glibc/sysdeps/unix/getlogin.c
Ulrich Drepper a3e59be8d1 Update.
Mon Aug 12 03:31:58 1996  Ulrich Drepper  <drepper@cygnus.com>

	* nss/nsswitch.c (__nss_configure_lookup):  New function.
	Allows to specify services.
	* nss/XXX-lookup.h: Rename database variable and make global.
	* nss/databases.def: New file.  Real names of all databases.

	* nss/nss.h: New file.  Contains declaration useful for users
	and service developers.
	* nss/nsswitch.h: Move some declarations to nss/nss.h.
	* nss.h: New file.  Wrapper around nss/nss.h.

	* nss/Makefile (headers): Add nss.h.
	(distributes): Add databases.h.

Sun Aug 11 16:19:42 1996  Ulrich Drepper  <drepper@cygnus.com>

	Help the poor people with fast machines by making sure only
	one `ar' commands works on the library.
	* autolock.sh: New file.  Written by Tom Tromey.
	* Makerules (do-ar): Call autolock.sh shell script instead of
	directly using `ar'.
	* config.make.in: Make configuration variable AUTOLOCK which
	gets initialized by configure.
	* configure.in: Define variable AUTOLOCK to point to autolock.sh
	script and mark it to substitute.

	* string/Makefile: Add -fno-builtin for tst-strlen.c, too.

	* elf/dl-lookup.c (_dl_lookup_symbol): Allow self-referencing.
	Patch by David Mosberger-Tang.

Sun Aug 11 01:12:38 1996  Richard Henderson  <rth@tamu.edu>

	* sysdeps/alpha/dl-machine.h (elf_alpha_fix_plt): Optimize LD_BIND_NOW
	startup by moving Icache flush from here ...
	(ELF_MACHINE_RUNTIME_TRAMPOLINE): ... to here.
	(ELF_MACHINE_USER_ADDRESS_MASK): Delete; it is unused.

	* sysdeps/alpha/divrem.h: Update comment to reflect the actual
	calling conventions.  The code is already correct.

Sun Aug 11 01:06:42 1996  Richard Henderson  <rth@tamu.edu>

	* string/Makefile: Compile tester with -fno-builtin as we want to
	test our implementations, not gcc's.
1996-08-12 01:42:37 +00:00

75 lines
2.4 KiB
C

/* 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 the login name of the user, or NULL if it can't be determined.
The returned pointer, if not NULL, is good only until the next call. */
char *
getlogin (void)
{
char tty_pathname[2 + 2 * NAME_MAX];
char *real_tty_path = tty_pathname;
char *result = NULL;
struct utmp_data utmp_data = { ut_fd: -1 };
static char name[UT_NAMESIZE + 1];
struct utmp *ut, line;
/* Get name of tty connected to fd 0. Return NULL if not a tty or
if fd 0 isn't open. Note that a lot of documentation says that
getlogin() is based on the controlling terminal---what they
really mean is "the terminal connected to standard input". The
getlogin() implementation of DEC Unix, SunOS, Solaris, HP-UX all
return NULL if fd 0 has been closed, so this is the compatible
thing to do. Note that ttyname(open("/dev/tty")) on those
systems returns /dev/tty, so that is not a possible solution for
getlogin(). */
if (__ttyname_r (0, real_tty_path, sizeof (tty_pathname)) < 0)
return NULL;
real_tty_path += 5; /* Remove "/dev/". */
__setutent_r (&utmp_data);
strncpy (line.ut_line, real_tty_path, sizeof line.ut_line);
if (__getutline_r (&line, &ut, &utmp_data) < 0)
{
if (errno == ESRCH)
/* The caller expects ENOENT if nothing is found. */
errno = ENOENT;
result = NULL;
}
else
{
strncpy (name, ut->ut_user, UT_NAMESIZE);
name[UT_NAMESIZE] = '\0';
result = name;
}
__endutent_r (&utmp_data);
return result;
}