usr/src/contrib/news/inn/syslog/syslog.c

/*  $Revision: 1.10 $
**  Modified by Rich $alz <rsalz@osf.org> to be more portable to older
**  systems.
*/
/*#define INET_SYSLOG */
/*
 * Copyright (c) 1983, 1988 Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted provided
 * that: (1) source distributions retain this entire copyright notice and
 * comment, and (2) distributions including binaries display the following
 * acknowledgement:  ``This product includes software developed by the
 * University of California, Berkeley and its contributors'' in the
 * documentation or other materials provided with the distribution and in
 * all advertising materials mentioning features or use of this software.
 * 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 ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)syslog.c    5.28 (Berkeley) 6/27/90";
#endif /* LIBC_SCCS and not lint */

/*
 * SYSLOG -- print message on log file
 *
 * This routine looks a lot like printf, except that it outputs to the
 * log file instead of the standard output.  Also:
 *      adds a timestamp,
 *      prints the module name in front of the message,
 *      has some other formatting types (or will sometime),
 *      adds a newline on the end of the message.
 *
 * The output of this routine is intended to be read by syslogd(8).
 *
 * Author: Eric Allman
 * Modified to use UNIX domain IPC by Ralph Campbell
 */

#include <sys/types.h>
#include <sys/socket.h>
#include <sys/file.h>
#include "syslog.h"
#if     !defined(INET_SYSLOG)
#include <sys/uio.h>
#else
#include <uio.h>
#include <fcntl.h>
#endif  /* !defined(INET_SYSLOG) */
#include <varargs.h>
#include <stdio.h>
#if     defined(INET_SYSLOG)
#include <netinet/in.h>
#endif  /* defined(INET_SYSLOG) */

#ifndef _PATH_LOGNAME
    /* if you are running an old syslog, change /dev/log to the same as it
     * is in syslogd.c */
#define _PATH_LOGNAME   "/dev/log"
#endif
#define index           strchr

#define _PATH_CONSOLE   "/dev/console"

static int      LogFile = -1;           /* fd for log */
static int      connected;              /* have done connect */
static int      LogStat = 0;            /* status bits, set by openlog() */
static char     *LogTag = "syslog";     /* string to tag the entry with */
static int      LogFacility = LOG_USER; /* default facility code */

extern char *index(), *strcpy(), *strncpy(), *strcat();
/* =()<extern @<SIZE_T>@        strlen();>()= */
extern size_t   strlen();

/*
**  Return a string representation of errno.
*/
static char *
xstrerror(e)
    int         e;
{
    extern int  sys_nerr;
    extern char *sys_errlist[];
    static char buff[30];

    if (e >= 0 && e < sys_nerr)
        return sys_errlist[e];
    (void)sprintf(buff, "Error code %d\n", e);
    return buff;
}

/* VARARGS0 */
syslog(va_alist)
    va_dcl
{
        int pri;
        char *fmt;
        va_list ap;

        va_start(ap);
        pri = va_arg(ap, int);
        fmt = va_arg(ap, char*);
        vsyslog(pri, fmt, ap);
        va_end(ap);
}

vsyslog(pri, fmt, ap)
        int pri;
        register char *fmt;
        va_list ap;
{
        extern int errno;
        register int cnt;
        register char *p;
        time_t now, time();
        int fd, saved_errno;
        char tbuf[2048], fmt_cpy[1024], *stdp, *ctime();

        saved_errno = errno;

        /* see if we should just throw out this message */
        if (!LOG_MASK(LOG_PRI(pri)) || (pri &~ (LOG_PRIMASK|LOG_FACMASK)))
                return;
        if (LogFile < 0 || !connected)
                openlog(LogTag, LogStat | LOG_NDELAY, 0);

        /* set default facility if none specified */
        if ((pri & LOG_FACMASK) == 0)
                pri |= LogFacility;

        /* build the message */
        (void)time(&now);
        (void)sprintf(tbuf, "<%d>%.15s ", pri, ctime(&now) + 4);
        for (p = tbuf; *p; ++p);
        if (LogStat & LOG_PERROR)
                stdp = p;
        if (LogTag) {
                (void)strcpy(p, LogTag);
                for (; *p; ++p);
        }
        if (LogStat & LOG_PID) {
                (void)sprintf(p, "[%d]", getpid());
                for (; *p; ++p);
        }
        if (LogTag) {
                *p++ = ':';
                *p++ = ' ';
        }

        /* substitute error message for %m */
        {
                register char ch, *t1, *t2;
                char *xstrerror();

                for (t1 = fmt_cpy; ch = *fmt; ++fmt)
                        if (ch == '%' && fmt[1] == 'm') {
                                ++fmt;
                                for (t2 = xstrerror(saved_errno);
                                    *t1 = *t2++; ++t1);
                        }
                        else
                                *t1++ = ch;
                *t1 = '\0';
        }

        (void)vsprintf(p, fmt_cpy, ap);

        cnt = strlen(tbuf);

        /* output to stderr if requested */
        if (LogStat & LOG_PERROR) {
                struct iovec iov[2];
                register struct iovec *v = iov;

                v->iov_base = stdp;
                v->iov_len = cnt - (stdp - tbuf);
                ++v;
                v->iov_base = "\n";
                v->iov_len = 1;
                (void)writev(2, iov, 2);
        }

        /* output the message to the local logger */
        if (send(LogFile, tbuf, cnt, 0) >= 0 || !(LogStat&LOG_CONS))
                return;

        /*
         * output the message to the console; don't worry about
         * blocking, if console blocks everything will.
         */
        if ((fd = open(_PATH_CONSOLE, O_WRONLY, 0)) < 0)
                return;
        (void)strcat(tbuf, "\r\n");
        cnt += 2;
        p = index(tbuf, '>') + 1;
        (void)write(fd, p, cnt - (p - tbuf));
        (void)close(fd);
}

#if     !defined(INET_SYSLOG)
static struct sockaddr SyslogAddr;      /* AF_UNIX address of local logger */
#else
static struct sockaddr_in SyslogAddr;   /* AF_INET address of local logger */
#endif  /* !defined(INET_SYSLOG) */
/*
 * OPENLOG -- open system log
 */
openlog(ident, logstat, logfac)
        char *ident;
        int logstat, logfac;
{
        if (ident != NULL)
                LogTag = ident;
        LogStat = logstat;
        if (logfac != 0 && (logfac &~ LOG_FACMASK) == 0)
                LogFacility = logfac;
        if (LogFile == -1) {
#if     !defined(INET_SYSLOG)
                SyslogAddr.sa_family = AF_UNIX;
                strncpy(SyslogAddr.sa_data, _PATH_LOGNAME,
                    sizeof(SyslogAddr.sa_data));
                if (LogStat & LOG_NDELAY) {
                        LogFile = socket(AF_UNIX, SOCK_DGRAM, 0);
                        fcntl(LogFile, F_SETFD, 1);
                }
#else
                SyslogAddr.sin_family = AF_INET;
                SyslogAddr.sin_port = htons(514);
                SyslogAddr.sin_addr.s_addr = INADDR_ANY;
                if (LogStat & LOG_NDELAY) {
                        LogFile = socket(AF_INET, SOCK_DGRAM, 0);
                        fcntl(LogFile, F_SETFD, 1);
                }
#endif  /* !defined(INET_SYSLOG) */
        }
        if (LogFile != -1 && !connected &&
            connect(LogFile, &SyslogAddr, sizeof(SyslogAddr)) != -1)
                connected = 1;
}

/*
 * CLOSELOG -- close the system log
 */
closelog()
{
        (void) close(LogFile);
        LogFile = -1;
        connected = 0;
}

static int      LogMask = 0xff;         /* mask of priorities to be logged */
/*
 * SETLOGMASK -- set the log mask level
 */
setlogmask(pmask)
        int pmask;
{
        int omask;

        omask = LogMask;
        if (pmask != 0)
                LogMask = pmask;
        return (omask);
}