/* Provide a working getlogin_r for systems which lack it.
- Copyright (C) 2005, 2006, 2007, 2009 Free Software Foundation, Inc.
+ Copyright (C) 2005-2007, 2010-2013 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
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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
+ along with this program; if not, see <http://www.gnu.org/licenses/>. */
-/* written by Paul Eggert and Derek Price */
+/* Written by Paul Eggert, Derek Price, and Bruno Haible. */
#include <config.h>
#include <errno.h>
#include <string.h>
-#if !HAVE_DECL_GETLOGIN
-char *getlogin (void);
+#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+# define WIN32_LEAN_AND_MEAN
+# include <windows.h>
+#else
+# if !HAVE_DECL_GETLOGIN
+extern char *getlogin (void);
+# endif
#endif
/* See unistd.in.h for documentation. */
int
getlogin_r (char *name, size_t size)
{
+#undef getlogin_r
+#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+ /* Native Windows platform. */
+ DWORD sz;
+
+ /* When size > 0x7fff, the doc says that GetUserName will fail.
+ Actually, on Windows XP SP3, it succeeds. But let's be safe,
+ for the sake of older Windows versions. */
+ if (size > 0x7fff)
+ size = 0x7fff;
+ sz = size;
+ if (!GetUserName (name, &sz))
+ {
+ if (GetLastError () == ERROR_INSUFFICIENT_BUFFER)
+ /* In this case, the doc says that sz contains the required size, but
+ actually, on Windows XP SP3, it contains 2 * the required size. */
+ return ERANGE;
+ else
+ return ENOENT;
+ }
+ return 0;
+#elif HAVE_GETLOGIN_R
+ /* Platform with a getlogin_r() function. */
+ int ret = getlogin_r (name, size);
+
+ if (ret == 0 && memchr (name, '\0', size) == NULL)
+ /* name contains a truncated result. */
+ return ERANGE;
+ return ret;
+#else
+ /* Platform with a getlogin() function. */
char *n;
size_t nlen;
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;
+ /* ENOENT is a reasonable errno value if getlogin returns NULL. */
+ return (errno != 0 ? errno : ENOENT);
+
nlen = strlen (n);
if (size <= nlen)
return ERANGE;
memcpy (name, n, nlen + 1);
return 0;
+#endif
}