x11vnc: rename -create_x to -create_xsrv. Hopefully done fixing Xdummy.

1 files changed, 212 insertions, 122 deletions

diff --git a/x11vnc/misc/Xdummy b/x11vnc/misc/Xdummy
index 3abc199..452eb4d 100755
--- a/x11vnc/misc/Xdummy
+++ b/x11vnc/misc/Xdummy
@@ -5,17 +5,19 @@
 #
 # Run "Xdummy -help" for more info.
 #
-xserver=""
-geom=""
-geom=""
 install=""
 uninstall=""
+runit=1
+prconf=""
+notweak=""
 root=""
+nosudo=""
+xserver=""
+geom=""
+depth=""
 debug=""
 strace=""
-runit=1
-prconf=""
-noconf=""
+cmdline_config=""
 
 PATH=$PATH:/bin:/usr/bin
 export PATH
@@ -24,55 +26,62 @@ program=`basename "$0"`
 
 help () {
 	${PAGER:-more} << END
+$program:
 
-$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".  
+    A hack to run a stock Xorg(1) or XFree86(1) X server with the "dummy"
+    (RAM-only framebuffer) video driver such that it AVOIDS the Linux VT
+    switching, opening device files in /dev, keyboard and mouse conflicts,
+    and other problems associated with the normal use of "dummy".
 
-In other words, try to make Xorg/XFree86 with the Device "dummy" driver
-act more like Xvfb(1).
+    In other words, it tries to make Xorg/XFree86 with the "dummy"
+    device 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.)  One nice thing is the dummy server supports RANDR
+    dynamic resizing while Xvfb does not.
 
-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.
+    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.)
+    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 (e.g. avoid the VT stuff.)
+    LD_PRELOAD tricks are usually "clever hacks" and so might not work
+    in all situations or break when something changes.
 
-Also, gcc/cc is required to compile the LD_PRELOAD shared object.
-See -install and -uninstall described below.
+    This program does not need to be run as root as of 12/2009.  However,
+    if there are problems for certain situations (usually older servers)
+    it may perform better if run as root (use the -root option.)
 
+    Also, gcc/cc and other build tools are required for this script to
+    be able to compile the LD_PRELOAD shared object.  Be sure they are
+    installed on the system.  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.
+    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 that
+    need to install.
 
 Usage:
 
-	$program <${program}-args> [--] <Xserver-args>
+	$program <${program}-args> <Xserver-args>
 
+	(actually, the arguments can be supplied in any order.)
 
 Examples:
 
+	$program -install
+
 	$program :1
 
-	$program -debug -tmpdir ~/mytmp :1
+	$program -debug :1
 
-	$program -install
+	$program -tmpdir ~/mytmp :1 -nolisten tcp
 
 startx example:
 
@@ -95,6 +104,8 @@ xdm example:
 	     :1 local /usr/local/dummy/Xdummy :1 -debug
 	     :2 local /usr/local/dummy/Xdummy :2 -debug
 
+        (-debug is optional)
+
 gdm/kdm example:
 
 	TBD.
@@ -102,11 +113,12 @@ gdm/kdm example:
 Root permission and x11vnc:
 
 	Update: as of 12/2009 this program no longer must be run as root.
+	So try it as non-root before running it as root and/or the
+	following schemes.
 
-	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:
+	In some circumstances X server 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:
 
@@ -145,25 +157,38 @@ Options:
     ${program}-args:
 
 	-install	Compile the LD_PRELOAD shared object and install it
-			next to the $program script file as: $0.so
+			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).
+			object is compiled as a file in /tmp (or -tmpdir)
+
+			If you set the environment variable
+			INTERPOSE_GETUID=1 when building, then when
+			$program is run as an ordinary user, the shared
+			object will interpose getuid() calls and pretend
+			to be root.  Otherwise it doesn't pretend to
+			be root.
+
+			You can also set the CFLAGS environment variable
+			to anything else you want on the compile cmdline.
+
+	-uninstall	Remove the file:
+
+			  $0.so
 
-	-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.
+	The X server is not started under -install, -uninstall, or -prconf.
 
 
-	: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.
+	:N		The DISPLAY (e.g. :15) is often the first
+			argument.  It is passed to the real X server and
+			also used by the Xdummy script as an identifier.
 
 	-geom geom1[,geom2...]  Take the geometry (e.g. 1024x768) or
 			list of geometries and insert them into the
@@ -171,6 +196,13 @@ Options:
 			config file.  Use this to have a smaller geometry
 			than the one in the system config file.
 
+	-depth n	Use pixel color depth n (e.g. 8, 16, or 24). This
+			makes sure the X config file has a Screen.Display
+			subsection of this depth.  Note this option is
+			ALSO passed to the X server.
+
+	-DEPTH n	Same as -depth, except not passed to X server.
+
 	-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
@@ -179,56 +211,70 @@ Options:
 	-nonroot	Run in non-root mode (working 12/2009, now default)
 
 	-root		Run as root (may still be needed in some
-			environments.)
+			environments.)  Same as XDUMMY_RUN_AS_ROOT=1.
 
 	-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:
+			those are not in \$PATH, it tries these locations:
+				/usr/bin/Xorg
 				/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.
+			if needed.  Also note any XDUMMY* environment
+			variables that need to be set.
 
-	-prconf		Print, to stdout, the tweaked Xorg or XFree86
+	-prconf		Print, to stdout, the tweaked Xorg/XFree86
 			config file (-config and -xf86config server
-			options, respectively).  The Xserver is not
+			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.
+	-notweak	Do not tweak (modify) the Xorg/XFree86 config file
+			(system or server command line) at all.  The -geom
+			and similar config file modifications are ignored.
+
+			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 the
+			-prconf output.
 
 	-debug		Extra debugging output.
 
-	-strace		strace(1) the Xserver process (for troubleshooting).
+	-strace		strace(1) the Xserver process (for troubleshooting.)
+	-ltrace		ltrace(1) instead of strace (can be slow.)
 
 	-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:
+	Most of the Xorg and XFree86 options will work and are simply
+	passed along if you supply them.  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).
+			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).
+	If -config/-xf86config is not given, the system one
+	(e.g. /etc/X11/xorg.conf) is used.  If the system one cannot be
+	found, a built-in one is used.	Any settings in the config file
+	that are not consistent with "dummy" mode will be overwritten
+	(unless -notweak is specified.)
+
+	If "file" is only a basename (e.g. "xorg.dummy.conf") with no /'s,
+	then no tweaking of it is done: the X server will look for that
+	basename via its normal search algorithm.  If the found file does
+	not refer to the "dummy" driver, etc, then the X server will fail.
 
 Notes:
 
@@ -236,17 +282,20 @@ Notes:
     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 Xserver-arg (e.g. :1) is not given, or ":" is given
+    that indicates $program should try to find a free one (based on
+    tcp ports.)
 
     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). 
+    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
+    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 :-)
 
+    Set XDUMMY_SET_XV=1 to turn on debugging output for this script.
+
 END
 }
 
@@ -311,8 +360,6 @@ if [ "X$XDUMMY_SU_EXEC" = "X" -a "X$root" = "X1" -a "X`id -u`" != "X0"  ]; then
 			dosu=""
 		elif [ "X$arg" = "X-prconf" ]; then
 			dosu=""
-		elif [ "X$arg" = "X--" ]; then
-			break
 		fi
 	done
 	if [ $dosu ]; then
@@ -337,6 +384,7 @@ if [ "X$XDUMMY_SU_EXEC" = "X" -a "X$root" = "X1" -a "X`id -u`" != "X0"  ]; then
 				exec su -c "$0 $*"
 			fi
 		fi
+		# DONE:
 		exit
 	fi
 fi
@@ -345,17 +393,21 @@ fi
 #
 disp=""
 args=""
+cmdline_config=""
 
 # Process Xdummy args:
 #
 while [ "X$1" != "X" ]
 do
+    if [ "X$1" = "X-config" -o "X$1" = "X-xf86config" ]; then
+    	cmdline_config="$2"
+    fi
     case $1 in 
 	":"*)	disp=$1
                 ;;
-	"-install") install=1
+	"-install") install=1; runit=""
                 ;;
-	"-uninstall") uninstall=1
+	"-uninstall") uninstall=1; runit=""
                 ;;
 	"-n")  runit=""
                 ;;
@@ -363,9 +415,11 @@ do
                 ;;
 	"-norun") runit=""
                 ;;
-	"-prconf") prconf=1
+	"-prconf") prconf=1; runit=""
                 ;;
-	"-noconf") noconf=1
+	"-notweak") notweak=1
+                ;;
+	"-noconf")  notweak=1
                 ;;
 	"-nonroot") root=""
                 ;;
@@ -378,21 +432,26 @@ do
 	"-uid") XDUMMY_UID="$2"; shift
 		export XDUMMY_UID
                 ;;
-	"-geom"*) geom="$2"; shift
+	"-geom") geom="$2"; shift
+                ;;
+	"-depth") depth="$2"; args="$args -depth $2";
+		  shift
                 ;;
-	"-depth") depth="$2"; shift
+	"-DEPTH") depth="$2"; shift
                 ;;
 	"-tmpdir") XDUMMY_TMPDIR="$2"; shift
                 ;;
-	"-debug") debug=1
+	"-debug")   debug=1
                 ;;
 	"-nodebug") debug=""
                 ;;
 	"-strace") strace=1
                 ;;
-	"-h"*)	help; exit 0
+	"-ltrace") strace=2
+                ;;
+	"-h")	 help; exit 0
                 ;;
-	"--")	shift; break
+	"-help") help; exit 0
                 ;;
 	*)	args="$args $1"
                 ;;
@@ -433,32 +492,45 @@ 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.$$.c
+	tmp=$tdir/Xdummy.$RANDOM$$.c
 	rm -f $tmp
 	if [ -e $tmp -o -h $tmp ]; then
 		warn "$tmp still exists."
 		exit 1
 	fi
+	touch $tmp || exit 1
 	tail -n +$n1 $0 | head -n $dn > $tmp
 
 	# compile it to Xdummy.so:
+	if [ -f $SO ]; then
+		mv $SO $SO.$$
+		rm -f $SO.$$
+	fi
 	rm -f $SO
 	touch $SO
 	if [ ! -f $SO ]; then
 		SO=$tdir/Xdummy.$user.so
 		warn "warning switching LD_PRELOAD shared object to: $SO"
 	fi
+
+	if [ -f $SO ]; then
+		mv $SO $SO.$$
+		rm -f $SO.$$
+	fi
 	rm -f $SO
 
 	# we assume gcc:
-	cc -shared -fPIC -o $SO $tmp
+	if [ "X$INTERPOSE_GETUID" = "X1" ]; then
+		CFLAGS="$CFLAGS -DINTERPOSE_GETUID"
+	fi
+	echo "$program:" cc -shared -fPIC $CFLAGS -o $SO $tmp
+                         cc -shared -fPIC $CFLAGS -o $SO $tmp
 	rc=$?
 	rm -f $tmp
 	if [ $rc != 0 ]; then
@@ -485,6 +557,10 @@ if [ "X$install" != "X" -o "X$uninstall" != "X" ]; then
 	if [ -e $SO -o -h $SO ]; then
 		warn "$program: removing $SO"
 	fi
+	if [ -f $SO ]; then
+		mv $SO $SO.$$
+		rm -f $SO.$$
+	fi
 	rm -f $SO
 	if [ -e $SO -o -h $SO ]; then
 		warn "warning: $SO still exists."
@@ -736,37 +812,12 @@ fi
 # Decide flavor of Xserver:
 #
 stype=`basename "$xserver"`
-if echo "$stype" | grep -i xorg > /dev/null; then
-	stype=xorg
-else
+if echo "$stype" | grep -i xfree86 > /dev/null; then
 	stype=xfree86
+else
+	stype=xorg
 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"
@@ -795,6 +846,10 @@ tweak_config() {
 	$geom = $tmp;
     }
     while (<>) {
+	if ($ENV{XDUMMY_NOTWEAK}) {
+		print $_;
+		next;
+	}
 	$n++;
 	if (/^\s*#/) {
 		# pass comments straight thru
@@ -967,6 +1022,9 @@ tweak_config() {
 	}
 	print;
     }
+    if ($ENV{XDUMMY_NOTWEAK}) {
+	exit;
+    }
     # create any crucial sections that are missing:
     if (! exists($sects{serverflags})) {
 	print "\n##Xdummy:##\n";
@@ -1021,14 +1079,31 @@ tweak_config() {
 ';
 }
 
-if [ ! $noconf ]; then
+# Work out config file and tweak it.
+#
+if [ "X$cmdline_config" = "X" ]; then
+	:
+elif echo "$cmdline_config" | grep '/' > /dev/null; then
+	:
+else
+	# ignore basename only case (let server handle it)
+	cmdline_config=""
+	notweak=1
+fi
+
+config=$cmdline_config
+
+if [ "X$notweak" = "X1" -a "X$root" = "X" -a  -f "$cmdline_config" ]; then
+	# if not root we need to copy (but not tweak) the specified config.
+	XDUMMY_NOTWEAK=1
+	export XDUMMY_NOTWEAK
+	notweak=""
+fi
+
+if [ ! $notweak ]; then
 	# tweaked config will be put in $config2:
 	config2=""
-	if [ "X$config" != "X" ]; then
-		if [ ! -f $config ]; then
-			config="/etc/X11/$config"
-		fi
-	else
+	if [ "X$config" = "X" ]; then
 		# use the default one:
 		if [ "X$stype" = "Xxorg" ]; then
 			config=/etc/X11/xorg.conf
@@ -1052,6 +1127,7 @@ if [ ! $noconf ]; then
 
 	if [ ! -f $config ]; then
 		config="$XDUMMY_TMPDIR/xorg.conf"
+		warn "$program: using minimal built-in xorg.conf settings."
 		cat > $config <<END
 
 Section "ServerLayout"
@@ -1119,7 +1195,7 @@ END
 	fi
 
 	# now we need to get our tweaked config file onto the command line:
-	if [ ! $got_config ]; then
+	if [ "X$cmdline_config" = "X" ]; then
 		# append to cmdline (FUBAR will be substituted below.)
 		if [ "X$stype" = "Xxorg" ]; then
 			args="$args -config FUBAR"
@@ -1142,7 +1218,7 @@ fi
 
 if [ $prconf ]; then
 	warn ""
-	warn "The Xorg/XFree86 server config file is:"
+	warn "Printing out the Xorg/XFree86 server config file:"
 	warn ""
 	if [ "X$config2" = "X" ]; then
 		warn "NO CONFIG GENERATED."
@@ -1195,7 +1271,11 @@ if [ "X$debug" != "X" -o "X$runit" = "X" ]; then
 fi
 
 if [ $strace ]; then
-	strace -f env LD_PRELOAD=$SO $xserver $disp $args $vt
+	if [ "X$strace" = "X2" ]; then
+		ltrace -f env LD_PRELOAD=$SO $xserver $disp $args $vt
+	else
+		strace -f env LD_PRELOAD=$SO $xserver $disp $args $vt
+	fi
 else
 	exec env LD_PRELOAD=$SO $xserver $disp $args $vt
 fi
@@ -1597,6 +1677,10 @@ int chown(const char *path, uid_t owner, gid_t group) {
 	return(real_chown(path, owner, group));
 }
 
+extern int *__errno_location (void);
+#ifndef ENODEV
+#define ENODEV 19
+#endif
 
 int ioperm(unsigned long from, unsigned long num, int turn_on) {
 	static int (*real_ioperm)(unsigned long, unsigned long, int) = NULL;
@@ -1610,6 +1694,12 @@ int ioperm(unsigned long from, unsigned long num, int turn_on) {
 	if (root) {
 		return(real_ioperm(from, num, turn_on));
 	}
+	if (from == 0 && num == 1024 && turn_on == 1) {
+		/* we want xf86EnableIO to fail */
+		if (debug) fprintf(stderr, "IOPERM: setting ENODEV.\n");
+		*__errno_location() = ENODEV;
+		return -1;
+	}
 	return 0;
 }
 
@@ -1627,7 +1717,7 @@ int iopl(int level) {
 	return 0;
 }
 
-#if 0
+#ifdef INTERPOSE_GETUID 
 
 /*
  * we got things to work w/o pretending to be root.