XOpenDisplay: save the correct display_name value

The X Test Suite's XDisplayString test checks the invariant
XDisplayString(XOpenDisplay(str)) == str.  The Xlib XOpenDisplay violates this
invariant by expanding str to the canonical form "host:display.scrn" (unless
HAVE_LAUNCHD is set and it starts with "/tmp/launch").  E.g., this expands ":1"
to ":1.0":

  400|26 1 1 19:26:41|IC Start
  200|26 1 19:26:41|TP Start
  520|26 1 00032625 1 1|VSW5TESTSUITE PURPOSE 1
  520|26 1 00032625 1 2|Assertion XDisplayString-1.(A)
  520|26 1 00032625 1 3|A call to XDisplayString returns the string that was used
  520|26 1 00032625 1 4|as the argument to the XOpenDisplay call that returned the
  520|26 1 00032625 1 5|value used as the display argument.
  520|26 1 00032625 1 6|METH: Open a connection using XOpenDisplay.
  520|26 1 00032625 1 7|METH: Obtain the display string using XDisplayString.
  520|26 1 00032625 1 8|METH: Verify that the value of the string is the parameter used in XOpenDisplay.
  520|26 1 00032625 1 9|METH: Close the display using XCloseDisplay.
  520|26 1 00032625 1 10|REPORT: XDisplayString() returned ":1.0" instead of ":1".
  220|26 1 1 19:26:41|FAIL
  410|26 1 1 19:26:41|IC End

Fix this by deleting all of the code to construct the canonical path and just
stashing a copy of the original display_name in dpy->display_name.

Signed-off-by: Aaron Plattner <aplattner@nvidia.com>
Reviewed-by: Jeremy Huddleston <jeremyhu@apple.com>

3 files changed, 13 insertions, 27 deletions

diff --git a/src/OpenDis.c b/src/OpenDis.c
index 8de95569..e568a30e 100644
--- a/src/OpenDis.c
+++ b/src/OpenDis.c
@@ -69,7 +69,6 @@ XOpenDisplay (
 	int j, k;			/* random iterator indexes */
 	char *display_name;		/* pointer to display name */
 	char *setup = NULL;		/* memory allocated at startup */
-	char *fullname = NULL;		/* expanded name of display */
 	int iscreen;			/* screen number */
 	xConnSetupPrefix prefix;	/* prefix information */
 	int vendorlen;			/* length of vendor string */
@@ -117,13 +116,17 @@ XOpenDisplay (
 		return(NULL);
 	}
 
+	if ((dpy->display_name = strdup(display_name)) == NULL) {
+		OutOfMemory(dpy);
+		return(NULL);
+	}
+
 /*
  * Call the Connect routine to get the transport connection object.
- * If NULL is returned, the connection failed. The connect routine
- * will set fullname to point to the expanded name.
+ * If NULL is returned, the connection failed.
  */
 
-	if(!_XConnectXCB(dpy, display, &fullname, &iscreen)) {
+	if(!_XConnectXCB(dpy, display, &iscreen)) {
 		/* Try falling back on other transports if no transport specified */
 		const char *slash = strrchr(display_name, '/');
 		if(slash == NULL) {
@@ -135,14 +138,13 @@ XOpenDisplay (
 			if(buf) {
 				for(s = protocols; buf && *s; s++) {
 					snprintf(buf, buf_size, "%s/%s", *s, display_name);
-					if(_XConnectXCB(dpy, buf, &fullname, &iscreen))
+					if(_XConnectXCB(dpy, buf, &iscreen))
 						goto fallback_success;
 				}
 				Xfree(buf);
 			}
 		}
 
-		dpy->display_name = fullname;
 		OutOfMemory(dpy);
 		return NULL;
 	}
@@ -152,7 +154,6 @@ fallback_success:
 	 * Initialize pointers to NULL so that XFreeDisplayStructure will
 	 * work if we run out of memory before we finish initializing.
 	 */
-	dpy->display_name	= fullname;
 	dpy->keysyms		= (KeySym *) NULL;
 	dpy->modifiermap	= NULL;
 	dpy->lock_meaning	= NoSymbol;
@@ -314,7 +315,7 @@ fallback_success:
 	if (!mask)
 	{
 	    fprintf (stderr, "Xlib: connection to \"%s\" invalid setup\n",
-		     fullname);
+		     dpy->display_name);
 	    OutOfMemory(dpy);
 	    return (NULL);
 	}
@@ -678,8 +679,7 @@ void _XFreeDisplayStructure(Display *dpy)
             Xfree ((char *)dpy->pixmap_format);
 	    }
 
-	if (dpy->display_name)
-	   Xfree (dpy->display_name);
+	free(dpy->display_name);
 	if (dpy->vendor)
 	   Xfree (dpy->vendor);
 
diff --git a/src/Xxcbint.h b/src/Xxcbint.h
index c8191620..1fa1a4d7 100644
--- a/src/Xxcbint.h
+++ b/src/Xxcbint.h
@@ -40,7 +40,7 @@ typedef struct _X11XCBPrivate {
 
 /* xcb_disp.c */
 
-int _XConnectXCB(Display *dpy, _Xconst char *display, char **fullnamep, int *screenp);
+int _XConnectXCB(Display *dpy, _Xconst char *display, int *screenp);
 void _XFreeX11XCBStructure(Display *dpy);
 
 #endif /* XXCBINT_H */
diff --git a/src/xcb_disp.c b/src/xcb_disp.c
index 690a6036..0fa40dea 100644
--- a/src/xcb_disp.c
+++ b/src/xcb_disp.c
@@ -54,11 +54,10 @@ void XSetAuthorization(char *name, int namelen, char *data, int datalen)
 	_XUnlockMutex(_Xglobal_lock);
 }
 
-int _XConnectXCB(Display *dpy, _Xconst char *display, char **fullnamep, int *screenp)
+int _XConnectXCB(Display *dpy, _Xconst char *display, int *screenp)
 {
 	char *host;
 	int n = 0;
-	int len;
 	xcb_connection_t *c;
 
 	dpy->fd = -1;
@@ -69,20 +68,7 @@ int _XConnectXCB(Display *dpy, _Xconst char *display, char **fullnamep, int *scr
 
 	if(!xcb_parse_display(display, &host, &n, screenp))
 		return 0;
-
-	len = strlen(host) + (1 + 20 + 1 + 20 + 1);
-	*fullnamep = Xmalloc(len);
-	if (!*fullnamep) {
-		free(host);
-		return 0;
-	}
-
-#ifdef HAVE_LAUNCHD
-	if(strncmp(host, "/tmp/launch", 11) == 0)
-		snprintf(*fullnamep, len, "%s:%d", host, n);
-	else
-#endif
-		snprintf(*fullnamep, len, "%s:%d.%d", host, n, *screenp);
+	/* host and n are unused, but xcb_parse_display requires them */
 	free(host);
 
 	_XLockMutex(_Xglobal_lock);