X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fxgethostname.c;h=5178784baca5bffa889d7db3078a65f0b3f405e0;hb=a9b64ea6a96fe625db5332f5e2b3e5f968704af7;hp=d20967574dacb8cc536b36d69ec705604609b940;hpb=783c1624bd8b027a65b3fba57d3213ccb1a6ddbd;p=gnulib.git

diff --git a/lib/xgethostname.c b/lib/xgethostname.c
index d20967574..5178784ba 100644
--- a/lib/xgethostname.c
+++ b/lib/xgethostname.c
@@ -1,5 +1,5 @@
 /* xgethostname.c -- return current hostname with unlimited length
-   Copyright (C) 1992 Free Software Foundation, Inc.
+   Copyright (C) 1992, 1996, 2000, 2001, 2003 Free Software Foundation, Inc.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -15,39 +15,70 @@
    along with this program; if not, write to the Free Software Foundation,
    Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
 
-/* Written by Jim Meyering, meyering@comco.com */
+/* written by Jim Meyering */
 
 #ifdef HAVE_CONFIG_H
 # include <config.h>
 #endif
 
+#include <stdlib.h>
 #include <sys/types.h>
 
+#include <errno.h>
+#ifndef errno
+extern int errno;
+#endif
+
+#include "error.h"
+#include "xalloc.h"
+
+#ifndef ENAMETOOLONG
+# define ENAMETOOLONG 9999
+#endif
+
+#ifndef EXIT_FAILURE
+# define EXIT_FAILURE 1
+#endif
+
 int gethostname ();
-char *xmalloc ();
-char *xrealloc ();
 
 #ifndef INITIAL_HOSTNAME_LENGTH
-# define INITIAL_HOSTNAME_LENGTH 33
+# define INITIAL_HOSTNAME_LENGTH 34
 #endif
 
+/* Return the current hostname in malloc'd storage.
+   If malloc fails, exit.
+   Upon any other failure, return NULL.  */
 char *
 xgethostname ()
 {
   char *hostname;
   size_t size;
-  int err;
 
   size = INITIAL_HOSTNAME_LENGTH;
-  hostname = xmalloc (size);
+  /* Use size + 1 here rather than size to work around the bug
+     in SunOS 5.5's gethostname whereby it NUL-terminates HOSTNAME
+     even when the name is longer than the supplied buffer.  */
+  hostname = xmalloc (size + 1);
   while (1)
     {
-      hostname[size - 1] = '\0';
+      int k = size - 1;
+      int err;
+
+      errno = 0;
+      hostname[k] = '\0';
       err = gethostname (hostname, size);
-      if (err == 0 && hostname[size - 1] == '\0')
+      if (err >= 0 && hostname[k] == '\0')
 	break;
+      else if (err < 0 && errno != ENAMETOOLONG && errno != 0)
+	{
+	  int saved_errno = errno;
+	  free (hostname);
+	  errno = saved_errno;
+	  return NULL;
+	}
       size *= 2;
-      hostname = xrealloc (hostname, size);
+      hostname = xrealloc (hostname, size + 1);
     }
 
   return hostname;