/*      $NetBSD: logger.c,v 1.17 2012/04/27 06:30:48 wiz Exp $  */

/*
 * Copyright (c) 1983, 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>
#ifndef lint
__COPYRIGHT("@(#) Copyright (c) 1983, 1993\
 The Regents of the University of California.  All rights reserved.");
#endif /* not lint */

#ifndef lint
#if 0
static char sccsid[] = "@(#)logger.c    8.1 (Berkeley) 6/6/93";
#endif
__RCSID("$NetBSD: logger.c,v 1.17 2012/04/27 06:30:48 wiz Exp $");
#endif /* not lint */

#include <errno.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <ctype.h>
#include <string.h>
#include <err.h>

#define SYSLOG_NAMES
#include <syslog.h>

static int      decode(const char *, const CODE *);
static int      pencode(char *);
__dead static void      usage(void);

/*
 * logger -- read and log utility
 *
 *      Reads from an input and arranges to write the result on the system
 *      log.
 */
int
main(int argc, char *argv[])
{
        int ch, logflags, pri;
        const char *tag;
        const char *sd = "-";
        const char *msgid = "-";
        char buf[1024];

        tag = NULL;
        pri = LOG_NOTICE;
        logflags = 0;
        while ((ch = getopt(argc, argv, "cd:f:im:np:st:")) != -1)
                switch((char)ch) {
                case 'c':       /* log to console */
                        logflags |= LOG_CONS;
                        break;
                case 'd':               /* structured data field */
                        sd = optarg;
                        break;
                case 'f':               /* file to log */
                        if (freopen(optarg, "r", stdin) == NULL)
                                err(EXIT_FAILURE, "%s", optarg);
                        break;
                case 'i':               /* log process id also */
                        logflags |= LOG_PID;
                        break;
                case 'm':               /* msgid field */
                        msgid = optarg;
                        break;
                case 'n':               /* open log file immediately */
                        logflags |= LOG_NDELAY;
                        break;
                case 'p':               /* priority */
                        pri = pencode(optarg);
                        break;
                case 's':               /* log to standard error */
                        logflags |= LOG_PERROR;
                        break;
                case 't':               /* tag */
                        tag = optarg;
                        break;
                case '?':
                default:
                        usage();
                }
        argc -= optind;
        argv += optind;

        /* setup for logging */
        openlog(tag != NULL ? tag : getlogin(), logflags, 0);
        (void)fclose(stdout);

        /* log input line if appropriate */
        if (argc > 0) {
                char *p, *endp;
                size_t len;

                for (p = buf, endp = buf + sizeof(buf) - 2; *argv != NULL;) {
                        len = strlen(*argv);
                        if (p + len > endp && p > buf) {
                                syslogp(pri, msgid, sd, "%s", buf);
                                p = buf;
                        }
                        if (len > sizeof(buf) - 1)
                                syslogp(pri, msgid, sd, "%s", *argv++);
                        else {
                                if (p != buf)
                                        *p++ = ' ';
                                memmove(p, *argv++, len);
                                *(p += len) = '\0';
                        }
                }
                if (p != buf)
                        syslogp(pri, msgid, sd, "%s", buf);
        } else  /* TODO: allow syslog-protocol messages from file/stdin
                 *       but that will require parsing the line to split
                 *       it into three fields.
                 */
                while (fgets(buf, sizeof(buf), stdin) != NULL)
                        syslogp(pri, msgid, sd, "%s", buf);

        exit(EXIT_SUCCESS);
        /* NOTREACHED */
}

/*
 *  Decode a symbolic name to a numeric value
 */
static int
pencode(char *s)
{
        char *save;
        int fac, lev;

        for (save = s; *s != '\0' && *s != '.'; ++s)
                ;
        if (*s != '\0') {
                *s = '\0';
                fac = decode(save, facilitynames);
                if (fac < 0)
                        errx(EXIT_FAILURE, "unknown facility name: %s", save);
                *s++ = '.';
        } else {
                fac = 0;
                s = save;
        }
        lev = decode(s, prioritynames);
        if (lev < 0)
                errx(EXIT_FAILURE, "unknown priority name: %s", s);
        return ((lev & LOG_PRIMASK) | (fac & LOG_FACMASK));
}

static int
decode(const char *name, const CODE *codetab)
{
        const CODE *c;

        if (isdigit((unsigned char)*name))
                return (atoi(name));

        for (c = codetab; c->c_name != NULL; c++)
                if (strcasecmp(name, c->c_name) == 0)
                        return (c->c_val);

        return (-1);
}

static void
usage(void)
{

        (void)fprintf(stderr,
            "Usage: %s [-cins] [-d SD] [-f file] [-m msgid] "
            "[-p pri] [-t tag] [message ...]\n",
            getprogname());
        exit(EXIT_FAILURE);
}