/*	$OpenBSD: logger.c,v 1.17 2016/03/28 18:18:52 chl Exp $	*/
/*	$NetBSD: logger.c,v 1.4 1994/12/22 06:27:00 jtc 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.
 */

#define _DEFAULT_SOURCE

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

#define SYSLOG_NAMES
#include <syslog.h>

int decode(char *, CODE *);
int pencode(char *);
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;
  char *tag, buf[1024];

  tag = NULL;
  pri = LOG_NOTICE;
  logflags = 0;
  while ((ch = getopt(argc, argv, "f:ip:st:")) != -1)
    switch (ch) {
    case 'f': /* file to log */
      if (freopen(optarg, "r", stdin) == NULL) {
        (void)fprintf(stderr, "logger: %s: %s.\n", optarg, strerror(errno));
        exit(1);
      }
      break;
    case 'i': /* log process id also */
      logflags |= LOG_PID;
      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 ? 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;) {
      len = strlen(*argv);
      if (p + len > endp && p > buf) {
        syslog(pri, "%s", buf);
        p = buf;
      }
      if (len > sizeof(buf) - 1)
        syslog(pri, "%s", *argv++);
      else {
        if (p != buf)
          *p++ = ' ';
        bcopy(*argv++, p, len);
        *(p += len) = '\0';
      }
    }
    if (p != buf)
      syslog(pri, "%s", buf);
  } else
    while (fgets(buf, sizeof(buf), stdin) != NULL)
      syslog(pri, "%s", buf);
  exit(0);
}

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

  for (save = s; *s && *s != '.'; ++s)
    ;
  if (*s) {
    *s = '\0';
    fac = decode(save, facilitynames);
    if (fac < 0) {
      (void)fprintf(stderr, "logger: unknown facility name: %s.\n", save);
      exit(1);
    }
    *s++ = '.';
  } else {
    fac = 0;
    s = save;
  }
  lev = decode(s, prioritynames);
  if (lev < 0) {
    (void)fprintf(stderr, "logger: unknown priority name: %s.\n", save);
    exit(1);
  }
  return ((lev & LOG_PRIMASK) | (fac & LOG_FACMASK));
}

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

  if (isdigit((unsigned char)*name)) {
    int n = (int)strtol(name, NULL, 10);
    return (n);
  }

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

  return (-1);
}

void usage(void) {
  (void)fprintf(
      stderr,
      "usage: logger [-is] [-f file] [-p pri] [-t tag] [message ...]\n");
  exit(1);
}
