PostgreSQL Source Code git master
syslogger.h File Reference
#include <limits.h>
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Data Structures

struct  PipeProtoHeader
 
union  PipeProtoChunk
 

Macros

#define PIPE_CHUNK_SIZE   512
 
#define PIPE_HEADER_SIZE   offsetof(PipeProtoHeader, data)
 
#define PIPE_MAX_PAYLOAD   ((int) (PIPE_CHUNK_SIZE - PIPE_HEADER_SIZE))
 
#define PIPE_PROTO_IS_LAST   0x01 /* last chunk of message? */
 
#define PIPE_PROTO_DEST_STDERR   0x10
 
#define PIPE_PROTO_DEST_CSVLOG   0x20
 
#define PIPE_PROTO_DEST_JSONLOG   0x40
 
#define LOG_METAINFO_DATAFILE   "current_logfiles"
 
#define LOG_METAINFO_DATAFILE_TMP   LOG_METAINFO_DATAFILE ".tmp"
 

Functions

int SysLogger_Start (int child_slot)
 
void write_syslogger_file (const char *buffer, int count, int destination)
 
pg_noreturn void SysLoggerMain (const void *startup_data, size_t startup_data_len)
 
bool CheckLogrotateSignal (void)
 
void RemoveLogrotateSignalFiles (void)
 

Variables

PGDLLIMPORT bool Logging_collector
 
PGDLLIMPORT int Log_RotationAge
 
PGDLLIMPORT int Log_RotationSize
 
PGDLLIMPORT char * Log_directory
 
PGDLLIMPORT char * Log_filename
 
PGDLLIMPORT bool Log_truncate_on_rotation
 
PGDLLIMPORT int Log_file_mode
 
PGDLLIMPORT int syslogPipe [2]
 

Macro Definition Documentation

◆ LOG_METAINFO_DATAFILE

#define LOG_METAINFO_DATAFILE   "current_logfiles"

Definition at line 102 of file syslogger.h.

◆ LOG_METAINFO_DATAFILE_TMP

#define LOG_METAINFO_DATAFILE_TMP   LOG_METAINFO_DATAFILE ".tmp"

Definition at line 103 of file syslogger.h.

◆ PIPE_CHUNK_SIZE

#define PIPE_CHUNK_SIZE   512

Definition at line 41 of file syslogger.h.

◆ PIPE_HEADER_SIZE

#define PIPE_HEADER_SIZE   offsetof(PipeProtoHeader, data)

Definition at line 59 of file syslogger.h.

◆ PIPE_MAX_PAYLOAD

#define PIPE_MAX_PAYLOAD   ((int) (PIPE_CHUNK_SIZE - PIPE_HEADER_SIZE))

Definition at line 60 of file syslogger.h.

◆ PIPE_PROTO_DEST_CSVLOG

#define PIPE_PROTO_DEST_CSVLOG   0x20

Definition at line 66 of file syslogger.h.

◆ PIPE_PROTO_DEST_JSONLOG

#define PIPE_PROTO_DEST_JSONLOG   0x40

Definition at line 67 of file syslogger.h.

◆ PIPE_PROTO_DEST_STDERR

#define PIPE_PROTO_DEST_STDERR   0x10

Definition at line 65 of file syslogger.h.

◆ PIPE_PROTO_IS_LAST

#define PIPE_PROTO_IS_LAST   0x01 /* last chunk of message? */

Definition at line 63 of file syslogger.h.

Function Documentation

◆ CheckLogrotateSignal()

bool CheckLogrotateSignal ( void  )

Definition at line 1574 of file syslogger.c.

1575{
1576 struct stat stat_buf;
1577
1578 if (stat(LOGROTATE_SIGNAL_FILE, &stat_buf) == 0)
1579 return true;
1580
1581 return false;
1582}
#define LOGROTATE_SIGNAL_FILE
Definition: syslogger.c:63
#define stat
Definition: win32_port.h:274

References LOGROTATE_SIGNAL_FILE, and stat.

Referenced by process_pm_pmsignal().

◆ RemoveLogrotateSignalFiles()

void RemoveLogrotateSignalFiles ( void  )

Definition at line 1588 of file syslogger.c.

1589{
1590 unlink(LOGROTATE_SIGNAL_FILE);
1591}

References LOGROTATE_SIGNAL_FILE.

Referenced by PostmasterMain(), and process_pm_pmsignal().

◆ SysLogger_Start()

int SysLogger_Start ( int  child_slot)

Definition at line 593 of file syslogger.c.

594{
595 pid_t sysloggerPid;
596 char *filename;
597#ifdef EXEC_BACKEND
598 SysloggerStartupData startup_data;
599#endif /* EXEC_BACKEND */
600
602
603 /*
604 * If first time through, create the pipe which will receive stderr
605 * output.
606 *
607 * If the syslogger crashes and needs to be restarted, we continue to use
608 * the same pipe (indeed must do so, since extant backends will be writing
609 * into that pipe).
610 *
611 * This means the postmaster must continue to hold the read end of the
612 * pipe open, so we can pass it down to the reincarnated syslogger. This
613 * is a bit klugy but we have little choice.
614 *
615 * Also note that we don't bother counting the pipe FDs by calling
616 * Reserve/ReleaseExternalFD. There's no real need to account for them
617 * accurately in the postmaster or syslogger process, and both ends of the
618 * pipe will wind up closed in all other postmaster children.
619 */
620#ifndef WIN32
621 if (syslogPipe[0] < 0)
622 {
623 if (pipe(syslogPipe) < 0)
626 errmsg("could not create pipe for syslog: %m")));
627 }
628#else
629 if (!syslogPipe[0])
630 {
631 SECURITY_ATTRIBUTES sa;
632
633 memset(&sa, 0, sizeof(SECURITY_ATTRIBUTES));
634 sa.nLength = sizeof(SECURITY_ATTRIBUTES);
635 sa.bInheritHandle = TRUE;
636
637 if (!CreatePipe(&syslogPipe[0], &syslogPipe[1], &sa, 32768))
640 errmsg("could not create pipe for syslog: %m")));
641 }
642#endif
643
644 /*
645 * Create log directory if not present; ignore errors
646 */
648
649 /*
650 * The initial logfile is created right in the postmaster, to verify that
651 * the Log_directory is writable. We save the reference time so that the
652 * syslogger child process can recompute this file name.
653 *
654 * It might look a bit strange to re-do this during a syslogger restart,
655 * but we must do so since the postmaster closed syslogFile after the
656 * previous fork (and remembering that old file wouldn't be right anyway).
657 * Note we always append here, we won't overwrite any existing file. This
658 * is consistent with the normal rules, because by definition this is not
659 * a time-based rotation.
660 */
661 first_syslogger_file_time = time(NULL);
662
664
665 syslogFile = logfile_open(filename, "a", false);
666
668
669 /*
670 * Likewise for the initial CSV log file, if that's enabled. (Note that
671 * we open syslogFile even when only CSV output is nominally enabled,
672 * since some code paths will write to syslogFile anyway.)
673 */
675 {
677
678 csvlogFile = logfile_open(filename, "a", false);
679
681 }
682
683 /*
684 * Likewise for the initial JSON log file, if that's enabled. (Note that
685 * we open syslogFile even when only JSON output is nominally enabled,
686 * since some code paths will write to syslogFile anyway.)
687 */
689 {
691
692 jsonlogFile = logfile_open(filename, "a", false);
693
695 }
696
697#ifdef EXEC_BACKEND
698 startup_data.syslogFile = syslogger_fdget(syslogFile);
699 startup_data.csvlogFile = syslogger_fdget(csvlogFile);
700 startup_data.jsonlogFile = syslogger_fdget(jsonlogFile);
701 sysloggerPid = postmaster_child_launch(B_LOGGER, child_slot,
702 &startup_data, sizeof(startup_data), NULL);
703#else
704 sysloggerPid = postmaster_child_launch(B_LOGGER, child_slot,
705 NULL, 0, NULL);
706#endif /* EXEC_BACKEND */
707
708 if (sysloggerPid == -1)
709 {
710 ereport(LOG,
711 (errmsg("could not fork system logger: %m")));
712 return 0;
713 }
714
715 /* success, in postmaster */
716
717 /* now we redirect stderr, if not done already */
718 if (!redirection_done)
719 {
720#ifdef WIN32
721 int fd;
722#endif
723
724 /*
725 * Leave a breadcrumb trail when redirecting, in case the user forgets
726 * that redirection is active and looks only at the original stderr
727 * target file.
728 */
729 ereport(LOG,
730 (errmsg("redirecting log output to logging collector process"),
731 errhint("Future log output will appear in directory \"%s\".",
732 Log_directory)));
733
734#ifndef WIN32
735 fflush(stdout);
736 if (dup2(syslogPipe[1], STDOUT_FILENO) < 0)
739 errmsg("could not redirect stdout: %m")));
740 fflush(stderr);
741 if (dup2(syslogPipe[1], STDERR_FILENO) < 0)
744 errmsg("could not redirect stderr: %m")));
745 /* Now we are done with the write end of the pipe. */
746 close(syslogPipe[1]);
747 syslogPipe[1] = -1;
748#else
749
750 /*
751 * open the pipe in binary mode and make sure stderr is binary after
752 * it's been dup'ed into, to avoid disturbing the pipe chunking
753 * protocol.
754 */
755 fflush(stderr);
756 fd = _open_osfhandle((intptr_t) syslogPipe[1],
757 _O_APPEND | _O_BINARY);
758 if (dup2(fd, STDERR_FILENO) < 0)
761 errmsg("could not redirect stderr: %m")));
762 close(fd);
763 _setmode(STDERR_FILENO, _O_BINARY);
764
765 /*
766 * Now we are done with the write end of the pipe. CloseHandle() must
767 * not be called because the preceding close() closes the underlying
768 * handle.
769 */
770 syslogPipe[1] = 0;
771#endif
772 redirection_done = true;
773 }
774
775 /* postmaster will never write the file(s); close 'em */
776 fclose(syslogFile);
777 syslogFile = NULL;
778 if (csvlogFile != NULL)
779 {
780 fclose(csvlogFile);
781 csvlogFile = NULL;
782 }
783 if (jsonlogFile != NULL)
784 {
785 fclose(jsonlogFile);
786 jsonlogFile = NULL;
787 }
788 return (int) sysloggerPid;
789}
int errcode_for_socket_access(void)
Definition: elog.c:953
int errcode_for_file_access(void)
Definition: elog.c:876
int Log_destination
Definition: elog.c:110
int errhint(const char *fmt,...)
Definition: elog.c:1317
int errmsg(const char *fmt,...)
Definition: elog.c:1070
#define LOG
Definition: elog.h:31
#define FATAL
Definition: elog.h:41
#define LOG_DESTINATION_JSONLOG
Definition: elog.h:488
#define ereport(elevel,...)
Definition: elog.h:149
#define LOG_DESTINATION_CSVLOG
Definition: elog.h:487
int MakePGDirectory(const char *directoryName)
Definition: fd.c:3936
Assert(PointerIsAligned(start, uint64))
#define close(a)
Definition: win32.h:12
pid_t postmaster_child_launch(BackendType child_type, int child_slot, const void *startup_data, size_t startup_data_len, ClientSocket *client_sock)
void pfree(void *pointer)
Definition: mcxt.c:1524
@ B_LOGGER
Definition: miscadmin.h:373
static char * filename
Definition: pg_dumpall.c:124
bool redirection_done
Definition: postmaster.c:374
static int fd(const char *x, int i)
Definition: preproc-init.c:105
char * Log_directory
Definition: syslogger.c:73
static char * logfile_getname(pg_time_t timestamp, const char *suffix)
Definition: syslogger.c:1412
static FILE * logfile_open(const char *filename, const char *mode, bool allow_errors)
Definition: syslogger.c:1219
NON_EXEC_STATIC pg_time_t first_syslogger_file_time
Definition: syslogger.c:87
int syslogPipe[2]
Definition: syslogger.c:114
static FILE * syslogFile
Definition: syslogger.c:84
bool Logging_collector
Definition: syslogger.c:70
static FILE * csvlogFile
Definition: syslogger.c:85
static FILE * jsonlogFile
Definition: syslogger.c:86
#define STDOUT_FILENO
Definition: unistd.h:8
#define STDERR_FILENO
Definition: unistd.h:9

References Assert(), B_LOGGER, close, csvlogFile, SysloggerStartupData::csvlogFile, ereport, errcode_for_file_access(), errcode_for_socket_access(), errhint(), errmsg(), FATAL, fd(), filename, first_syslogger_file_time, jsonlogFile, SysloggerStartupData::jsonlogFile, LOG, Log_destination, LOG_DESTINATION_CSVLOG, LOG_DESTINATION_JSONLOG, Log_directory, logfile_getname(), logfile_open(), Logging_collector, MakePGDirectory(), pfree(), postmaster_child_launch(), redirection_done, STDERR_FILENO, generate_unaccent_rules::stdout, STDOUT_FILENO, syslogFile, SysloggerStartupData::syslogFile, and syslogPipe.

Referenced by StartSysLogger().

◆ SysLoggerMain()

pg_noreturn void SysLoggerMain ( const void *  startup_data,
size_t  startup_data_len 
)

Definition at line 165 of file syslogger.c.

166{
167#ifndef WIN32
168 char logbuffer[READ_BUF_SIZE];
169 int bytes_in_logbuffer = 0;
170#endif
171 char *currentLogDir;
172 char *currentLogFilename;
173 int currentLogRotationAge;
175 WaitEventSet *wes;
176
177 /*
178 * Re-open the error output files that were opened by SysLogger_Start().
179 *
180 * We expect this will always succeed, which is too optimistic, but if it
181 * fails there's not a lot we can do to report the problem anyway. As
182 * coded, we'll just crash on a null pointer dereference after failure...
183 */
184#ifdef EXEC_BACKEND
185 {
186 const SysloggerStartupData *slsdata = startup_data;
187
188 Assert(startup_data_len == sizeof(*slsdata));
189 syslogFile = syslogger_fdopen(slsdata->syslogFile);
190 csvlogFile = syslogger_fdopen(slsdata->csvlogFile);
191 jsonlogFile = syslogger_fdopen(slsdata->jsonlogFile);
192 }
193#else
194 Assert(startup_data_len == 0);
195#endif
196
197 /*
198 * Now that we're done reading the startup data, release postmaster's
199 * working memory context.
200 */
202 {
204 PostmasterContext = NULL;
205 }
206
208
210 init_ps_display(NULL);
211
212 /*
213 * If we restarted, our stderr is already redirected into our own input
214 * pipe. This is of course pretty useless, not to mention that it
215 * interferes with detecting pipe EOF. Point stderr to /dev/null. This
216 * assumes that all interesting messages generated in the syslogger will
217 * come through elog.c and will be sent to write_syslogger_file.
218 */
220 {
221 int fd = open(DEVNULL, O_WRONLY, 0);
222
223 /*
224 * The closes might look redundant, but they are not: we want to be
225 * darn sure the pipe gets closed even if the open failed. We can
226 * survive running with stderr pointing nowhere, but we can't afford
227 * to have extra pipe input descriptors hanging around.
228 *
229 * As we're just trying to reset these to go to DEVNULL, there's not
230 * much point in checking for failure from the close/dup2 calls here,
231 * if they fail then presumably the file descriptors are closed and
232 * any writes will go into the bitbucket anyway.
233 */
236 if (fd != -1)
237 {
238 (void) dup2(fd, STDOUT_FILENO);
239 (void) dup2(fd, STDERR_FILENO);
240 close(fd);
241 }
242 }
243
244 /*
245 * Syslogger's own stderr can't be the syslogPipe, so set it back to text
246 * mode if we didn't just close it. (It was set to binary in
247 * SubPostmasterMain).
248 */
249#ifdef WIN32
250 else
251 _setmode(STDERR_FILENO, _O_TEXT);
252#endif
253
254 /*
255 * Also close our copy of the write end of the pipe. This is needed to
256 * ensure we can detect pipe EOF correctly. (But note that in the restart
257 * case, the postmaster already did this.)
258 */
259#ifndef WIN32
260 if (syslogPipe[1] >= 0)
261 close(syslogPipe[1]);
262 syslogPipe[1] = -1;
263#else
264 if (syslogPipe[1])
265 CloseHandle(syslogPipe[1]);
266 syslogPipe[1] = 0;
267#endif
268
269 /*
270 * Properly accept or ignore signals the postmaster might send us
271 *
272 * Note: we ignore all termination signals, and instead exit only when all
273 * upstream processes are gone, to ensure we don't miss any dying gasps of
274 * broken backends...
275 */
276
277 pqsignal(SIGHUP, SignalHandlerForConfigReload); /* set flag to read config
278 * file */
279 pqsignal(SIGINT, SIG_IGN);
280 pqsignal(SIGTERM, SIG_IGN);
281 pqsignal(SIGQUIT, SIG_IGN);
282 pqsignal(SIGALRM, SIG_IGN);
283 pqsignal(SIGPIPE, SIG_IGN);
284 pqsignal(SIGUSR1, sigUsr1Handler); /* request log rotation */
285 pqsignal(SIGUSR2, SIG_IGN);
286
287 /*
288 * Reset some signals that are accepted by postmaster but not here
289 */
290 pqsignal(SIGCHLD, SIG_DFL);
291
292 sigprocmask(SIG_SETMASK, &UnBlockSig, NULL);
293
294#ifdef WIN32
295 /* Fire up separate data transfer thread */
296 InitializeCriticalSection(&sysloggerSection);
297 EnterCriticalSection(&sysloggerSection);
298
299 threadHandle = (HANDLE) _beginthreadex(NULL, 0, pipeThread, NULL, 0, NULL);
300 if (threadHandle == 0)
301 elog(FATAL, "could not create syslogger data transfer thread: %m");
302#endif /* WIN32 */
303
304 /*
305 * Remember active logfiles' name(s). We recompute 'em from the reference
306 * time because passing down just the pg_time_t is a lot cheaper than
307 * passing a whole file path in the EXEC_BACKEND case.
308 */
310 if (csvlogFile != NULL)
312 if (jsonlogFile != NULL)
314
315 /* remember active logfile parameters */
316 currentLogDir = pstrdup(Log_directory);
317 currentLogFilename = pstrdup(Log_filename);
318 currentLogRotationAge = Log_RotationAge;
319 /* set next planned rotation time */
322
323 /*
324 * Reset whereToSendOutput, as the postmaster will do (but hasn't yet, at
325 * the point where we forked). This prevents duplicate output of messages
326 * from syslogger itself.
327 */
329
330 /*
331 * Set up a reusable WaitEventSet object we'll use to wait for our latch,
332 * and (except on Windows) our socket.
333 *
334 * Unlike all other postmaster child processes, we'll ignore postmaster
335 * death because we want to collect final log output from all backends and
336 * then exit last. We'll do that by running until we see EOF on the
337 * syslog pipe, which implies that all other backends have exited
338 * (including the postmaster).
339 */
340 wes = CreateWaitEventSet(NULL, 2);
342#ifndef WIN32
343 AddWaitEventToSet(wes, WL_SOCKET_READABLE, syslogPipe[0], NULL, NULL);
344#endif
345
346 /* main worker loop */
347 for (;;)
348 {
349 bool time_based_rotation = false;
350 int size_rotation_for = 0;
351 long cur_timeout;
352 WaitEvent event;
353
354#ifndef WIN32
355 int rc;
356#endif
357
358 /* Clear any already-pending wakeups */
360
361 /*
362 * Process any requests or signals received recently.
363 */
365 {
366 ConfigReloadPending = false;
368
369 /*
370 * Check if the log directory or filename pattern changed in
371 * postgresql.conf. If so, force rotation to make sure we're
372 * writing the logfiles in the right place.
373 */
374 if (strcmp(Log_directory, currentLogDir) != 0)
375 {
376 pfree(currentLogDir);
377 currentLogDir = pstrdup(Log_directory);
378 rotation_requested = true;
379
380 /*
381 * Also, create new directory if not present; ignore errors
382 */
384 }
385 if (strcmp(Log_filename, currentLogFilename) != 0)
386 {
387 pfree(currentLogFilename);
388 currentLogFilename = pstrdup(Log_filename);
389 rotation_requested = true;
390 }
391
392 /*
393 * Force a rotation if CSVLOG output was just turned on or off and
394 * we need to open or close csvlogFile accordingly.
395 */
397 (csvlogFile != NULL))
398 rotation_requested = true;
399
400 /*
401 * Force a rotation if JSONLOG output was just turned on or off
402 * and we need to open or close jsonlogFile accordingly.
403 */
405 (jsonlogFile != NULL))
406 rotation_requested = true;
407
408 /*
409 * If rotation time parameter changed, reset next rotation time,
410 * but don't immediately force a rotation.
411 */
412 if (currentLogRotationAge != Log_RotationAge)
413 {
414 currentLogRotationAge = Log_RotationAge;
416 }
417
418 /*
419 * If we had a rotation-disabling failure, re-enable rotation
420 * attempts after SIGHUP, and force one immediately.
421 */
423 {
424 rotation_disabled = false;
425 rotation_requested = true;
426 }
427
428 /*
429 * Force rewriting last log filename when reloading configuration.
430 * Even if rotation_requested is false, log_destination may have
431 * been changed and we don't want to wait the next file rotation.
432 */
434 }
435
437 {
438 /* Do a logfile rotation if it's time */
439 now = (pg_time_t) time(NULL);
440 if (now >= next_rotation_time)
441 rotation_requested = time_based_rotation = true;
442 }
443
445 {
446 /* Do a rotation if file is too big */
447 if (ftello(syslogFile) >= Log_RotationSize * (pgoff_t) 1024)
448 {
449 rotation_requested = true;
450 size_rotation_for |= LOG_DESTINATION_STDERR;
451 }
452 if (csvlogFile != NULL &&
454 {
455 rotation_requested = true;
456 size_rotation_for |= LOG_DESTINATION_CSVLOG;
457 }
458 if (jsonlogFile != NULL &&
460 {
461 rotation_requested = true;
462 size_rotation_for |= LOG_DESTINATION_JSONLOG;
463 }
464 }
465
467 {
468 /*
469 * Force rotation when both values are zero. It means the request
470 * was sent by pg_rotate_logfile() or "pg_ctl logrotate".
471 */
472 if (!time_based_rotation && size_rotation_for == 0)
473 size_rotation_for = LOG_DESTINATION_STDERR |
476 logfile_rotate(time_based_rotation, size_rotation_for);
477 }
478
479 /*
480 * Calculate time till next time-based rotation, so that we don't
481 * sleep longer than that. We assume the value of "now" obtained
482 * above is still close enough. Note we can't make this calculation
483 * until after calling logfile_rotate(), since it will advance
484 * next_rotation_time.
485 *
486 * Also note that we need to beware of overflow in calculation of the
487 * timeout: with large settings of Log_RotationAge, next_rotation_time
488 * could be more than INT_MAX msec in the future. In that case we'll
489 * wait no more than INT_MAX msec, and try again.
490 */
492 {
493 pg_time_t delay;
494
495 delay = next_rotation_time - now;
496 if (delay > 0)
497 {
498 if (delay > INT_MAX / 1000)
499 delay = INT_MAX / 1000;
500 cur_timeout = delay * 1000L; /* msec */
501 }
502 else
503 cur_timeout = 0;
504 }
505 else
506 cur_timeout = -1L;
507
508 /*
509 * Sleep until there's something to do
510 */
511#ifndef WIN32
512 rc = WaitEventSetWait(wes, cur_timeout, &event, 1,
513 WAIT_EVENT_SYSLOGGER_MAIN);
514
515 if (rc == 1 && event.events == WL_SOCKET_READABLE)
516 {
517 int bytesRead;
518
519 bytesRead = read(syslogPipe[0],
520 logbuffer + bytes_in_logbuffer,
521 sizeof(logbuffer) - bytes_in_logbuffer);
522 if (bytesRead < 0)
523 {
524 if (errno != EINTR)
525 ereport(LOG,
527 errmsg("could not read from logger pipe: %m")));
528 }
529 else if (bytesRead > 0)
530 {
531 bytes_in_logbuffer += bytesRead;
532 process_pipe_input(logbuffer, &bytes_in_logbuffer);
533 continue;
534 }
535 else
536 {
537 /*
538 * Zero bytes read when select() is saying read-ready means
539 * EOF on the pipe: that is, there are no longer any processes
540 * with the pipe write end open. Therefore, the postmaster
541 * and all backends are shut down, and we are done.
542 */
543 pipe_eof_seen = true;
544
545 /* if there's any data left then force it out now */
546 flush_pipe_input(logbuffer, &bytes_in_logbuffer);
547 }
548 }
549#else /* WIN32 */
550
551 /*
552 * On Windows we leave it to a separate thread to transfer data and
553 * detect pipe EOF. The main thread just wakes up to handle SIGHUP
554 * and rotation conditions.
555 *
556 * Server code isn't generally thread-safe, so we ensure that only one
557 * of the threads is active at a time by entering the critical section
558 * whenever we're not sleeping.
559 */
560 LeaveCriticalSection(&sysloggerSection);
561
562 (void) WaitEventSetWait(wes, cur_timeout, &event, 1,
563 WAIT_EVENT_SYSLOGGER_MAIN);
564
565 EnterCriticalSection(&sysloggerSection);
566#endif /* WIN32 */
567
568 if (pipe_eof_seen)
569 {
570 /*
571 * seeing this message on the real stderr is annoying - so we make
572 * it DEBUG1 to suppress in normal use.
573 */
575 (errmsg_internal("logger shutting down")));
576
577 /*
578 * Normal exit from the syslogger is here. Note that we
579 * deliberately do not close syslogFile before exiting; this is to
580 * allow for the possibility of elog messages being generated
581 * inside proc_exit. Regular exit() will take care of flushing
582 * and closing stdio channels.
583 */
584 proc_exit(0);
585 }
586 }
587}
sigset_t UnBlockSig
Definition: pqsignal.c:22
Datum now(PG_FUNCTION_ARGS)
Definition: timestamp.c:1608
@ DestNone
Definition: dest.h:87
int errmsg_internal(const char *fmt,...)
Definition: elog.c:1157
#define DEBUG1
Definition: elog.h:30
#define elog(elevel,...)
Definition: elog.h:225
#define LOG_DESTINATION_STDERR
Definition: elog.h:484
pg_time_t MyStartTime
Definition: globals.c:47
struct Latch * MyLatch
Definition: globals.c:62
void ProcessConfigFile(GucContext context)
Definition: guc-file.l:120
@ PGC_SIGHUP
Definition: guc.h:75
#define read(a, b, c)
Definition: win32.h:13
volatile sig_atomic_t ConfigReloadPending
Definition: interrupt.c:27
void SignalHandlerForConfigReload(SIGNAL_ARGS)
Definition: interrupt.c:61
void proc_exit(int code)
Definition: ipc.c:104
void ResetLatch(Latch *latch)
Definition: latch.c:372
char * pstrdup(const char *in)
Definition: mcxt.c:1699
MemoryContext PostmasterContext
Definition: mcxt.c:151
void MemoryContextDelete(MemoryContext context)
Definition: mcxt.c:454
BackendType MyBackendType
Definition: miscinit.c:64
int64 pg_time_t
Definition: pgtime.h:23
#define pqsignal
Definition: port.h:521
#define DEVNULL
Definition: port.h:161
#define PGINVALID_SOCKET
Definition: port.h:31
#define pgoff_t
Definition: port.h:401
CommandDest whereToSendOutput
Definition: postgres.c:91
void init_ps_display(const char *fixed_part)
Definition: ps_status.c:269
uint32 events
Definition: waiteventset.h:62
static bool rotation_disabled
Definition: syslogger.c:83
static void logfile_rotate(bool time_based_rotation, int size_rotation_for)
Definition: syslogger.c:1363
static bool pipe_eof_seen
Definition: syslogger.c:82
#define READ_BUF_SIZE
Definition: syslogger.c:60
static void update_metainfo_datafile(void)
Definition: syslogger.c:1477
static char * last_csv_file_name
Definition: syslogger.c:89
int Log_RotationAge
Definition: syslogger.c:71
static void process_pipe_input(char *logbuffer, int *bytes_in_logbuffer)
Definition: syslogger.c:879
char * Log_filename
Definition: syslogger.c:74
static pg_time_t next_rotation_time
Definition: syslogger.c:81
static volatile sig_atomic_t rotation_requested
Definition: syslogger.c:127
int Log_RotationSize
Definition: syslogger.c:72
static void sigUsr1Handler(SIGNAL_ARGS)
Definition: syslogger.c:1595
static void set_next_rotation_time(void)
Definition: syslogger.c:1442
static void flush_pipe_input(char *logbuffer, int *bytes_in_logbuffer)
Definition: syslogger.c:1042
static char * last_json_file_name
Definition: syslogger.c:90
static char * last_sys_file_name
Definition: syslogger.c:88
int AddWaitEventToSet(WaitEventSet *set, uint32 events, pgsocket fd, Latch *latch, void *user_data)
Definition: waiteventset.c:569
int WaitEventSetWait(WaitEventSet *set, long timeout, WaitEvent *occurred_events, int nevents, uint32 wait_event_info)
WaitEventSet * CreateWaitEventSet(ResourceOwner resowner, int nevents)
Definition: waiteventset.c:363
#define WL_SOCKET_READABLE
Definition: waiteventset.h:35
#define WL_LATCH_SET
Definition: waiteventset.h:34
#define SIGCHLD
Definition: win32_port.h:168
#define SIGHUP
Definition: win32_port.h:158
#define EINTR
Definition: win32_port.h:364
#define SIGPIPE
Definition: win32_port.h:163
#define SIGQUIT
Definition: win32_port.h:159
#define ftello(stream)
Definition: win32_port.h:209
#define SIGUSR1
Definition: win32_port.h:170
#define SIGALRM
Definition: win32_port.h:164
#define SIGUSR2
Definition: win32_port.h:171

References AddWaitEventToSet(), Assert(), B_LOGGER, close, ConfigReloadPending, CreateWaitEventSet(), csvlogFile, SysloggerStartupData::csvlogFile, DEBUG1, DestNone, DEVNULL, EINTR, elog, ereport, errcode_for_socket_access(), errmsg(), errmsg_internal(), WaitEvent::events, FATAL, fd(), first_syslogger_file_time, flush_pipe_input(), ftello, init_ps_display(), jsonlogFile, SysloggerStartupData::jsonlogFile, last_csv_file_name, last_json_file_name, last_sys_file_name, LOG, Log_destination, LOG_DESTINATION_CSVLOG, LOG_DESTINATION_JSONLOG, LOG_DESTINATION_STDERR, Log_directory, Log_filename, Log_RotationAge, Log_RotationSize, logfile_getname(), logfile_rotate(), MakePGDirectory(), MemoryContextDelete(), MyBackendType, MyLatch, MyStartTime, next_rotation_time, now(), pfree(), PGC_SIGHUP, PGINVALID_SOCKET, pgoff_t, pipe_eof_seen, PostmasterContext, pqsignal, proc_exit(), process_pipe_input(), ProcessConfigFile(), pstrdup(), read, READ_BUF_SIZE, redirection_done, ResetLatch(), rotation_disabled, rotation_requested, set_next_rotation_time(), SIGALRM, SIGCHLD, SIGHUP, SignalHandlerForConfigReload(), SIGPIPE, SIGQUIT, SIGUSR1, sigUsr1Handler(), SIGUSR2, STDERR_FILENO, STDOUT_FILENO, syslogFile, SysloggerStartupData::syslogFile, syslogPipe, UnBlockSig, update_metainfo_datafile(), WaitEventSetWait(), whereToSendOutput, WL_LATCH_SET, and WL_SOCKET_READABLE.

◆ write_syslogger_file()

void write_syslogger_file ( const char *  buffer,
int  count,
int  destination 
)

Definition at line 1093 of file syslogger.c.

1094{
1095 int rc;
1096 FILE *logfile;
1097
1098 /*
1099 * If we're told to write to a structured log file, but it's not open,
1100 * dump the data to syslogFile (which is always open) instead. This can
1101 * happen if structured output is enabled after postmaster start and we've
1102 * been unable to open logFile. There are also race conditions during a
1103 * parameter change whereby backends might send us structured output
1104 * before we open the logFile or after we close it. Writing formatted
1105 * output to the regular log file isn't great, but it beats dropping log
1106 * output on the floor.
1107 *
1108 * Think not to improve this by trying to open logFile on-the-fly. Any
1109 * failure in that would lead to recursion.
1110 */
1111 if ((destination & LOG_DESTINATION_CSVLOG) && csvlogFile != NULL)
1113 else if ((destination & LOG_DESTINATION_JSONLOG) && jsonlogFile != NULL)
1115 else
1117
1118 rc = fwrite(buffer, 1, count, logfile);
1119
1120 /*
1121 * Try to report any failure. We mustn't use ereport because it would
1122 * just recurse right back here, but write_stderr is OK: it will write
1123 * either to the postmaster's original stderr, or to /dev/null, but never
1124 * to our input pipe which would result in a different sort of looping.
1125 */
1126 if (rc != count)
1127 write_stderr("could not write to log file: %m\n");
1128}
#define write_stderr(str)
Definition: parallel.c:186
static FILE * logfile
Definition: pg_regress.c:126

References csvlogFile, jsonlogFile, LOG_DESTINATION_CSVLOG, LOG_DESTINATION_JSONLOG, logfile, syslogFile, and write_stderr.

Referenced by flush_pipe_input(), process_pipe_input(), send_message_to_server_log(), write_csvlog(), and write_jsonlog().

Variable Documentation

◆ Log_directory

PGDLLIMPORT char* Log_directory
extern

◆ Log_file_mode

PGDLLIMPORT int Log_file_mode
extern

Definition at line 76 of file syslogger.c.

Referenced by logfile_open(), and show_log_file_mode().

◆ Log_filename

PGDLLIMPORT char* Log_filename
extern

Definition at line 74 of file syslogger.c.

Referenced by logfile_getname(), and SysLoggerMain().

◆ Log_RotationAge

PGDLLIMPORT int Log_RotationAge
extern

Definition at line 71 of file syslogger.c.

Referenced by set_next_rotation_time(), and SysLoggerMain().

◆ Log_RotationSize

PGDLLIMPORT int Log_RotationSize
extern

Definition at line 72 of file syslogger.c.

Referenced by SysLoggerMain().

◆ Log_truncate_on_rotation

PGDLLIMPORT bool Log_truncate_on_rotation
extern

Definition at line 75 of file syslogger.c.

Referenced by logfile_rotate_dest().

◆ Logging_collector

PGDLLIMPORT bool Logging_collector
extern

◆ syslogPipe

PGDLLIMPORT int syslogPipe[2]
extern

Definition at line 114 of file syslogger.c.

Referenced by ClosePostmasterPorts(), SysLogger_Start(), and SysLoggerMain().