path: root/utils/sb2

#!/bin/bash
# Copyright (C) 2006,2007 Lauri Leukkunen <lle@rahina.org>
# Licensed under GPL version 2

function version()
{
	cat $SBOX_DIR/share/scratchbox2/version
}

function usage()
{
	cat <<EOF
sb2 - crosscompiling environment
Usage:
    sb2 [OPTION]... [COMMAND] [PARAMETERS]

If no COMMAND is given, a bash shell in scratchbox2 environment is started.

Options:
    -v           display version
    -L level     enable logging (levels=one of error,warning,notice,info,debug,noise,noise2,noise3)
    -d           debug mode: log all redirections (logging level=debug)
    -h           print this help
    -t TARGET    target to use, use sb2-config -d TARGET to set a default
    -e           emulation mode
    -m MODE      use mapping mode MODE
    -M file      read mapping rules from "file"
    -s DIRECTORY load mapping scripts from alternative location
    -Q BUGLIST   emulate bugs of the old scratchbox 1 (BUGLIST consists of
                 letters: 'x' enables exec permission checking bug emulation)
    -r           do not create reverse mapping rules
    -O options   set options for the selected mapping mode ("options" is
                 a mode-specific string)
    -R           use simulated root permissions (currently activates
                 "fakeroot" for this functionality)
    -S file      Write session information to "file" (see option -J)
    -J file      Don't create a new session; join an existing one (see -S) 
    -D file      delete an old session (see -S). Warning: this does not
                 check if the session is still in use!
    -W dir       Use "dir" as the session directory when creating the session
                 ("dir" must be absolute path and must not exist. N.B. long 
                 pathnames here may cause trouble with socket operations) 
    -c           When creating a session, also create a private copy
                 of target_root (rootstrap). Note that this can be
                 really slow, depending on the size of the orig.target_root
    -C dir       When creating a session, create copy of "dir" and use it as the 
                 target_root (rootstrap).
    -T dir       use "dir" as tools_root (overriding the value from config file)

Examples:
    sb2 ./configure
    sb2 make
    sb2 -e make install
    sb2 -m emulate make install
EOF
	exit 2
}

function exit_error()
{
	echo "sb2: Error: $@"
	exit 1
}

function sanity_check()
{
	if [ `id -u` = 0 ]; then
		exit_error "Do not use sbox2 as root!"
	fi
	# check that most important host and target files exist
}

# Collect & write mapping- and policy rules to $SBOX_SESSION_DIR/rules/*
#
# Parameters:
#  - output file name
#  - mapping mode name
#  - list of rule files (if specified by the -M option)
function write_rules_to_session_dir()
{
	output_file_name=$1
	mapmode_name=$2
	shift 2
	input_files="$@"

	cat >$output_file_name <<END
-- Rules for session $SBOX_SESSION_DIR
-- Automatically generated file, do not edit.
--
END
	
	for f in $input_files; do
		if [ -r $f ]; then
			echo "-- [ $f ]" >>$output_file_name
			cat $f >>$output_file_name
		else
			echo "-- [ Failed to read $f ]" >>$output_file_name
		fi
	done
}

# Create reverse rules. Since that will be done using sb2-show, the environment
# must to be ready => this function can be called only just before the shell
# is executed at end of this script.
function create_reverse_rules()
{
	for ammf in $SBOX_SESSION_DIR/rules/*.lua; do
		amm_base=`basename $ammf .lua`

		SBOX_SESSION_MODE=$amm_base sb2-monitor \
			-L $SBOX_LIBSB2 -- $SBOX_DIR/bin/sb2-show \
			execluafile \
			$SBOX_SESSION_DIR/lua_scripts/create_reverse_rules.lua \
			>$SBOX_SESSION_DIR/rev_rules/$amm_base.lua
	done
}

#
# Generates argvmods for cross-compilers and misc binaries.
# Generated files are placed under $SBOX_SESSION_DIR/argvmods/.
#
function create_argvmods_rules()
{
	/bin/mkdir -p $SBOX_SESSION_DIR/argvmods
	SBOX_ARGVMODS_SOURCE_FILE="argvenvp_misc.lua" sb2-monitor \
	    -L $SBOX_LIBSB2 -- $SBOX_DIR/bin/sb2-show \
	    execluafile \
	    $SBOX_SESSION_DIR/lua_scripts/create_argvmods_rules.lua \
	    >$SBOX_SESSION_DIR/argvmods/argvmods_misc.lua
	SBOX_ARGVMODS_SOURCE_FILE="argvenvp_gcc.lua" sb2-monitor \
	    -L $SBOX_LIBSB2 -- $SBOX_DIR/bin/sb2-show \
	    execluafile \
	    $SBOX_SESSION_DIR/lua_scripts/create_argvmods_rules.lua \
	    >$SBOX_SESSION_DIR/argvmods/argvmods_gcc.lua
}

# Create some additional rules for the default mapping mode:
function create_argvmods_usr_bin_rules()
{
	default_rule=$1

	for ammf in $SBOX_SESSION_DIR/rules/Default.lua \
		    $SBOX_SESSION_DIR/rules/$SBOX_MAPMODE.lua; do
		amm_base=`basename $ammf .lua`

		SBOX_ARGVMODS_USR_BIN_DEFAULT_RULE="$default_rule" \
		SBOX_SESSION_MODE=$amm_base sb2-monitor \
			-L $SBOX_LIBSB2 -- $SBOX_DIR/bin/sb2-show \
			execluafile \
			$SBOX_SESSION_DIR/lua_scripts/create_argvmods_usr_bin_rules.lua \
			>$SBOX_SESSION_DIR/rules/$amm_base.ARGVMODS
		# add the generated rules to the beginning of the rule file
		cat $SBOX_SESSION_DIR/rules/$amm_base.ARGVMODS $ammf \
		    >$SBOX_SESSION_DIR/rules/$amm_base.NEW
		mv $SBOX_SESSION_DIR/rules/$amm_base.NEW $ammf
		rm $SBOX_SESSION_DIR/rules/$amm_base.ARGVMODS
	done
}

function set_and_check_SBOX_TARGET()
{
	if [ -z "$SBOX_TARGET" ]; then
		if [ -r ~/.scratchbox2/config ]; then
			. ~/.scratchbox2/config
		fi
		SBOX_TARGET=$DEFAULT_TARGET
	fi

	if [ -z "$SBOX_TARGET" ]; then
		exit_error "No target specified and none set as default, aborting."
	fi

	if [ ! -e ~/.scratchbox2/$SBOX_TARGET/sb2.config ]; then
		exit_error "Invalid target specified, aborting."
	fi
}

function load_configuration()
{
	#-----------
	# part of the configuration is still stored in the "old format"
	# configuration file, "sb2.config". It is created by "sb2-init"

	. ~/.scratchbox2/$SBOX_TARGET/sb2.config
	# Remember where SBOX_TARGET_ROOT was in the configuration file
	SBOX_TARGET_ROOT_in_config_file=$SBOX_TARGET_ROOT

	#-----------
	# "New" config system stores configuration to various files
	# in sb2.config.d directory, and the configuration is automatically
	# upgraded whenever needed:
	
	# check if we need to upgrade configuration:
	if [ ! -f ~/.scratchbox2/$SBOX_TARGET/sb2.config.d/config-stamp.14 ]; then
		$SBOX_DIR/share/scratchbox2/scripts/sb2-upgrade-config \
			$SBOX_TARGET
		if [ $? != 0 ]; then
			echo "Failed to upgrade configuration files" >&2
			exit 1
		fi
	fi

	#-----------
	# Read in primary toolchain config, if it has been defined
	if [ -f $HOME/.scratchbox2/$TARGET/sb2.config.d/gcc.config.sh ]; then
		. $HOME/.scratchbox2/$TARGET/sb2.config.d/gcc.config.sh
	fi
}

function clone_target_root_dir_from()
{
	source_directory=$1

	echo "Copying target root from $source_directory..."
	# cp -Rp does not preserve hard links, but cpio does
	(cd $source_directory; find . -depth -print |
		cpio -pamd $SBOX_SESSION_DIR/target_root)
	#
	# We store path of the original target root here.  It
	# is used later on when libsb2 search path is being formed.
	#
	SBOX_CLONED_TARGET_ROOT=$source_directory
	SBOX_TARGET_ROOT=$SBOX_SESSION_DIR/target_root
	SB2_TEMP_DPKG_ADMIN_DIR=$SBOX_SESSION_DIR/tmp-pkg-db
	mkdir -p $SB2_TEMP_DPKG_ADMIN_DIR
}

function sboxify_environment()
{
	LD_LIBRARY_PATH=$SBOX_DIR/lib/libsb2:$SBOX_DIR/lib64/libsb2:$SBOX_DIR/lib32/libsb2:/emul/lib64/libsb2:/emul/lib32/libsb2
	SBOX_LIBSB2="libsb2.so.1"
	
	load_configuration

	# override SBOX_TOOLS_ROOT if requested by command-line option
	if [ -n "$SBOX_FORCED_TOOLS_ROOT" ]; then
		SBOX_TOOLS_ROOT=$SBOX_FORCED_TOOLS_ROOT
	fi

	# Check that tools exist (or at least the directory exists)
	if [ ! -d "$SBOX_TOOLS_ROOT" ]; then
		exit_error "Tools directory '$SBOX_TOOLS_ROOT' does not exist."
	fi

	if [ -d $SBOX_SESSION_DIR/target_root ]; then
		# A copy of target_root already exists, use that
		# (this may happen when we are joining an old
		# session, see options -J and -c)
		SBOX_TARGET_ROOT=$SBOX_SESSION_DIR/target_root
		SB2_TEMP_DPKG_ADMIN_DIR=$SBOX_SESSION_DIR/tmp-pkg-db
	elif [ "$OPT_CLONE_TARGET_ROOT" == "y" ]; then
		# SBOX_TARGET_ROOT has been set, make a clone of it
		clone_target_root_dir_from $SBOX_TARGET_ROOT
	elif [ -n "$OPT_CLONE_TARGET_ROOT_FROM" ]; then
		if [ -d "$OPT_CLONE_TARGET_ROOT_FROM" ]; then
			# the source is a directory, clone it.
			clone_target_root_dir_from $OPT_CLONE_TARGET_ROOT_FROM
		elif [ ! -e "$OPT_CLONE_TARGET_ROOT_FROM" ]; then
			exit_error "'$OPT_CLONE_TARGET_ROOT_FROM' does not exist."
		else
			exit_error "Don't know how to create target root from '$OPT_CLONE_TARGET_ROOT_FROM'"
		fi
	else
		SB2_TEMP_DPKG_ADMIN_DIR=$HOME/.scratchbox2/$SBOX_TARGET.tmp-pkg-db.$SBOX_MAPMODE
	fi

	# SBOX_MAPMODE has been set, read mode-specific settings
	if [ -f $SBOX_DIR/share/scratchbox2/modeconf/sb2rc.$SBOX_MAPMODE ]; then
		. $SBOX_DIR/share/scratchbox2/modeconf/sb2rc.$SBOX_MAPMODE starting
	fi

	if [ "$SBOX_CONFIG_VERSION" -lt "9" ]; then
		echo "Please run sb2-init for your target"
		echo "to update its sb2.config to work with current version of sb2."
		exit 1
	fi

	if [ -n "$SBOX_DIR" ]; then
		if [ -z "$SBOX_LUA_SCRIPTS" ]; then
			SBOX_LUA_SCRIPTS="$SBOX_DIR/share/scratchbox2/lua_scripts"
		fi
	else
		exit_error "Incorrect target config in ~/.scratchbox2/$SBOX_TARGET/sb2.config"
	fi

	# This refers to the primary toolchain.
	# FIXME: $SBOX_TARGET_TOOLCHAIN_DIR should be removed completely,
	# but currently the "install" mode needs it.
	SBOX_TARGET_TOOLCHAIN_DIR=$(dirname "$SBOX_CROSS_GCC_DIR")

	if [ -z "$SBOX_MODE_PATH" ]; then
		# /sb2/wrappers and /sb2/scripts contain utilities for
		# development support, and are available in the
		# software development modes ("simple" and "devel")
		export PATH=/sb2/wrappers:/sb2/scripts:$HOME/.scratchbox2/$SBOX_TARGET/bin:$SBOX_DIR/bin:$PATH:/sbin:/usr/sbin:$SBOX_TARGET_ROOT/bin:$SBOX_TARGET_ROOT/usr/bin:$SBOX_TARGET_ROOT/usr/local/bin
	else
		export PATH=$SBOX_MODE_PATH
	fi

	# LD_PRELOAD will be set to SBOX_LIBSB2 by sb2-monitor.

	export PS1="[SB2 $SBOX_MAPMODE $SBOX_TARGET] \u@\h \W \$ "
}


function initialize_sb_logging()
{
	cmd_param=$1
	args_param=$2
	if [ "$SBOX_MAPPING_LOGLEVEL" != "" ]; then
		tstamp=`SBOX_DISABLE_MAPPING=1 /bin/date +%Y%m%d-%H%M`
		if [ ! -d $HOME/sb2_logs ]; then
			SBOX_DISABLE_MAPPING=1 mkdir $HOME/sb2_logs 
			echo "Created directory $HOME/sb2_logs for log files"
		fi
		MAPPING_LOGFILE=$HOME/sb2_logs/$cmd_param.$tstamp.$$.log
		export SBOX_MAPPING_LOGFILE=$MAPPING_LOGFILE

		if [ "$SBOX_MAPPING_DEBUG" == "1" ]; then
			# log command:
			echo "##Log from $cmd_param $args_param" >$MAPPING_LOGFILE

			# log initial environment if logging is enabled
			env | sed -e 's/^/#/' >>$MAPPING_LOGFILE
			echo "#SBOX_TARGET_ROOT=$SBOX_TARGET_ROOT" >>$MAPPING_LOGFILE
			echo "#SBOX_TOOLS_ROOT=$SBOX_TOOLS_ROOT" >>$MAPPING_LOGFILE
			echo "#SBOX_MAPMODE=$SBOX_MAPMODE" >>$MAPPING_LOGFILE

			echo "Running scratchbox with these settings:"
			echo "SBOX_LIBSB2 = $SBOX_LIBSB2"
			echo "SBOX_LUA_SCRIPTS = $SBOX_LUA_SCRIPTS"
			echo "SBOX_TOOLS_ROOT = $SBOX_TOOLS_ROOT"
			echo "SBOX_TARGET_ROOT = $SBOX_TARGET_ROOT"
			echo "SBOX_MAPPING_LOGFILE = $SBOX_MAPPING_LOGFILE"
			echo "SBOX_MAPPING_LOGLEVEL = $SBOX_MAPPING_LOGLEVEL"
			echo
		fi
	fi
}

#
# Write variables to $SBOX_SESSION_DIR/sb2-session.conf
# NOTE: this file will be read by lua interpreter and the shell,
# so only simple string assignments are allowed! 
# (even comments are different in Lua and shell scripts..)
function create_common_sb2_conf_file_for_session()
{
	sbox_user_home_dir=$HOME
	if [ -z "$HOME" ]; then
		sbox_user_home_dir="/home/unknown_user"
	fi

	cat <<END >>$SBOX_SESSION_DIR/sb2-session.conf
comment_1=" Common configuration file for Lua and Shell scripts."
comment_2=" Automatically generated file, do not edit."

sbox_target="$SBOX_TARGET"

sbox_dir="$SBOX_DIR"
sbox_workdir="$SBOX_WORKDIR"
sbox_user_home_dir="$sbox_user_home_dir"
sbox_target_toolchain_dir="$SBOX_TARGET_TOOLCHAIN_DIR"

sbox_mapmode="$SBOX_MAPMODE"
sbox_mode_specific_options="$SBOX_MODE_SPECIFIC_OPTIONS"
sbox_target_root="$SBOX_TARGET_ROOT"
sbox_cloned_target_root="$SBOX_CLONED_TARGET_ROOT"
sbox_tools_root="$SBOX_TOOLS_ROOT"
sbox_temp_dpkg_admin_dir="$SB2_TEMP_DPKG_ADMIN_DIR"

sbox_cpu="$SBOX_CPU"
sbox_cputransparency_method="$SBOX_CPUTRANSPARENCY_METHOD"
sbox_sbrsh_config="$SBRSH_CONFIG"

sbox_host_gcc_prefix_list="$SBOX_HOST_GCC_PREFIX_LIST"
sbox_host_gcc_dir="$SBOX_HOST_GCC_DIR"
sbox_extra_host_compiler_args="$SBOX_EXTRA_HOST_COMPILER_ARGS"
sbox_host_gcc_subst_prefix="$SBOX_HOST_GCC_SUBST_PREFIX"
sbox_block_host_compiler_args="$SBOX_BLOCK_HOST_COMPILER_ARGS"

sbox_uname_machine="$SBOX_UNAME_MACHINE"
sbox_libsb2="$SBOX_LIBSB2"

sbox_emulate_sb1_bugs="$SBOX_EMULATE_SB1_BUGS"
END
}

# create $SBOX_SESSION_DIR/gcc-conf.lua
function create_gcc_conf_file_for_session()
{
	gcc_config_files=`ls ~/.scratchbox2/$SBOX_TARGET/sb2.config.d/gcc.config*.lua 2>/dev/null`
	if [ -n "$gcc_config_files" ] ; then
		# Create the configuration file. Do some variable substitutions:
		# "extra_cross_compiler_args" and "extra_cross_ld_args"
		# need absolute paths to the orig. rootstrap location, at least.
		cat $gcc_config_files | \
			sed -e "s:@SBOX_TARGET_ROOT@:$SBOX_TARGET_ROOT:g" \
			>$SBOX_SESSION_DIR/gcc-conf.lua
	fi
}

# write_ld_library_path_replacement_to_exec_config():
#
# Create replacement for LD_LIBRARY_PATH and write it to the created config
# file. This is called first for the tools (tools_root), and if host CPU
# type == target CPU, then this is called again to create settings for
# target_root as well.
#
# This also locates a libsb2.so.1 library which must be used; Several
# possible locations are checked. Tools/target need to get the libsb2.so
# library from a "neutral" place so that it would be possible to
# upgrade/downgrade any component (tools,target_roots or sb2 itself)
# without having to re-configure other components in the system.
function write_ld_library_path_replacement_to_exec_config()
{
	rootdir=$1
	varname=$2
	shift 2
	libsb2_candidates="$@"

	# Build replacement for LD_LIBRARY_PATH:

	# ---- Step 1. Location of libsb2.so
	libsb2_dirname=""
	libsb2_path=""
	if [ -n "$libsb2_candidates" ]
	then
		for l in $libsb2_candidates
		do
			if [ -f $l ]
			then
				# IMPORTANT: $libsb2_dirname and $libsb2_path
				# will be used by
				# write_libsb2_and_ld_so_state_to_exec_config()
				libsb2_dirname=`dirname $l`
				libsb2_path=$l
				break
			fi
		done
	fi

	# ---- Step 2. Directories under $rootdir
	# First, make sure that libsb2 is searched
	liblocations="$SBOX_DIR/lib/libsb2 /usr/lib/libsb2"

	# Include directories listed in ld.so.conf
	if [ -f $rootdir/etc/ld.so.conf ]; then
		lloc2=`egrep '^/' $rootdir/etc/ld.so.conf`
		liblocations="$liblocations $lloc2"
	fi
	# Include directories listed in ld.so.conf.d/*
	if [ -d $rootdir/etc/ld.so.conf.d ]; then
		lloc2=`cat $rootdir/etc/ld.so.conf.d/* 2>/dev/null | egrep '^/'`
		liblocations="$liblocations $lloc2"
	fi

	# Next, force libfakeroot to be searced:
	liblocations="$liblocations /usr/lib/libfakeroot \
		/usr/lib64/libfakeroot /usr/lib32/libfakeroot"

	# Find all directories that are used in the ld.so cache file:
	if [ -x $rootdir/sbin/ldconfig ]; then
		# print contents of the cache, take destination
		# names (the part after "=>"), drop file names (leave
		# directory names, and remove duplicates:
		dirs_in_cache=`$rootdir/sbin/ldconfig -p \
			-C $rootdir/etc/ld.so.cache | 
			fgrep '=>' | 
			sed -e 's/^.*=> //' -e 's:/[^/]*$::' | 
			sort | uniq`
		ld_library_extras_from_cache=$dirs_in_cache
		liblocations="$liblocations $dirs_in_cache"
	fi

	# Create the variable.
	echo "$varname =" >>$SBOX_SESSION_DIR/exec_config.lua
	colon=""
	if [ -n "$libsb2_dirname" ]; then
		echo " \"$colon$libsb2_dirname\" .." >>$SBOX_SESSION_DIR/exec_config.lua
		colon=":"
	fi
	for l in $liblocations; do
		if [ -d $rootdir$l ]; then
			echo " \"$colon$rootdir$l\" .." >>$SBOX_SESSION_DIR/exec_config.lua
			colon=":"
		fi
	done

	# Last, the default locations:
	# (these may be already included by the previous step)
	echo " \"$colon$rootdir/lib\" .." >>$SBOX_SESSION_DIR/exec_config.lua
	colon=":"
	echo " \"$colon$rootdir/usr/lib\" .." >>$SBOX_SESSION_DIR/exec_config.lua

	# Finalize the library search path.
	echo " \"\"" >>$SBOX_SESSION_DIR/exec_config.lua
}

# Test if qemu has "-0 argv0" and "-E envvar=value" flags, and/or
# "-libattr-hack"
function check_qemu_features()
{
	qemu_path=$1

	test_output=`$qemu_path -h | grep '^-0'`
	if [ -n "$test_output" ]; then
		# -0 is supported
		conf_cputransparency_has_argv0_flag="true"
	else
		conf_cputransparency_has_argv0_flag="false"
	fi

	test_output=`$qemu_path -h | grep '^-E'`
	if [ -n "$test_output" ]; then
		# -E is supported
		conf_cputransparency_qemu_has_env_control_flags="true"
	else
		conf_cputransparency_qemu_has_env_control_flags="false"
	fi

	test_output=`$qemu_path -h | grep '^-libattr-hack'`
	if [ -n "$test_output" ]; then
		conf_cputransparency_qemu_has_libattr_hack_flag="true"
	else
		conf_cputransparency_qemu_has_libattr_hack_flag="false"
	fi
}

# Test if the "--argv0" flag is supported by the ld.so
function check_ld_so_argv0_feature()
{
	rootdir=$1
	ld_so_path=$2

	ld_so_argv_flag_works="false" # the default

	# Executing ld.so without any arguments should print 
	# usage information to stderr:
	test_output=`$ld_so_path 2>&1 | grep 'argv0 STRING'`
	if [ -n "$test_output" ]; then
		# description about --argv0 exists!
		ld_so_argv_flag_works="true"
	fi
}

function write_libsb2_and_ld_so_state_to_exec_config()
{
	rootdir=$1
	sb2_installed_varname=$2
	sbox_dir_varname=$3
	ld_so_path_varname=$4
	ld_so_supports_argv0_varname=$5
	libsb2_dir_varname=$6

	# Check if ld.so can be used from $rootdir by 
	# checking that libsb2 has been installed to tools

	if [ -d $rootdir/$SBOX_DIR/lib/libsb2 ]; then
		sbox_dir_2=$rootdir/$SBOX_DIR
	elif [ -d $rootdir/usr/lib/libsb2 ]; then
		sbox_dir_2=$rootdir/usr
	else
		sbox_dir_2=""
	fi

	if [ -z "$libsb2_path" ]; then
		libsb2_path=$sbox_dir_2/lib/libsb2/libsb2.so.1
		libsb2_dirname=""
	fi

	if [ -f $libsb2_path ]; then
		libsb2_dir=`/usr/bin/dirname $libsb2_path`
		echo "-- $libsb2_path" >>$SBOX_SESSION_DIR/exec_config.lua
		echo "$libsb2_dir_varname = \"$libsb2_dir\"" \
		    >>$SBOX_SESSION_DIR/exec_config.lua
		echo "$sb2_installed_varname = true" \
		    >>$SBOX_SESSION_DIR/exec_config.lua
		ld_so_found="yes"
	else
		echo "$sb2_installed_varname = false" >>$SBOX_SESSION_DIR/exec_config.lua
		ld_so_found="no"
	fi

	echo "$sbox_dir_varname = \"$sbox_dir_2\"" >>$SBOX_SESSION_DIR/exec_config.lua

	# check the dynamic linker:

	# First try if the default linker can be used
	ld_so_candidate=$rootdir/lib/ld-linux.so.2
	if [ -f $ld_so_candidate ]; then
		check_ld_so_argv0_feature $rootdir $ld_so_candidate
		if [ "$ld_so_argv_flag_works" != "true" ]; then
			# the default ld.so does not support --argv0.
			# Find out if a replacement has been installed for sb2.
			ld_so_with_version=`readlink $ld_so_candidate`

			# First try if it exists in the same directory where
			# libsb2.so is:
			ld_so_candidate2=$libsb2_dirname/$ld_so_with_version
			if [ -n "$libsb2_dirname" -a -f $ld_so_candidate2 ]; then
				check_ld_so_argv0_feature $rootdir \
					$ld_so_candidate2

				if [ "$ld_so_argv_flag_works" == "true" ]; then
					ld_so_candidate=$ld_so_candidate2
				fi # else keep the default ld_so_candidate
			fi

			if [ "$ld_so_argv_flag_works" != "true" ]; then
				ld_so_candidate2=$SBOX_DIR/lib/libsb2/$ld_so_with_version
				if [ -f "$ld_so_candidate2" ]; then
					check_ld_so_argv0_feature $rootdir \
						$ld_so_candidate2
					if [ "$ld_so_argv_flag_works" == "true" ]; then
						ld_so_candidate=$ld_so_candidate2
					fi # else keep the default ld_so_candidate
				fi # no replacement, use the default ld.so. No --argv0
			fi
		fi
	else
		#
		# There is no dynamic linker in target rootstrap.  We
		# still check whether it is installed in the same place
		# where libsb2 for this target was found.  This is special
		# case that is normally used when building rootstraps
		# because they don't have dynamic linker installed
		# into rootstrap (yet).
		#
		# Note that we need to have symlink ld-linux.so.2 that
		# points to the actual dynamic linker since we don't
		# know its version.
		#
		ld_so_candidate2="$libsb2_dirname/ld-linux.so.2"
		if [ -L $ld_so_candidate2 ]; then
			ld_so_candidate2=`/bin/readlink -f $ld_so_candidate2`
			# check also that it has --argv0 support
			check_ld_so_argv0_feature $rootdir $ld_so_candidate2
			if [ "$ld_so_argv_flag_works" == "true" ]; then
				ld_so_candidate=$ld_so_candidate2
				ld_so_argv_flag_works="true"
			else
				ld_so_candidate=""
				ld_so_argv_flag_works="false"
			fi
		else
			ld_so_candidate=""
			ld_so_argv_flag_works="false"
		fi
	fi

	if [ -n "$SBOX_OPT_Z_NO_LD_SO_EXEC" ]; then
		ld_so_candidate=""
		ld_so_argv_flag_works="false"
	fi

	if [ -n "$ld_so_candidate" ]; then
		echo "$ld_so_path_varname = \"$ld_so_candidate\"" >>$SBOX_SESSION_DIR/exec_config.lua
		echo "$ld_so_supports_argv0_varname = $ld_so_argv_flag_works" >>$SBOX_SESSION_DIR/exec_config.lua

	else
		echo "$ld_so_path_varname = nil" >>$SBOX_SESSION_DIR/exec_config.lua
		echo "$ld_so_supports_argv0_varname = false" >>$SBOX_SESSION_DIR/exec_config.lua
	fi
}

#
# write_locale_paths_to_exec_config()
#
# Probes localization files and directories and writes
# it to exec_config.lua.
#
function write_locale_paths_to_exec_config()
{
	rootdir=$1
	generated_locale_path=$2
	locale_path_varname=$3

	#
	# Check whether $rootdir has localization files
	# in archived or extracted format.  If they are
	# in extracted format, we can use files straight
	# from $rootdir.  Otherwise we need to use extracted
	# files that were created by sb2-generate-locales and
	# placed under $locale_path.
	#
	locale_path="$rootdir/usr/lib/locale"
	if [ -d "$locale_path" ]; then
		if [ -f "$locale_path/locale-archive" ]; then
			# need to use generated files
			locale_path="$generated_locale_path"
		fi
		echo "$locale_path_varname = \"$locale_path\"" \
		    >> $SBOX_SESSION_DIR/exec_config.lua
	else
		echo "$locale_path_varname = nil" \
		    >> $SBOX_SESSION_DIR/exec_config.lua
	fi
}

# Write configuration file $SBOX_SESSION_DIR/exec_config.lua
function create_exec_config_file()
{
	cat >$SBOX_SESSION_DIR/exec_config.lua <<END
-- exec settings. Automatically generated file, do not edit.
END

	library_interface=`LD_LIBRARY_PATH=$SBOX_DIR/lib/libsb2:$LD_LIBRARY_PATH sb2-show libraryinterface`

	# 1. Exec settings for tools
	if [ "$SBOX_TOOLS_ROOT" != "" ]; then
		tools_basename=`basename $SBOX_TOOLS_ROOT`
		write_ld_library_path_replacement_to_exec_config \
			$SBOX_TOOLS_ROOT conf_tools_ld_so_library_path \
			$SBOX_DIR/lib/libsb2/tools/$tools_basename/$library_interface/libsb2.so.1 \
			$SBOX_DIR/lib/libsb2/tools/$library_interface/libsb2.so.1 \
			$SBOX_TOOLS_ROOT/usr/lib/libsb2/libsb2.so.1

		write_libsb2_and_ld_so_state_to_exec_config \
			$SBOX_TOOLS_ROOT \
			conf_tools_sb2_installed conf_tools_sbox_dir \
			conf_tools_ld_so conf_tools_ld_so_supports_argv0 \
			conf_tools_libsb2_dir

		write_locale_paths_to_exec_config \
			$SBOX_TOOLS_ROOT \
			$HOME/.scratchbox2/$tools_basename/locales \
			conf_tools_locale_path

		if [ ld_so_found != "yes" ]; then
			# ld.so from tools can not be used. Add tools' shared
			# library locations to the normal LD_LIBRARY_PATH;	
			# this is risky but the best what we can do now
			# (these extra locations must be after other locations
			# in LD_LIBRARY_PATH => ld_library_path_extras won't
			# be added to LD_LIBRARY_PATH here, but later)
			echo $ld_library_extras_from_cache |
				sed -e s:^:$rootdir:g -e "s; ;:$rootdir;g" \
				>$SBOX_SESSION_DIR/ld_library_path_extras
		fi
	else
		# SBOX_TOOLS_ROOT was empty, tools will be used from
		# host environment.
		cat <<END >>$SBOX_SESSION_DIR/exec_config.lua
conf_tools_ld_so_library_path = nil
conf_tools_sb2_installed = false
conf_tools_sbox_dir = ""
conf_tools_ld_so = nil
conf_tools_ld_so_supports_argv0 = false
conf_tools_libsb2_dir = nil
conf_tools_locale_path = nil
END
	fi

	# 2. Exec settings for rootstrap
	conf_cputransparency_has_argv0_flag="false"
	conf_cputransparency_qemu_has_env_control_flags="false"
	conf_cputransparency_qemu_has_libattr_hack_flag="false"

	if [ "$SBOX_CPUTRANSPARENCY_METHOD" == "" ]; then
		# CPU transparency method has not been set:
		# host CPU == target CPU
		if [ -n "$SBOX_CLONED_TARGET_ROOT" ]; then
			target_basename=`basename $SBOX_CLONED_TARGET_ROOT`
		else
			target_basename=`basename $SBOX_TARGET_ROOT`
		fi

		write_ld_library_path_replacement_to_exec_config \
			$SBOX_TARGET_ROOT conf_target_ld_so_library_path \
			~/.scratchbox2/libsb2/targets/$target_basename/$library_interface/libsb2.so.1 \
			~/.scratchbox2/libsb2/targets/$library_interface/libsb2.so.1 \
			$SBOX_DIR/lib/libsb2/targets/$target_basename/$library_interface/libsb2.so.1 \
			$SBOX_DIR/lib/libsb2/targets/$library_interface/libsb2.so.1 \
			$SBOX_TARGET_ROOT/usr/lib/libsb2/libsb2.so.1

		write_libsb2_and_ld_so_state_to_exec_config \
			$SBOX_TARGET_ROOT \
			conf_target_sb2_installed conf_target_sbox_dir \
			conf_target_ld_so conf_target_ld_so_supports_argv0 \
			conf_target_libsb2_dir

		write_locale_paths_to_exec_config \
			$SBOX_TARGET_ROOT \
			$HOME/.scratchbox2/$SBOX_TARGET/locales \
			conf_target_locale_path
	else
		# SBOX_CPUTRANSPARENCY_METHOD is set empty,
		# host CPU != target CPU
		cat <<END >>$SBOX_SESSION_DIR/exec_config.lua
conf_target_ld_so_library_path = nil
conf_target_sb2_installed = false
conf_target_sbox_dir = ""
conf_target_ld_so = nil
conf_target_ld_so_supports_argv0 = false
conf_target_libsb2_dir = nil
conf_target_locale_path = nil
END

		case "$SBOX_CPUTRANSPARENCY_METHOD" in	
		*qemu*)	check_qemu_features $SBOX_CPUTRANSPARENCY_METHOD
			;;
		esac
	fi

	cat <<END >>$SBOX_SESSION_DIR/exec_config.lua
conf_cputransparency_has_argv0_flag=$conf_cputransparency_has_argv0_flag
conf_cputransparency_qemu_has_env_control_flags=$conf_cputransparency_qemu_has_env_control_flags
conf_cputransparency_qemu_has_libattr_hack_flag=$conf_cputransparency_qemu_has_libattr_hack_flag
END
}

function get_SBOX_SESSION_DIR_from_file()
{
	file=$1

	SBOX_SESSION_DIR=""
	if [ ! -r "$file" ]; then
		exit_error "Failed to read '$file'"
	fi

	if grep -q "# SB2 SessionInfo:" "$file" 2>/dev/null; then
		# $file seems to be valid
		SBOX_SESSION_DIR=`sed -n -e 's/^SBOX_SESSION_DIR=//p' < $file`
		SBOX_TARGET=`sed -n -e 's/^SBOX_TARGET=//p' < $file`
	else
		exit_error "'$file' is not a valid SB2 session information file"
	fi

	if [ ! -d "$SBOX_SESSION_DIR" -o \
	     ! -f $SBOX_SESSION_DIR/.joinable-session ]; then
		exit_error "Session '$SBOX_SESSION_DIR' does not exist"
	fi
	# else the session seems to be valid.
}

# used to select a mapping mode which is distributed with sb2.
function add_map_mode()
{
	if [ -z "$SBOX_MAPMODE" ]; then
		# SBOX_MAPMODE was not set, this will be the default mode.
		# Note that more than one mapping mode can be defined only
		# when a persistent session is created (opt. -S)
		SBOX_MAPMODE=$1
	else
		if [ -z "$SB2_INTERNAL_MAPMODES" ]; then
			SB2_INTERNAL_MAPMODES="$SBOX_MAPMODE"
		fi
	fi

	SB2_INTERNAL_MAPMODES="$SB2_INTERNAL_MAPMODES $1"
	NUM_MAPMODES=`expr $NUM_MAPMODES + 1`
}

function add_external_map_mode()
{
	if [ -z "$SBOX_MAPMODE" ]; then
		# SBOX_MAPMODE was not set. Use basename of the rule file
		# as default mode name:
		SBOX_MAPMODE=`basename $1 .lua`
	fi

	SB2_EXTERNAL_RULEFILES="$SB2_EXTERNAL_RULEFILES $1"
	NUM_MAPMODES=`expr $NUM_MAPMODES + 1`
}

function initialize_new_sb2_session()
{
	# Create a new session
	if [ -n "$SBOX_WRITE_SESSION_INFO_TO_FILE" -a \
	     -f "$SBOX_WRITE_SESSION_INFO_TO_FILE" ]; then
		exit_error "File '$SBOX_WRITE_SESSION_INFO_TO_FILE' already exists."
	fi

	if [ -n "$OPT_SESSION_DIR" ]; then
		# session directory name was specified by an option
		SBOX_SESSION_DIR=$OPT_SESSION_DIR
	else
		# Create session directories
		date_and_time_now=`date +%Y%m%d-%H%M%S`
		SBOX_SESSION_DIR=`mktemp -d /tmp/sb2-$USER-$date_and_time_now.XXXXXX`
		if [ $? != 0 ]; then
			exit_error "Failed to create directory for session (problems with /tmp ?)"
		fi
	fi
	# resolve possible symlinks in SBOX_SESSION_DIR
	SBOX_SESSION_DIR=`readlink -f $SBOX_SESSION_DIR`

	mkdir -p $SBOX_SESSION_DIR
	if [ $? != 0 ]; then
		exit_error "Failed to create directory for session"
	fi
	mkdir $SBOX_SESSION_DIR/tmp
	mkdir $SBOX_SESSION_DIR/proc
	mkdir $SBOX_SESSION_DIR/rules
	mkdir $SBOX_SESSION_DIR/rev_rules

	if [ -n "$SBOX_WRITE_SESSION_INFO_TO_FILE" ]; then
		cat >$SBOX_WRITE_SESSION_INFO_TO_FILE <<END
# SB2 SessionInfo:
SBOX_SESSION_DIR=$SBOX_SESSION_DIR
SBOX_TARGET=$SBOX_TARGET
END
		touch $SBOX_SESSION_DIR/.joinable-session
	fi
}

function join_existing_session()
{
	# Join an existing session, don't create it..
	get_SBOX_SESSION_DIR_from_file "$SBOX_JOIN_SESSION_FILE"

	if [ -n "$SBOX_MAPMODE" ]; then
		# A specific mapping mode was requested by option -m,
		# see if that mode has been made available for this session
		if [ ! -f $SBOX_SESSION_DIR/rules/$SBOX_MAPMODE.lua ]
		then
			exit_error "'$SBOX_MAPMODE' is not a valid mode for this session"
		fi
		# Mode is valid, most probably something else than the
		# default mode for this session. Set an environment variable
		# which will overide the value from the config file.
		export SBOX_SESSION_MODE=$SBOX_MAPMODE
	fi
	if [ -z "$SBOX_TARGET" ]; then
		exit_error "Failed to read SBOX_TARGET from $SBOX_JOIN_SESSION_FILE"
	fi
	OPT_CLONE_TARGET_ROOT="n"
	OPT_CLONE_TARGET_ROOT_FROM=""
}

# create destination for /sb2/wrappers for this session
function link_wrappers_for_mapmode()
{
	w_mode=$1

	if [ -f $SBOX_DIR/share/scratchbox2/modeconf/sb2rc.$w_mode ]; then
		# Get list of wrappers:
		SBOX_WRAPPERS=""
		. $SBOX_DIR/share/scratchbox2/modeconf/sb2rc.$w_mode wrapper_list
		if [ "$SBOX_WRAPPERS" != '' ]; then
			mkdir $SBOX_SESSION_DIR/wrappers.$w_mode

			if [ "$SBOX_WRAPPERS" == 'ALL' ]; then
				ln -s $SBOX_DIR/share/scratchbox2/wrappers/* \
					$SBOX_SESSION_DIR/wrappers.$w_mode
			else
				for ammw in $SBOX_WRAPPERS; do
					if [ -f $SBOX_DIR/share/scratchbox2/wrappers/$ammw ]; then
						ln -s $SBOX_DIR/share/scratchbox2/wrappers/$ammw \
							$SBOX_SESSION_DIR/wrappers.$w_mode
					else
						exit_error "There is no wrapper for $ammw"
					fi
				done
			fi
		fi
	fi
}

function write_configfiles_and_rules_for_new_session()
{
	# creating a new session..
	ln -s $SBOX_LUA_SCRIPTS $SBOX_SESSION_DIR/lua_scripts

	# Create rulefiles and set up wrappers
	if [ -n "$SB2_INTERNAL_MAPMODES" ]; then
		for amm in $SB2_INTERNAL_MAPMODES; do
			ifiles=`ls $SBOX_SESSION_DIR/lua_scripts/pathmaps/$amm/*.lua`
			write_rules_to_session_dir \
				$SBOX_SESSION_DIR/rules/$amm.lua $amm $ifiles

			link_wrappers_for_mapmode $amm
		done
	fi

	if [ -n "$SB2_EXTERNAL_RULEFILES" ]; then
		for ammf in $SB2_EXTERNAL_RULEFILES; do
			amm=`basename $ammf .lua`
			write_rules_to_session_dir \
				$SBOX_SESSION_DIR/rules/$amm.lua $amm $ammf

			# FIXME: Currently it is not possible to specify
			# wrappers with option -M (maybe another option
			# should be added to fix that?)
		done
	fi

	# use a hard link for the rule file name, it is better (faster) than
	# a symlink. "Default.lua" will be loaded, if SBOX_SESSION_MODE is
	# unset (as it is usually)
	ln $SBOX_SESSION_DIR/rules/$SBOX_MAPMODE.lua \
		$SBOX_SESSION_DIR/rules/Default.lua

	create_exec_config_file
	create_common_sb2_conf_file_for_session
	create_gcc_conf_file_for_session

	# Copy intial contents of /var/run from the rootstrap:
	mkdir $SBOX_SESSION_DIR/var
	if [ -d $SBOX_TARGET_ROOT/var ]; then
		(cd $SBOX_TARGET_ROOT/var; find run -depth -print |
			cpio -pamd $SBOX_SESSION_DIR/var 2>/dev/null)
	fi
}

function delete_old_sb2_session()
{
	# Delete a session
	get_SBOX_SESSION_DIR_from_file "$SBOX_DELETE_SESSION_FILE"

	# now we "know" that $SBOX_SESSION_DIR is a directory,
	# but double-checking doesn't hurt before rm -rf..
	if [ -d "$SBOX_SESSION_DIR" ]; then
		rm -rf $SBOX_SESSION_DIR
	fi

	rm "$SBOX_DELETE_SESSION_FILE"
}

my_path=$_
if [ $(basename $my_path) != $(basename $0) ]; then
	my_path=$0
	if [ $(basename $my_path) = $my_path ]; then
		my_path=$(which $my_path)
	fi
fi

SBOX_MAPMODE=""
NUM_MAPMODES=0
SB2_INTERNAL_MAPMODES=""

SBOX_DIR=$(readlink -f $(dirname $(readlink -f $my_path))/..)
SBOX_WORKDIR=$(readlink -f $PWD)
SBOX_SESSION_PERM=""
SBOX_CREATE_REVERSE_RULES="y"
SBOX_MODE_SPECIFIC_OPTIONS=""
OPT_CLONE_TARGET_ROOT="n"
OPT_CLONE_TARGET_ROOT_FROM=""
OPT_SESSION_DIR=""
SBOX_FORCED_TOOLS_ROOT=""

while getopts vdht:em:s:L:Q:M:ZrRS:J:D:W:O:cC:T: foo
do
	case $foo in
	(v) version; exit 0;;
	(d) export SBOX_MAPPING_DEBUG=1
	    export SBOX_MAPPING_LOGLEVEL=debug ;;
	(L) export SBOX_MAPPING_DEBUG=1
	    export SBOX_MAPPING_LOGLEVEL=$OPTARG ;;
	(Q) SBOX_EMULATE_SB1_BUGS=$OPTARG ;;
	(h) usage ;;
	(t) SBOX_TARGET=$OPTARG ;;
	(e) add_map_mode emulate ;;
	(m) add_map_mode $OPTARG ;;
	(M) add_external_map_mode $OPTARG ;;
	(s) SBOX_LUA_SCRIPTS=$OPTARG;;
	(Z) SBOX_OPT_Z_NO_LD_SO_EXEC="y";;
	(r) SBOX_CREATE_REVERSE_RULES="n";;
	(R) SBOX_SESSION_PERM="root";;
	(S) SBOX_WRITE_SESSION_INFO_TO_FILE=$OPTARG ;;
	(J) SBOX_JOIN_SESSION_FILE=$OPTARG ;;
	(D) SBOX_DELETE_SESSION_FILE=$OPTARG ;;
	(W) OPT_SESSION_DIR=$OPTARG ;;
	(O) SBOX_MODE_SPECIFIC_OPTIONS=$OPTARG ;;
	(c) OPT_CLONE_TARGET_ROOT="y" ;;
	(C) OPT_CLONE_TARGET_ROOT_FROM=$OPTARG ;;
	(T) SBOX_FORCED_TOOLS_ROOT=$OPTARG ;;
	(*) usage ;;
	esac
done
shift $(($OPTIND - 1))

if [ -n "$SBOX_SESSION_DIR" -a -f "$SBOX_SESSION_DIR/rules/Default.lua" ]; then
	# already inside an sb2 session; ignore all options and just exec the command.
	echo "WARNING: recursive calls to sb2 are not supported (session already exists)"
	echo "WARNING: going to execute '$*' in this session"
	exec $*
fi

#----------- Check parameters

if [ "$SBOX_MAPPING_DEBUG" == "1" ]; then
	# check that loglevel is valid
	case $SBOX_MAPPING_LOGLEVEL in
	(error|warning|notice|info|debug|noise|noise2|noise3)	;; # OK
	(*) usage ;;
	esac
else
	# default logging level
	export SBOX_MAPPING_LOGLEVEL=warning
fi

if [ -z "$SBOX_WRITE_SESSION_INFO_TO_FILE" ]; then
	# Multiple -m and/or -M options are allowed only
	# when creating a parsistent session
	if [ $NUM_MAPMODES -gt 1 ]; then
		exit_error "Only one of -e, -m or -M is allowed"
	fi
fi

# read commands to execute from stdin - not yet implemented
if [ "$1" = "-" ] ; then
	STDIN=true
fi

# if SBOX_SESSION_PERM is set, export it. It may enable special permissions
# in some mapping modes (e.g. see the "emulate" mode)
if [ -n "$SBOX_SESSION_PERM" ]; then
	export SBOX_SESSION_PERM
	SBOX_FAKEROOT_PREFIX="fakeroot"
fi

if [ -n "$SBOX_FORCED_TOOLS_ROOT" ]; then
	if [ ! -d "$SBOX_FORCED_TOOLS_ROOT" ]; then
		exit_error "Directory $SBOX_FORCED_TOOLS_ROOT does not exist"
	fi
fi

if [ -z "$SBOX_JOIN_SESSION_FILE" ]; then
	# -J was not used
	set_and_check_SBOX_TARGET
	if [ -n "$OPT_SESSION_DIR" ]; then
		case "$OPT_SESSION_DIR" in
		(/*)	;; # OK, absolute
		(*)	exit_error "Option '-W' requires an absolute path"
		esac
		if [ -e "$OPT_SESSION_DIR" ]; then
			exit_error "Option '-W': $OPT_SESSION_DIR exists"
		fi
	fi
else
	# With -J, $SBOX_TARGET *must* come from the session file.
	if [ -n "$SBOX_TARGET" ]; then
		exit_error "Option '-t' can't be used with option '-J'"
	fi
	if [ -n "$OPT_SESSION_DIR" ]; then
		exit_error "Option '-W' can't be used with option '-J'"
	fi
fi

#----------- End of parameter checks

if [ -n "$SBOX_DELETE_SESSION_FILE" ]; then
	delete_old_sb2_session
	exit 0
fi

if [ -n "$SBOX_JOIN_SESSION_FILE" ]; then
	join_existing_session
	set_and_check_SBOX_TARGET
else
	initialize_new_sb2_session
fi

# SBOX_SESSION_DIR needs to be passed in environment variable, always.
export SBOX_SESSION_DIR

sboxify_environment

if [ -z "$SB2_INTERNAL_MAPMODES" -a -z "$SB2_EXTERNAL_RULEFILES" ]; then
	# mapping mode was not specified by an option, SBOX_MAPMODE has been
	# set from the config file by sboxify_environment
	SB2_INTERNAL_MAPMODES=$SBOX_MAPMODE
fi

if [ -z "$SBOX_JOIN_SESSION_FILE" ]; then
	write_configfiles_and_rules_for_new_session
fi

# set the initial binary name for the mapping engine
export __SB2_BINARYNAME="bash"

if [ -n "$SBOX_TOOLS_ROOT" ]; then
	SHELL=$SBOX_TOOLS_ROOT/bin/bash
else
	SHELL=/bin/bash
fi

# Final addition to LD_LIBRARY_PATH, if needed
if [ -f $SBOX_SESSION_DIR/ld_library_path_extras ]; then
	LD_LIBRARY_PATH=$LD_LIBRARY_PATH:`cat $SBOX_SESSION_DIR/ld_library_path_extras`
fi

# ------------
# Export variables that need to be available in environment;
# don't export anything unnecessary!

export DEB_BUILD_ARCH
export DEB_BUILD_ARCH_CPU
export DEB_BUILD_ARCH_ABI
export DEB_BUILD_GNU_CPU
export DEB_BUILD_GNU_TYPE
export DEB_BUILD_GNU_SYSTEM

export DEB_HOST_ARCH
export DEB_HOST_ARCH_OS
export DEB_HOST_ARCH_CPU

export DEB_HOST_GNU_CPU
export DEB_HOST_GNU_TYPE
export DEB_HOST_GNU_SYSTEM

export LD_LIBRARY_PATH

# ------------
# Now everything is ready, programs can be executed in SB2'ed environment.
# Make automatically generated rules, if needed:
if [ -z "$SBOX_JOIN_SESSION_FILE" ]; then
	#
	# Only generate argvmods rules when we are not joining
	# to session.
	#
	create_argvmods_rules

	# if needed, create path mapping rules for toolchain components.
	# this can only be done after "create_argvmods_rules" has been executed.
	if [ -n "CREATE_ARGVMODS_USR_BIN_RULES" ]
	then
		create_argvmods_usr_bin_rules "$CREATE_ARGVMODS_USR_BIN_RULES"
	fi

	#
	# Create reverse mapping rules before starting the
	# actual command (or shell).
	#
	if [ "$SBOX_CREATE_REVERSE_RULES" == "y" ]; then
		create_reverse_rules
	else
		echo "-- Reverse rules disabled by command line option -r" \
			>$SBOX_SESSION_DIR/rev_rules.note
	fi
fi

#  Initialize logs..
if [ $# -gt 0 -o "$STDIN" = true ] ; then
	initialize_sb_logging $(echo $1 | sed -e 's/\//_/g' -e 's/^\.//') "$args"
else
	initialize_sb_logging sb2
fi

# ------------ cleanup:
# Unset variables which used to be passed in environment,
# but have been moved to sb2-session.conf.
unset SBOX_MAPMODE
unset SBOX_TARGET_ROOT
unset SBOX_CLONED_TARGET_ROOT
unset SBOX_TOOLS_ROOT

# ------------

if [ $# -gt 0 -o "$STDIN" = true ]; then
	binary="$1"
	shift 1
	args="$@"
	exec $SBOX_FAKEROOT_PREFIX sb2-monitor -L $SBOX_LIBSB2 -x $SBOX_DIR/share/scratchbox2/scripts/sb2-exitreport \
		-- $SHELL -c "$binary $args"
else
	exec $SBOX_FAKEROOT_PREFIX sb2-monitor -L $SBOX_LIBSB2 -x $SBOX_DIR/share/scratchbox2/scripts/sb2-exitreport \
		-- $SHELL --noprofile --norc
fi