGE
 131
 132     checked_exec "$VLOCK_CURRENT"
 133   fi
 134 }
 135
 136 main "$@"