/*
* Copyright (c) 1983, 1988, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)syslog.c 8.4 (Berkeley) 3/18/94";
#endif /* LIBC_SCCS and not lint */
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/syslog.h>
#include <sys/uio.h>
#include <sys/un.h>
#include <netdb.h>
#include <errno.h>
#include <fcntl.h>
#include <paths.h>
#include <stdio.h>
#include <stdio_ext.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include <stdlib.h>
#include <libc-lock.h>
#include <signal.h>
#include <locale.h>
#include <stdarg.h>
#include <libio/iolibio.h>
#include <math_ldbl_opt.h>
#include <kernel-features.h>
#define ftell(s) _IO_ftell (s)
static int LogType = SOCK_DGRAM; /* type of socket connection */
static int LogFile = -1; /* fd for log */
static int connected; /* have done connect */
static int LogStat; /* status bits, set by openlog() */
static const char *LogTag; /* string to tag the entry with */
static int LogFacility = LOG_USER; /* default facility code */
static int LogMask = 0xff; /* mask of priorities to be logged */
extern char *__progname; /* Program name, from crt0. */
/* Define the lock. */
__libc_lock_define_initialized (static, syslog_lock)
static void openlog_internal(const char *, int, int);
static void closelog_internal(void);
#ifndef NO_SIGPIPE
static void sigpipe_handler (int);
#endif
#ifndef send_flags
# define send_flags 0
#endif
struct cleanup_arg
{
void *buf;
struct sigaction *oldaction;
};
static void
cancel_handler (void *ptr)
{
#ifndef NO_SIGPIPE
/* Restore the old signal handler. */
struct cleanup_arg *clarg = (struct cleanup_arg *) ptr;
if (clarg != NULL && clarg->oldaction != NULL)
__sigaction (SIGPIPE, clarg->oldaction, NULL);
#endif
/* Free the lock. */
__libc_lock_unlock (syslog_lock);
}
/*
* syslog, vsyslog --
* print message on log file; output is intended for syslogd(8).
*/
void
__syslog(int pri, const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
__vsyslog_chk(pri, -1, fmt, ap);
va_end(ap);
}
ldbl_hidden_def (__syslog, syslog)
ldbl_strong_alias (__syslog, syslog)
void
__syslog_chk(int pri, int flag, const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
__vsyslog_chk(pri, flag, fmt, ap);
va_end(ap);
}
void
__vsyslog_chk(int pri, int flag, const char *fmt, va_list ap)
{
struct tm now_tm;
time_t now;
int fd;
FILE *f;
char *buf = 0;
size_t bufsize = 0;
size_t msgoff;
#ifndef NO_SIGPIPE
struct sigaction action, oldaction;
int sigpipe;
#endif
int saved_errno = errno;
char failbuf[3 * sizeof (pid_t) + sizeof "out of memory []"];
#define INTERNALLOG LOG_ERR|LOG_CONS|LOG_PERROR|LOG_PID
/* Check for invalid bits. */
if (pri & ~(LOG_PRIMASK|LOG_FACMASK)) {
syslog(INTERNALLOG,
"syslog: unknown facility/priority: %x", pri);
pri &= LOG_PRIMASK|LOG_FACMASK;
}
/* Check priority against setlogmask values. */
if ((LOG_MASK (LOG_PRI (pri)) & LogMask) == 0)
return;
/* Set default facility if none specified. */
if ((pri & LOG_FACMASK) == 0)
pri |= LogFacility;
/* Build the message in a memory-buffer stream. */
f = __open_memstream (&buf, &bufsize);
if (f == NULL)
{
/* We cannot get a stream. There is not much we can do but
emitting an error messages. */
char numbuf[3 * sizeof (pid_t)];
char *nump;
char *endp = __stpcpy (failbuf, "out of memory [");
pid_t pid = __getpid ();
nump = numbuf + sizeof (numbuf);
/* The PID can never be zero. */
do
*--nump = '0' + pid % 10;
while ((pid /= 10) != 0);
endp = __mempcpy (endp, nump, (numbuf + sizeof (numbuf)) - nump);
*endp++ = ']';
*endp = '\0';
buf = failbuf;
bufsize = endp - failbuf;
msgoff = 0;
}
else
{
__fsetlocking (f, FSETLOCKING_BYCALLER);
fprintf (f, "<%d>", pri);
(void) time (&now);
f->_IO_write_ptr += __strftime_l (f->_IO_write_ptr,
f->_IO_write_end
- f->_IO_write_ptr,
"%h %e %T ",
__localtime_r (&now, &now_tm),
_nl_C_locobj_ptr);
msgoff = ftell (f);
if (LogTag == NULL)
LogTag = __progname;
if (LogTag != NULL)
__fputs_unlocked (LogTag, f);
if (LogStat & LOG_PID)
fprintf (f, "[%d]", (int) __getpid ());
if (LogTag != NULL)
{
__putc_unlocked (':', f);
__putc_unlocked (' ', f);
}
/* Restore errno for %m format. */
__set_errno (saved_errno);
/* We have the header. Print the user's format into the
buffer. */
if (flag == -1)
vfprintf (f, fmt, ap);
else
__vfprintf_chk (f, flag, fmt, ap);
/* Close the memory stream; this will finalize the data
into a malloc'd buffer in BUF. */
fclose (f);
}
/* Output to stderr if requested. */
if (LogStat & LOG_PERROR) {
struct iovec iov[2];
struct iovec *v = iov;
v->iov_base = buf + msgoff;
v->iov_len = bufsize - msgoff;
/* Append a newline if necessary. */
if (buf[bufsize - 1] != '\n')
{
++v;
v->iov_base = (char *) "\n";
v->iov_len = 1;
}
__libc_cleanup_push (free, buf == failbuf ? NULL : buf);
/* writev is a cancellation point. */
(void)__writev(STDERR_FILENO, iov, v - iov + 1);
__libc_cleanup_pop (0);
}
/* Prepare for multiple users. We have to take care: open and
write are cancellation points. */
struct cleanup_arg clarg;
clarg.buf = buf;
clarg.oldaction = NULL;
__libc_cleanup_push (cancel_handler, &clarg);
__libc_lock_lock (syslog_lock);
#ifndef NO_SIGPIPE
/* Prepare for a broken connection. */
memset (&action, 0, sizeof (action));
action.sa_handler = sigpipe_handler;
sigemptyset (&action.sa_mask);
sigpipe = __sigaction (SIGPIPE, &action, &oldaction);
if (sigpipe == 0)
clarg.oldaction = &oldaction;
#endif
/* Get connected, output the message to the local logger. */
if (!connected)
openlog_internal(LogTag, LogStat | LOG_NDELAY, 0);
/* If we have a SOCK_STREAM connection, also send ASCII NUL as
a record terminator. */
if (LogType == SOCK_STREAM)
++bufsize;
if (!connected || __send(LogFile, buf, bufsize, send_flags) < 0)
{
if (connected)
{
/* Try to reopen the syslog connection. Maybe it went
down. */
closelog_internal ();
openlog_internal(LogTag, LogStat | LOG_NDELAY, 0);
}
if (!connected || __send(LogFile, buf, bufsize, send_flags) < 0)
{
closelog_internal (); /* attempt re-open next time */
/*
* Output the message to the console; don't worry
* about blocking, if console blocks everything will.
* Make sure the error reported is the one from the
* syslogd failure.
*/
if (LogStat & LOG_CONS &&
(fd = __open(_PATH_CONSOLE, O_WRONLY|O_NOCTTY, 0)) >= 0)
{
__dprintf (fd, "%s\r\n", buf + msgoff);
(void)__close(fd);
}
}
}
#ifndef NO_SIGPIPE
if (sigpipe == 0)
__sigaction (SIGPIPE, &oldaction, (struct sigaction *) NULL);
#endif
/* End of critical section. */
__libc_cleanup_pop (0);
__libc_lock_unlock (syslog_lock);
if (buf != failbuf)
free (buf);
}
libc_hidden_def (__vsyslog_chk)
void
__vsyslog(int pri, const char *fmt, va_list ap)
{
__vsyslog_chk (pri, -1, fmt, ap);
}
ldbl_hidden_def (__vsyslog, vsyslog)
ldbl_weak_alias (__vsyslog, vsyslog)
static struct sockaddr_un SyslogAddr; /* AF_UNIX address of local logger */
static void
openlog_internal(const char *ident, int logstat, int logfac)
{
if (ident != NULL)
LogTag = ident;
LogStat = logstat;
if (logfac != 0 && (logfac &~ LOG_FACMASK) == 0)
LogFacility = logfac;
int retry = 0;
while (retry < 2) {
if (LogFile == -1) {
SyslogAddr.sun_family = AF_UNIX;
(void)strncpy(SyslogAddr.sun_path, _PATH_LOG,
sizeof(SyslogAddr.sun_path));
if (LogStat & LOG_NDELAY) {
LogFile = __socket(AF_UNIX, LogType | SOCK_CLOEXEC, 0);
if (LogFile == -1)
return;
}
}
if (LogFile != -1 && !connected)
{
int old_errno = errno;
if (__connect(LogFile, &SyslogAddr, sizeof(SyslogAddr))
== -1)
{
int saved_errno = errno;
int fd = LogFile;
LogFile = -1;
(void)__close(fd);
__set_errno (old_errno);
if (saved_errno == EPROTOTYPE)
{
/* retry with the other type: */
LogType = (LogType == SOCK_DGRAM
? SOCK_STREAM : SOCK_DGRAM);
++retry;
continue;
}
} else
connected = 1;
}
break;
}
}
void
openlog (const char *ident, int logstat, int logfac)
{
/* Protect against multiple users and cancellation. */
__libc_cleanup_push (cancel_handler, NULL);
__libc_lock_lock (syslog_lock);
openlog_internal (ident, logstat, logfac);
__libc_cleanup_pop (1);
}
#ifndef NO_SIGPIPE
static void
sigpipe_handler (int signo)
{
closelog_internal ();
}
#endif
static void
closelog_internal (void)
{
if (!connected)
return;
__close (LogFile);
LogFile = -1;
connected = 0;
}
void
closelog (void)
{
/* Protect against multiple users and cancellation. */
__libc_cleanup_push (cancel_handler, NULL);
__libc_lock_lock (syslog_lock);
closelog_internal ();
LogTag = NULL;
LogType = SOCK_DGRAM; /* this is the default */
/* Free the lock. */
__libc_cleanup_pop (1);
}
/* setlogmask -- set the log mask level */
int
setlogmask (int pmask)
{
int omask;
omask = LogMask;
if (pmask != 0)
LogMask = pmask;
return (omask);
}