put %m back in

[unix-history] / usr / src / lib / libc / gen / syslog.c

/*
* 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 the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by the University of California, Berkeley.  The name of the
* University may not 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 MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/

#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)syslog.c    5.19 (Berkeley) %G%";
#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 <sys/signal.h>
#include <sys/syslog.h>
#include <netdb.h>
#include <strings.h>
#include <varargs.h>
#include <stdio.h>

#define LOGNAME "/dev/log"
#define 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 */

syslog(pri, fmt, args)
       int pri, args;
       char *fmt;
{
       vsyslog(pri, fmt, &args);
}

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 pid, saved_errno;
       char tbuf[2048], fmt_cpy[1024], *ctime();

       saved_errno = errno;

       /* see if we should just throw out this message */
       if ((u_int)LOG_FAC(pri) >= LOG_NFACILITIES ||
           !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 (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 *strerror();

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

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

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

       /* output the message to the console */
       pid = vfork();
       if (pid == -1)
               return;
       if (pid == 0) {
               int fd;
               long sigsetmask();

               (void)signal(SIGALRM, SIG_DFL);
               sigsetmask((long)~sigmask(SIGALRM));
               (void)alarm((u_int)5);
               if ((fd = open(CONSOLE, O_WRONLY, 0)) < 0)
                       return;
               (void)alarm((u_int)0);
               (void)strcat(tbuf, "\r");
               p = index(tbuf, '>') + 1;
               (void)write(fd, p, cnt + 1 - (p - tbuf));
               (void)close(fd);
               _exit(0);
       }
       if (!(LogStat & LOG_NOWAIT))
               while ((cnt = wait((int *)0)) > 0 && cnt != pid);
}

static struct sockaddr SyslogAddr;      /* AF_UNIX address of local logger */
/*
* 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) {
               SyslogAddr.sa_family = AF_UNIX;
               strncpy(SyslogAddr.sa_data, LOGNAME, sizeof SyslogAddr.sa_data);
               if (LogStat & LOG_NDELAY) {
                       LogFile = socket(AF_UNIX, SOCK_DGRAM, 0);
                       fcntl(LogFile, F_SETFD, 1);
               }
       }
       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);
}