os_win32/syslog_win32.cpp

   1 /*
   2  * os_win32/syslog_win32.cpp
   3  *
   4  * Home page of code is: http://smartmontools.sourceforge.net
   5  *
   6  * Copyright (C) 2004-12 Christian Franke <smartmontools-support@lists.sourceforge.net>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2, or (at your option)
  11  * any later version.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * (for example COPYING); If not, see <http://www.gnu.org/licenses/>.
  15  *
  16  */
  17
  18 // Win32 Emulation of syslog() for smartd
  19 // Writes to windows event log on NT4/2000/XP
  20 // (Register syslogevt.exe as event message file)
  21 // If facility is set to LOG_LOCAL[0-7], log is written to
  22 // file "<ident>.log", stdout, stderr, "<ident>[1-5].log".
  23
  24
  25 #include "syslog.h"
  26
  27 #include <stdlib.h>
  28 #include <stdio.h>
  29 #include <time.h>
  30 #include <errno.h>
  31 #include <process.h> // getpid()
  32
  33 #define WIN32_LEAN_AND_MEAN
  34 #include <windows.h> // RegisterEventSourceA(), ReportEventA(), ...
  35
  36 const char *syslog_win32_cpp_cvsid = "$Id: syslog_win32.cpp 3575 2012-07-19 21:32:56Z chrfranke $"
  37   SYSLOG_H_CVSID;
  38
  39 #ifdef _MSC_VER
  40 // MSVC
  41 #define snprintf _snprintf
  42 #define vsnprintf _vsnprintf
  43 #endif
  44
  45 #define ARGUSED(x) ((void)(x))
  46
  47
  48 #ifndef _MT
  49 //MT runtime not necessary, because thread uses no unsafe lib functions
  50 //#error Program must be linked with multithreaded runtime library
  51 #endif
  52
  53
  54 #ifdef TESTEVT
  55 // Redirect event log to stdout for testing
  56
  57 static BOOL Test_ReportEventA(HANDLE h, WORD type, WORD cat, DWORD id, PSID usid,
  58                                                 WORD nstrings, WORD datasize, LPCTSTR * strings, LPVOID data)
  59 {
  60         int i;
  61         printf("%u %lu:%s", type, id, nstrings != 1?"\n":"");
  62         for (i = 0; i < nstrings; i++)
  63                 printf(" \"%s\"\n", strings[i]);
  64         fflush(stdout);
  65         return TRUE;
  66 }
  67
  68 HANDLE Test_RegisterEventSourceA(LPCTSTR server, LPCTSTR source)
  69 {
  70         return (HANDLE)42;
  71 }
  72
  73 #define ReportEventA Test_ReportEventA
  74 #define RegisterEventSourceA Test_RegisterEventSourceA
  75 #endif // TESTEVT
  76
  77
  78 // Event message ids,
  79 // should be identical to MSG_SYSLOG* in "syslogevt.h"
  80 // (generated by "mc" from "syslogevt.mc")
  81 #define MSG_SYSLOG                       0x00000000L
  82 #define MSG_SYSLOG_01                    0x00000001L
  83 // ...
  84 #define MSG_SYSLOG_10                    0x0000000AL
  85
  86 static char sl_ident[100];
  87 static char sl_logpath[sizeof(sl_ident) + sizeof("0.log")-1];
  88 static FILE * sl_logfile;
  89 static char sl_pidstr[16];
  90 static HANDLE sl_hevtsrc;
  91
  92
  93 // Ring buffer for event log output via thread
  94 #define MAXLINES 10
  95 #define LINELEN 200
  96
  97 static HANDLE evt_hthread;
  98 static char evt_lines[MAXLINES][LINELEN+1];
  99 static int evt_priorities[MAXLINES];
 100 static volatile int evt_timeout;
 101 static int evt_index_in, evt_index_out;
 102 static HANDLE evt_wait_in, evt_wait_out;
 103
 104
 105 // Map syslog priority to event type
 106
 107 static WORD pri2evtype(int priority)
 108 {
 109         switch (priority) {
 110                 default:
 111                 case LOG_EMERG: case LOG_ALERT:
 112                 case LOG_CRIT:  case LOG_ERR:
 113                         return EVENTLOG_ERROR_TYPE;
 114                 case LOG_WARNING:
 115                         return EVENTLOG_WARNING_TYPE;
 116                 case LOG_NOTICE: case LOG_INFO:
 117                 case LOG_DEBUG:
 118                         return EVENTLOG_INFORMATION_TYPE;
 119         }
 120 }
 121
 122
 123 // Map syslog priority to string
 124
 125 static const char * pri2text(int priority)
 126 {
 127         switch (priority) {
 128                 case LOG_EMERG:   return "EMERG";
 129                 case LOG_ALERT:   return "ALERT";
 130                 case LOG_CRIT:    return "CRIT";
 131                 default:
 132                 case LOG_ERR:     return "ERROR";
 133                 case LOG_WARNING: return "Warn";
 134                 case LOG_NOTICE:  return "Note";
 135                 case LOG_INFO:    return "Info";
 136                 case LOG_DEBUG:   return "Debug";
 137         }
 138 }
 139
 140
 141 // Output cnt events from ring buffer
 142
 143 static void report_events(int cnt)
 144 {
 145         const char * msgs[3+MAXLINES];
 146
 147         int i, pri;
 148         if (cnt <= 0)
 149                 return;
 150         if (cnt > MAXLINES)
 151                 cnt = MAXLINES;
 152
 153         pri = evt_priorities[evt_index_out];
 154
 155         msgs[0] = sl_ident;
 156         msgs[1] = sl_pidstr;
 157         msgs[2] = pri2text(pri);
 158         for (i = 0; i < cnt; i++) {
 159                 //assert(evt_priorities[evt_index_out] == pri);
 160                 msgs[3+i] = evt_lines[evt_index_out];
 161                 if (++evt_index_out >= MAXLINES)
 162                         evt_index_out = 0;
 163         }
 164         ReportEventA(sl_hevtsrc,
 165                 pri2evtype(pri), // type
 166                 0, MSG_SYSLOG+cnt,    // category, message id
 167                 NULL,                 // no security id
 168                 (WORD)(3+cnt), 0,     // 3+cnt strings, ...
 169                 msgs, NULL);          // ...          , no data
 170 }
 171
 172
 173 // Thread to combine several syslog lines into one event log entry
 174
 175 static ULONG WINAPI event_logger_thread(LPVOID arg)
 176 {
 177         int cnt;
 178         ARGUSED(arg);
 179
 180         cnt = 0;
 181         for (;;) {
 182                 // Wait for first line ...
 183                 int prior, i, rest;
 184                 if (cnt == 0) {
 185                         if (WaitForSingleObject(evt_wait_out, (evt_timeout? INFINITE : 0)) != WAIT_OBJECT_0)
 186                                 break;
 187                         cnt = 1;
 188                 }
 189
 190                 // ... wait some time for more lines with same prior
 191                 i = evt_index_out;
 192                 prior = evt_priorities[i];
 193                 rest = 0;
 194                 while (cnt < MAXLINES) {
 195                         long timeout =
 196                                 evt_timeout * ((1000L * (MAXLINES-cnt+1))/MAXLINES);
 197                         if (WaitForSingleObject(evt_wait_out, timeout) != WAIT_OBJECT_0)
 198                                 break;
 199                         if (++i >= MAXLINES)
 200                                 i = 0;
 201                         if (evt_priorities[i] != prior) {
 202                                 rest = 1;
 203                                 break;
 204                         }
 205                         cnt++;
 206                 }
 207
 208                 // Output all in one event log entry
 209                 report_events(cnt);
 210
 211                 // Signal space
 212                 if (!ReleaseSemaphore(evt_wait_in, cnt, NULL))
 213                         break;
 214                 cnt = rest;
 215         }
 216         return 0;
 217 }
 218
 219
 220 static void on_exit_event_logger(void)
 221 {
 222         // Output lines immediate if exiting
 223         evt_timeout = 0;
 224         // Wait for thread to finish
 225         WaitForSingleObject(evt_hthread, 1000L);
 226         CloseHandle(evt_hthread);
 227 #if 0
 228         if (sl_hevtsrc) {
 229                 DeregisterEventSource(sl_hevtsrc); sl_hevtsrc = 0;
 230         }
 231 #else
 232         // Leave event message source open to prevent losing messages during shutdown
 233 #endif
 234 }
 235
 236
 237 static int start_event_logger()
 238 {
 239         DWORD tid;
 240         evt_timeout = 1;
 241         if (   !(evt_wait_in  = CreateSemaphore(NULL,  MAXLINES, MAXLINES, NULL))
 242                 || !(evt_wait_out = CreateSemaphore(NULL,         0, MAXLINES, NULL))) {
 243                 fprintf(stderr,"CreateSemaphore failed, Error=%ld\n", GetLastError());
 244                 return -1;
 245         }
 246         if (!(evt_hthread = CreateThread(NULL, 0, event_logger_thread, NULL, 0, &tid))) {
 247                 fprintf(stderr,"CreateThread failed, Error=%ld\n", GetLastError());
 248                 return -1;
 249         }
 250         atexit(on_exit_event_logger);
 251         return 0;
 252 }
 253
 254
 255 // Write lines to event log ring buffer
 256
 257 static void write_event_log(int priority, const char * lines)
 258 {
 259         int cnt = 0;
 260         int i;
 261         for (i = 0; lines[i]; i++) {
 262                 int len = 0;
 263                 while (lines[i+len] && lines[i+len] != '\n')
 264                         len++;
 265                         ;
 266                 if (len > 0) {
 267                         // Wait for space
 268                         if (WaitForSingleObject(evt_wait_in, INFINITE) != WAIT_OBJECT_0)
 269                                 return;
 270                         // Copy line
 271                         evt_priorities[evt_index_in] = priority;
 272                         memcpy(evt_lines[evt_index_in], lines+i, (len < LINELEN ? len : LINELEN));
 273                         if (len < LINELEN)
 274                                 evt_lines[evt_index_in][len] = 0;
 275                         if (++evt_index_in >= MAXLINES)
 276                                 evt_index_in = 0;
 277                         // Signal avail if ring buffer full
 278                         if (++cnt >= MAXLINES) {
 279                                 ReleaseSemaphore(evt_wait_out, cnt, NULL);
 280                                 cnt = 0;
 281                         }
 282                         i += len;
 283                 }
 284                 if (!lines[i])
 285                         break;
 286         }
 287
 288         // Signal avail
 289         if (cnt > 0)
 290                 ReleaseSemaphore(evt_wait_out, cnt, NULL);
 291         Sleep(1);
 292 }
 293
 294
 295 // Write lines to logfile
 296
 297 static void write_logfile(FILE * f, int priority, const char * lines)
 298 {
 299         time_t now; char stamp[sizeof("2004-04-04 10:00:00")+13];
 300         int i;
 301
 302         now = time((time_t*)0);
 303         if (!strftime(stamp, sizeof(stamp)-1, "%Y-%m-%d %H:%M:%S", localtime(&now)))
 304                 strcpy(stamp,"?");
 305
 306         for (i = 0; lines[i]; i++) {
 307                 int len = 0;
 308                 while (lines[i+len] && lines[i+len] != '\n')
 309                         len++;
 310                 if (len > 0) {
 311                         fprintf(f, "%s %s[%s]: %-5s: ",
 312                                 stamp, sl_ident, sl_pidstr, pri2text(priority));
 313                         fwrite(lines+i, len, 1, f);
 314                         fputc('\n', f);
 315                         i += len;
 316                 }
 317                 if (!lines[i])
 318                         break;
 319         }
 320 }
 321
 322
 323 void openlog(const char *ident, int logopt, int facility)
 324 {
 325         int pid;
 326         if (sl_logpath[0] || sl_logfile || sl_hevtsrc)
 327                 return; // Already open
 328
 329         strncpy(sl_ident, ident, sizeof(sl_ident)-1);
 330         // logopt==LOG_PID assumed
 331         ARGUSED(logopt);
 332         pid = getpid();
 333         if (snprintf(sl_pidstr, sizeof(sl_pidstr)-1, (pid >= 0 ? "%d" : "0x%X"), pid) < 0)
 334                 strcpy(sl_pidstr,"?");
 335
 336         if (facility == LOG_LOCAL0) // "ident.log"
 337                 strcat(strcpy(sl_logpath, sl_ident), ".log");
 338         else if (facility == LOG_LOCAL1) // stdout
 339                 sl_logfile = stdout;
 340         else if (facility == LOG_LOCAL2) // stderr
 341                 sl_logfile = stderr;
 342         else if (LOG_LOCAL2 < facility && facility <= LOG_LOCAL7) { // "ident[1-5].log"
 343                 snprintf(sl_logpath, sizeof(sl_logpath)-1, "%s%d.log",
 344                         sl_ident, LOG_FAC(facility)-LOG_FAC(LOG_LOCAL2));
 345         }
 346         else // Assume LOG_DAEMON, use event log if possible, else "ident.log"
 347         if (!(sl_hevtsrc = RegisterEventSourceA(NULL/*localhost*/, sl_ident))) {
 348                 // Cannot open => Use logfile
 349                 long err = GetLastError();
 350                 strcat(strcpy(sl_logpath, sl_ident), ".log");
 351                 fprintf(stderr, "%s: Cannot register event source (Error=%ld), writing to %s\n",
 352                         sl_ident, err, sl_logpath);
 353         }
 354         else {
 355                 // Start event log thread
 356                 start_event_logger();
 357         }
 358         //assert(sl_logpath[0] || sl_logfile || sl_hevtsrc);
 359
 360 }
 361
 362
 363 void closelog()
 364 {
 365 }
 366
 367
 368 void vsyslog(int priority, const char * message, va_list args)
 369 {
 370         char buffer[1000];
 371
 372         // Translation of %m to error text not supported yet
 373         if (strstr(message, "%m"))
 374                 message = "Internal error: \"%%m\" in log message";
 375
 376         // Format message
 377         if (vsnprintf(buffer, sizeof(buffer)-1, message, args) < 0)
 378                 strcpy(buffer, "Internal Error: buffer overflow");
 379
 380         if (sl_hevtsrc) {
 381                 // Write to event log
 382                 write_event_log(priority, buffer);
 383         }
 384         else if (sl_logfile) {
 385                 // Write to stdout/err
 386                 write_logfile(sl_logfile, priority, buffer);
 387                 fflush(sl_logfile);
 388         }
 389         else if (sl_logpath[0]) {
 390                 // Append to logfile
 391                 FILE * f;
 392                 if (!(f = fopen(sl_logpath, "a")))
 393                         return;
 394                 write_logfile(f, priority, buffer);
 395                 fclose(f);
 396         }
 397 }
 398
 399
 400 #ifdef TEST
 401 // Test program
 402
 403 void syslog(int priority, const char *message, ...)
 404 {
 405         va_list args;
 406         va_start(args, message);
 407         vsyslog(priority, message, args);
 408         va_end(args);
 409 }
 410
 411 int main(int argc, char* argv[])
 412 {
 413         int i;
 414         openlog(argc < 2 ? "test" : argv[1], LOG_PID, (argc < 3 ? LOG_DAEMON : LOG_LOCAL1));
 415         syslog(LOG_INFO,    "Info\n");
 416         syslog(LOG_WARNING, "Warning %d\n\n", 42);
 417         syslog(LOG_ERR,     "Error %s", "Fatal");
 418         for (i = 0; i < 100; i++) {
 419                 char buf[LINELEN];
 420                 if (i % 13 == 0)
 421                         Sleep(1000L);
 422                 sprintf(buf, "Log Line %d\n", i);
 423                 syslog(i % 17 ? LOG_INFO : LOG_ERR, buf);
 424         }
 425         closelog();
 426         return 0;
 427 }
 428
 429 #endif