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#!/bin/sh
#
# Xdummy: an LD_PRELOAD hack to run a stock Xorg(1) or XFree86(1) server
# with the "dummy" video driver to make it avoid Linux VT switching, etc.
#
# Run "Xdummy -help" for more info.
#
xserver=""
geom=""
geom=""
install=""
uninstall=""
root=""
debug=""
strace=""
runit=1
prconf=""
noconf=""

PATH=$PATH:/bin:/usr/bin
export PATH

program=`basename "$0"`

help () {
	${PAGER:-more} << END

$program: a hack to run a stock Xorg(1) or XFree86(1) X server with the
"dummy" video driver such that it AVOIDS the Linux VT switching, keyboard
mouse conflicts, etc associated with normal use of "dummy".  

In other words, try to make Xorg/XFree86 with the Device "dummy" driver
act more like Xvfb(1).

To achieve this, while running the real Xserver $program intercepts system
and library calls via the LD_PRELOAD method and modifies the behavior
to make it work correctly (i.e. avoid the VT stuff).  LD_PRELOAD tricks
are usually "clever hacks" and so might not work in all situations or
break when something changes.

The primary motivation for the Xdummy script is to provide a virtual X
server for x11vnc but with more features than Xvfb (or Xvnc), however
it could be used for other reasons (e.g. better automated testing than
with Xvfb).  A nice by-product is the dummy server supports RANDR dynamic
resizing while Xvfb does not.  So, for example x11vnc+Xdummy terminal
services are a little better than x11vnc+Xvfb.

This program does not need to be run as root as of 12/2009.  However,
if there are problems for certain situations it may perform better
if run as root (-root option.)

Also, gcc/cc is required to compile the LD_PRELOAD shared object.
See -install and -uninstall described below.


Your Linux distribution may not install the dummy driver by default, e.g:

    /usr/lib/xorg/modules/drivers/dummy_drv.so

some have it in a package named xserver-xorg-video-dummy you need
to install.


Usage:

	$program <${program}-args> [--] <Xserver-args>


Examples:

	$program :1

	$program -debug -tmpdir ~/mytmp :1

	$program -install

startx example:

	startx -e bash -- $program :2 -depth 16

	(if startx needs to be run as root, you can su(1) to a normal
	user in the bash shell and then launch ~/.xinitrc or ~/.xsession,
	gnome-session, startkde, startxfce4, etc.)

xdm example:

	xdm -config /usr/local/dummy/xdm-config -nodaemon

	where the xdm-config file has line:

	     DisplayManager.servers:         /usr/local/dummy/Xservers

	and /usr/local/dummy/Xservers has lines:

	     :1 local /usr/local/dummy/Xdummy :1 -debug
	     :2 local /usr/local/dummy/Xdummy :2 -debug

gdm/kdm example:

	TBD.

Root permission and x11vnc:

	Update: as of 12/2009 this program no longer must be run as root.

	However, in some circumstances program may need to be run as
	root.  If so, one could run x11vnc as root with -unixpw (it
	switches to the user that logs in) and that may be OK, some
	other ideas:

	- add this to sudo via visudo:

		ALL ALL = NOPASSWD: /usr/local/bin/Xdummy

	- use this little suid wrapper:
/* 
 * xdummy.c
 *
   cc -o ./xdummy xdummy.c
   sudo cp ./xdummy /usr/local/bin/xdummy
   sudo chown root:root /usr/local/bin/xdummy
   sudo chmod u+s /usr/local/bin/xdummy
 *
 */
#include <unistd.h>
#include <stdlib.h>
#include <sys/types.h>
#include <stdio.h>

int main (int argc, char *argv[]) {
	extern char **environ;
	char str[100];
	sprintf(str, "XDUMMY_UID=%d", (int) getuid());
	putenv(str);
	setuid(0);  
	setgid(0);
	execv("/usr/local/bin/Xdummy", argv); 
	exit(1);
	return 1;
}


Options:

    ${program}-args:

	-install	Compile the LD_PRELOAD shared object and install it
			next to the $program script file as: $0.so

			When that file exists it is used as the LD_PRELOAD
			shared object without recompiling.  Otherwise,
			each time $program is run the LD_PRELOAD shared
			object is compiled as a file in /tmp (or -tmpdir).

	-uninstall	Remove the file: $0.so
			The LD_PRELOAD shared object will then be compiled
			each time this program is run.

	Note: the X server is not started under -install or -uninstall.


	:N		The DISPLAY can be the first $program argument.
			It is passed to the real X server.  This is to
			aid use with startx(1), xinit(1), xdm(1), etc.
			If one is not provided it tries to choose one
			automatically.

	-geom geom1[,geom2...]  Take the geometry (e.g. 1024x768) or
			list of geometries and insert them into the
			Screen section of the tweaked X server 
			config file.  Use this to have a smaller geometry
			than the one in the system config file.

	-tmpdir dir	Specify a temporary directory, owned by you and
			only writable by you.  This is used in place of
			/tmp/Xdummy.\$USER/..  to place the $program.so
			shared object, tweaked config files, etc.

	-nonroot	Run in non-root mode (working 12/2009, now default)

	-root		Run as root (may still be needed in some
			environments.)

	-nosudo		Do not try to use sudo(1) when re-running as root,
			use su(1) instead.

	-xserver path	Specify the path to the Xserver to use.  Default
			is to try "Xorg" first and then "XFree86".  If
			those are not in \$PATH, use these locations:
				/usr/X11R6/bin/Xorg
				/usr/X11R6/bin/XFree86

	-n		Do not run the command to start the X server,
			just show the command that $program would run.
			The LD_PRELOAD shared object will be built,
			if needed.

	-prconf		Print, to stdout, the tweaked Xorg or XFree86
			config file (-config and -xf86config server
			options, respectively).  The Xserver is not
			started.

	-noconf		Do not tweak the Xorg or XFree86 config file
			(system or server command line) at all.  It is
			up to you to make sure it is a working config
			file (e.g. "dummy" driver, etc).  Perhaps you
			want to use a file based on -prconf output.

	-debug		Extra debugging output.

	-strace		strace(1) the Xserver process (for troubleshooting).

	-h, -help	Print out this help.


    Xserver-args:

	Most of the Xorg and XFree86 options will work.  Important ones
	that may be supplied if missing:

	:N		X Display number for server to use.

	vtNN		Linux virtual terminal (VT) to use (a VT is currently
			still used, just not switched to and from).

	-config file		Driver "dummy" tweaked config file, a
	-xf86config file	number of settings are tweaked besides Driver.

	If -config/-xf86config is not given, the system one is used.
	Any settings in the config file that are not consistent with
	"dummy" mode will be overwritten (unless -noconf is used).

Notes:

    The Xorg/XFree86 "dummy" driver is currently undocumented.  It works
    well in this mode, but it is evidently not intended for end-users.
    So it could be removed or broken at any time.

    If the display Xserver-arg (e.g. :1) is not given, or ":" or ":9999"
    is given that indicates $program should try to find a free one.

    If the display virtual terminal, VT, (e.g. vt9) is not given that
    indicates $program should try to find a free one (or guess a high one). 
    
    This program is not completely secure WRT files in /tmp (but it tries
    to a good degree).  Better is to use the -tmpdir option to supply a
    directory only writable by you.  Even better is to get rid of users
    on the local machine you do not trust :-)

END
}

warn() {
	echo "$*" 1>&2
}

if [ "X$XDUMMY_SET_XV" != "X" ]; then
	set -xv
fi

if [ "X$XDUMMY_UID" = "X" ]; then
	XDUMMY_UID=`id -u`
	export XDUMMY_UID
fi
if [ "X$XDUMMY_UID" = "X0" ]; then
	if [ "X$SUDO_UID" != "X" ]; then
		XDUMMY_UID=$SUDO_UID
		export XDUMMY_UID
	fi
fi

# check if root=1 first:
#
if [ "X$XDUMMY_RUN_AS_ROOT" = "X1" ]; then
	root=1
fi
for arg in $*
do
	if [ "X$arg" = "X-nonroot" ]; then
		root=""
	elif [ "X$arg" = "X-root" ]; then
		root=1
	fi
done

# See if it really needs to be run as root:
#
if [ "X$XDUMMY_SU_EXEC" = "X" -a "X$root" = "X1" -a "X`id -u`" != "X0"  ]; then
	# this is to prevent infinite loop in case su/sudo doesn't work:
	XDUMMY_SU_EXEC=1
	export XDUMMY_SU_EXEC

	dosu=1
	nosudo=""

	for arg in $*
	do
		if [ "X$arg" = "X-nonroot" ]; then
			dosu=""
		elif [ "X$arg" = "X-nosudo" ]; then
			nosudo="1"
		elif [ "X$arg" = "X-help" ]; then
			dosu=""
		elif [ "X$arg" = "X-h" ]; then
			dosu=""
		elif [ "X$arg" = "X-install" ]; then
			dosu=""
		elif [ "X$arg" = "X-uninstall" ]; then
			dosu=""
		elif [ "X$arg" = "X-n" ]; then
			dosu=""
		elif [ "X$arg" = "X-prconf" ]; then
			dosu=""
		elif [ "X$arg" = "X--" ]; then
			break
		fi
	done
	if [ $dosu ]; then
		# we need to restart it with su/sudo:
		if type sudo > /dev/null 2>&1; then
			:
		else
			nosudo=1
		fi
		if [ "X$nosudo" = "X" ]; then
			warn "$program: supply the sudo password to restart as root:"
			if [ "X$XDUMMY_UID" != "X" ]; then
				exec sudo $0 -uid $XDUMMY_UID "$@"
			else
				exec sudo $0 "$@"
			fi
		else
			warn "$program: supply the root password to restart as root:"
			if [ "X$XDUMMY_UID" != "X" ]; then
				exec su -c "$0 -uid $XDUMMY_UID $*"
			else
				exec su -c "$0 $*"
			fi
		fi
		exit
	fi
fi

# This will hold the X display, e.g. :20
#
disp=""
args=""

# Process Xdummy args:
#
while [ "X$1" != "X" ]
do
    case $1 in 
	":"*)	disp=$1
                ;;
	"-install") install=1
                ;;
	"-uninstall") uninstall=1
                ;;
	"-n")  runit=""
                ;;
	"-no") runit=""
                ;;
	"-norun") runit=""
                ;;
	"-prconf") prconf=1
                ;;
	"-noconf") noconf=1
                ;;
	"-nonroot") root=""
                ;;
	"-root")    root=1
                ;;
	"-nosudo") nosudo=1
                ;;
	"-xserver") xserver="$2"; shift
                ;;
	"-uid") XDUMMY_UID="$2"; shift
		export XDUMMY_UID
                ;;
	"-geom"*) geom="$2"; shift
                ;;
	"-depth") depth="$2"; shift
                ;;
	"-tmpdir") XDUMMY_TMPDIR="$2"; shift
                ;;
	"-debug") debug=1
                ;;
	"-nodebug") debug=""
                ;;
	"-strace") strace=1
                ;;
	"-h"*)	help; exit 0
                ;;
	"--")	shift; break
                ;;
	*)	args="$args $1"
                ;;
    esac
    shift
done

# Try to get a username for use in our tmp directory, etc.
#
user=""
if [ X`id -u` = "X0"  ]; then
	user=root	# this will also be used below for id=0
elif [ "X$USER" != "X" ]; then
	user=$USER
elif [ "X$LOGNAME" != "X" ]; then
	user=$LOGNAME
fi

# Keep trying...
#
if [ "X$user" = "X" ]; then
	user=`whoami 2>/dev/null`
fi
if [ "X$user" = "X" ]; then
	user=`basename "$HOME"`
fi
if [ "X$user" = "X" -o "X$user" = "X." ]; then
	user="u$$"
fi

if [ "X$debug" = "X1" -a "X$runit" != "X" ]; then
	echo ""
	echo "/usr/bin/env:"
	env | egrep -v '^(LS_COLORS|TERMCAP)' | sort
	echo ""
fi

# Function to compile the LD_PRELOAD shared object:
#
make_so() {

	# extract code embedded in this script into a tmp C file: 
	n1=`grep -n '^#code_begin' $0 | head -1 | awk -F: '{print $1}'`
	n2=`grep -n '^#code_end'   $0 | head -1 | awk -F: '{print $1}'`
	n1=`expr $n1 + 1`
	dn=`expr $n2 - $n1`

	tmp=$tdir/Xdummy.$$.c
	rm -f $tmp
	if [ -e $tmp -o -h $tmp ]; then
		warn "$tmp still exists."
		exit 1
	fi
	tail -n +$n1 $0 | head -n $dn > $tmp

	# compile it to Xdummy.so:
	rm -f $SO
	touch $SO
	if [ ! -f $SO ]; then
		SO=$tdir/Xdummy.$user.so
		warn "warning switching LD_PRELOAD shared object to: $SO"
	fi
	rm -f $SO

	# we assume gcc:
	cc -shared -fPIC -o $SO $tmp
	rc=$?
	rm -f $tmp
	if [ $rc != 0 ]; then
		warn "$program: cannot build $SO"
		exit 1
	fi
	if [ "X$debug" != "X" -o "X$install" != "X" ]; then
		warn "$program: created  $SO"
		ls -l "$SO"
	fi
}

# Set tdir to tmp dir for make_so():
if [ "X$XDUMMY_TMPDIR" != "X" ]; then
	tdir=$XDUMMY_TMPDIR
	mkdir -p $tdir
else
	tdir="/tmp"
fi

# Handle -install/-uninstall case:
SO=$0.so
if [ "X$install" != "X" -o "X$uninstall" != "X" ]; then
	if [ -e $SO -o -h $SO ]; then
		warn "$program: removing $SO"
	fi
	rm -f $SO
	if [ -e $SO -o -h $SO ]; then
		warn "warning: $SO still exists."
		exit 1
	fi
	if [ $install ]; then
		make_so
		if [ ! -f $SO ]; then
			exit 1
		fi
	fi
	exit 0
fi

# We need a tmp directory for the .so, tweaked config file, and for
# redirecting filenames we cannot create (under -nonroot)
#
tack=""
if [ "X$XDUMMY_TMPDIR" = "X" ]; then
	XDUMMY_TMPDIR="/tmp/Xdummy.$user"

	# try to tack on a unique subdir (display number or pid)
	# to allow multiple instances
	#
	if [ "X$disp" != "X" ]; then
		t0=$disp
	else
		t0=$1
	fi
	tack=`echo "$t0" | sed -e 's/^.*://'`
	if echo "$tack" | grep '^[0-9][0-9]*$' > /dev/null; then
		:
	else
		tack=$$
	fi
	if [ "X$tack" != "X" ]; then
		XDUMMY_TMPDIR="$XDUMMY_TMPDIR/$tack"
	fi
fi

tmp=$XDUMMY_TMPDIR
if echo "$tmp" | grep '^/tmp' > /dev/null; then
	if [ "X$tmp" != "X/tmp" -a "X$tmp" != "X/tmp/" ]; then
		# clean this subdir of /tmp out, otherwise leave it...
		rm -rf $XDUMMY_TMPDIR
		if [ -e $XDUMMY_TMPDIR ]; then
			warn "$XDUMMY_TMPDIR still exists"
			exit 1
		fi
	fi
fi

mkdir -p $XDUMMY_TMPDIR
chmod 700 $XDUMMY_TMPDIR
if [ "X$tack" != "X" ]; then
	chmod 700 `dirname "$XDUMMY_TMPDIR"` 2>/dev/null
fi

# See if we can write something there:
#
tfile="$XDUMMY_TMPDIR/test.file"
touch $tfile
if [ ! -f $tfile ]; then
	XDUMMY_TMPDIR="/tmp/Xdummy.$$.$USER"
	warn "warning: setting tmpdir to $XDUMMY_TMPDIR ..."
	rm -rf $XDUMMY_TMPDIR || exit 1
	mkdir -p $XDUMMY_TMPDIR || exit 1
fi
rm -f $tfile

export XDUMMY_TMPDIR

# Compile the LD_PRELOAD shared object if needed (needs XDUMMY_TMPDIR)
#
if [ ! -f $SO ]; then
	SO="$XDUMMY_TMPDIR/Xdummy.so"
	make_so
fi

# Decide which X server to use:
#
if [ "X$xserver" = "X" ]; then
	if type Xorg >/dev/null 2>&1; then
		xserver="Xorg"
	elif type XFree86 >/dev/null 2>&1; then
		xserver="XFree86"
	elif -x /usr/bin/Xorg; then
		xserver="/usr/bin/Xorg"
	elif -x /usr/X11R6/bin/Xorg; then
		xserver="/usr/X11R6/bin/Xorg"
	elif -x /usr/X11R6/bin/XFree86; then
		xserver="/usr/X11R6/bin/XFree86"
	fi
	if [ "X$xserver" = "X" ]; then
		# just let it fail below.
		xserver="/usr/bin/Xorg"
		warn "$program: cannot locate a stock Xserver... assuming $xserver"
	fi
fi

# See if the binary is suid or not readable under -nonroot mode:
#
if [ "X$BASH_VERSION" != "X" ]; then
	xserver_path=`type -p $xserver 2>/dev/null`
else
	xserver_path=`type $xserver 2>/dev/null | awk '{print $NF}'`
fi
if [ -e "$xserver_path" -a "X$root" = "X" -a "X$runit" != "X" ]; then
	if [ ! -r $xserver_path -o -u $xserver_path -o -g $xserver_path ]; then
		# XXX not quite correct with rm -rf $XDUMMY_TMPDIR ...
		# we keep on a filesystem we know root can write to.
		base=`basename "$xserver_path"`
		new="/tmp/$base.$user.bin"
		if [ -e $new ]; then
			snew=`ls -l $new          | awk '{print $5}' | grep '^[0-9][0-9]*$'`
			sold=`ls -l $xserver_path | awk '{print $5}' | grep '^[0-9][0-9]*$'`
			if [ "X$snew" != "X" -a "X$sold" != "X" -a "X$sold" != "X$snew" ]; then
				warn "removing different sized copy:"
				ls -l $new $xserver_path
				rm -f $new
			fi
		fi
		if [ ! -e $new -o ! -s $new ]; then
			rm -f $new
			touch $new || exit 1
			chmod 700 $new || exit 1
			if [ ! -r $xserver_path ]; then
				warn ""
				warn "NEED TO COPY UNREADABLE $xserver_path to $new as root:"
				warn ""
				ls -l $xserver_path 1>&2
				warn ""
				warn "This only needs to be done once:"
				warn "    cat $xserver_path > $new"
				warn ""
				nos=$nosudo
				if type sudo > /dev/null 2>&1; then
					:
				else
					nos=1
				fi
				if [ "X$nos" = "X1" ]; then
					warn "Please supply root passwd to 'su -c'"
					su -c "cat $xserver_path > $new"
				else
					warn "Please supply the sudo passwd if asked:"
					sudo /bin/sh -c "cat $xserver_path > $new"
				fi
			else
				warn ""
				warn "COPYING SETUID $xserver_path to $new"
				warn ""
				ls -l $xserver_path 1>&2
				warn ""
				cat $xserver_path > $new
			fi
			ls -l $new
			if [ -s $new ]; then
				:
			else
				rm -f $new
				ls -l $new
				exit 1
			fi
			warn ""
			warn "Please restart Xdummy now."
			exit 0
		elif [ ! -O $new ]; then
			warn "file \"$new\" not owned by us!"
			ls -l $new
			exit 1
		fi
		xserver=$new
	fi 
fi

# Work out display:
#
if [ "X$disp" != "X" ]; then
	:
elif [ "X$1" != "X" ]; then
	if echo "$1" | grep '^:[0-9]' > /dev/null; then
		disp=$1
		shift
	elif [ "X$1" = "X:" ]; then
		# ":" means for us to find one.
		shift
	fi
fi
if [ "X$disp" = "X" -o "X$disp" = "X:" ]; then
	# try to find an open display port:
	# (tcp outdated...)
	ports=`netstat -ant | grep LISTEN | awk '{print $4}' | sed -e 's/^.*://'`
	n=0
	while [ $n -le 20 ]
	do
		port=`printf "60%02d" $n`
		if echo "$ports" | grep "^${port}\$" > /dev/null; then
			:
		else
			disp=":$n"
			warn "$program: auto-selected DISPLAY $disp"
			break	
		fi
		n=`expr $n + 1`
	done
fi

# Work out which vt to use, try to find/guess an open one if necessary.
#
vt=""
for arg in $*
do
	if echo "$arg" | grep '^vt' > /dev/null; then
		vt=$arg
		break
	fi
done
if [ "X$vt" = "X" ]; then
	if [ "X$user" = "Xroot" ]; then
		# root can user fuser(1) to see if it is in use:
		if type fuser >/dev/null 2>&1; then
			# try /dev/tty17 thru /dev/tty32
			n=17
			while [ $n -le 32 ]
			do
				dev="/dev/tty$n"
				if fuser $dev >/dev/null 2>&1; then
					:
				else
					vt="vt$n"
					warn "$program: auto-selected VT $vt => $dev"
					break
				fi
				n=`expr $n + 1`
			done
		fi
	fi
	if [ "X$vt" = "X" ]; then
		# take a wild guess...
		vt=vt16
		warn "$program: selected fallback VT $vt"
	fi
else
	vt=""
fi

# Decide flavor of Xserver:
#
stype=`basename "$xserver"`
if echo "$stype" | grep -i xorg > /dev/null; then
	stype=xorg
else
	stype=xfree86
fi

# Work out config file and tweak it.
#
next=""
config=""
got_config=""
for arg in $*
do
	if [ $next ]; then
		config="$arg"
		got_config=1
		break
	fi
	if [ "X$arg" = "X-xf86config" ]; then
		if [ "X$stype" = "X" ]; then
			stype="xfree86"
		fi
		next=1
	elif [ "X$arg" = "X-config" ]; then
		if [ "X$stype" = "X" ]; then
			stype="xorg"
		fi
		next=1
	fi
done

tweak_config() {
    in="$1"
    config2="$XDUMMY_TMPDIR/xdummy_modified_xconfig.conf"
    if [ "X$disp" != "X" ]; then
    	d=`echo "$disp" | sed -e 's,/,,g' -e 's/:/_/g'`
	config2="$config2$d"
    fi
    
    # perl script to tweak the config file... add/delete options, etc.
    #
    env XDUMMY_GEOM=$geom \
        XDUMMY_DEPTH=$depth \
        perl > $config2 < $in -e '
    $n = 0;
    $geom  = $ENV{XDUMMY_GEOM};
    $depth = $ENV{XDUMMY_DEPTH};
    $videoram = "24000";
    $HorizSync   = "30.0 - 130.0";
    $VertRefresh = "50.0 - 250.0";
    if ($geom ne "") {
    	my $tmp = "";
	foreach $g (split(/,/, $geom)) {
		$tmp .= "\"$g\" ";
	}
	$tmp =~ s/\s*$//;
	$geom = $tmp;
    }
    while (<>) {
	$n++;
	if (/^\s*#/) {
		# pass comments straight thru
		print;
		next;
	}
	if (/^\s*Section\s+(\S+)/i) {
		# start of Section
		$sect = $1;
		$sect =~ s/\W//g;
		$sect =~ y/A-Z/a-z/;
		$sects{$sect} = 1;
		print;
		next;
	}
	if (/^\s*EndSection/i) {
		# end of Section
		if ($sect eq "serverflags") {
			if (!$got_DontVTSwitch) {
				print "  ##Xdummy:##\n";
				print "  Option \"DontVTSwitch\" \"true\"\n";
			}
			if (!$got_AllowMouseOpenFail) {
				print "  ##Xdummy:##\n";
				print "  Option \"AllowMouseOpenFail\" \"true\"\n";
			}
			if (!$got_PciForceNone) {
				print "  ##Xdummy:##\n";
				print "  Option \"PciForceNone\" \"true\"\n";
			}
		} elsif ($sect eq "device") {
			if (!$got_Driver) {
				print "  ##Xdummy:##\n";
				print "  Driver \"dummy\"\n";
			}
			if (!$got_VideoRam) {
				print "  ##Xdummy:##\n";
				print "  VideoRam $videoram\n";
			}
		} elsif ($sect eq "screen") {
			if ($depth ne "" && !got_DefaultDepth) {
				print "  ##Xdummy:##\n";
				print "  DefaultDepth $depth\n";
			}
			if ($got_Monitor eq "") {
				print "  ##Xdummy:##\n";
				print "  Monitor \"Monitor0\"\n";
			}
		} elsif ($sect eq "monitor") {
			if (!got_HorizSync) {
				print "  ##Xdummy:##\n";
				print "  HorizSync   $HorizSync\n";
			}
			if (!got_VertRefresh) {
				print "  ##Xdummy:##\n";
				print "  VertRefresh $VertRefresh\n";
			}
		}
		$sect = "";
		print;
		next;
	}

	if (/^\s*SubSection\s+(\S+)/i) {
		# start of Section
		$subsect = $1;
		$subsect =~ s/\W//g;
		$subsect =~ y/A-Z/a-z/;
		$subsects{$subsect} = 1;
		if ($sect eq "screen" && $subsect eq "display") {
			$got_Mode = 0;
		}
		print;
		next;
	}
	if (/^\s*EndSubSection/i) {
		# end of SubSection
		if ($sect eq "screen") {
			if ($subsect eq "display") {
				if ($depth ne "" && !$set_Depth) {
					print "          ##Xdummy:##\n";
					print "          Depth\t$depth\n";
				}
				if ($geom ne "" && ! $got_Mode) {
					print "          ##Xdummy:##\n";
					print "          Modes\t$geom\n";
				}
			}
		}
		$subsect = "";
		print;
		next;
	}

	$l = $_;
	$l =~ s/#.*$//;
	if ($sect eq "serverflags") {
		if ($l =~ /^\s*Option.*DontVTSwitch/i) {
			$_ =~ s/false/true/ig;
			$got_DontVTSwitch = 1;
		}
		if ($l =~ /^\s*Option.*AllowMouseOpenFail/i) {
			$_ =~ s/false/true/ig;
			$got_AllowMouseOpenFail = 1;
		}
		if ($l =~ /^\s*Option.*PciForceNone/i) {
			$_ =~ s/false/true/ig;
			$got_PciForceNone= 1;
		}
	}
	if ($sect eq "module") {
		if ($l =~ /^\s*Load.*\b(dri|fbdevhw)\b/i) {
			$_ = "##Xdummy## $_";
		}
	}
	if ($sect eq "monitor") {
		if ($l =~ /^\s*HorizSync/i) {
			$got_HorizSync = 1;
		}
		if ($l =~ /^\s*VertRefresh/i) {
			$got_VertRefresh = 1;
		}
	}
	if ($sect eq "device") {
		if ($l =~ /^(\s*Driver)\b/i) {
			$_ = "$1 \"dummy\"\n";
			$got_Driver = 1;
		}
		if ($l =~ /^\s*VideoRam/i) {
			$got_VideoRam= 1;
		}
	}
	if ($sect eq "inputdevice") {
		if ($l =~ /^\s*Option.*\bDevice\b/i) {
			print "  ##Xdummy:##\n";
			$_ = "  Option \"Device\" \"/dev/dilbert$n\"\n";
		}
	}
	if ($sect eq "screen") {
		if ($l =~ /^\s*DefaultDepth\s+(\d+)/i) {
			if ($depth ne "") {
				print "  ##Xdummy:##\n";
				$_ = "  DefaultDepth\t$depth\n";
			}
			$got_DefaultDepth = 1;
		}
		if ($l =~ /^\s*Monitor\s+(\S+)/i) {
			$got_Monitor = $1;
			$got_Monitor =~ s/"//g;
		}
		if ($subsect eq "display") {
			if ($geom ne "") {
				if ($l =~ /^(\s*Modes)\b/i) {
					print "          ##Xdummy:##\n";
					$_ = "$1 $geom\n";
					$got_Modes = 1;
				}
			}
			if ($l =~ /^\s*Depth\s+(\d+)/i) {
				my $d = $1;
				if (!$set_Depth && $depth ne "") {
					$set_Depth = 1;
					if ($depth != $d) {
						print "          ##Xdummy:##\n";
						$_ =  "          Depth\t$depth\n";
					}
				}
			}
		}
	}
	print;
    }
    # create any crucial sections that are missing:
    if (! exists($sects{serverflags})) {
	print "\n##Xdummy:##\n";
    	print "Section \"ServerFlags\"\n";
    	print "  Option \"DontVTSwitch\" \"true\"\n";
    	print "  Option \"AllowMouseOpenFail\" \"true\"\n";
    	print "  Option \"PciForceNone\" \"true\"\n";
    	print "EndSection\n";
    }
    if (! exists($sects{device})) {
	print "\n##Xdummy:##\n";
    	print "Section \"Device\"\n";
    	print "  Identifier \"Videocard0\"\n";
    	print "  Driver \"dummy\"\n";
	print "  VideoRam $videoram\n";
    	print "EndSection\n";
    }
    if (! exists($sects{monitor})) {
	print "\n##Xdummy:##\n";
    	print "Section \"Monitor\"\n";
    	print "  Identifier \"Monitor0\"\n";
    	print "  HorizSync   $HorizSync\n";
    	print "  VertRefresh $VertRefresh\n";
    	print "EndSection\n";
    }
    if (! exists($sects{screen})) {
	print "\n##Xdummy:##\n";
    	print "Section \"Screen\"\n";
    	print "  Identifier \"Screen0\"\n";
    	print "  Device \"Videocard0\"\n";
	if ($got_Monitor ne "") {
    		print "  Monitor \"$got_Monitor\"\n";
	} else {
    		print "  Monitor \"Monitor0\"\n";
	}
	if ($depth ne "") {
    		print "  DefaultDepth $depth\n";
	} else {
    		print "  DefaultDepth 24\n";
	}
    	print "  SubSection \"Display\"\n";
    	print "    Viewport 0 0\n";
    	print "    Depth 24\n";
	if ($geom ne "") {
    		print "    Modes $geom\n";
	} else {
    		print "    Modes \"1280x1024\" \"1024x768\" \"800x600\"\n";
	}
    	print "  EndSubSection\n";
    	print "EndSection\n";
    }
';
}

if [ ! $noconf ]; then
	# tweaked config will be put in $config2:
	config2=""
	if [ "X$config" != "X" ]; then
		if [ ! -f $config ]; then
			config="/etc/X11/$config"
		fi
	else
		# use the default one:
		if [ "X$stype" = "Xxorg" ]; then
			config=/etc/X11/xorg.conf
		else
			if [ -f "/etc/X11/XF86Config-4" ]; then
				config="/etc/X11/XF86Config-4"
			else
				config="/etc/X11/XF86Config"
			fi
		fi
		if [ ! -f $config ]; then
			for c in /etc/X11/xorg.conf /etc/X11/XF86Config-4 /etc/X11/XF86Config
			do
				if [ -f $c ]; then
					config=$c
					break
				fi
			done
		fi
	fi

	if [ ! -f $config ]; then
		config="$XDUMMY_TMPDIR/xorg.conf"
		cat > $config <<END

Section "ServerLayout"
    Identifier     "Layout0"
    Screen      0  "Screen0"
    InputDevice    "Keyboard0" "CoreKeyboard"
    InputDevice    "Mouse0" "CorePointer"
EndSection

Section "Files"
EndSection

Section "Module"
    Load           "dbe"
    Load           "extmod"
    Load           "freetype"
    Load           "glx"
EndSection

Section "InputDevice"
    Identifier     "Mouse0"
    Driver         "mouse"
    Option         "Protocol" "auto"
    Option         "Device" "/dev/psaux"
    Option         "Emulate3Buttons" "no"
    Option         "ZAxisMapping" "4 5"
EndSection

Section "InputDevice"
    Identifier     "Keyboard0"
    Driver         "kbd"
EndSection

Section "Monitor"
    Identifier     "Monitor0"
    VendorName     "Unknown"
    ModelName      "Unknown"
    HorizSync       30.0 - 130.0
    VertRefresh     50.0 - 250.0
    Option         "DPMS"
EndSection

Section "Device"
    Identifier     "Device0"
    Driver         "foovideo"
    VendorName     "foovideo Corporation"
EndSection

Section "Screen"
    Identifier     "Screen0"
    Device         "Device0"
    Monitor        "Monitor0"
    DefaultDepth    24
    SubSection     "Display"
        Depth       24
        Modes           "1280x1024"
    EndSubSection
EndSection

END
	fi

	if [ -f $config ]; then
		tweak_config $config
	fi

	# now we need to get our tweaked config file onto the command line:
	if [ ! $got_config ]; then
		# append to cmdline (FUBAR will be substituted below.)
		if [ "X$stype" = "Xxorg" ]; then
			args="$args -config FUBAR"
		else
			args="$args -xf86config FUBAR"
		fi
	fi
	if [ "X$config2" != "X" ]; then
		# or modify $args:
		c2=$config2
		if [ "X$root" = "X" ]; then
			# ordinary user cannot use absolute path.
			c2=`basename $config2`
		fi
		args=`echo "$args" | sed \
			-e "s,-config  *[^ ][^ ]*,-config $c2,g" \
			-e "s,-xf86config  *[^ ][^ ]*,-xf86config $c2,g"`
	fi
fi

if [ $prconf ]; then
	warn ""
	warn "The Xorg/XFree86 server config file is:"
	warn ""
	if [ "X$config2" = "X" ]; then
		warn "NO CONFIG GENERATED."
		exit 1
	else
		cat "$config2"
	fi
	exit 0
fi

if [ $debug ]; then
	XDUMMY_DEBUG=1
	export XDUMMY_DEBUG
fi
if [ $root ]; then
	XDUMMY_ROOT=1
	export XDUMMY_ROOT
fi

# Finally, run it:
#
if [ "X$debug" != "X" -o "X$runit" = "X" ]; then
	if [ ! $runit ]; then
		echo ""
		echo "/usr/bin/env:"
		env | egrep -v '^(LS_COLORS|TERMCAP)' | sort
		echo ""
		echo "XDUMMY*:"
		env | grep '^XDUMMY' | sort
		echo ""
	fi
	warn ""
	warn "The command to run is:"
	warn ""
	so=$SO
	pwd=`pwd`
	if echo "$so" | grep '^\./' > /dev/null; then
		so=`echo "$so" | sed -e "s,^\.,$pwd,"`
	fi
	if echo "$so" | grep '/' > /dev/null; then
		:
	else
		so="$pwd/$so"
	fi
	warn "env LD_PRELOAD=$so $xserver $disp $args $vt"
	warn ""
	if [ ! $runit ]; then
		exit 0
	fi
fi

if [ $strace ]; then
	strace -f env LD_PRELOAD=$SO $xserver $disp $args $vt
else
	exec env LD_PRELOAD=$SO $xserver $disp $args $vt
fi

exit $?

#########################################################################

code() {
#code_begin
#include <stdio.h>
#define O_ACCMODE          0003
#define O_RDONLY             00
#define O_WRONLY             01
#define O_RDWR               02
#define O_CREAT            0100 /* not fcntl */
#define O_EXCL             0200 /* not fcntl */
#define O_NOCTTY           0400 /* not fcntl */
#define O_TRUNC           01000 /* not fcntl */
#define O_APPEND          02000
#define O_NONBLOCK        04000
#define O_NDELAY        O_NONBLOCK
#define O_SYNC           010000
#define O_FSYNC          O_SYNC
#define O_ASYNC          020000

#include <unistd.h>
#include <stdlib.h>
#include <string.h>

#include <linux/vt.h>
#include <linux/kd.h>

#define __USE_GNU
#include <dlfcn.h>

static char tmpdir[4096];
static char str1[4096];
static char str2[4096];

static char devs[256][1024];
static int debug = -1;
static int root = -1;
static int changed_uid = 0;
static int saw_fonts = 0;
static int saw_lib_modules = 0;

static time_t start = 0; 

void check_debug(void) {
	if (debug < 0) {
		if (getenv("XDUMMY_DEBUG") != NULL) {
			debug = 1;
		} else {
			debug = 0;
		}
		/* prevent other processes using the preload: */
		putenv("LD_PRELOAD=");
	}
}
void check_root(void) {
	if (root < 0) {
		/* script tells us if we are root */
		if (getenv("XDUMMY_ROOT") != NULL) {
			root = 1;
		} else {
			root = 0;
		}
	}
}

void check_uid(void) {
	if (start == 0) {
		start = time(NULL);
		if (debug) fprintf(stderr, "START: %u\n", (unsigned int) start);
		return;
	} else if (changed_uid == 0) {
		if (saw_fonts || time(NULL) > start + 20) {
			if (getenv("XDUMMY_UID")) {
				int uid = atoi(getenv("XDUMMY_UID"));
				if (debug) fprintf(stderr, "SETREUID: %d saw_fonts=%d\n", uid, saw_fonts);
				if (uid >= 0) {
					/* this will simply fail in -nonroot mode: */
					setreuid(uid, -1);
				}
			}
			changed_uid = 1;
		}
	}
}

#define CHECKIT if (debug < 0) check_debug(); \
		if (root  < 0) check_root(); \
		check_uid();

static void set_tmpdir(void) {
	char *s;
	static int didset = 0;
	if (didset) {
		return;
	}
	s = getenv("XDUMMY_TMPDIR");
	if (! s) {
		s = "/tmp";
	}
	tmpdir[0] = '\0';
	strcat(tmpdir, s);
	strcat(tmpdir, "/");
	didset = 1;
}

static char *tmpdir_path(const char *path) {
	char *str;
	set_tmpdir();
	strcpy(str2, path);
	str = str2;
	while (*str) {
		if (*str == '/') {
			*str = '_';
		}
		str++;
	}
	strcpy(str1, tmpdir);
	strcat(str1, str2);
	return str1;
}

int open(const char *pathname, int flags, unsigned short mode) {
	int fd;
	char *store_dev = NULL;
	static int (*real_open)(const char *, int , unsigned short) = NULL;

	CHECKIT
	if (! real_open) {
		real_open = (int (*)(const char *, int , unsigned short))
			dlsym(RTLD_NEXT, "open");
	}

	if (strstr(pathname, "lib/modules/")) {
		/* not currently used. */
		saw_lib_modules = 1;
	}

	if (!root) {
		if (strstr(pathname, "/dev/") == pathname) {
			store_dev = strdup(pathname);
		}
		if (strstr(pathname, "/dev/tty") == pathname && strcmp(pathname, "/dev/tty")) {
			pathname = tmpdir_path(pathname);
			if (debug) fprintf(stderr, "OPEN: %s -> %s (as FIFO)\n", store_dev, pathname);
			/* we make it a FIFO so ioctl on it does not fail */
			unlink(pathname);
			mkfifo(pathname, 0666);
		} else if (0) {
			/* we used to handle more /dev files ... */
			fd = real_open(pathname, O_WRONLY|O_CREAT, 0777);
			close(fd);
		}
	}

	fd = real_open(pathname, flags, mode);

	if (debug) fprintf(stderr, "OPEN: %s %d %d fd=%d\n", pathname, flags, mode, fd);

	if (! root) {
		if (store_dev) {
			if (fd < 256) {
				strcpy(devs[fd], store_dev);
			}
			free(store_dev);
		}
	}

	return(fd);
}

int open64(const char *pathname, int flags, unsigned short mode) {
	int fd;

	CHECKIT
	if (debug) fprintf(stderr, "OPEN64: %s %d %d\n", pathname, flags, mode);

	fd = open(pathname, flags, mode);
	return(fd);
}

int rename(const char *oldpath, const char *newpath) {
	static int (*real_rename)(const char *, const char *) = NULL;

	CHECKIT
	if (! real_rename) {
		real_rename = (int (*)(const char *, const char *))
			dlsym(RTLD_NEXT, "rename");
	}

	if (debug) fprintf(stderr, "RENAME: %s %s\n", oldpath, newpath);

	if (root) {
		return(real_rename(oldpath, newpath));
	}

	if (strstr(oldpath, "/var/log") == oldpath) {
		if (debug) fprintf(stderr, "RENAME: returning 0\n");
		return 0;
	}
	return(real_rename(oldpath, newpath));
}

FILE *fopen(const char *pathname, const char *mode) {
	static FILE* (*real_fopen)(const char *, const char *) = NULL;
	char *str;

	if (! saw_fonts) {
		if (strstr(pathname, "/fonts/")) {
			if (strstr(pathname, "fonts.dir")) {
				saw_fonts = 1;
			} else if (strstr(pathname, "fonts.alias")) {
				saw_fonts = 1;
			}
		}
	}

	CHECKIT
	if (! real_fopen) {
		real_fopen = (FILE* (*)(const char *, const char *))
			dlsym(RTLD_NEXT, "fopen");
	}

	if (debug) fprintf(stderr, "FOPEN: %s %s\n", pathname, mode);

	if (strstr(pathname, "xdummy_modified_xconfig.conf")) {
		/* make our config appear to be in /etc/X11, etc. */
		char *q = strrchr(pathname, '/');
		if (q != NULL && getenv("XDUMMY_TMPDIR") != NULL) {
			strcpy(str1, getenv("XDUMMY_TMPDIR"));
			strcat(str1, q);
			if (debug) fprintf(stderr, "FOPEN: %s -> %s\n", pathname, str1);
			pathname = str1;
		}
	}

	if (root) {
		return(real_fopen(pathname, mode));
	}

	str = (char *) pathname;
	if (strstr(pathname, "/var/log") == pathname) {
		str = tmpdir_path(pathname);
		if (debug) fprintf(stderr, "FOPEN: %s -> %s\n", pathname, str);
	}
	return(real_fopen(str, mode));
}


#define RETURN0 if (debug) \
	{fprintf(stderr, "IOCTL: covered %d 0x%x\n", fd, req);} return 0;
#define RETURN1 if (debug) \
	{fprintf(stderr, "IOCTL: covered %d 0x%x\n", fd, req);} return -1;

int ioctl(int fd, int req, void *ptr) {
	static int closed_xf86Info_consoleFd = 0;
	static int (*real_ioctl)(int, int , void *) = NULL;

	CHECKIT
	if (! real_ioctl) {
		real_ioctl = (int (*)(int, int , void *))
			dlsym(RTLD_NEXT, "open");
	}
	if (debug) fprintf(stderr, "IOCTL: %d 0x%x %p\n", fd, req, ptr);

	/* based on xorg-x11-6.8.1-dualhead.patch */
	if (req == VT_GETMODE) {
		/* close(xf86Info.consoleFd) */
		if (0 && ! closed_xf86Info_consoleFd) {
			/* I think better not to close it... */
			close(fd);
			closed_xf86Info_consoleFd = 1;
		}
		RETURN0
	} else if (req == VT_SETMODE) {
		RETURN0
	} else if (req == VT_GETSTATE) {
		RETURN0
	} else if (req == KDSETMODE) {
		RETURN0
	} else if (req == KDSETLED) {
		RETURN0
	} else if (req == KDGKBMODE) {
		RETURN0
	} else if (req == KDSKBMODE) {
		RETURN0
	} else if (req == VT_ACTIVATE) {
		RETURN0
	} else if (req == VT_WAITACTIVE) {
		RETURN0
	} else if (req == VT_RELDISP) {
		if (ptr == (void *) 1) {
			RETURN1
		} else if (ptr == (void *) VT_ACKACQ) {
			RETURN0
		}
	}

	return(real_ioctl(fd, req, ptr));
}

typedef void (*sighandler_t)(int);
#define SIGUSR1       10
#define SIG_DFL       ((sighandler_t)0)

sighandler_t signal(int signum, sighandler_t handler) {
	static sighandler_t (*real_signal)(int, sighandler_t) = NULL;

	CHECKIT
	if (! real_signal) {
		real_signal = (sighandler_t (*)(int, sighandler_t))
			dlsym(RTLD_NEXT, "signal");
	}

	if (debug) fprintf(stderr, "SIGNAL: %d %p\n", signum, handler);

	if (signum == SIGUSR1) {
		if (debug) fprintf(stderr, "SIGNAL: skip SIGUSR1\n");
		return SIG_DFL;
	}
	
	return(real_signal(signum, handler));
}

int close(int fd) {
	static int (*real_close)(int) = NULL;

	CHECKIT
	if (! real_close) {
		real_close = (int (*)(int)) dlsym(RTLD_NEXT, "close");
	}

	if (debug) fprintf(stderr, "CLOSE: %d\n", fd);
	if (!root) {
		if (fd < 256) {
			devs[fd][0] = '\0';
		}
	}
	return(real_close(fd));
}

struct stat {
	int foo;
};

int stat(const char *path, struct stat *buf) {
	static int (*real_stat)(const char *, struct stat *) = NULL;

	CHECKIT
	if (! real_stat) {
		real_stat = (int (*)(const char *, struct stat *))
			dlsym(RTLD_NEXT, "stat");
	}

	if (debug) fprintf(stderr, "STAT: %s\n", path);

	return(real_stat(path, buf));
}

int stat64(const char *path, struct stat *buf) {
	static int (*real_stat64)(const char *, struct stat *) = NULL;

	CHECKIT
	if (! real_stat64) {
		real_stat64 = (int (*)(const char *, struct stat *))
			dlsym(RTLD_NEXT, "stat64");
	}

	if (debug) fprintf(stderr, "STAT64: %s\n", path);

	return(real_stat64(path, buf));
}

int chown(const char *path, uid_t owner, gid_t group) {
	static int (*real_chown)(const char *, uid_t, gid_t) = NULL;

	CHECKIT
	if (! real_chown) {
		real_chown = (int (*)(const char *, uid_t, gid_t))
			dlsym(RTLD_NEXT, "chown");
	}

	if (root) {
		return(real_chown(path, owner, group));
	}

	if (debug) fprintf(stderr, "CHOWN: %s %d %d\n", path, owner, group);

	if (strstr(path, "/dev") == path) {
		if (debug) fprintf(stderr, "CHOWN: return 0\n");
		return 0;
	}

	return(real_chown(path, owner, group));
}


int ioperm(unsigned long from, unsigned long num, int turn_on) {
	static int (*real_ioperm)(unsigned long, unsigned long, int) = NULL;

	CHECKIT
	if (! real_ioperm) {
		real_ioperm = (int (*)(unsigned long, unsigned long, int))
			dlsym(RTLD_NEXT, "ioperm");
	}
	if (debug) fprintf(stderr, "IOPERM: %d %d %d\n", (int) from, (int) num, turn_on);
	if (root) {
		return(real_ioperm(from, num, turn_on));
	}
	return 0;
}

int iopl(int level) {
	static int (*real_iopl)(int) = NULL;

	CHECKIT
	if (! real_iopl) {
		real_iopl = (int (*)(int)) dlsym(RTLD_NEXT, "iopl");
	}
	if (debug) fprintf(stderr, "IOPL: %d\n", level);
	if (root) {
		return(real_iopl(level));
	}
	return 0;
}

#if 0

/*
 * we got things to work w/o pretending to be root.
 * so we no longer interpose getuid(), etc.
 */

uid_t getuid(void) {
	static uid_t (*real_getuid)(void) = NULL;
	CHECKIT
	if (! real_getuid) {
		real_getuid = (uid_t (*)(void)) dlsym(RTLD_NEXT, "getuid");
	}
	if (root) {
		return(real_getuid());
	}
	if (debug) fprintf(stderr, "GETUID: 0\n");
	return 0;
}
uid_t geteuid(void) {
	static uid_t (*real_geteuid)(void) = NULL;
	CHECKIT
	if (! real_geteuid) {
		real_geteuid = (uid_t (*)(void)) dlsym(RTLD_NEXT, "geteuid");
	}
	if (root) {
		return(real_geteuid());
	}
	if (debug) fprintf(stderr, "GETEUID: 0\n");
	return 0;
}
uid_t geteuid_kludge1(void) {
	static uid_t (*real_geteuid)(void) = NULL;
	CHECKIT
	if (! real_geteuid) {
		real_geteuid = (uid_t (*)(void)) dlsym(RTLD_NEXT, "geteuid");
	}
	if (debug) fprintf(stderr, "GETEUID: 0 saw_libmodules=%d\n", saw_lib_modules);
	if (root && !saw_lib_modules) {
		return(real_geteuid());
	} else {
		saw_lib_modules = 0;
		return 0;
	}
}

uid_t getuid32(void) {
	static uid_t (*real_getuid32)(void) = NULL;
	CHECKIT
	if (! real_getuid32) {
		real_getuid32 = (uid_t (*)(void)) dlsym(RTLD_NEXT, "getuid32");
	}
	if (root) {
		return(real_getuid32());
	}
	if (debug) fprintf(stderr, "GETUID32: 0\n");
	return 0;
}
uid_t geteuid32(void) {
	static uid_t (*real_geteuid32)(void) = NULL;
	CHECKIT
	if (! real_geteuid32) {
		real_geteuid32 = (uid_t (*)(void)) dlsym(RTLD_NEXT, "geteuid32");
	}
	if (root) {
		return(real_geteuid32());
	}
	if (debug) fprintf(stderr, "GETEUID32: 0\n");
	return 0;
}

gid_t getgid(void) {
	static gid_t (*real_getgid)(void) = NULL;
	CHECKIT
	if (! real_getgid) {
		real_getgid = (gid_t (*)(void)) dlsym(RTLD_NEXT, "getgid");
	}
	if (root) {
		return(real_getgid());
	}
	if (debug) fprintf(stderr, "GETGID: 0\n");
	return 0;
}
gid_t getegid(void) {
	static gid_t (*real_getegid)(void) = NULL;
	CHECKIT
	if (! real_getegid) {
		real_getegid = (gid_t (*)(void)) dlsym(RTLD_NEXT, "getegid");
	}
	if (root) {
		return(real_getegid());
	}
	if (debug) fprintf(stderr, "GETEGID: 0\n");
	return 0;
}
gid_t getgid32(void) {
	static gid_t (*real_getgid32)(void) = NULL;
	CHECKIT
	if (! real_getgid32) {
		real_getgid32 = (gid_t (*)(void)) dlsym(RTLD_NEXT, "getgid32");
	}
	if (root) {
		return(real_getgid32());
	}
	if (debug) fprintf(stderr, "GETGID32: 0\n");
	return 0;
}
gid_t getegid32(void) {
	static gid_t (*real_getegid32)(void) = NULL;
	CHECKIT
	if (! real_getegid32) {
		real_getegid32 = (gid_t (*)(void)) dlsym(RTLD_NEXT, "getegid32");
	}
	if (root) {
		return(real_getegid32());
	}
	if (debug) fprintf(stderr, "GETEGID32: 0\n");
	return 0;
}
#endif

#if 0
/* maybe we need to interpose on strcmp someday... here is the template */
int strcmp(const char *s1, const char *s2) {
	static int (*real_strcmp)(const char *, const char *) = NULL;
	CHECKIT
	if (! real_strcmp) {
		real_strcmp = (int (*)(const char *, const char *)) dlsym(RTLD_NEXT, "strcmp");
	}
	if (debug) fprintf(stderr, "STRCMP: '%s' '%s'\n", s1, s2);
	return(real_strcmp(s1, s2));
}
#endif

#code_end
}