145 lines
3.9 KiB
C
145 lines
3.9 KiB
C
/* Copyright (C) 1996-2022 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 Lesser General Public
|
||
License as published by the Free Software Foundation; either
|
||
version 2.1 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
|
||
Lesser General Public License for more details.
|
||
|
||
You should have received a copy of the GNU Lesser General Public
|
||
License along with the GNU C Library; if not, see
|
||
<https://www.gnu.org/licenses/>. */
|
||
|
||
#include <assert.h>
|
||
#include <errno.h>
|
||
#include <limits.h>
|
||
#include <string.h>
|
||
#include <unistd.h>
|
||
#include <stdlib.h>
|
||
#include <utmp.h>
|
||
#include <shlib-compat.h>
|
||
|
||
/* Return the result of ttyname in the buffer pointed to by TTY, which should
|
||
be of length BUF_LEN. If it is too long to fit in this buffer, a
|
||
sufficiently long buffer is allocated using malloc, and returned in TTY.
|
||
0 is returned upon success, -1 otherwise. */
|
||
static int
|
||
tty_name (int fd, char **tty, size_t buf_len)
|
||
{
|
||
int rv; /* Return value. 0 = success. */
|
||
char *buf = *tty; /* Buffer for ttyname, initially the user's. */
|
||
|
||
for (;;)
|
||
{
|
||
char *new_buf;
|
||
|
||
if (buf_len)
|
||
{
|
||
rv = __ttyname_r (fd, buf, buf_len);
|
||
|
||
if (rv != 0 || memchr (buf, '\0', buf_len))
|
||
/* We either got an error, or we succeeded and the
|
||
returned name fit in the buffer. */
|
||
break;
|
||
|
||
/* Try again with a longer buffer. */
|
||
buf_len += buf_len; /* Double it */
|
||
}
|
||
else
|
||
/* No initial buffer; start out by mallocing one. */
|
||
buf_len = 128; /* First time guess. */
|
||
|
||
if (buf != *tty)
|
||
/* We've already malloced another buffer at least once. */
|
||
new_buf = realloc (buf, buf_len);
|
||
else
|
||
new_buf = malloc (buf_len);
|
||
if (! new_buf)
|
||
{
|
||
rv = -1;
|
||
__set_errno (ENOMEM);
|
||
break;
|
||
}
|
||
buf = new_buf;
|
||
}
|
||
|
||
if (rv == 0)
|
||
*tty = buf; /* Return buffer to the user. */
|
||
else if (buf != *tty)
|
||
free (buf); /* Free what we malloced when returning an error. */
|
||
|
||
return rv;
|
||
}
|
||
|
||
void
|
||
__login (const struct utmp *ut)
|
||
{
|
||
#ifdef PATH_MAX
|
||
char _tty[PATH_MAX + UT_LINESIZE];
|
||
#else
|
||
char _tty[512 + UT_LINESIZE];
|
||
#endif
|
||
char *tty = _tty;
|
||
int found_tty;
|
||
const char *ttyp;
|
||
struct utmp copy = *ut;
|
||
|
||
/* Fill in those fields we supply. */
|
||
copy.ut_type = USER_PROCESS;
|
||
copy.ut_pid = getpid ();
|
||
|
||
/* Seek tty. */
|
||
found_tty = tty_name (STDIN_FILENO, &tty, sizeof (_tty));
|
||
if (found_tty < 0)
|
||
found_tty = tty_name (STDOUT_FILENO, &tty, sizeof (_tty));
|
||
if (found_tty < 0)
|
||
found_tty = tty_name (STDERR_FILENO, &tty, sizeof (_tty));
|
||
|
||
if (found_tty >= 0)
|
||
{
|
||
/* We only want to insert the name of the tty without path.
|
||
But take care of name like /dev/pts/3. */
|
||
if (strncmp (tty, "/dev/", 5) == 0)
|
||
ttyp = tty + 5; /* Skip the "/dev/". */
|
||
else
|
||
ttyp = basename (tty);
|
||
|
||
/* Position to record for this tty. */
|
||
strncpy (copy.ut_line, ttyp, UT_LINESIZE);
|
||
|
||
/* Tell that we want to use the UTMP file. */
|
||
if (__utmpname (_PATH_UTMP) == 0)
|
||
{
|
||
/* Open UTMP file. */
|
||
__setutent ();
|
||
|
||
/* Write the entry. */
|
||
__pututline (©);
|
||
|
||
/* Close UTMP file. */
|
||
__endutent ();
|
||
}
|
||
|
||
if (tty != _tty)
|
||
free (tty); /* Free buffer malloced by tty_name. */
|
||
}
|
||
else
|
||
/* We provide a default value so that the output does not contain
|
||
an random bytes in this field. */
|
||
strncpy (copy.ut_line, "???", UT_LINESIZE);
|
||
|
||
/* Update the WTMP file. Here we have to add a new entry. */
|
||
__updwtmp (_PATH_WTMP, ©);
|
||
}
|
||
versioned_symbol (libc, __login, login, GLIBC_2_34);
|
||
libc_hidden_ver (__login, login)
|
||
|
||
#if OTHER_SHLIB_COMPAT (libutil, GLIBC_2_0, GLIBC_2_34)
|
||
compat_symbol (libutil, __login, login, GLIBC_2_0);
|
||
#endif
|