gen.subproj/syslog.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /*
  23  * Copyright (c) 1993
  24  *      The Regents of the University of California.  All rights reserved.
  25  *
  26  * Redistribution and use in source and binary forms, with or without
  27  * modification, are permitted provided that the following conditions
  28  * are met:
  29  * 1. Redistributions of source code must retain the above copyright
  30  *    notice, this list of conditions and the following disclaimer.
  31  * 2. Redistributions in binary form must reproduce the above copyright
  32  *    notice, this list of conditions and the following disclaimer in the
  33  *    documentation and/or other materials provided with the distribution.
  34  * 3. All advertising materials mentioning features or use of this software
  35  *    must display the following acknowledgement:
  36  *      This product includes software developed by the University of
  37  *      California, Berkeley and its contributors.
  38  * 4. Neither the name of the University nor the names of its contributors
  39  *    may be used to endorse or promote products derived from this software
  40  *    without specific prior written permission.
  41  *
  42  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  43  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  44  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  45  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  46  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  47  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  48  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  49  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  50  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  51  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  52  * SUCH DAMAGE.
  53  */
  54
  55 #include <sys/types.h>
  56 #include <sys/socket.h>
  57 #include <sys/syslog.h>
  58 #include <sys/uio.h>
  59 #include <sys/un.h>
  60 #include <netdb.h>
  61
  62 #include <errno.h>
  63 #include <fcntl.h>
  64 #include <paths.h>
  65 #include <stdio.h>
  66 #include <string.h>
  67 #include <time.h>
  68 #include <unistd.h>
  69
  70 #ifdef __STDC__
  71 #include <stdarg.h>
  72 #else
  73 #include <varargs.h>
  74 #endif
  75
  76 #include <crt_externs.h>
  77
  78 static int      LogFile = -1;           /* fd for log */
  79 static int      connected;              /* have done connect */
  80 static int      LogStat = 0;            /* status bits, set by openlog() */
  81 static const char *LogTag = NULL;       /* string to tag the entry with */
  82 static int      LogFacility = LOG_USER; /* default facility code */
  83 static int      LogMask = 0xff;         /* mask of priorities to be logged */
  84
  85 /*
  86  * syslog, vsyslog --
  87  *      print message on log file; output is intended for syslogd(8).
  88  */
  89 void
  90 #ifdef __STDC__
  91 syslog(int pri, const char *fmt, ...)
  92 #else
  93 syslog(pri, fmt, va_alist)
  94         int pri;
  95         char *fmt;
  96         va_dcl
  97 #endif
  98 {
  99         va_list ap;
 100
 101 #ifdef __STDC__
 102         va_start(ap, fmt);
 103 #else
 104         va_start(ap);
 105 #endif
 106         vsyslog(pri, fmt, ap);
 107         va_end(ap);
 108 }
 109
 110 void
 111 vsyslog(pri, fmt, ap)
 112         int pri;
 113         register const char *fmt;
 114         va_list ap;
 115 {
 116         register int cnt;
 117         register char ch, *p, *t;
 118         time_t now;
 119         int fd, saved_errno;
 120 #define TBUF_LEN        2048
 121 #define FMT_LEN         1024
 122         char *stdp, tbuf[TBUF_LEN], fmt_cpy[FMT_LEN];
 123         int tbuf_left, fmt_left, prlen;
 124
 125 #define INTERNALLOG     LOG_ERR|LOG_CONS|LOG_PERROR|LOG_PID
 126         /* Check for invalid bits. */
 127         if (pri & ~(LOG_PRIMASK|LOG_FACMASK)) {
 128                 syslog(INTERNALLOG,
 129                     "syslog: unknown facility/priority: %x", pri);
 130                 pri &= LOG_PRIMASK|LOG_FACMASK;
 131         }
 132
 133         /* Check priority against setlogmask values. */
 134         if (!(LOG_MASK(LOG_PRI(pri)) & LogMask))
 135                 return;
 136
 137         saved_errno = errno;
 138
 139         /* Set default facility if none specified. */
 140         if ((pri & LOG_FACMASK) == 0)
 141                 pri |= LogFacility;
 142
 143         /* Build the message. */
 144
 145         /*
 146          * Although it's tempting, we can't ignore the possibility of
 147          * overflowing the buffer when assembling the "fixed" portion
 148          * of the message.  Strftime's "%h" directive expands to the
 149          * locale's abbreviated month name, but if the user has the
 150          * ability to construct to his own locale files, it may be
 151          * arbitrarily long.
 152          */
 153         (void)time(&now);
 154
 155         p = tbuf;
 156         tbuf_left = TBUF_LEN;
 157
 158 #define DEC()   \
 159         do {                                    \
 160                 if (prlen >= tbuf_left)         \
 161                         prlen = tbuf_left - 1;  \
 162                 p += prlen;                     \
 163                 tbuf_left -= prlen;             \
 164         } while (0)
 165
 166         prlen = snprintf(p, tbuf_left, "<%d>", pri);
 167         DEC();
 168
 169         prlen = strftime(p, tbuf_left, "%h %e %T ", localtime(&now));
 170         DEC();
 171
 172         if (LogStat & LOG_PERROR)
 173                 stdp = p;
 174         if (LogTag == NULL)
 175                 LogTag = *(*_NSGetArgv());
 176         if (LogTag != NULL) {
 177                 prlen = snprintf(p, tbuf_left, "%s", LogTag);
 178                 DEC();
 179         }
 180         if (LogStat & LOG_PID) {
 181                 prlen = snprintf(p, tbuf_left, "[%d]", getpid());
 182                 DEC();
 183         }
 184         if (LogTag != NULL) {
 185                 if (tbuf_left > 1) {
 186                         *p++ = ':';
 187                         tbuf_left--;
 188                 }
 189                 if (tbuf_left > 1) {
 190                         *p++ = ' ';
 191                         tbuf_left--;
 192                 }
 193         }
 194
 195         /*
 196          * We wouldn't need this mess if printf handled %m, or if
 197          * strerror() had been invented before syslog().
 198          */
 199         for (t = fmt_cpy, fmt_left = FMT_LEN; (ch = *fmt); ++fmt) {
 200                 if (ch == '%' && fmt[1] == 'm') {
 201                         ++fmt;
 202                         prlen = snprintf(t, fmt_left, "%s",
 203                             strerror(saved_errno));
 204                         if (prlen >= fmt_left)
 205                                 prlen = fmt_left - 1;
 206                         t += prlen;
 207                         fmt_left -= prlen;
 208                 } else {
 209                         if (fmt_left > 1) {
 210                                 *t++ = ch;
 211                                 fmt_left--;
 212                         }
 213                 }
 214         }
 215         *t = '\0';
 216
 217         prlen = vsnprintf(p, tbuf_left, fmt_cpy, ap);
 218         DEC();
 219         cnt = p - tbuf;
 220
 221         /* Output to stderr if requested. */
 222         if (LogStat & LOG_PERROR) {
 223                 struct iovec iov[2];
 224
 225                 iov[0].iov_base = stdp;
 226                 iov[0].iov_len = cnt - (stdp - tbuf);
 227                 iov[1].iov_base = "\n";
 228                 iov[1].iov_len = 1;
 229                 (void)writev(STDERR_FILENO, iov, 2);
 230         }
 231
 232         /* Get connected, output the message to the local logger. */
 233         if (!connected)
 234                 openlog(LogTag, LogStat | LOG_NDELAY, 0);
 235         if (send(LogFile, tbuf, cnt, 0) >= 0)
 236                 return;
 237
 238         /*
 239          * Output the message to the console; don't worry about blocking,
 240          * if console blocks everything will.  Make sure the error reported
 241          * is the one from the syslogd failure.
 242          */
 243         if (LogStat & LOG_CONS &&
 244             (fd = open(_PATH_CONSOLE, O_WRONLY, 0)) >= 0) {
 245                 struct iovec iov[2];
 246
 247                 p = strchr(tbuf, '>') + 1;
 248                 iov[0].iov_base = p;
 249                 iov[0].iov_len = cnt - (p - tbuf);
 250                 iov[1].iov_base = "\r\n";
 251                 iov[1].iov_len = 2;
 252                 (void)writev(fd, iov, 2);
 253                 (void)close(fd);
 254         }
 255 }
 256
 257 static struct sockaddr_un SyslogAddr;   /* AF_UNIX address of local logger */
 258
 259 void
 260 openlog(ident, logstat, logfac)
 261         const char *ident;
 262         int logstat, logfac;
 263 {
 264         if (ident != NULL)
 265                 LogTag = ident;
 266         LogStat = logstat;
 267         if (logfac != 0 && (logfac &~ LOG_FACMASK) == 0)
 268                 LogFacility = logfac;
 269
 270         if (LogFile == -1) {
 271                 SyslogAddr.sun_family = AF_UNIX;
 272                 (void)strncpy(SyslogAddr.sun_path, _PATH_LOG,
 273                     sizeof(SyslogAddr.sun_path));
 274                 if (LogStat & LOG_NDELAY) {
 275                         if ((LogFile = socket(AF_UNIX, SOCK_DGRAM, 0)) == -1)
 276                                 return;
 277                         (void)fcntl(LogFile, F_SETFD, 1);
 278                 }
 279         }
 280         if (LogFile != -1 && !connected)
 281                 if (connect(LogFile, &SyslogAddr, sizeof(SyslogAddr)) == -1) {
 282                         (void)close(LogFile);
 283                         LogFile = -1;
 284                 } else
 285                         connected = 1;
 286 }
 287
 288 void
 289 closelog()
 290 {
 291         (void)close(LogFile);
 292         LogFile = -1;
 293         connected = 0;
 294 }
 295
 296 /* setlogmask -- set the log mask level */
 297 int
 298 setlogmask(pmask)
 299         int pmask;
 300 {
 301         int omask;
 302
 303         omask = LogMask;
 304         if (pmask != 0)
 305                 LogMask = pmask;
 306         return (omask);
 307 }