From 455d862774b791f4ca93f9885e1e899208a5080c Mon Sep 17 00:00:00 2001
From: Jeremy Huddleston Sequoia <jeremyhu@apple.com>
Date: Sat, 10 Sep 2016 22:32:56 -0700
Subject: [PATCH 3/3] os/connection: Improve abstraction for launchd secure
 sockets

This changes away from hard-coding the /tmp/launch-* path to now
supporting a generic <path to unix socket>[.<screen>] format for
$DISPLAY.

cf-libxcb: d978a4f69b30b630f28d07f1003cf290284d24d8

Signed-off-by: Jeremy Huddleston Sequoia <jeremyhu@apple.com>
---
 os/connection.c | 31 ++++++++++++++++++++++++++-----
 1 file changed, 26 insertions(+), 5 deletions(-)

diff --git a/os/connection.c b/os/connection.c
index a901ebf..ac7d12b 100644
--- a/os/connection.c
+++ b/os/connection.c
@@ -79,6 +79,8 @@ SOFTWARE.
 #include <stdio.h>
 #include <stdlib.h>
 
+#include <sys/stat.h>
+
 #ifndef WIN32
 #include <sys/socket.h>
 
@@ -1267,15 +1269,34 @@
 void
 ListenOnOpenFD(int fd, int noxauth)
 {
-    char port[256];
+    char port[PATH_MAX];
     XtransConnInfo ciptr;
     const char *display_env = getenv("DISPLAY");
 
-    if (display_env && (strncmp(display_env, "/tmp/launch", 11) == 0)) {
-        /* Make the path the launchd socket if our DISPLAY is set right */
-        strcpy(port, display_env);
+    /* First check if display_env matches a <path to unix socket>[.<screen number>] scheme (eg: launchd) */
+    if (display_env) {
+        struct stat sbuf;
+
+        strlcpy(port, display_env, sizeof(port));
+
+        /* If the path exists, we don't have do do anything else.
+         * If it doesn't, we need to check for a .<screen number> to strip off and recheck.
+         */
+        if (0 != stat(port, &sbuf)) {
+            char *dot = strrchr(port, '.');
+            if (dot) {
+                *dot = '\0';
+
+                if (0 != stat(port, &sbuf)) {
+                    display_env = NULL;
+                }
+            } else {
+                display_env = NULL;
+            }
+        }
     }
-    else {
+
+    if (!display_env) {
         /* Just some default so things don't break and die. */
         snprintf(port, sizeof(port), ":%d", atoi(display));
     }
-- 
2.9.3