/*      $OpenBSD: log.c,v 1.4 2017/07/28 13:05:21 florian Exp $ */

/*
 * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <err.h>
#include <errno.h>
#include <netdb.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <time.h>
#include <unistd.h>

#include "log.h"

static int debug;

static char     *logqueue;

#define LOGQUEUE_SIZE 1024

void    logit(int, const char *, ...);
void    vlog(int pri, const char *fmt, va_list ap);

void
log_init(int n_debug)
{
        extern char     *__progname;

        if (logqueue == NULL) {
                logqueue = calloc(LOGQUEUE_SIZE, 1);
                if (logqueue == NULL)
                        err(1, NULL);
        }

        debug = n_debug;

        if (!debug)
                openlog(__progname, LOG_PID | LOG_NDELAY, LOG_DAEMON);

        tzset();
}

void
logit(int pri, const char *fmt, ...)
{
        va_list ap;

        va_start(ap, fmt);
        vlog(pri, fmt, ap);
        va_end(ap);
}

void
log_enqueue(const char *fmt, ...)
{
        char tmpbuf[LOGQUEUE_SIZE];
        va_list ap;

        va_start(ap, fmt);
        (void)vsnprintf(tmpbuf, sizeof(tmpbuf), fmt, ap);
        va_end(ap);
        (void)strlcat(logqueue, tmpbuf, LOGQUEUE_SIZE);
}


void
vlog(int pri, const char *fmt, va_list ap)
{
        char    tmpbuf[1024];
        char    logbuf[LOGQUEUE_SIZE + sizeof(tmpbuf)];

        if (pri == LOG_DEBUG && !debug) {
                logqueue[0] = '\0';
                return;
        }

        (void)vsnprintf(tmpbuf, sizeof(tmpbuf), fmt, ap);
        (void)strlcpy(logbuf, logqueue, sizeof(logbuf));
        (void)strlcat(logbuf, tmpbuf, sizeof(logbuf));

        logqueue[0] = '\0';

        if (debug) {
                fprintf(stderr, "%s\n", logbuf);
                fflush(stderr);
        } else
                syslog(pri, "%s", logbuf);
}

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

        if (emsg == NULL)
                logit(LOG_ERR, "%s", strerror(errno));
        else {
                va_start(ap, emsg);

                /* best effort to even work in out of memory situations */
                if (asprintf(&nfmt, "%s: %s", emsg, strerror(errno)) == -1) {
                        /* we tried it... */
                        vlog(LOG_ERR, emsg, ap);
                        logit(LOG_ERR, "%s", strerror(errno));
                } else {
                        vlog(LOG_ERR, nfmt, ap);
                        free(nfmt);
                }
                va_end(ap);
        }
}

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

        va_start(ap, emsg);
        vlog(LOG_ERR, emsg, ap);
        va_end(ap);
}

void
log_info(const char *emsg, ...)
{
        va_list  ap;

        va_start(ap, emsg);
        vlog(LOG_INFO, emsg, ap);
        va_end(ap);
}

void
log_debug(const char *emsg, ...)
{
        va_list  ap;

        va_start(ap, emsg);
        vlog(LOG_DEBUG, emsg, ap);
        va_end(ap);
}

void
fatal(const char *emsg)
{
        extern char     *__progname;
        extern __dead void rtdexit(void);

        if (emsg == NULL)
                logit(LOG_CRIT, "fatal in %s: %s", __progname,
                    strerror(errno));
        else
                if (errno)
                        logit(LOG_CRIT, "fatal in %s: %s: %s",
                            __progname, emsg, strerror(errno));
                else
                        logit(LOG_CRIT, "fatal in %s: %s",
                            __progname, emsg);

        rtdexit();
}

void
fatalx(const char *emsg)
{
        errno = 0;
        fatal(emsg);
}