2 files changed, 79 insertions, 27 deletions

diff --git a/mailbox/locker.c b/mailbox/locker.c
index f752c1661..4f0dcf215 100644
--- a/mailbox/locker.c
+++ b/mailbox/locker.c
@@ -704,14 +704,11 @@ destroy_dotlock (mu_locker_t locker)
   free (locker->data.dot.nfslock);
 }
 
-#ifndef MAXHOSTNAMELEN
-# define MAXHOSTNAMELEN 256
-#endif
-
 static int
 lock_dotlock (mu_locker_t locker, enum mu_locker_mode mode)
 {
-  char host[MAXHOSTNAMELEN + 1] = "localhost";
+  int rc;
+  char *host = NULL;
   char pid[11];		/* 10 is strlen(2^32 = 4294967296) */
   char now[11];
   size_t sz = 0;
@@ -729,8 +726,9 @@ lock_dotlock (mu_locker_t locker, enum mu_locker_mode mode)
 
   /* build the NFS hitching-post to the lock file */
 
-  gethostname (host, sizeof (host));
-  host[MAXHOSTNAMELEN] = 0;
+  rc = mu_get_host_name (&host);
+  if (rc)
+    return rc;
 
   snprintf (now, sizeof (now), "%lu", (unsigned long) time (0));
   now[sizeof (now) - 1] = 0;
@@ -746,10 +744,14 @@ lock_dotlock (mu_locker_t locker, enum mu_locker_mode mode)
   locker->data.dot.nfslock = malloc (sz);
   
   if (!locker->data.dot.nfslock)
-    return ENOMEM;
-  
+    {
+      free (host);
+      return ENOMEM;
+    }
+
   snprintf (locker->data.dot.nfslock, sz, "%s.%s.%s.%s",
 	    locker->file, pid, now, host);
+  free (host);
   
   fd = open (locker->data.dot.nfslock,
 	     O_WRONLY | O_CREAT | O_EXCL, LOCKFILE_ATTR);
diff --git a/mailbox/mutil.c b/mailbox/mutil.c
index 656a31f19..5e2691d97 100644
--- a/mailbox/mutil.c
+++ b/mailbox/mutil.c
@@ -291,30 +291,80 @@ mu_cpystr (char *dst, const char *src, size_t size)
   return len;
 }
 
+#ifndef MAXHOSTNAMELEN
+# define MAXHOSTNAMELEN 64
+#endif
+
 int
 mu_get_host_name (char **host)
 {
-  char hostname[MAXHOSTNAMELEN + 1];
-  struct hostent *hp = NULL;
-  char *domain = NULL;
-
-  gethostname (hostname, sizeof hostname);
-  hostname[sizeof (hostname) - 1] = 0;
-
-  if ((hp = gethostbyname (hostname)))
-    domain = hp->h_name;
-  else
-    domain = hostname;
-
-  domain = strdup (domain);
-
-  if (!domain)
-    return ENOMEM;
+  char *hostname = NULL;
+  size_t size = 0;
+  char *p;
 
-  *host = domain;
+  while (1)
+    {
+      if (size == 0)
+	{
+	  size = MAXHOSTNAMELEN;
+	  p = malloc (size);
+	}
+      else
+	{
+	  size_t ns = size * 2;
+	  if (ns < size)
+	    {
+	      free (hostname);
+	      return ENOMEM;
+	    }
+	  size = ns;
+	  p = realloc (hostname, size);
+	}
+      if (!p)
+	{
+	  free (hostname);
+	  return ENOMEM;
+	}
+      hostname = p;
+      hostname[size - 1] = 0;
+      if (gethostname (hostname, size - 1) == 0)
+	{
+	  if (!hostname[size - 1])
+	    break;
+	}
+      else if (errno != 0 && errno != ENAMETOOLONG && errno != EINVAL
+	       && errno != ENOMEM)
+	{
+	  int rc = errno;
+	  free (hostname);
+	  return rc;
+	}
+    }
 
+  /* Try to return fully qualified host name */
+  if (!strchr (hostname, '.'))
+    {
+      struct hostent *hp = gethostbyname (hostname);
+      if (hp)
+	{
+	  size_t len = strlen (hp->h_name);
+	  if (size < len + 1)
+	    {
+	      p = realloc (hostname, len + 1);
+	      if (!p)
+		{
+		  free (hostname);
+		  return ENOMEM;
+		}
+	      hostname = p;
+	    }
+	  strcpy (hostname, hp->h_name);
+	}
+    }
+  
+  *host = hostname;
   return 0;
-}
+}  
 
 /*
  * Functions used to convert unix mailbox/user names into RFC822 addr-specs.