/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2012 The FreeBSD Foundation
 *
 * This software was developed by Edward Tomasz Napierala under sponsorship
 * from the FreeBSD Foundation.
 *
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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>
#include <errno.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <vis.h>

#include "common.h"

static int log_level = 0;
static char *peer_name = NULL;
static char *peer_addr = NULL;

#define MSGBUF_LEN      1024

void
log_init(int level)
{

        log_level = level;
        openlog(getprogname(), LOG_NDELAY | LOG_PID, LOG_DAEMON);
}

void
log_set_peer_name(const char *name)
{

        /*
         * XXX: Turn it into assertion?
         */
        if (peer_name != NULL)
                log_errx(1, "%s called twice", __func__);
        if (peer_addr == NULL)
                log_errx(1, "%s called before log_set_peer_addr", __func__);

        peer_name = checked_strdup(name);
}

void
log_set_peer_addr(const char *addr)
{

        /*
         * XXX: Turn it into assertion?
         */
        if (peer_addr != NULL)
                log_errx(1, "%s called twice", __func__);

        peer_addr = checked_strdup(addr);
}

static void
log_common(int priority, int log_errno, const char *fmt, va_list ap)
{
        static char msgbuf[MSGBUF_LEN];
        static char msgbuf_strvised[MSGBUF_LEN * 4 + 1];
        char *errstr;
        int ret;

        ret = vsnprintf(msgbuf, sizeof(msgbuf), fmt, ap);
        if (ret < 0) {
                fprintf(stderr, "%s: snprintf failed", getprogname());
                syslog(LOG_CRIT, "snprintf failed");
                exit(1);
        }

        ret = strnvis(msgbuf_strvised, sizeof(msgbuf_strvised), msgbuf, VIS_NL);
        if (ret < 0) {
                fprintf(stderr, "%s: strnvis failed", getprogname());
                syslog(LOG_CRIT, "strnvis failed");
                exit(1);
        }

        if (log_errno == -1) {
                if (peer_name != NULL) {
                        fprintf(stderr, "%s: %s (%s): %s\n", getprogname(),
                            peer_addr, peer_name, msgbuf_strvised);
                        syslog(priority, "%s (%s): %s",
                            peer_addr, peer_name, msgbuf_strvised);
                } else if (peer_addr != NULL) {
                        fprintf(stderr, "%s: %s: %s\n", getprogname(),
                            peer_addr, msgbuf_strvised);
                        syslog(priority, "%s: %s",
                            peer_addr, msgbuf_strvised);
                } else {
                        fprintf(stderr, "%s: %s\n", getprogname(), msgbuf_strvised);
                        syslog(priority, "%s", msgbuf_strvised);
                }

        } else {
                errstr = strerror(log_errno);

                if (peer_name != NULL) {
                        fprintf(stderr, "%s: %s (%s): %s: %s\n", getprogname(),
                            peer_addr, peer_name, msgbuf_strvised, errstr);
                        syslog(priority, "%s (%s): %s: %s",
                            peer_addr, peer_name, msgbuf_strvised, errstr);
                } else if (peer_addr != NULL) {
                        fprintf(stderr, "%s: %s: %s: %s\n", getprogname(),
                            peer_addr, msgbuf_strvised, errstr);
                        syslog(priority, "%s: %s: %s",
                            peer_addr, msgbuf_strvised, errstr);
                } else {
                        fprintf(stderr, "%s: %s: %s\n", getprogname(),
                            msgbuf_strvised, errstr);
                        syslog(priority, "%s: %s",
                            msgbuf_strvised, errstr);
                }
        }
}

void
log_err(int eval, const char *fmt, ...)
{
        va_list ap;

        va_start(ap, fmt);
        log_common(LOG_CRIT, errno, fmt, ap);
        va_end(ap);

        exit(eval);
}

void
log_errx(int eval, const char *fmt, ...)
{
        va_list ap;

        va_start(ap, fmt);
        log_common(LOG_CRIT, -1, fmt, ap);
        va_end(ap);

        exit(eval);
}

void
log_warn(const char *fmt, ...)
{
        va_list ap;

        va_start(ap, fmt);
        log_common(LOG_WARNING, errno, fmt, ap);
        va_end(ap);
}

void
log_warnx(const char *fmt, ...)
{
        va_list ap;

        va_start(ap, fmt);
        log_common(LOG_WARNING, -1, fmt, ap);
        va_end(ap);
}

void
log_debugx(const char *fmt, ...)
{
        va_list ap;

        if (log_level == 0)
                return;

        va_start(ap, fmt);
        log_common(LOG_DEBUG, -1, fmt, ap);
        va_end(ap);
}