busybox/sysklogd/logger.c

/* vi: set sw=4 ts=4: */
/*
 * Mini logger implementation for busybox
 *
 * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
 *
 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
 */
//config:config LOGGER
//config:	bool "logger (6.3 kb)"
//config:	default y
//config:	select FEATURE_SYSLOG
//config:	help
//config:	The logger utility allows you to send arbitrary text
//config:	messages to the system log (i.e. the 'syslogd' utility) so
//config:	they can be logged. This is generally used to help locate
//config:	problems that occur within programs and scripts.

//applet:IF_LOGGER(APPLET(logger, BB_DIR_USR_BIN, BB_SUID_DROP))

//kbuild:lib-$(CONFIG_LOGGER) += syslogd_and_logger.o

//usage:#define logger_trivial_usage
//usage:       "[-s] [-t TAG] [-p PRIO] [MESSAGE]"
//usage:#define logger_full_usage "\n\n"
//usage:       "Write MESSAGE (or stdin) to syslog\n"
//usage:     "\n	-s	Log to stderr as well as the system log"
//usage:     "\n	-t TAG	Log using the specified tag (defaults to user name)"
//usage:     "\n	-p PRIO	Priority (number or FACILITY.LEVEL pair)"
//usage:
//usage:#define logger_example_usage
//usage:       "$ logger \"hello\"\n"

/*
 * Done in syslogd_and_logger.c:
#include "libbb.h"
#define SYSLOG_NAMES
#define SYSLOG_NAMES_CONST
#include <syslog.h>
*/

/* Decode a symbolic name to a numeric value
 * this function is based on code
 * Copyright (c) 1983, 1993
 * The Regents of the University of California.  All rights reserved.
 *
 * Original copyright notice is retained at the end of this file.
 */
static int decode(char *name, const CODE *codetab)
{
	const CODE *c;

	if (isdigit(*name))
		return atoi(name);
	for (c = codetab; c->c_name; c++) {
		if (!strcasecmp(name, c->c_name)) {
			return c->c_val;
		}
	}

	return -1;
}

/* Decode a symbolic name to a numeric value
 * this function is based on code
 * Copyright (c) 1983, 1993
 * The Regents of the University of California.  All rights reserved.
 *
 * Original copyright notice is retained at the end of this file.
 */
static int pencode(char *s)
{
	char *save;
	int lev, fac = LOG_USER;

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

#define strbuf bb_common_bufsiz1

int logger_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int logger_main(int argc UNUSED_PARAM, char **argv)
{
	char *str_p, *str_t;
	int opt;
	int i = 0;

	setup_common_bufsiz();

	/* Fill out the name string early (may be overwritten later) */
	str_t = uid2uname_utoa(geteuid());

	/* Parse any options */
	opt = getopt32(argv, "p:st:", &str_p, &str_t);

	if (opt & 0x2) /* -s */
		i |= LOG_PERROR;
	//if (opt & 0x4) /* -t */
	openlog(str_t, i, 0);
	i = LOG_USER | LOG_NOTICE;
	if (opt & 0x1) /* -p */
		i = pencode(str_p);

	argv += optind;
	if (!argv[0]) {
		while (fgets(strbuf, COMMON_BUFSIZE, stdin)) {
			if (strbuf[0]
			 && NOT_LONE_CHAR(strbuf, '\n')
			) {
				/* Neither "" nor "\n" */
				syslog(i, "%s", strbuf);
			}
		}
	} else {
		char *message = NULL;
		int len = 0;
		int pos = 0;
		do {
			len += strlen(*argv) + 1;
			message = xrealloc(message, len + 1);
			sprintf(message + pos, " %s", *argv),
			pos = len;
		} while (*++argv);
		syslog(i, "%s", message + 1); /* skip leading " " */
	}

	closelog();
	return EXIT_SUCCESS;
}

/* Clean up. Needed because we are included from syslogd_and_logger.c */
#undef strbuf

/*-
 * Copyright (c) 1983, 1993
 * The Regents of the University of California.  All rights reserved.
 *
 * This is the original license statement for the decode and pencode functions.
 *
 * 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. BSD Advertising Clause omitted per the July 22, 1999 licensing change
 *    ftp://ftp.cs.berkeley.edu/pub/4bsd/README.Impt.License.Change
 *
 * 4. 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.
 */