logging.c

   1 /*
   2   chronyd/chronyc - Programs for keeping computer clocks accurate.
   3
   4  **********************************************************************
   5  * Copyright (C) Richard P. Curnow  1997-2003
   6  * Copyright (C) Miroslav Lichvar  2011-2014, 2018
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of version 2 of the GNU General Public License as
  10  * published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with this program; if not, write to the Free Software Foundation, Inc.,
  19  * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  20  *
  21  **********************************************************************
  22
  23   =======================================================================
  24
  25   Module to handle logging of diagnostic information
  26   */
  27
  28 #include "config.h"
  29
  30 #include "sysincl.h"
  31
  32 #include <syslog.h>
  33
  34 #include "conf.h"
  35 #include "logging.h"
  36 #include "util.h"
  37
  38 /* This is used by DEBUG_LOG macro */
  39 LOG_Severity log_min_severity = LOGS_INFO;
  40
  41 /* ================================================== */
  42 /* Flag indicating we have initialised */
  43 static int initialised = 0;
  44
  45 static FILE *file_log = NULL;
  46 static int system_log = 0;
  47
  48 static int parent_fd = 0;
  49
  50 struct LogFile {
  51   const char *name;
  52   const char *banner;
  53   FILE *file;
  54   unsigned long writes;
  55 };
  56
  57 static int n_filelogs = 0;
  58
  59 /* Increase this when adding a new logfile */
  60 #define MAX_FILELOGS 6
  61
  62 static struct LogFile logfiles[MAX_FILELOGS];
  63
  64 /* ================================================== */
  65 /* Init function */
  66
  67 void
  68 LOG_Initialise(void)
  69 {
  70   initialised = 1;
  71   LOG_OpenFileLog(NULL);
  72 }
  73
  74 /* ================================================== */
  75 /* Fini function */
  76
  77 void
  78 LOG_Finalise(void)
  79 {
  80   if (system_log)
  81     closelog();
  82
  83   if (file_log)
  84     fclose(file_log);
  85
  86   LOG_CycleLogFiles();
  87
  88   initialised = 0;
  89 }
  90
  91 /* ================================================== */
  92
  93 static void log_message(int fatal, LOG_Severity severity, const char *message)
  94 {
  95   if (system_log) {
  96     int priority;
  97     switch (severity) {
  98       case LOGS_DEBUG:
  99         priority = LOG_DEBUG;
 100         break;
 101       case LOGS_INFO:
 102         priority = LOG_INFO;
 103         break;
 104       case LOGS_WARN:
 105         priority = LOG_WARNING;
 106         break;
 107       case LOGS_ERR:
 108         priority = LOG_ERR;
 109         break;
 110       case LOGS_FATAL:
 111         priority = LOG_CRIT;
 112         break;
 113       default:
 114         assert(0);
 115     }
 116     syslog(priority, fatal ? "Fatal error : %s" : "%s", message);
 117   } else if (file_log) {
 118     fprintf(file_log, fatal ? "Fatal error : %s\n" : "%s\n", message);
 119   }
 120 }
 121
 122 /* ================================================== */
 123
 124 void LOG_Message(LOG_Severity severity,
 125 #if DEBUG > 0
 126                  int line_number, const char *filename, const char *function_name,
 127 #endif
 128                  const char *format, ...)
 129 {
 130   char buf[2048];
 131   va_list other_args;
 132   time_t t;
 133   struct tm *tm;
 134
 135   if (!system_log && file_log && severity >= log_min_severity) {
 136     /* Don't clutter up syslog with timestamps and internal debugging info */
 137     time(&t);
 138     tm = gmtime(&t);
 139     if (tm) {
 140       strftime(buf, sizeof (buf), "%Y-%m-%dT%H:%M:%SZ", tm);
 141       fprintf(file_log, "%s ", buf);
 142     }
 143 #if DEBUG > 0
 144     if (log_min_severity <= LOGS_DEBUG)
 145       fprintf(file_log, "%s:%d:(%s) ", filename, line_number, function_name);
 146 #endif
 147   }
 148
 149   va_start(other_args, format);
 150   vsnprintf(buf, sizeof(buf), format, other_args);
 151   va_end(other_args);
 152
 153   switch (severity) {
 154     case LOGS_DEBUG:
 155     case LOGS_INFO:
 156     case LOGS_WARN:
 157     case LOGS_ERR:
 158       if (severity >= log_min_severity)
 159         log_message(0, severity, buf);
 160       break;
 161     case LOGS_FATAL:
 162       if (severity >= log_min_severity)
 163         log_message(1, severity, buf);
 164
 165       /* Send the message also to the foreground process if it is
 166          still running, or stderr if it is still open */
 167       if (parent_fd > 0) {
 168         if (write(parent_fd, buf, strlen(buf) + 1) < 0)
 169           ; /* Not much we can do here */
 170       } else if (system_log && parent_fd == 0) {
 171         system_log = 0;
 172         log_message(1, severity, buf);
 173       }
 174       exit(1);
 175       break;
 176     default:
 177       assert(0);
 178   }
 179 }
 180
 181 /* ================================================== */
 182
 183 void
 184 LOG_OpenFileLog(const char *log_file)
 185 {
 186   FILE *f;
 187
 188   if (log_file) {
 189     f = UTI_OpenFile(NULL, log_file, NULL, 'A', 0640);
 190   } else {
 191     f = stderr;
 192   }
 193
 194   /* Enable line buffering */
 195   setvbuf(f, NULL, _IOLBF, BUFSIZ);
 196
 197   if (file_log && file_log != stderr)
 198     fclose(file_log);
 199
 200   file_log = f;
 201 }
 202
 203
 204 /* ================================================== */
 205
 206 void
 207 LOG_OpenSystemLog(void)
 208 {
 209   system_log = 1;
 210   openlog("chronyd", LOG_PID, LOG_DAEMON);
 211 }
 212
 213 /* ================================================== */
 214
 215 void LOG_SetMinSeverity(LOG_Severity severity)
 216 {
 217   /* Don't print any debug messages in a non-debug build */
 218   log_min_severity = CLAMP(DEBUG > 0 ? LOGS_DEBUG : LOGS_INFO, severity, LOGS_FATAL);
 219 }
 220
 221 /* ================================================== */
 222
 223 void
 224 LOG_SetParentFd(int fd)
 225 {
 226   parent_fd = fd;
 227   if (file_log == stderr)
 228     file_log = NULL;
 229 }
 230
 231 /* ================================================== */
 232
 233 void
 234 LOG_CloseParentFd()
 235 {
 236   if (parent_fd > 0)
 237     close(parent_fd);
 238   parent_fd = -1;
 239 }
 240
 241 /* ================================================== */
 242
 243 LOG_FileID
 244 LOG_FileOpen(const char *name, const char *banner)
 245 {
 246   assert(n_filelogs < MAX_FILELOGS);
 247
 248   logfiles[n_filelogs].name = name;
 249   logfiles[n_filelogs].banner = banner;
 250   logfiles[n_filelogs].file = NULL;
 251   logfiles[n_filelogs].writes = 0;
 252
 253   return n_filelogs++;
 254 }
 255
 256 /* ================================================== */
 257
 258 void
 259 LOG_FileWrite(LOG_FileID id, const char *format, ...)
 260 {
 261   va_list other_args;
 262   int banner;
 263
 264   if (id < 0 || id >= n_filelogs || !logfiles[id].name)
 265     return;
 266
 267   if (!logfiles[id].file) {
 268     char *logdir = CNF_GetLogDir();
 269
 270     if (logdir[0] == '\0') {
 271       LOG(LOGS_WARN, "logdir not specified");
 272       logfiles[id].name = NULL;
 273       return;
 274     }
 275
 276     logfiles[id].file = UTI_OpenFile(logdir, logfiles[id].name, ".log", 'a', 0644);
 277     if (!logfiles[id].file) {
 278       /* Disable the log */
 279       logfiles[id].name = NULL;
 280       return;
 281     }
 282   }
 283
 284   banner = CNF_GetLogBanner();
 285   if (banner && logfiles[id].writes++ % banner == 0) {
 286     char bannerline[256];
 287     int i, bannerlen;
 288
 289     bannerlen = MIN(strlen(logfiles[id].banner), sizeof (bannerline) - 1);
 290
 291     for (i = 0; i < bannerlen; i++)
 292       bannerline[i] = '=';
 293     bannerline[i] = '\0';
 294
 295     fprintf(logfiles[id].file, "%s\n", bannerline);
 296     fprintf(logfiles[id].file, "%s\n", logfiles[id].banner);
 297     fprintf(logfiles[id].file, "%s\n", bannerline);
 298   }
 299
 300   va_start(other_args, format);
 301   vfprintf(logfiles[id].file, format, other_args);
 302   va_end(other_args);
 303   fprintf(logfiles[id].file, "\n");
 304
 305   fflush(logfiles[id].file);
 306 }
 307
 308 /* ================================================== */
 309
 310 void
 311 LOG_CycleLogFiles(void)
 312 {
 313   LOG_FileID i;
 314
 315   for (i = 0; i < n_filelogs; i++) {
 316     if (logfiles[i].file)
 317       fclose(logfiles[i].file);
 318     logfiles[i].file = NULL;
 319     logfiles[i].writes = 0;
 320   }
 321 }
 322
 323 /* ================================================== */