1 files changed, 376 insertions, 0 deletions
diff --git a/tdm/backend/server.c b/tdm/backend/server.c
new file mode 100644
index 000000000..e78d8a66c
--- /dev/null
+++ b/tdm/backend/server.c
@@ -0,0 +1,376 @@
+/*
+
+Copyright 1988, 1998  The Open Group
+Copyright 2001,2003,2005 Oswald Buddenhagen <[email protected]>
+
+Permission to use, copy, modify, distribute, and sell this software and its
+documentation for any purpose is hereby granted without fee, provided that
+the above copyright notice appear in all copies and that both that
+copyright notice and this permission notice appear in supporting
+documentation.
+
+The above copyright notice and this permission notice shall be included
+in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
+OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+OTHER DEALINGS IN THE SOFTWARE.
+
+Except as contained in this notice, the name of a copyright holder shall
+not be used in advertising or otherwise to promote the sale, use or
+other dealings in this Software without prior written authorization
+from the copyright holder.
+
+*/
+
+/*
+ * xdm - display manager daemon
+ * Author: Keith Packard, MIT X Consortium
+ *
+ * server.c - manage the X server
+ */
+
+#include "dm.h"
+#include "dm_error.h"
+#include "dm_socket.h"
+
+#include <X11/Xlib.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <signal.h>
+
+
+struct display *startingServer;
+time_t serverTimeout = TO_INF;
+
+char **
+PrepServerArgv( struct display *d, const char *args )
+{
+	char **argv;
+#ifdef HAVE_VTS
+	char vtstr[8];
+#endif
+
+	if (!(argv = parseArgs( 0, d->serverCmd )) ||
+	    !(argv = parseArgs( argv, args )) ||
+	    !(argv = addStrArr( argv, d->name, -1 )))
+		exit( 47 );
+#ifdef HAVE_VTS
+	if (d->serverVT &&
+	    !(argv = addStrArr( argv, vtstr,
+	                        sprintf( vtstr, "vt%d", d->serverVT ) )))
+		exit( 47 );
+#endif
+	return argv;
+}
+
+static void
+StartServerOnce( void )
+{
+	struct display *d = startingServer;
+	char **argv;
+	int pid;
+
+	Debug( "StartServerOnce for %s, try %d\n", d->name, ++d->startTries );
+	d->serverStatus = starting;
+	switch (pid = Fork()) {
+	case 0:
+		argv = PrepServerArgv( d, d->serverArgsLocal );
+		if (d->authFile) {
+			if (!(argv = addStrArr( argv, "-auth", 5 )) ||
+			    !(argv = addStrArr( argv, d->authFile, -1 )))
+				exit( 47 );
+		}
+		Debug( "exec %\"[s\n", argv );
+		/*
+		 * give the server SIGUSR1 ignored,
+		 * it will notice that and send SIGUSR1
+		 * when ready
+		 */
+		(void)Signal( SIGUSR1, SIG_IGN );
+		(void)execv( argv[0], argv );
+		LogError( "X server %\"s cannot be executed\n", argv[0] );
+		
+		/* Let's try again with some standard paths */
+		argv[0] = (char *)realloc(argv[0], strlen("/usr/X11R6/bin/X") + 1);
+		if (argv[0] != NULL) {
+			argv[0] = "/usr/X11R6/bin/X";
+			Debug( "exec %\"[s\n", argv );
+			(void)execv( argv[0], argv );
+			LogError( "X server %\"s cannot be executed\n", argv[0] );
+		
+			argv[0] = "/usr/bin/X"; /* Shorter than the previous file name */
+			Debug( "exec %\"[s\n", argv );
+			(void)execv( argv[0], argv );
+			LogError( "X server %\"s cannot be executed\n", argv[0] );
+		}
+		
+		exit( 47 );
+	case -1:
+		LogError( "X server fork failed\n" );
+		StartServerFailed();
+		break;
+	default:
+		Debug( "X server forked, pid %d\n", pid );
+		d->serverPid = pid;
+		serverTimeout = d->serverTimeout + now;
+		break;
+	}
+}
+
+void
+StartServer( struct display *d )
+{
+	startingServer = d;
+	d->startTries = 0;
+	StartServerOnce();
+}
+
+void
+AbortStartServer( struct display *d )
+{
+	if (startingServer == d)
+	{
+		if (d->serverStatus != ignore)
+		{
+			d->serverStatus = ignore;
+			serverTimeout = TO_INF;
+			Debug( "aborting X server start\n" );
+		}
+		startingServer = 0;
+	}
+}
+
+void
+StartServerSuccess()
+{
+	struct display *d = startingServer;
+	d->serverStatus = ignore;
+	serverTimeout = TO_INF;
+	Debug( "X server ready, starting session\n" );
+	StartDisplayP2( d );
+}
+
+void
+StartServerFailed()
+{
+	struct display *d = startingServer;
+	if (!d->serverAttempts || d->startTries < d->serverAttempts) {
+		d->serverStatus = pausing;
+		serverTimeout = d->openDelay + now;
+	} else {
+		d->serverStatus = ignore;
+		serverTimeout = TO_INF;
+		startingServer = 0;
+		LogError( "X server for display %s can't be started,"
+		          " session disabled\n", d->name );
+		StopDisplay( d );
+	}
+}
+
+void
+StartServerTimeout()
+{
+	struct display *d = startingServer;
+	switch (d->serverStatus) {
+	case ignore:
+	case awaiting:
+		break; /* cannot happen */
+	case starting:
+		LogError( "X server startup timeout, terminating\n" );
+		kill( d->serverPid, d->termSignal );
+		d->serverStatus = d->termSignal == SIGKILL ? killed : terminated;
+		serverTimeout = d->serverTimeout + now;
+		break;
+	case terminated:
+		LogInfo( "X server termination timeout, killing\n" );
+		kill( d->serverPid, SIGKILL );
+		d->serverStatus = killed;
+		serverTimeout = 10 + now;
+		break;
+	case killed:
+		LogInfo( "X server is stuck in D state; leaving it alone\n" );
+		StartServerFailed();
+		break;
+	case pausing:
+		StartServerOnce();
+		break;
+	}
+}
+
+
+Display *dpy;
+
+/*
+ * this code is complicated by some TCP failings.  On
+ * many systems, the connect will occasionally hang forever,
+ * this trouble is avoided by setting up a timeout to Longjmp
+ * out of the connect (possibly leaving piles of garbage around
+ * inside Xlib) and give up, terminating the server.
+ */
+
+static Jmp_buf openAbort;
+
+/* ARGSUSED */
+static void
+abortOpen( int n ATTR_UNUSED )
+{
+	Longjmp( openAbort, 1 );
+}
+
+#ifdef XDMCP
+
+#ifdef STREAMSCONN
+# include <tiuser.h>
+#endif
+
+static void
+GetRemoteAddress( struct display *d, int fd )
+{
+	char buf[512];
+	int len = sizeof(buf);
+#ifdef STREAMSCONN
+	struct netbuf netb;
+#endif
+
+	XdmcpDisposeARRAY8( &d->peer );
+#ifdef STREAMSCONN
+	netb.maxlen = sizeof(buf);
+	netb.buf = buf;
+	t_getname( fd, &netb, REMOTENAME );
+	len = 8;
+	/* lucky for us, t_getname returns something that looks like a sockaddr */
+#else
+	getpeername( fd, (struct sockaddr *)buf, (void *)&len );
+#endif
+	if (len && XdmcpAllocARRAY8( &d->peer, len ))
+		memmove( (char *)d->peer.data, buf, len );
+	Debug( "got remote address %s %d\n", d->name, d->peer.length );
+}
+
+#endif /* XDMCP */
+
+static int
+openErrorHandler( Display *dspl ATTR_UNUSED )
+{
+	LogError( "IO Error in XOpenDisplay\n" );
+	exit( EX_OPENFAILED_DPY );
+	/*NOTREACHED*/
+	return (0);
+}
+
+void
+WaitForServer( struct display *d )
+{
+	volatile int i;
+	/* static int i; */
+
+	i = 0;
+	do {
+		(void)Signal( SIGALRM, abortOpen );
+		(void)alarm( (unsigned)d->openTimeout );
+		if (!Setjmp( openAbort )) {
+			Debug( "before XOpenDisplay(%s)\n", d->name );
+			errno = 0;
+			(void)XSetIOErrorHandler( openErrorHandler );
+			dpy = XOpenDisplay( d->name );
+#ifdef STREAMSCONN
+			{
+				/* For some reason, the next XOpenDisplay we do is
+				   going to fail, so we might as well get that out
+				   of the way.	There is something broken here. */
+				Display *bogusDpy = XOpenDisplay( d->name );
+				Debug( "bogus XOpenDisplay %s\n",
+				       bogusDpy ? "succeeded" : "failed" );
+				if (bogusDpy) XCloseDisplay( bogusDpy ); /* just in case */
+			}
+#endif
+			(void)alarm( (unsigned)0 );
+			(void)Signal( SIGALRM, SIG_DFL );
+			(void)XSetIOErrorHandler( (int (*)( Display * )) 0 );
+			Debug( "after XOpenDisplay(%s)\n", d->name );
+			if (dpy) {
+#ifdef XDMCP
+				if ((d->displayType & d_location) == dForeign)
+					GetRemoteAddress( d, ConnectionNumber( dpy ) );
+#endif
+				RegisterCloseOnFork( ConnectionNumber( dpy ) );
+				return;
+			}
+			Debug( "OpenDisplay(%s) attempt %d failed: %m\n", d->name, i + 1 );
+			sleep( (unsigned)d->openDelay );
+		} else {
+			LogError( "Hung in XOpenDisplay(%s), aborting\n", d->name );
+			(void)Signal( SIGALRM, SIG_DFL );
+			break;
+		}
+	} while (++i < d->openRepeat);
+	LogError( "Cannot connect to %s, giving up\n", d->name );
+	exit( EX_OPENFAILED_DPY );
+}
+
+
+void
+ResetServer( struct display *d )
+{
+	if (dpy && (d->displayType & d_origin) != dFromXDMCP)
+		pseudoReset();
+}
+
+
+static Jmp_buf pingTime;
+
+static void
+PingLost( void )
+{
+	Longjmp( pingTime, 1 );
+}
+
+/* ARGSUSED */
+static int
+PingLostIOErr( Display *dspl ATTR_UNUSED )
+{
+	PingLost();
+	return 0;
+}
+
+/* ARGSUSED */
+static void
+PingLostSig( int n ATTR_UNUSED )
+{
+	PingLost();
+}
+
+int
+PingServer( struct display *d )
+{
+	int (*oldError)( Display * );
+	void (*oldSig)( int );
+	int oldAlarm;
+
+	oldError = XSetIOErrorHandler( PingLostIOErr );
+	oldAlarm = alarm( 0 );
+	oldSig = Signal( SIGALRM, PingLostSig );
+	(void)alarm( d->pingTimeout * 60 );
+	if (!Setjmp( pingTime )) {
+		Debug( "ping X server\n" );
+		XSync( dpy, 0 );
+	} else {
+		Debug( "X server dead\n" );
+		(void)alarm( 0 );
+		(void)Signal( SIGALRM, SIG_DFL );
+		XSetIOErrorHandler( oldError );
+		return 0;
+	}
+	(void)alarm( 0 );
+	(void)Signal( SIGALRM, oldSig );
+	(void)alarm( oldAlarm );
+	Debug( "X server alive\n" );
+	XSetIOErrorHandler( oldError );
+	return 1;
+}