/*      $OpenBSD: log.c,v 1.64 2017/03/21 12:06:55 bluhm 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 <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <syslog.h>
#include <errno.h>
#include <time.h>

#include "log.h"

static int               debug;
static int               verbose;
static const char       *log_procname;

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

        debug = n_debug;
        verbose = n_debug;
        log_procinit(__progname);

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

        tzset();
}

void
log_procinit(const char *procname)
{
        if (procname != NULL)
                log_procname = procname;
}

void
log_setverbose(int v)
{
        verbose = v;
}

int
log_getverbose(void)
{
        return (verbose);
}

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;
        int      saved_errno = errno;

        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);

        errno = saved_errno;
}

void
log_warn(const char *emsg, ...)
{
        char            *nfmt;
        va_list          ap;
        int              saved_errno = errno;

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

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

        errno = saved_errno;
}

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;

        if (verbose) {
                va_start(ap, emsg);
                vlog(LOG_DEBUG, emsg, ap);
                va_end(ap);
        }
}

static void
vfatalc(int code, const char *emsg, va_list ap)
{
        static char     s[BUFSIZ];
        const char      *sep;

        if (emsg != NULL) {
                (void)vsnprintf(s, sizeof(s), emsg, ap);
                sep = ": ";
        } else {
                s[0] = '\0';
                sep = "";
        }
        if (code)
                logit(LOG_CRIT, "fatal in %s: %s%s%s",
                    log_procname, s, sep, strerror(code));
        else
                logit(LOG_CRIT, "fatal in %s%s%s", log_procname, sep, s);
}

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

        va_start(ap, emsg);
        vfatalc(errno, emsg, ap);
        va_end(ap);
        exit(1);
}

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

        va_start(ap, emsg);
        vfatalc(0, emsg, ap);
        va_end(ap);
        exit(1);
}