* Copyright (c) 1983, 1988, 1993

/* $NetBSD: syslog.c,v 1.58 2017/01/12 18:16:52 christos Exp $ */

/*
* 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.
* 3. 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.
*/

#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
#if 0
static char sccsid[] = "@(#)syslog.c 8.5 (Berkeley) 4/29/95";
#else
__RCSID("$NetBSD: syslog.c,v 1.58 2017/01/12 18:16:52 christos Exp $");
#endif
#endif /* LIBC_SCCS and not lint */

#include "namespace.h"
#include <sys/types.h>
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/syslog.h>
#include <sys/uio.h>
#include <sys/un.h>
#include <netdb.h>

#include <errno.h>
#include <stdio.h>
#include <fcntl.h>
#include <paths.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>

#include "syslog_private.h"
#include "reentrant.h"
#include "extern.h"

#ifdef __weak_alias
__weak_alias(syslog,_syslog)
__weak_alias(vsyslog,_vsyslog)
__weak_alias(syslogp,_syslogp)
__weak_alias(vsyslogp,_vsyslogp)
__weak_alias(closelog,_closelog)
__weak_alias(openlog,_openlog)
__weak_alias(setlogmask,_setlogmask)
#endif

static struct syslog_data _syslog_data = SYSLOG_DATA_INIT;

#ifdef _REENTRANT
static mutex_t syslog_mutex = MUTEX_INITIALIZER;
#endif

static size_t
timefun(char *p, size_t tbuf_left)
{
struct timeval tv;
time_t now;
struct tm tmnow;
size_t prlen;
char *op = p;

if (gettimeofday(&tv, NULL) == -1)
return snprintf_ss(p, tbuf_left, "-");

/* strftime() implies tzset(), localtime_r() doesn't. */
tzset();
now = (time_t) tv.tv_sec;
localtime_r(&now, &tmnow);

prlen = strftime(p, tbuf_left, "%FT%T", &tmnow);
DEC();
prlen = snprintf(p, tbuf_left, ".%06ld", (long)tv.tv_usec);
DEC();
prlen = strftime(p, tbuf_left-1, "%z", &tmnow);
/* strftime gives eg. "+0200", but we need "+02:00" */
if (prlen == 5) {
p[prlen+1] = p[prlen];
p[prlen] = p[prlen-1];
p[prlen-1] = p[prlen-2];
p[prlen-2] = ':';
prlen += 1;
}
DEC();
return (size_t)(p - op);
}

static int
lock(const struct syslog_data *data)
{
int rv = data == &_syslog_data;
if (rv)
mutex_lock(&syslog_mutex);
return rv;
}

static int
unlock(const struct syslog_data *data)
{
int rv = data == &_syslog_data;
if (rv)
mutex_unlock(&syslog_mutex);
return rv;
}

static struct syslog_fun _syslog_fun = {
timefun,
strerror_r,
vsnprintf,
lock,
unlock,
};

void
openlog(const char *ident, int logstat, int logfac)
{
openlog_r(ident, logstat, logfac, &_syslog_data);
}

void
closelog(void)
{
closelog_r(&_syslog_data);
}

/* setlogmask -- set the log mask level */
int
setlogmask(int pmask)
{
return setlogmask_r(pmask, &_syslog_data);
}

void
openlog_r(const char *ident, int logstat, int logfac, struct syslog_data *data)
{
lock(data);
_openlog_unlocked_r(ident, logstat, logfac, data);
unlock(data);
}

void
closelog_r(struct syslog_data *data)
{
lock(data);
_closelog_unlocked_r(data);
data->log_tag = NULL;
unlock(data);
}

/*
* 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);
_vxsyslogp_r(pri, &_syslog_fun, &_syslog_data, NULL, NULL, fmt, ap);
va_end(ap);
}

void
vsyslog(int pri, const char *fmt, va_list ap)
{
_vxsyslogp_r(pri, &_syslog_fun, &_syslog_data, NULL, NULL, fmt, ap);
}

/*
* syslogp, vsyslogp --
* like syslog but take additional arguments for MSGID and SD
*/
void
syslogp(int pri, const char *msgid, const char *sdfmt, const char *msgfmt, ...)
{
va_list ap;

va_start(ap, msgfmt);
_vxsyslogp_r(pri, &_syslog_fun, &_syslog_data,
msgid, sdfmt, msgfmt, ap);
va_end(ap);
}

void
vsyslogp(int pri, const char *msgid, const char *sdfmt, const char *msgfmt,
va_list ap)
{
_vxsyslogp_r(pri, &_syslog_fun, &_syslog_data,
msgid, sdfmt, msgfmt, ap);
}

void
vsyslogp_r(int pri, struct syslog_data *data, const char *msgid,
const char *sdfmt, const char *msgfmt, va_list ap)
{
_vxsyslogp_r(pri, &_syslog_fun, data, msgid, sdfmt, msgfmt, ap);
}

void
syslog_r(int pri, struct syslog_data *data, const char *fmt, ...)
{
va_list ap;

va_start(ap, fmt);
_vxsyslogp_r(pri, &_syslog_fun, data, NULL, NULL, fmt, ap);
va_end(ap);
}

void
syslogp_r(int pri, struct syslog_data *data, const char *msgid,
const char *sdfmt, const char *msgfmt, ...)
{
va_list ap;

va_start(ap, msgfmt);
_vxsyslogp_r(pri, &_syslog_fun, data, msgid, sdfmt, msgfmt, ap);
va_end(ap);
}

void
vsyslog_r(int pri, struct syslog_data *data, const char *fmt, va_list ap)
{
_vxsyslogp_r(pri, &_syslog_fun, data, NULL, NULL, fmt, ap);
}