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-rw-r--r--sysdeps/unix/getlogin_r.c80
1 files changed, 80 insertions, 0 deletions
diff --git a/sysdeps/unix/getlogin_r.c b/sysdeps/unix/getlogin_r.c
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--- /dev/null
+++ b/sysdeps/unix/getlogin_r.c
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+/* 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;
+}