Tests for module 'atexit'.

[gnulib.git] / lib / getlogin_r.c

diff --git a/lib/getlogin_r.c b/lib/getlogin_r.c
index c02db2f..bb89f6e 100644 (file)
--- a/lib/getlogin_r.c
+++ b/lib/getlogin_r.c
@@ -1,6 +1,6 @@
 /* Provide a working getlogin_r for systems which lack it.
 
-   Copyright (C) 2005 Free Software Foundation, Inc.
+   Copyright (C) 2005, 2006, 2007 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
@@ -18,24 +18,19 @@
 
 /* written by Paul Eggert and Derek Price */
 
-#if HAVE_CONFIG_H
-# include <config.h>
-#endif
+#include <config.h>
 
-#include "getlogin_r.h"
+/* Specification.  */
+#include <unistd.h>
 
 #include <errno.h>
 #include <string.h>
 
-#if HAVE_UNISTD_H
-# include <unistd.h>
-#endif
-
 #if !HAVE_DECL_GETLOGIN
 char *getlogin (void);
 #endif
 
-/* See getlogin_r.h for documentation.  */
+/* See unistd_.h for documentation.  */
 int
 getlogin_r (char *name, size_t size)
 {
@@ -44,8 +39,15 @@ getlogin_r (char *name, size_t size)
 
   errno = 0;
   n = getlogin ();
+
+  /* A system function like getlogin_r is never supposed to set errno
+     to zero, so make sure errno is nonzero here.  ENOENT is a
+     reasonable errno value if getlogin returns NULL.  */
+  if (!errno)
+    errno = ENOENT;
+
   if (!n)
-    return errno ? errno : ENOENT;
+    return errno;
   nlen = strlen (n);
   if (size <= nlen)
     return ERANGE;