src/log.c

   1 /* -*- mode: c; c-file-style: "openbsd" -*- */
   2 /*      $OpenBSD: log.c,v 1.11 2007/12/07 17:17:00 reyk Exp $   */
   3
   4 /*
   5  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
   6  *
   7  * Permission to use, copy, modify, and/or distribute this software for any
   8  * purpose with or without fee is hereby granted, provided that the above
   9  * copyright notice and this permission notice appear in all copies.
  10  *
  11  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  13  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  15  * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
  16  * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
  17  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  18  */
  19
  20 #define _GNU_SOURCE
  21 #include <unistd.h>
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <stdarg.h>
  25 #include <syslog.h>
  26 #include <sys/types.h>
  27 #include <string.h>
  28 #include <errno.h>
  29 #include <time.h>
  30
  31 /* By default, logging is done on stderr. */
  32 static int       debug = 1;
  33
  34 /* Logging can be modified by providing an appropriate log handler. */
  35 static void (*logh)(int severity, const char *msg) = NULL;
  36
  37 static void      vlog(int, const char *, va_list);
  38 static void      logit(int, const char *, ...);
  39
  40 void
  41 log_init(int n_debug, const char *progname)
  42 {
  43         debug = n_debug;
  44
  45         if (!debug)
  46                 openlog(progname, LOG_PID | LOG_NDELAY, LOG_DAEMON);
  47
  48         tzset();
  49 }
  50
  51 void
  52 log_register(void (*cb)(int, const char*))
  53 {
  54         logh = cb;
  55 }
  56
  57
  58 static void
  59 logit(int pri, const char *fmt, ...)
  60 {
  61         va_list ap;
  62
  63         va_start(ap, fmt);
  64         vlog(pri, fmt, ap);
  65         va_end(ap);
  66 }
  67
  68 static char *
  69 date()
  70 {
  71         /* Return the current date as incomplete ISO 8601 (2012-12-12T16:13:30) */
  72         static char date[] = "2012-12-12T16:13:30";
  73         time_t t = time(NULL);
  74         struct tm *tmp = localtime(&t);
  75         strftime(date, sizeof(date), "%Y-%m-%dT%H:%M:%S", tmp);
  76         return date;
  77 }
  78
  79 static const char *
  80 translate(int fd, int priority)
  81 {
  82         /* Translate a syslog priority to a string. With colors if the output is a terminal. */
  83         int tty = isatty(fd);
  84         switch (tty) {
  85         case 1:
  86                 switch (priority) {
  87                 case LOG_EMERG:   return "\033[1;37;41m[EMRG]\033[0m";
  88                 case LOG_ALERT:   return "\033[1;37;41m[ALRT]\033[0m";
  89                 case LOG_CRIT:    return "\033[1;37;41m[CRIT]\033[0m";
  90                 case LOG_ERR:     return "\033[1;31m[ ERR]\033[0m";
  91                 case LOG_WARNING: return "\033[1;33m[WARN]\033[0m";
  92                 case LOG_NOTICE:  return "\033[1;34m[NOTI]\033[0m";
  93                 case LOG_INFO:    return "\033[1;34m[INFO]\033[0m";
  94                 case LOG_DEBUG:   return "\033[1;30m[ DBG]\033[0m";
  95                 }
  96                 break;
  97         default:
  98                 switch (priority) {
  99                 case LOG_EMERG:   return "[EMRG]";
 100                 case LOG_ALERT:   return "[ALRT]";
 101                 case LOG_CRIT:    return "[CRIT]";
 102                 case LOG_ERR:     return "[ ERR]";
 103                 case LOG_WARNING: return "[WARN]";
 104                 case LOG_NOTICE:  return "[NOTI]";
 105                 case LOG_INFO:    return "[INFO]";
 106                 case LOG_DEBUG:   return "[ DBG]";
 107                 }
 108         }
 109         return "[UNKN]";
 110 }
 111
 112 static void
 113 vlog(int pri, const char *fmt, va_list ap)
 114 {
 115         if (logh) {
 116                 char *result;
 117                 if (vasprintf(&result, fmt, ap) != -1) {
 118                         logh(pri, result);
 119                         return;
 120                 }
 121                 /* Otherwise, fallback to output on stderr. */
 122         }
 123         if (debug || logh) {
 124                 char *nfmt;
 125                 /* best effort in out of mem situations */
 126                 if (asprintf(&nfmt, "%s %s %s\n",
 127                         date(),
 128                         translate(STDERR_FILENO, pri),
 129                         fmt) == -1) {
 130                         vfprintf(stderr, fmt, ap);
 131                         fprintf(stderr, "\n");
 132                 } else {
 133                         vfprintf(stderr, nfmt, ap);
 134                         free(nfmt);
 135                 }
 136                 fflush(stderr);
 137         } else
 138                 vsyslog(pri, fmt, ap);
 139 }
 140
 141
 142 void
 143 log_warn(const char *emsg, ...)
 144 {
 145         char    *nfmt;
 146         va_list  ap;
 147
 148         /* best effort to even work in out of memory situations */
 149         if (emsg == NULL)
 150                 logit(LOG_WARNING, "%s", strerror(errno));
 151         else {
 152                 va_start(ap, emsg);
 153
 154                 if (asprintf(&nfmt, "%s: %s", emsg, strerror(errno)) == -1) {
 155                         /* we tried it... */
 156                         vlog(LOG_WARNING, emsg, ap);
 157                         logit(LOG_WARNING, "%s", strerror(errno));
 158                 } else {
 159                         vlog(LOG_WARNING, nfmt, ap);
 160                         free(nfmt);
 161                 }
 162                 va_end(ap);
 163         }
 164 }
 165
 166 void
 167 log_warnx(const char *emsg, ...)
 168 {
 169         va_list  ap;
 170
 171         va_start(ap, emsg);
 172         vlog(LOG_WARNING, emsg, ap);
 173         va_end(ap);
 174 }
 175
 176 void
 177 log_info(const char *emsg, ...)
 178 {
 179         va_list  ap;
 180
 181         if (debug > 1 || logh) {
 182                 va_start(ap, emsg);
 183                 vlog(LOG_INFO, emsg, ap);
 184                 va_end(ap);
 185         }
 186 }
 187
 188 void
 189 log_debug(const char *emsg, ...)
 190 {
 191         va_list  ap;
 192
 193         if (debug > 2 || logh) {
 194                 va_start(ap, emsg);
 195                 vlog(LOG_DEBUG, emsg, ap);
 196                 va_end(ap);
 197         }
 198 }
 199
 200 void
 201 fatal(const char *emsg)
 202 {
 203         if (emsg == NULL)
 204                 logit(LOG_CRIT, "fatal: %s", strerror(errno));
 205         else
 206                 if (errno)
 207                         logit(LOG_CRIT, "fatal: %s: %s",
 208                             emsg, strerror(errno));
 209                 else
 210                         logit(LOG_CRIT, "fatal: %s", emsg);
 211
 212         exit(1);
 213 }
 214
 215 void
 216 fatalx(const char *emsg)
 217 {
 218         errno = 0;
 219         fatal(emsg);
 220 }