Bug 8014: xdm should set the WINDOWPATH environment variable

X.Org Bug #8014: <https://bugs.freedesktop.org/show_bug.cgi?id=8014>
Patch #6702: <https://bugs.freedesktop.org/attachment.cgi?id=6702>

5 files changed, 93 insertions, 10 deletions

diff --git a/dm.c b/dm.c
index 80a295a..52b49eb 100644
--- a/dm.c
+++ b/dm.c
@@ -68,7 +68,9 @@ from The Open Group.
 # include	<sys/stat.h>
 # include	<errno.h>
 # include	<X11/Xfuncproto.h>
+# include	<X11/Xatom.h>
 # include	<stdarg.h>
+# include	<stdint.h>
 
 #ifndef F_TLOCK
 #ifndef X_NOT_POSIX
@@ -622,6 +624,78 @@ StartDisplays (void)
     ForEachDisplay (CheckDisplayStatus);
 }
 
+static void
+SetWindowPath(struct display *d)
+{
+	/* setting WINDOWPATH for clients */
+	Atom prop;
+	Atom actualtype;
+	int actualformat;
+	unsigned long nitems;
+	unsigned long bytes_after;
+	unsigned char *buf;
+	const char *windowpath;
+	char *newwindowpath;
+	unsigned long num;
+	char nums[10];
+	int numn;
+
+	prop = XInternAtom(d->dpy, "XFree86_VT", False);
+	if (prop == None) {
+		fprintf(stderr, "no XFree86_VT atom\n");
+		return;
+	}
+	if (XGetWindowProperty(d->dpy, DefaultRootWindow(d->dpy), prop, 0, 1, 
+		False, AnyPropertyType, &actualtype, &actualformat, 
+		&nitems, &bytes_after, &buf)) {
+		fprintf(stderr, "no XFree86_VT property\n");
+		return;
+	}
+	if (nitems != 1) {
+		fprintf(stderr, "%lu items in XFree86_VT property!\n", nitems);
+		XFree(buf);
+		return;
+	}
+	switch (actualtype) {
+	case XA_CARDINAL:
+	case XA_INTEGER:
+	case XA_WINDOW:
+		switch (actualformat) {
+		case  8:
+			num = (*(uint8_t  *)(void *)buf);
+			break;
+		case 16:
+			num = (*(uint16_t *)(void *)buf);
+			break;
+		case 32:
+			num = (*(uint32_t *)(void *)buf);
+			break;
+		default:
+			fprintf(stderr, "format %d in XFree86_VT property!\n", actualformat);
+			XFree(buf);
+			return;
+		}
+		break;
+	default:
+		fprintf(stderr, "type %lx in XFree86_VT property!\n", actualtype);
+		XFree(buf);
+		return;
+	}
+	XFree(buf);
+	windowpath = getenv("WINDOWPATH");
+	numn = snprintf(nums, sizeof(nums), "%lu", num);
+	if (!windowpath) {
+		newwindowpath = malloc(numn + 1);
+		sprintf(newwindowpath, "%s", nums);
+	} else {
+		newwindowpath = malloc(strlen(windowpath) + 1 + numn + 1);
+		sprintf(newwindowpath, "%s:%s", windowpath, nums);
+	}
+	if (d->windowPath)
+		free(d->windowPath);
+	d->windowPath = newwindowpath;
+}
+
 void
 StartDisplay (struct display *d)
 {
@@ -677,6 +751,7 @@ StartDisplay (struct display *d)
 	SetAuthorization (d);
 	if (!WaitForServer (d))
 	    exit (OPENFAILED_DISPLAY);
+	SetWindowPath(d);
 #ifdef XDMCP
 	if (d->useChooser)
 	    RunChooser (d);
diff --git a/dm.h b/dm.h
index e8b8df8..5fa13e4 100644
--- a/dm.h
+++ b/dm.h
@@ -242,6 +242,8 @@ struct display {
 
 	/* Hack for making "Willing to manage" configurable */
 	char		*willing;	/* "Willing to manage" program */
+	Display		*dpy;		/* Display */
+	char		*windowPath;	/* path to server "window" */
 };
 
 #ifdef XDMCP
diff --git a/server.c b/server.c
index 2f991ae..aa6fdb1 100644
--- a/server.c
+++ b/server.c
@@ -51,8 +51,6 @@ static int receivedUsr1;
 
 static int serverPause (unsigned t, pid_t serverPid);
 
-static Display	*dpy;
-
 /* ARGSUSED */
 static SIGVAL
 CatchUsr1 (int n)
@@ -304,7 +302,7 @@ WaitForServer (struct display *d)
 	    Debug ("Before XOpenDisplay(%s)\n", d->name);
 	    errno = 0;
 	    (void) XSetIOErrorHandler (openErrorHandler);
-	    dpy = XOpenDisplay (d->name);
+	    d->dpy = XOpenDisplay (d->name);
 #ifdef STREAMSCONN
 	    {
 		/* For some reason, the next XOpenDisplay we do is
@@ -320,13 +318,13 @@ WaitForServer (struct display *d)
 	    (void) Signal (SIGALRM, SIG_DFL);
 	    (void) XSetIOErrorHandler ((int (*)(Display *)) 0);
 	    Debug ("After XOpenDisplay(%s)\n", d->name);
-	    if (dpy) {
+	    if (d->dpy) {
 #ifdef XDMCP
 	    	if (d->displayType.location == Foreign)
-		    GetRemoteAddress (d, ConnectionNumber (dpy));
+		    GetRemoteAddress (d, ConnectionNumber (d->dpy));
 #endif
-	    	RegisterCloseOnFork (ConnectionNumber (dpy));
-		(void) fcntl (ConnectionNumber (dpy), F_SETFD, 0);
+	    	RegisterCloseOnFork (ConnectionNumber (d->dpy));
+		(void) fcntl (ConnectionNumber (d->dpy), F_SETFD, 0);
 	    	return 1;
 	    } else {
 	    	Debug ("OpenDisplay failed %d (%s) on \"%s\"\n",
@@ -349,8 +347,8 @@ WaitForServer (struct display *d)
 void
 ResetServer (struct display *d)
 {
-    if (dpy && d->displayType.origin != FromXDMCP)
-	pseudoReset (dpy);
+    if (d->dpy && d->displayType.origin != FromXDMCP)
+	pseudoReset (d->dpy);
 }
 
 static Jmp_buf	pingTime;
@@ -384,7 +382,7 @@ PingServer (struct display *d, Display *alternateDpy)
     int	    oldAlarm;
     static Display *aDpy;
     
-    aDpy = (alternateDpy != NULL ? alternateDpy : dpy);
+    aDpy = (alternateDpy != NULL ? alternateDpy : d->dpy);
     oldError = XSetIOErrorHandler (PingLostIOErr);
     oldAlarm = alarm (0);
     oldSig = Signal (SIGALRM, PingLostSig);
diff --git a/session.c b/session.c
index 7aaeeaa..384fd78 100644
--- a/session.c
+++ b/session.c
@@ -769,6 +769,10 @@ StartClient (
 	}
 #endif /* K5AUTH */
 #endif /* !USE_PAM */
+
+	if (d->windowPath)
+		verify->userEnviron = setEnv(verify->userEnviron, "WINDOWPATH", d->windowPath);
+
 	if (passwd != NULL)
 	    bzero(passwd, strlen(passwd));
 
@@ -961,6 +965,8 @@ systemEnv (struct display *d, char *user, char *home)
     env = setEnv (env, "SHELL", d->systemShell);
     if (d->authFile)
 	    env = setEnv (env, "XAUTHORITY", d->authFile);
+    if (d->windowPath)
+	    env = setEnv (env, "WINDOWPATH", d->windowPath);
     return env;
 }
 
diff --git a/xdm.man.cpp b/xdm.man.cpp
index c42e253..2e51cbf 100644
--- a/xdm.man.cpp
+++ b/xdm.man.cpp
@@ -1092,6 +1092,7 @@ the following environment variables are passed:
 	PATH	the value of \fBDisplayManager.\fP\fIDISPLAY\fP\fB.systemPath\fP
 	SHELL	the value of \fBDisplayManager.\fP\fIDISPLAY\fP\fB.systemShell\fP
 	XAUTHORITY	may be set to an authority file
+	WINDOWPATH	may be set to the "window path" leading to the X server
 
 .fi
 .PP
@@ -1146,6 +1147,7 @@ the following environment variables are passed:
 	SHELL	the user's default shell (from \fIgetpwnam\fP)
 	XAUTHORITY	may be set to a non-standard authority file
 	KRB5CCNAME	may be set to a Kerberos credentials cache name
+	WINDOWPATH	may be set to the "window path" leading to the X server
 
 .fi
 .PP