xalloc.h now uses inline, so includers need to configure this.

[gnulib.git] / lib / xgethostname.c

diff --git a/lib/xgethostname.c b/lib/xgethostname.c
index f00d7bd..1f4d728 100644 (file)
--- a/lib/xgethostname.c
+++ b/lib/xgethostname.c
@@ -1,28 +1,84 @@
+/* xgethostname.c -- return current hostname with unlimited length
+   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
+   the Free Software Foundation; either version 2, or (at your option)
+   any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   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 */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+/* Specification.  */
+#include "xgethostname.h"
+
+#include <stdlib.h>
 #include <sys/types.h>
 
+#include <errno.h>
+#ifndef errno
+extern int errno;
+#endif
+
+#include "error.h"
+#include "exit.h"
+#include "xalloc.h"
+
+#ifndef ENAMETOOLONG
+# define ENAMETOOLONG 9999
+#endif
+
 int gethostname ();
-char *xmalloc ();
-char *xrealloc ();
 
-#define INITIAL_HOSTNAME_LENGTH 33
+#ifndef INITIAL_HOSTNAME_LENGTH
+# 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 ()
+xgethostname (void)
 {
   char *hostname;
   size_t size;
-  int err;
 
   size = INITIAL_HOSTNAME_LENGTH;
+  /* 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 = xmalloc (size);
-      hostname[size - 1] = '\0';
+      int k = size - 1;
+      int err;
+
+      errno = 0;
+      hostname[k] = '\0';
       err = gethostname (hostname, size);
-      if (err || 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;