/*      $OpenBSD: log.c,v 1.1 2008/06/26 15:10:01 pyr 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 MIND, 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 <sys/types.h>

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

void             log_init(int);
void             log_warn(const char *, ...);
void             log_warnx(const char *, ...);
void             log_info(const char *, ...);
void             log_debug(const char *, ...);
__dead2 void     fatal(const char *);
__dead2 void     fatalx(const char *);

int      debug;

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

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

        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
vlog(int pri, const char *fmt, va_list ap)
{
        char    *nfmt;

        if (debug) {
                /* best effort in out of mem situations */
                if (asprintf(&nfmt, "%s\n", fmt) == -1) {
                        vfprintf(stderr, fmt, ap);
                        fprintf(stderr, "\n");
                } else {
                        vfprintf(stderr, nfmt, ap);
                        free(nfmt);
                }
                fflush(stderr);
        } else
                vsyslog(pri, fmt, ap);
}


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

        /* best effort to even work in out of memory situations */
        if (emsg == NULL)
                logit(LOG_CRIT, "%s", strerror(errno));
        else {
                va_start(ap, emsg);

                if (asprintf(&nfmt, "%s: %s", emsg, strerror(errno)) == -1) {
                        /* we tried it... */
                        vlog(LOG_CRIT, emsg, ap);
                        logit(LOG_CRIT, "%s", strerror(errno));
                } else {
                        vlog(LOG_CRIT, nfmt, ap);
                        free(nfmt);
                }
                va_end(ap);
        }
}

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

        va_start(ap, emsg);
        vlog(LOG_CRIT, 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;

        if (debug > 1) {
                va_start(ap, emsg);
                vlog(LOG_DEBUG, emsg, ap);
                va_end(ap);
        }
}

void
fatal(const char *emsg)
{
        if (emsg == NULL)
                logit(LOG_CRIT, "fatal: %s", strerror(errno));
        else
                if (errno)
                        logit(LOG_CRIT, "fatal: %s: %s",
                            emsg, strerror(errno));
                else
                        logit(LOG_CRIT, "fatal: %s", emsg);

        exit(1);
}

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