(init_system_name): Use getaddrinfo if available.

2 files changed, 47 insertions, 1 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index 04fa6aa9357..cf1c42f73c9 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,5 +1,7 @@
 2007-11-18  Jan Dj,Ad(Brv  <jan.h.d@swipnet.se>
 
+        * sysdep.c (init_system_name): Use getaddrinfo if available.
+
         * xterm.c (x_scroll_bar_set_handle, x_scroll_bar_handle_click)
         (x_scroll_bar_note_movement): start, end, with, height in struct
         scroll_bar are integers and not Lisp_Object, so remove XINT for them.
diff --git a/src/sysdep.c b/src/sysdep.c
index 35a107f34cf..81850919dd3 100644
--- a/src/sysdep.c
+++ b/src/sysdep.c
@@ -2518,10 +2518,50 @@ init_system_name ()
 #endif /* not CANNOT_DUMP */
     if (! index (hostname, '.'))
       {
-        struct hostent *hp;
         int count;
+#ifdef HAVE_GETADDRINFO
+        struct addrinfo *res;
+        struct addrinfo hints;
+        int ret;
+
+        memset (&hints, 0, sizeof(hints));
+        hints.ai_socktype = SOCK_STREAM;
+        hints.ai_flags = AI_CANONNAME;
+
         for (count = 0;; count++)
           {
+            if ((ret = getaddrinfo (hostname, NULL, &hints, &res)) == 0
+                || ret != EAI_AGAIN)
+              break;
+
+            if (count >= 5)
+              break;
+            Fsleep_for (make_number (1), Qnil);
+          }
+
+        if (ret == 0)
+          {
+            struct addrinfo *it = res;
+            while (it)
+              {
+                char *fqdn = it->ai_canonname;
+                if (fqdn && index (fqdn, '.')
+                    && strcmp (fqdn, "localhost.localdomain") != 0)
+                  break;
+                it = it->ai_next;
+              }
+            if (it)
+              {
+                hostname = alloca (strlen (it->ai_canonname) + 1);
+                strcpy (hostname, it->ai_canonname);
+              }
+            freeaddrinfo (res);
+          }
+#else /* !HAVE_GETADDRINFO */
+        struct hostent *hp;
+        for (count = 0;; count++)
+          {
+
 #ifdef TRY_AGAIN
             h_errno = 0;
 #endif
@@ -2529,11 +2569,14 @@ init_system_name ()
 #ifdef TRY_AGAIN
             if (! (hp == 0 && h_errno == TRY_AGAIN))
 #endif
+
               break;
+
             if (count >= 5)
               break;
             Fsleep_for (make_number (1), Qnil);
           }
+
         if (hp)
           {
             char *fqdn = (char *) hp->h_name;
@@ -2567,6 +2610,7 @@ init_system_name ()
               }
 #endif
           }
+#endif /* !HAVE_GETADDRINFO */
       }
 #endif /* HAVE_SOCKETS */
   /* We used to try using getdomainname here,