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/* Copyright (C) 1996-2018 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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Contributed by Ulrich Drepper <drepper@cygnus.com>
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6c4009 |
and Paul Janzen <pcj@primenet.com>, 1996.
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6c4009 |
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The GNU C Library is free software; you can redistribute it and/or
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6c4009 |
modify it under the terms of the GNU Lesser General Public
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6c4009 |
License as published by the Free Software Foundation; either
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6c4009 |
version 2.1 of the License, or (at your option) any later version.
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6c4009 |
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6c4009 |
The GNU C Library is distributed in the hope that it will be useful,
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6c4009 |
but WITHOUT ANY WARRANTY; without even the implied warranty of
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6c4009 |
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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6c4009 |
Lesser General Public License for more details.
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6c4009 |
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6c4009 |
You should have received a copy of the GNU Lesser General Public
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6c4009 |
License along with the GNU C Library; if not, see
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6c4009 |
<http://www.gnu.org/licenses/>. */
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#include <assert.h>
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#include <errno.h>
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#include <fcntl.h>
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#include <signal.h>
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#include <stdbool.h>
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#include <stdio.h>
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#include <string.h>
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#include <unistd.h>
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#include <utmp.h>
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#include <not-cancel.h>
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#include <kernel-features.h>
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#include <sigsetops.h>
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#include <not-cancel.h>
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#include "utmp-private.h"
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#include "utmp-equal.h"
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/* Descriptor for the file and position. */
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static int file_fd = -1;
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static bool file_writable;
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static off64_t file_offset;
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/* Cache for the last read entry. */
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static struct utmp last_entry;
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bb02ec |
/* Returns true if *ENTRY matches last_entry, based on
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bb02ec |
data->ut_type. */
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bb02ec |
static bool
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bb02ec |
matches_last_entry (const struct utmp *data)
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bb02ec |
{
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bb02ec |
if (file_offset <= 0)
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bb02ec |
/* Nothing has been read. last_entry is stale and cannot match. */
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bb02ec |
return false;
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bb02ec |
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bb02ec |
if (data->ut_type == RUN_LVL
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bb02ec |
|| data->ut_type == BOOT_TIME
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bb02ec |
|| data->ut_type == OLD_TIME
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bb02ec |
|| data->ut_type == NEW_TIME)
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bb02ec |
/* For some entry types, only a type match is required. */
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bb02ec |
return data->ut_type == last_entry.ut_type;
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bb02ec |
else
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bb02ec |
/* For the process-related entries, a full match is needed. */
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bb02ec |
return __utmp_equal (&last_entry, data);
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bb02ec |
}
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/* Locking timeout. */
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#ifndef TIMEOUT
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# define TIMEOUT 10
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#endif
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/* Do-nothing handler for locking timeout. */
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static void timeout_handler (int signum) {};
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5f5648 |
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/* try_file_lock (LOCKING, FD, TYPE) returns true if the locking
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5f5648 |
operation failed and recovery needs to be performed.
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5f5648 |
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5f5648 |
file_unlock (FD) removes the lock (which must have been
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d20430 |
successfully acquired). */
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5f5648 |
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5f5648 |
static bool
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d20430 |
try_file_lock (int fd, int type)
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5f5648 |
{
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5f5648 |
/* Cancel any existing alarm. */
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d20430 |
int old_timeout = alarm (0);
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5f5648 |
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5f5648 |
/* Establish signal handler. */
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d20430 |
struct sigaction old_action;
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5f5648 |
struct sigaction action;
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5f5648 |
action.sa_handler = timeout_handler;
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5f5648 |
__sigemptyset (&action.sa_mask);
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5f5648 |
action.sa_flags = 0;
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d20430 |
__sigaction (SIGALRM, &action, &old_action);
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5f5648 |
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5f5648 |
alarm (TIMEOUT);
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5f5648 |
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5f5648 |
/* Try to get the lock. */
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fbc33e |
struct flock64 fl =
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5f5648 |
{
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5f5648 |
.l_type = type,
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f58b65 |
.l_whence = SEEK_SET,
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5f5648 |
};
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d20430 |
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d20430 |
bool status = __fcntl64_nocancel (fd, F_SETLKW, &fl) < 0;
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d20430 |
int saved_errno = errno;
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d20430 |
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d20430 |
/* Reset the signal handler and alarm. We must reset the alarm
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d20430 |
before resetting the handler so our alarm does not generate a
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d20430 |
spurious SIGALRM seen by the user. However, we cannot just set
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d20430 |
the user's old alarm before restoring the handler, because then
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d20430 |
it's possible our handler could catch the user alarm's SIGARLM and
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d20430 |
then the user would never see the signal he expected. */
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d20430 |
alarm (0);
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d20430 |
__sigaction (SIGALRM, &old_action, NULL);
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d20430 |
if (old_timeout != 0)
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d20430 |
alarm (old_timeout);
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d20430 |
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d20430 |
__set_errno (saved_errno);
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d20430 |
return status;
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5f5648 |
}
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5f5648 |
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5f5648 |
static void
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5f5648 |
file_unlock (int fd)
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5f5648 |
{
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fbc33e |
struct flock64 fl =
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5f5648 |
{
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5f5648 |
.l_type = F_UNLCK,
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5f5648 |
};
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5f5648 |
__fcntl64_nocancel (fd, F_SETLKW, &fl);
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5f5648 |
}
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5f5648 |
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#ifndef TRANSFORM_UTMP_FILE_NAME
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# define TRANSFORM_UTMP_FILE_NAME(file_name) (file_name)
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#endif
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2f694a |
int
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2f694a |
__libc_setutent (void)
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6c4009 |
{
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6c4009 |
if (file_fd < 0)
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{
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const char *file_name;
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6c4009 |
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file_name = TRANSFORM_UTMP_FILE_NAME (__libc_utmp_file_name);
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6c4009 |
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file_writable = false;
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file_fd = __open_nocancel
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(file_name, O_RDONLY | O_LARGEFILE | O_CLOEXEC);
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if (file_fd == -1)
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return 0;
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}
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__lseek64 (file_fd, 0, SEEK_SET);
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file_offset = 0;
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6c4009 |
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return 1;
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6c4009 |
}
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6c4009 |
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2f694a |
/* Preform initialization if necessary. */
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2f694a |
static bool
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2f694a |
maybe_setutent (void)
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2f694a |
{
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2f694a |
return file_fd >= 0 || __libc_setutent ();
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2f694a |
}
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6c4009 |
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809050 |
/* Reads the entry at file_offset, storing it in last_entry and
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Packit Service |
809050 |
updating file_offset on success. Returns -1 for a read error, 0
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809050 |
for EOF, and 1 for a successful read. last_entry and file_offset
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809050 |
are only updated on a successful and complete read. */
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809050 |
static ssize_t
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809050 |
read_last_entry (void)
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Packit Service |
809050 |
{
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Packit Service |
809050 |
struct utmp buffer;
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Packit Service |
809050 |
ssize_t nbytes = __pread64_nocancel (file_fd, &buffer, sizeof (buffer),
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Packit Service |
809050 |
file_offset);
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809050 |
if (nbytes < 0)
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809050 |
return -1;
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Packit Service |
809050 |
else if (nbytes != sizeof (buffer))
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809050 |
/* Assume EOF. */
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Packit Service |
809050 |
return 0;
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809050 |
else
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Packit Service |
809050 |
{
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Packit Service |
809050 |
last_entry = buffer;
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Packit Service |
809050 |
file_offset += sizeof (buffer);
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Packit Service |
809050 |
return 1;
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Packit Service |
809050 |
}
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Packit Service |
809050 |
}
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Packit Service |
809050 |
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2f694a |
int
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2f694a |
__libc_getutent_r (struct utmp *buffer, struct utmp **result)
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Packit Service |
82ff93 |
{
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Packit Service |
809050 |
int saved_errno = errno;
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Packit Service |
82ff93 |
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Packit Service |
809050 |
if (!maybe_setutent ())
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6c4009 |
{
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6c4009 |
/* Not available. */
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6c4009 |
*result = NULL;
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6c4009 |
return -1;
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6c4009 |
}
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6c4009 |
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d20430 |
if (try_file_lock (file_fd, F_RDLCK))
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Packit Service |
809050 |
return -1;
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Packit Service |
6de65a |
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Packit Service |
809050 |
ssize_t nbytes = read_last_entry ();
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Packit Service |
809050 |
file_unlock (file_fd);
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Packit Service |
809050 |
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Packit Service |
809050 |
if (nbytes <= 0) /* Read error or EOF. */
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6c4009 |
{
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Packit Service |
809050 |
if (nbytes == 0)
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Packit Service |
809050 |
/* errno should be unchanged to indicate success. A premature
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809050 |
EOF is treated like an EOF (missing complete record at the
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Packit Service |
809050 |
end). */
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Packit Service |
809050 |
__set_errno (saved_errno);
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6c4009 |
*result = NULL;
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Packit |
6c4009 |
return -1;
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Packit |
6c4009 |
}
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Packit |
6c4009 |
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6c4009 |
memcpy (buffer, &last_entry, sizeof (struct utmp));
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6c4009 |
*result = buffer;
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6c4009 |
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Packit |
6c4009 |
return 0;
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Packit |
6c4009 |
}
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Packit |
6c4009 |
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6c4009 |
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Packit Service |
a737ef |
/* Search for *ID, updating last_entry and file_offset. Return 0 on
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Packit Service |
93012f |
success and -1 on failure. Does not perform locking; for that see
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Packit Service |
93012f |
internal_getut_r below. */
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Packit |
6c4009 |
static int
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Packit Service |
93012f |
internal_getut_nolock (const struct utmp *id)
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Packit |
6c4009 |
{
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Packit Service |
bb02ec |
while (1)
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Packit |
6c4009 |
{
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Packit Service |
809050 |
ssize_t nbytes = read_last_entry ();
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Packit Service |
809050 |
if (nbytes < 0)
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Packit Service |
809050 |
return -1;
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Packit Service |
809050 |
if (nbytes == 0)
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Packit |
6c4009 |
{
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Packit Service |
809050 |
/* End of file reached. */
|
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Packit Service |
bb02ec |
__set_errno (ESRCH);
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Packit Service |
bb02ec |
return -1;
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Packit |
6c4009 |
}
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Packit Service |
6de65a |
|
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Packit Service |
bb02ec |
if (matches_last_entry (id))
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Packit Service |
bb02ec |
break;
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Packit |
6c4009 |
}
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Packit |
6c4009 |
|
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Packit Service |
93012f |
return 0;
|
|
Packit Service |
93012f |
}
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Packit |
6c4009 |
|
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Packit Service |
93012f |
/* Search for *ID, updating last_entry and file_offset. Return 0 on
|
|
Packit Service |
93012f |
success and -1 on failure. If the locking operation failed, write
|
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Packit Service |
93012f |
true to *LOCK_FAILED. */
|
|
Packit Service |
93012f |
static int
|
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Packit Service |
93012f |
internal_getut_r (const struct utmp *id, bool *lock_failed)
|
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Packit Service |
93012f |
{
|
|
Packit Service |
93012f |
if (try_file_lock (file_fd, F_RDLCK))
|
|
Packit Service |
93012f |
{
|
|
Packit Service |
93012f |
*lock_failed = true;
|
|
Packit Service |
93012f |
return -1;
|
|
Packit Service |
93012f |
}
|
|
Packit |
6c4009 |
|
|
Packit Service |
93012f |
int result = internal_getut_nolock (id);
|
|
Packit Service |
93012f |
file_unlock (file_fd);
|
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Packit |
6c4009 |
return result;
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|
Packit |
6c4009 |
}
|
|
Packit |
6c4009 |
|
|
Packit |
6c4009 |
/* For implementing this function we don't use the getutent_r function
|
|
Packit |
6c4009 |
because we can avoid the reposition on every new entry this way. */
|
|
Packit Service |
2f694a |
int
|
|
Packit Service |
2f694a |
__libc_getutid_r (const struct utmp *id, struct utmp *buffer,
|
|
Packit Service |
2f694a |
struct utmp **result)
|
|
Packit |
6c4009 |
{
|
|
Packit Service |
809050 |
if (!maybe_setutent ())
|
|
Packit |
6c4009 |
{
|
|
Packit |
6c4009 |
*result = NULL;
|
|
Packit |
6c4009 |
return -1;
|
|
Packit |
6c4009 |
}
|
|
Packit |
6c4009 |
|
|
Packit |
6c4009 |
/* We don't have to distinguish whether we can lock the file or
|
|
Packit |
6c4009 |
whether there is no entry. */
|
|
Packit |
6c4009 |
bool lock_failed = false;
|
|
Packit Service |
a737ef |
if (internal_getut_r (id, &lock_failed) < 0)
|
|
Packit |
6c4009 |
{
|
|
Packit |
6c4009 |
*result = NULL;
|
|
Packit |
6c4009 |
return -1;
|
|
Packit |
6c4009 |
}
|
|
Packit |
6c4009 |
|
|
Packit |
6c4009 |
memcpy (buffer, &last_entry, sizeof (struct utmp));
|
|
Packit |
6c4009 |
*result = buffer;
|
|
Packit |
6c4009 |
|
|
Packit |
6c4009 |
return 0;
|
|
Packit |
6c4009 |
}
|
|
Packit |
6c4009 |
|
|
Packit |
6c4009 |
/* For implementing this function we don't use the getutent_r function
|
|
Packit |
6c4009 |
because we can avoid the reposition on every new entry this way. */
|
|
Packit Service |
2f694a |
int
|
|
Packit Service |
2f694a |
__libc_getutline_r (const struct utmp *line, struct utmp *buffer,
|
|
Packit Service |
2f694a |
struct utmp **result)
|
|
Packit |
6c4009 |
{
|
|
Packit Service |
809050 |
if (!maybe_setutent ())
|
|
Packit |
6c4009 |
{
|
|
Packit |
6c4009 |
*result = NULL;
|
|
Packit |
6c4009 |
return -1;
|
|
Packit |
6c4009 |
}
|
|
Packit |
6c4009 |
|
|
Packit Service |
d20430 |
if (try_file_lock (file_fd, F_RDLCK))
|
|
Packit |
6c4009 |
{
|
|
Packit |
6c4009 |
*result = NULL;
|
|
Packit Service |
5f5648 |
return -1;
|
|
Packit |
6c4009 |
}
|
|
Packit |
6c4009 |
|
|
Packit |
6c4009 |
while (1)
|
|
Packit |
6c4009 |
{
|
|
Packit Service |
809050 |
ssize_t nbytes = read_last_entry ();
|
|
Packit Service |
809050 |
if (nbytes < 0)
|
|
Packit Service |
809050 |
{
|
|
Packit Service |
809050 |
file_unlock (file_fd);
|
|
Packit Service |
809050 |
*result = NULL;
|
|
Packit Service |
809050 |
return -1;
|
|
Packit Service |
809050 |
}
|
|
Packit Service |
809050 |
if (nbytes == 0)
|
|
Packit |
6c4009 |
{
|
|
Packit Service |
809050 |
/* End of file reached. */
|
|
Packit Service |
809050 |
file_unlock (file_fd);
|
|
Packit |
6c4009 |
__set_errno (ESRCH);
|
|
Packit |
6c4009 |
*result = NULL;
|
|
Packit Service |
809050 |
return -1;
|
|
Packit |
6c4009 |
}
|
|
Packit |
6c4009 |
|
|
Packit |
6c4009 |
/* Stop if we found a user or login entry. */
|
|
Packit Service |
c5ceb8 |
if ((last_entry.ut_type == USER_PROCESS
|
|
Packit |
6c4009 |
|| last_entry.ut_type == LOGIN_PROCESS)
|
|
Packit Service |
c5ceb8 |
&& (strncmp (line->ut_line, last_entry.ut_line, sizeof line->ut_line)
|
|
Packit Service |
c5ceb8 |
== 0))
|
|
Packit |
6c4009 |
break;
|
|
Packit |
6c4009 |
}
|
|
Packit |
6c4009 |
|
|
Packit Service |
809050 |
file_unlock (file_fd);
|
|
Packit |
6c4009 |
memcpy (buffer, &last_entry, sizeof (struct utmp));
|
|
Packit |
6c4009 |
*result = buffer;
|
|
Packit |
6c4009 |
|
|
Packit Service |
809050 |
return 0;
|
|
Packit |
6c4009 |
}
|
|
Packit |
6c4009 |
|
|
Packit |
6c4009 |
|
|
Packit Service |
2f694a |
struct utmp *
|
|
Packit Service |
2f694a |
__libc_pututline (const struct utmp *data)
|
|
Packit |
6c4009 |
{
|
|
Packit Service |
809050 |
if (!maybe_setutent ())
|
|
Packit Service |
2f694a |
return NULL;
|
|
Packit Service |
2f694a |
|
|
Packit |
6c4009 |
struct utmp *pbuf;
|
|
Packit Service |
6de65a |
|
|
Packit |
6c4009 |
if (! file_writable)
|
|
Packit |
6c4009 |
{
|
|
Packit |
6c4009 |
/* We must make the file descriptor writable before going on. */
|
|
Packit |
6c4009 |
const char *file_name = TRANSFORM_UTMP_FILE_NAME (__libc_utmp_file_name);
|
|
Packit |
6c4009 |
|
|
Packit |
6c4009 |
int new_fd = __open_nocancel
|
|
Packit |
6c4009 |
(file_name, O_RDWR | O_LARGEFILE | O_CLOEXEC);
|
|
Packit |
6c4009 |
if (new_fd == -1)
|
|
Packit |
6c4009 |
return NULL;
|
|
Packit |
6c4009 |
|
|
Packit Service |
809050 |
if (__dup2 (new_fd, file_fd) < 0)
|
|
Packit |
6c4009 |
{
|
|
Packit |
6c4009 |
__close_nocancel_nostatus (new_fd);
|
|
Packit |
6c4009 |
return NULL;
|
|
Packit |
6c4009 |
}
|
|
Packit |
6c4009 |
__close_nocancel_nostatus (new_fd);
|
|
Packit |
6c4009 |
file_writable = true;
|
|
Packit |
6c4009 |
}
|
|
Packit |
6c4009 |
|
|
Packit Service |
93012f |
/* Exclude other writers before validating the cache. */
|
|
Packit Service |
93012f |
if (try_file_lock (file_fd, F_WRLCK))
|
|
Packit Service |
93012f |
return NULL;
|
|
Packit Service |
93012f |
|
|
Packit |
6c4009 |
/* Find the correct place to insert the data. */
|
|
Packit Service |
93012f |
bool found = false;
|
|
Packit Service |
bb02ec |
if (matches_last_entry (data))
|
|
Packit |
6c4009 |
{
|
|
Packit Service |
809050 |
/* Read back the entry under the write lock. */
|
|
Packit Service |
809050 |
file_offset -= sizeof (last_entry);
|
|
Packit Service |
809050 |
ssize_t nbytes = read_last_entry ();
|
|
Packit Service |
809050 |
if (nbytes < 0)
|
|
Packit |
6c4009 |
{
|
|
Packit Service |
93012f |
file_unlock (file_fd);
|
|
Packit |
6c4009 |
return NULL;
|
|
Packit |
6c4009 |
}
|
|
Packit Service |
809050 |
|
|
Packit Service |
809050 |
if (nbytes == 0)
|
|
Packit Service |
809050 |
/* End of file reached. */
|
|
Packit Service |
809050 |
found = false;
|
|
Packit Service |
93012f |
else
|
|
Packit Service |
bb02ec |
found = matches_last_entry (data);
|
|
Packit |
6c4009 |
}
|
|
Packit |
6c4009 |
|
|
Packit Service |
93012f |
if (!found)
|
|
Packit Service |
809050 |
/* Search forward for the entry. */
|
|
Packit Service |
93012f |
found = internal_getut_nolock (data) >= 0;
|
|
Packit |
6c4009 |
|
|
Packit Service |
809050 |
off64_t write_offset;
|
|
Packit Service |
93012f |
if (!found)
|
|
Packit |
6c4009 |
{
|
|
Packit |
6c4009 |
/* We append the next entry. */
|
|
Packit Service |
809050 |
write_offset = __lseek64 (file_fd, 0, SEEK_END);
|
|
Packit Service |
809050 |
|
|
Packit Service |
809050 |
/* Round down to the next multiple of the entry size. This
|
|
Packit Service |
809050 |
ensures any partially-written record is overwritten by the
|
|
Packit Service |
809050 |
new record. */
|
|
Packit Service |
809050 |
write_offset = (write_offset / sizeof (struct utmp)
|
|
Packit Service |
809050 |
* sizeof (struct utmp));
|
|
Packit |
6c4009 |
}
|
|
Packit |
6c4009 |
else
|
|
Packit Service |
809050 |
/* Overwrite last_entry. */
|
|
Packit Service |
809050 |
write_offset = file_offset - sizeof (struct utmp);
|
|
Packit Service |
809050 |
|
|
Packit Service |
809050 |
/* Write the new data. */
|
|
Packit Service |
809050 |
ssize_t nbytes;
|
|
Packit Service |
809050 |
if (__lseek64 (file_fd, write_offset, SEEK_SET) < 0
|
|
Packit Service |
809050 |
|| (nbytes = __write_nocancel (file_fd, data, sizeof (struct utmp))) < 0)
|
|
Packit |
6c4009 |
{
|
|
Packit Service |
809050 |
/* There is no need to recover the file position because all
|
|
Packit Service |
809050 |
reads use pread64, and any future write is preceded by
|
|
Packit Service |
809050 |
another seek. */
|
|
Packit Service |
809050 |
file_unlock (file_fd);
|
|
Packit Service |
809050 |
return NULL;
|
|
Packit |
6c4009 |
}
|
|
Packit |
6c4009 |
|
|
Packit Service |
809050 |
if (nbytes != sizeof (struct utmp))
|
|
Packit |
6c4009 |
{
|
|
Packit |
6c4009 |
/* If we appended a new record this is only partially written.
|
|
Packit |
6c4009 |
Remove it. */
|
|
Packit Service |
93012f |
if (!found)
|
|
Packit Service |
809050 |
(void) __ftruncate64 (file_fd, write_offset);
|
|
Packit Service |
809050 |
file_unlock (file_fd);
|
|
Packit Service |
809050 |
/* Assume that the write failure was due to missing disk
|
|
Packit Service |
809050 |
space. */
|
|
Packit Service |
809050 |
__set_errno (ENOSPC);
|
|
Packit Service |
809050 |
return NULL;
|
|
Packit |
6c4009 |
}
|
|
Packit |
6c4009 |
|
|
Packit Service |
5f5648 |
file_unlock (file_fd);
|
|
Packit Service |
809050 |
file_offset = write_offset + sizeof (struct utmp);
|
|
Packit Service |
809050 |
pbuf = (struct utmp *) data;
|
|
Packit |
6c4009 |
|
|
Packit |
6c4009 |
return pbuf;
|
|
Packit |
6c4009 |
}
|
|
Packit |
6c4009 |
|
|
Packit |
6c4009 |
|
|
Packit Service |
2f694a |
void
|
|
Packit Service |
2f694a |
__libc_endutent (void)
|
|
Packit |
6c4009 |
{
|
|
Packit Service |
2f694a |
if (file_fd >= 0)
|
|
Packit Service |
2f694a |
{
|
|
Packit Service |
2f694a |
__close_nocancel_nostatus (file_fd);
|
|
Packit Service |
2f694a |
file_fd = -1;
|
|
Packit Service |
2f694a |
}
|
|
Packit |
6c4009 |
}
|
|
Packit |
6c4009 |
|
|
Packit |
6c4009 |
|
|
Packit Service |
2f694a |
int
|
|
Packit Service |
2f694a |
__libc_updwtmp (const char *file, const struct utmp *utmp)
|
|
Packit |
6c4009 |
{
|
|
Packit |
6c4009 |
int result = -1;
|
|
Packit |
6c4009 |
off64_t offset;
|
|
Packit |
6c4009 |
int fd;
|
|
Packit |
6c4009 |
|
|
Packit |
6c4009 |
/* Open WTMP file. */
|
|
Packit |
6c4009 |
fd = __open_nocancel (file, O_WRONLY | O_LARGEFILE);
|
|
Packit |
6c4009 |
if (fd < 0)
|
|
Packit |
6c4009 |
return -1;
|
|
Packit |
6c4009 |
|
|
Packit Service |
d20430 |
if (try_file_lock (fd, F_WRLCK))
|
|
Packit Service |
5f5648 |
{
|
|
Packit Service |
5f5648 |
__close_nocancel_nostatus (fd);
|
|
Packit Service |
5f5648 |
return -1;
|
|
Packit Service |
5f5648 |
}
|
|
Packit |
6c4009 |
|
|
Packit |
6c4009 |
/* Remember original size of log file. */
|
|
Packit |
6c4009 |
offset = __lseek64 (fd, 0, SEEK_END);
|
|
Packit |
6c4009 |
if (offset % sizeof (struct utmp) != 0)
|
|
Packit |
6c4009 |
{
|
|
Packit |
6c4009 |
offset -= offset % sizeof (struct utmp);
|
|
Packit |
6c4009 |
__ftruncate64 (fd, offset);
|
|
Packit |
6c4009 |
|
|
Packit |
6c4009 |
if (__lseek64 (fd, 0, SEEK_END) < 0)
|
|
Packit |
6c4009 |
goto unlock_return;
|
|
Packit |
6c4009 |
}
|
|
Packit |
6c4009 |
|
|
Packit |
6c4009 |
/* Write the entry. If we can't write all the bytes, reset the file
|
|
Packit |
6c4009 |
size back to the original size. That way, no partial entries
|
|
Packit |
6c4009 |
will remain. */
|
|
Packit |
6c4009 |
if (__write_nocancel (fd, utmp, sizeof (struct utmp))
|
|
Packit |
6c4009 |
!= sizeof (struct utmp))
|
|
Packit |
6c4009 |
{
|
|
Packit |
6c4009 |
__ftruncate64 (fd, offset);
|
|
Packit |
6c4009 |
goto unlock_return;
|
|
Packit |
6c4009 |
}
|
|
Packit |
6c4009 |
|
|
Packit |
6c4009 |
result = 0;
|
|
Packit |
6c4009 |
|
|
Packit |
6c4009 |
unlock_return:
|
|
Packit Service |
745861 |
file_unlock (fd);
|
|
Packit |
6c4009 |
|
|
Packit |
6c4009 |
/* Close WTMP file. */
|
|
Packit |
6c4009 |
__close_nocancel_nostatus (fd);
|
|
Packit |
6c4009 |
|
|
Packit |
6c4009 |
return result;
|
|
Packit |
6c4009 |
}
|