#!/bin/sh
# Wrapper script for use of the tsocks(8) transparent socksification library
#
# There are three forms of usage for this script:
#
# /usr/bin/tsocks program [program arguments...]
#
# This form sets the users @LD_PRELOAD@ environment variable so that tsocks(8) 
# will be loaded to socksify the application then executes the specified 
# program (with the provided arguments). The following simple example might 
# be used to telnet to www.foo.org via a tsocks.conf(5) configured socks server:
#
# /usr/bin/tsocks telnet www.foo.org
#
# The second form allows for tsocks(8) to be switched on and off for a 
# session (that is, it adds and removes tsocks from the @LD_PRELOAD@ environment
# variable). This form must be _sourced_ into the user's existing session
# (and will only work with bourne shell users):
#
# . /usr/bin/tsocks on
# telnet www.foo.org 
# . /usr/bin/tsocks off
# 
# Or
# 
# source /usr/bin/tsocks on
# telnet www.foo.org
# source /usr/bin/tsocks off
#
# The third form creates a new shell with @LD_PRELOAD@ set and is achieved
# simply by running the script with no arguments 
# 
# /usr/bin/tsocks
#
# When finished the user can simply terminate the shell with 'exit'
# 
# This script is originally from the debian tsocks package by 
# Tamas Szerb <toma@rulez.org>

if [ $# = 0 ] ; then
   echo "$0: insufficient arguments"
   exit
fi

LIBDIR="@libdir@"
LIB_NAME="libtsocks"
SHLIB_EXT="@SHLIB_EXT@"
SHLIB="${LIBDIR}/${LIB_NAME}.${SHLIB_EXT}"

function show() {
    echo "@LD_PRELOAD@         = \"$@LD_PRELOAD@\""
}
        
case "$1" in
	on)
		if [ -z "$@LD_PRELOAD@" ]
			then
                echo "Setting @LD_PRELOAD@ ..."
				export @LD_PRELOAD@="${SHLIB}"
			else
                echo "Appending to @LD_PRELOAD@ ..."
				echo $@LD_PRELOAD@ | grep -q "${SHLIB}" || \
				export @LD_PRELOAD@="${SHLIB} $@LD_PRELOAD@"
		fi
        show
	;;
	off)
        echo "Removing ${SHLIB} from @LD_PRELOAD@ ..."
		export @LD_PRELOAD@=`echo -n $@LD_PRELOAD@ | sed 's#@libdir@/libtsocks\.@SHLIB_EXT@ *##'`
		if [ -z "$@LD_PRELOAD@" ]
			then
				unset @LD_PRELOAD@
		fi
        show
	;;
	show|sh)
		show
	;;
	-h|-?)
      echo "$0: Please see tsocks(1) or read comment at top of $0"
   ;;
	*)
		if [ -z "$@LD_PRELOAD@" ]
		then
			export @LD_PRELOAD@="${SHLIB}"
		else
			echo $@LD_PRELOAD@ | grep -q "${SHLIB}" || \
			export @LD_PRELOAD@="${SHLIB} $@LD_PRELOAD@"
		fi

		if [ $# = 0 ]
		then
			${SHELL:-/bin/sh}
		fi

		if [ $# -gt 0 ]
		then
			exec "$@"
		fi
	;;
esac

#EOF