1 files changed, 80 insertions, 0 deletions
diff --git a/sysdeps/unix/getlogin_r.c b/sysdeps/unix/getlogin_r.c
new file mode 100644
index 0000000000..15afdee63c
--- /dev/null
+++ b/sysdeps/unix/getlogin_r.c
@@ -0,0 +1,80 @@
+/* Reentrant function to return the current login name.  Unix version.
+Copyright (C) 1991, 1992, 1996 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+
+The GNU C Library 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
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+#include <errno.h>
+#include <unistd.h>
+#include <string.h>
+#include <stdio.h>
+#include <limits.h>
+#include <fcntl.h>
+
+#include <utmp.h>
+
+/* Return at most NAME_LEN characters of the login name of the user in NAME.
+   If it cannot be determined or some other error occured, return the error
+   code.  Otherwise return 0.  */
+
+int
+getlogin_r (name, name_len)
+     char *name;
+     size_t name_len;
+{
+  char tty_pathname[2 + 2 * NAME_MAX];
+  char *real_tty_path = tty_pathname;
+  int result = 0;
+  struct utmp_data utmp_data;
+  struct utmp *ut;
+
+  {
+    int err;
+    int d = __open ("/dev/tty", 0);
+    if (d < 0)
+      return errno;
+
+    result = ttyname_r (d, real_tty_path, sizeof (tty_pathname));
+    err = errno;
+    (void) close (d);
+
+    if (result < 0)
+      {
+	errno = err;
+	return err;
+      }
+  }
+
+  real_tty_path += 5;		/* Remove "/dev/".  */
+
+  setutent_r (&utmp_data);
+  if (getutline_r (real_tty_path, &ut, &utmp_data) < 0)
+    {
+      if (errno == ESRCH)
+	/* The caller expects ENOENT if nothing is found.  */
+	result = ENOENT;
+      else
+	result = errno;
+    }
+  else
+    {
+      strncpy (name, ut->ut_line, name_len);
+      result = 0;
+    }
+  endutent_r (&utmp_data);
+
+  return result;
+}