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-rw-r--r--src/backend/postmaster/syslogger.c1651
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diff --git a/src/backend/postmaster/syslogger.c b/src/backend/postmaster/syslogger.c
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+/*-------------------------------------------------------------------------
+ *
+ * syslogger.c
+ *
+ * The system logger (syslogger) appeared in Postgres 8.0. It catches all
+ * stderr output from the postmaster, backends, and other subprocesses
+ * by redirecting to a pipe, and writes it to a set of logfiles.
+ * It's possible to have size and age limits for the logfile configured
+ * in postgresql.conf. If these limits are reached or passed, the
+ * current logfile is closed and a new one is created (rotated).
+ * The logfiles are stored in a subdirectory (configurable in
+ * postgresql.conf), using a user-selectable naming scheme.
+ *
+ * Author: Andreas Pflug <pgadmin@pse-consulting.de>
+ *
+ * Copyright (c) 2004-2023, PostgreSQL Global Development Group
+ *
+ *
+ * IDENTIFICATION
+ * src/backend/postmaster/syslogger.c
+ *
+ *-------------------------------------------------------------------------
+ */
+#include "postgres.h"
+
+#include <fcntl.h>
+#include <limits.h>
+#include <signal.h>
+#include <time.h>
+#include <unistd.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+
+#include "common/file_perm.h"
+#include "lib/stringinfo.h"
+#include "libpq/pqsignal.h"
+#include "miscadmin.h"
+#include "nodes/pg_list.h"
+#include "pgstat.h"
+#include "pgtime.h"
+#include "port/pg_bitutils.h"
+#include "postmaster/fork_process.h"
+#include "postmaster/interrupt.h"
+#include "postmaster/postmaster.h"
+#include "postmaster/syslogger.h"
+#include "storage/dsm.h"
+#include "storage/fd.h"
+#include "storage/ipc.h"
+#include "storage/latch.h"
+#include "storage/pg_shmem.h"
+#include "tcop/tcopprot.h"
+#include "utils/guc.h"
+#include "utils/ps_status.h"
+#include "utils/timestamp.h"
+
+/*
+ * We read() into a temp buffer twice as big as a chunk, so that any fragment
+ * left after processing can be moved down to the front and we'll still have
+ * room to read a full chunk.
+ */
+#define READ_BUF_SIZE (2 * PIPE_CHUNK_SIZE)
+
+/* Log rotation signal file path, relative to $PGDATA */
+#define LOGROTATE_SIGNAL_FILE "logrotate"
+
+
+/*
+ * GUC parameters. Logging_collector cannot be changed after postmaster
+ * start, but the rest can change at SIGHUP.
+ */
+bool Logging_collector = false;
+int Log_RotationAge = HOURS_PER_DAY * MINS_PER_HOUR;
+int Log_RotationSize = 10 * 1024;
+char *Log_directory = NULL;
+char *Log_filename = NULL;
+bool Log_truncate_on_rotation = false;
+int Log_file_mode = S_IRUSR | S_IWUSR;
+
+extern bool redirection_done;
+
+/*
+ * Private state
+ */
+static pg_time_t next_rotation_time;
+static bool pipe_eof_seen = false;
+static bool rotation_disabled = false;
+static FILE *syslogFile = NULL;
+static FILE *csvlogFile = NULL;
+static FILE *jsonlogFile = NULL;
+NON_EXEC_STATIC pg_time_t first_syslogger_file_time = 0;
+static char *last_sys_file_name = NULL;
+static char *last_csv_file_name = NULL;
+static char *last_json_file_name = NULL;
+
+/*
+ * Buffers for saving partial messages from different backends.
+ *
+ * Keep NBUFFER_LISTS lists of these, with the entry for a given source pid
+ * being in the list numbered (pid % NBUFFER_LISTS), so as to cut down on
+ * the number of entries we have to examine for any one incoming message.
+ * There must never be more than one entry for the same source pid.
+ *
+ * An inactive buffer is not removed from its list, just held for re-use.
+ * An inactive buffer has pid == 0 and undefined contents of data.
+ */
+typedef struct
+{
+ int32 pid; /* PID of source process */
+ StringInfoData data; /* accumulated data, as a StringInfo */
+} save_buffer;
+
+#define NBUFFER_LISTS 256
+static List *buffer_lists[NBUFFER_LISTS];
+
+/* These must be exported for EXEC_BACKEND case ... annoying */
+#ifndef WIN32
+int syslogPipe[2] = {-1, -1};
+#else
+HANDLE syslogPipe[2] = {0, 0};
+#endif
+
+#ifdef WIN32
+static HANDLE threadHandle = 0;
+static CRITICAL_SECTION sysloggerSection;
+#endif
+
+/*
+ * Flags set by interrupt handlers for later service in the main loop.
+ */
+static volatile sig_atomic_t rotation_requested = false;
+
+
+/* Local subroutines */
+#ifdef EXEC_BACKEND
+static int syslogger_fdget(FILE *file);
+static FILE *syslogger_fdopen(int fd);
+static pid_t syslogger_forkexec(void);
+static void syslogger_parseArgs(int argc, char *argv[]);
+#endif
+NON_EXEC_STATIC void SysLoggerMain(int argc, char *argv[]) pg_attribute_noreturn();
+static void process_pipe_input(char *logbuffer, int *bytes_in_logbuffer);
+static void flush_pipe_input(char *logbuffer, int *bytes_in_logbuffer);
+static FILE *logfile_open(const char *filename, const char *mode,
+ bool allow_errors);
+
+#ifdef WIN32
+static unsigned int __stdcall pipeThread(void *arg);
+#endif
+static void logfile_rotate(bool time_based_rotation, int size_rotation_for);
+static bool logfile_rotate_dest(bool time_based_rotation,
+ int size_rotation_for, pg_time_t fntime,
+ int target_dest, char **last_file_name,
+ FILE **logFile);
+static char *logfile_getname(pg_time_t timestamp, const char *suffix);
+static void set_next_rotation_time(void);
+static void sigUsr1Handler(SIGNAL_ARGS);
+static void update_metainfo_datafile(void);
+
+
+/*
+ * Main entry point for syslogger process
+ * argc/argv parameters are valid only in EXEC_BACKEND case.
+ */
+NON_EXEC_STATIC void
+SysLoggerMain(int argc, char *argv[])
+{
+#ifndef WIN32
+ char logbuffer[READ_BUF_SIZE];
+ int bytes_in_logbuffer = 0;
+#endif
+ char *currentLogDir;
+ char *currentLogFilename;
+ int currentLogRotationAge;
+ pg_time_t now;
+ WaitEventSet *wes;
+
+ now = MyStartTime;
+
+#ifdef EXEC_BACKEND
+ syslogger_parseArgs(argc, argv);
+#endif /* EXEC_BACKEND */
+
+ MyBackendType = B_LOGGER;
+ init_ps_display(NULL);
+
+ /*
+ * If we restarted, our stderr is already redirected into our own input
+ * pipe. This is of course pretty useless, not to mention that it
+ * interferes with detecting pipe EOF. Point stderr to /dev/null. This
+ * assumes that all interesting messages generated in the syslogger will
+ * come through elog.c and will be sent to write_syslogger_file.
+ */
+ if (redirection_done)
+ {
+ int fd = open(DEVNULL, O_WRONLY, 0);
+
+ /*
+ * The closes might look redundant, but they are not: we want to be
+ * darn sure the pipe gets closed even if the open failed. We can
+ * survive running with stderr pointing nowhere, but we can't afford
+ * to have extra pipe input descriptors hanging around.
+ *
+ * As we're just trying to reset these to go to DEVNULL, there's not
+ * much point in checking for failure from the close/dup2 calls here,
+ * if they fail then presumably the file descriptors are closed and
+ * any writes will go into the bitbucket anyway.
+ */
+ close(STDOUT_FILENO);
+ close(STDERR_FILENO);
+ if (fd != -1)
+ {
+ (void) dup2(fd, STDOUT_FILENO);
+ (void) dup2(fd, STDERR_FILENO);
+ close(fd);
+ }
+ }
+
+ /*
+ * Syslogger's own stderr can't be the syslogPipe, so set it back to text
+ * mode if we didn't just close it. (It was set to binary in
+ * SubPostmasterMain).
+ */
+#ifdef WIN32
+ else
+ _setmode(STDERR_FILENO, _O_TEXT);
+#endif
+
+ /*
+ * Also close our copy of the write end of the pipe. This is needed to
+ * ensure we can detect pipe EOF correctly. (But note that in the restart
+ * case, the postmaster already did this.)
+ */
+#ifndef WIN32
+ if (syslogPipe[1] >= 0)
+ close(syslogPipe[1]);
+ syslogPipe[1] = -1;
+#else
+ if (syslogPipe[1])
+ CloseHandle(syslogPipe[1]);
+ syslogPipe[1] = 0;
+#endif
+
+ /*
+ * Properly accept or ignore signals the postmaster might send us
+ *
+ * Note: we ignore all termination signals, and instead exit only when all
+ * upstream processes are gone, to ensure we don't miss any dying gasps of
+ * broken backends...
+ */
+
+ pqsignal(SIGHUP, SignalHandlerForConfigReload); /* set flag to read config
+ * file */
+ pqsignal(SIGINT, SIG_IGN);
+ pqsignal(SIGTERM, SIG_IGN);
+ pqsignal(SIGQUIT, SIG_IGN);
+ pqsignal(SIGALRM, SIG_IGN);
+ pqsignal(SIGPIPE, SIG_IGN);
+ pqsignal(SIGUSR1, sigUsr1Handler); /* request log rotation */
+ pqsignal(SIGUSR2, SIG_IGN);
+
+ /*
+ * Reset some signals that are accepted by postmaster but not here
+ */
+ pqsignal(SIGCHLD, SIG_DFL);
+
+ sigprocmask(SIG_SETMASK, &UnBlockSig, NULL);
+
+#ifdef WIN32
+ /* Fire up separate data transfer thread */
+ InitializeCriticalSection(&sysloggerSection);
+ EnterCriticalSection(&sysloggerSection);
+
+ threadHandle = (HANDLE) _beginthreadex(NULL, 0, pipeThread, NULL, 0, NULL);
+ if (threadHandle == 0)
+ elog(FATAL, "could not create syslogger data transfer thread: %m");
+#endif /* WIN32 */
+
+ /*
+ * Remember active logfiles' name(s). We recompute 'em from the reference
+ * time because passing down just the pg_time_t is a lot cheaper than
+ * passing a whole file path in the EXEC_BACKEND case.
+ */
+ last_sys_file_name = logfile_getname(first_syslogger_file_time, NULL);
+ if (csvlogFile != NULL)
+ last_csv_file_name = logfile_getname(first_syslogger_file_time, ".csv");
+ if (jsonlogFile != NULL)
+ last_json_file_name = logfile_getname(first_syslogger_file_time, ".json");
+
+ /* remember active logfile parameters */
+ currentLogDir = pstrdup(Log_directory);
+ currentLogFilename = pstrdup(Log_filename);
+ currentLogRotationAge = Log_RotationAge;
+ /* set next planned rotation time */
+ set_next_rotation_time();
+ update_metainfo_datafile();
+
+ /*
+ * Reset whereToSendOutput, as the postmaster will do (but hasn't yet, at
+ * the point where we forked). This prevents duplicate output of messages
+ * from syslogger itself.
+ */
+ whereToSendOutput = DestNone;
+
+ /*
+ * Set up a reusable WaitEventSet object we'll use to wait for our latch,
+ * and (except on Windows) our socket.
+ *
+ * Unlike all other postmaster child processes, we'll ignore postmaster
+ * death because we want to collect final log output from all backends and
+ * then exit last. We'll do that by running until we see EOF on the
+ * syslog pipe, which implies that all other backends have exited
+ * (including the postmaster).
+ */
+ wes = CreateWaitEventSet(CurrentMemoryContext, 2);
+ AddWaitEventToSet(wes, WL_LATCH_SET, PGINVALID_SOCKET, MyLatch, NULL);
+#ifndef WIN32
+ AddWaitEventToSet(wes, WL_SOCKET_READABLE, syslogPipe[0], NULL, NULL);
+#endif
+
+ /* main worker loop */
+ for (;;)
+ {
+ bool time_based_rotation = false;
+ int size_rotation_for = 0;
+ long cur_timeout;
+ WaitEvent event;
+
+#ifndef WIN32
+ int rc;
+#endif
+
+ /* Clear any already-pending wakeups */
+ ResetLatch(MyLatch);
+
+ /*
+ * Process any requests or signals received recently.
+ */
+ if (ConfigReloadPending)
+ {
+ ConfigReloadPending = false;
+ ProcessConfigFile(PGC_SIGHUP);
+
+ /*
+ * Check if the log directory or filename pattern changed in
+ * postgresql.conf. If so, force rotation to make sure we're
+ * writing the logfiles in the right place.
+ */
+ if (strcmp(Log_directory, currentLogDir) != 0)
+ {
+ pfree(currentLogDir);
+ currentLogDir = pstrdup(Log_directory);
+ rotation_requested = true;
+
+ /*
+ * Also, create new directory if not present; ignore errors
+ */
+ (void) MakePGDirectory(Log_directory);
+ }
+ if (strcmp(Log_filename, currentLogFilename) != 0)
+ {
+ pfree(currentLogFilename);
+ currentLogFilename = pstrdup(Log_filename);
+ rotation_requested = true;
+ }
+
+ /*
+ * Force a rotation if CSVLOG output was just turned on or off and
+ * we need to open or close csvlogFile accordingly.
+ */
+ if (((Log_destination & LOG_DESTINATION_CSVLOG) != 0) !=
+ (csvlogFile != NULL))
+ rotation_requested = true;
+
+ /*
+ * Force a rotation if JSONLOG output was just turned on or off
+ * and we need to open or close jsonlogFile accordingly.
+ */
+ if (((Log_destination & LOG_DESTINATION_JSONLOG) != 0) !=
+ (jsonlogFile != NULL))
+ rotation_requested = true;
+
+ /*
+ * If rotation time parameter changed, reset next rotation time,
+ * but don't immediately force a rotation.
+ */
+ if (currentLogRotationAge != Log_RotationAge)
+ {
+ currentLogRotationAge = Log_RotationAge;
+ set_next_rotation_time();
+ }
+
+ /*
+ * If we had a rotation-disabling failure, re-enable rotation
+ * attempts after SIGHUP, and force one immediately.
+ */
+ if (rotation_disabled)
+ {
+ rotation_disabled = false;
+ rotation_requested = true;
+ }
+
+ /*
+ * Force rewriting last log filename when reloading configuration.
+ * Even if rotation_requested is false, log_destination may have
+ * been changed and we don't want to wait the next file rotation.
+ */
+ update_metainfo_datafile();
+ }
+
+ if (Log_RotationAge > 0 && !rotation_disabled)
+ {
+ /* Do a logfile rotation if it's time */
+ now = (pg_time_t) time(NULL);
+ if (now >= next_rotation_time)
+ rotation_requested = time_based_rotation = true;
+ }
+
+ if (!rotation_requested && Log_RotationSize > 0 && !rotation_disabled)
+ {
+ /* Do a rotation if file is too big */
+ if (ftell(syslogFile) >= Log_RotationSize * 1024L)
+ {
+ rotation_requested = true;
+ size_rotation_for |= LOG_DESTINATION_STDERR;
+ }
+ if (csvlogFile != NULL &&
+ ftell(csvlogFile) >= Log_RotationSize * 1024L)
+ {
+ rotation_requested = true;
+ size_rotation_for |= LOG_DESTINATION_CSVLOG;
+ }
+ if (jsonlogFile != NULL &&
+ ftell(jsonlogFile) >= Log_RotationSize * 1024L)
+ {
+ rotation_requested = true;
+ size_rotation_for |= LOG_DESTINATION_JSONLOG;
+ }
+ }
+
+ if (rotation_requested)
+ {
+ /*
+ * Force rotation when both values are zero. It means the request
+ * was sent by pg_rotate_logfile() or "pg_ctl logrotate".
+ */
+ if (!time_based_rotation && size_rotation_for == 0)
+ size_rotation_for = LOG_DESTINATION_STDERR |
+ LOG_DESTINATION_CSVLOG |
+ LOG_DESTINATION_JSONLOG;
+ logfile_rotate(time_based_rotation, size_rotation_for);
+ }
+
+ /*
+ * Calculate time till next time-based rotation, so that we don't
+ * sleep longer than that. We assume the value of "now" obtained
+ * above is still close enough. Note we can't make this calculation
+ * until after calling logfile_rotate(), since it will advance
+ * next_rotation_time.
+ *
+ * Also note that we need to beware of overflow in calculation of the
+ * timeout: with large settings of Log_RotationAge, next_rotation_time
+ * could be more than INT_MAX msec in the future. In that case we'll
+ * wait no more than INT_MAX msec, and try again.
+ */
+ if (Log_RotationAge > 0 && !rotation_disabled)
+ {
+ pg_time_t delay;
+
+ delay = next_rotation_time - now;
+ if (delay > 0)
+ {
+ if (delay > INT_MAX / 1000)
+ delay = INT_MAX / 1000;
+ cur_timeout = delay * 1000L; /* msec */
+ }
+ else
+ cur_timeout = 0;
+ }
+ else
+ cur_timeout = -1L;
+
+ /*
+ * Sleep until there's something to do
+ */
+#ifndef WIN32
+ rc = WaitEventSetWait(wes, cur_timeout, &event, 1,
+ WAIT_EVENT_SYSLOGGER_MAIN);
+
+ if (rc == 1 && event.events == WL_SOCKET_READABLE)
+ {
+ int bytesRead;
+
+ bytesRead = read(syslogPipe[0],
+ logbuffer + bytes_in_logbuffer,
+ sizeof(logbuffer) - bytes_in_logbuffer);
+ if (bytesRead < 0)
+ {
+ if (errno != EINTR)
+ ereport(LOG,
+ (errcode_for_socket_access(),
+ errmsg("could not read from logger pipe: %m")));
+ }
+ else if (bytesRead > 0)
+ {
+ bytes_in_logbuffer += bytesRead;
+ process_pipe_input(logbuffer, &bytes_in_logbuffer);
+ continue;
+ }
+ else
+ {
+ /*
+ * Zero bytes read when select() is saying read-ready means
+ * EOF on the pipe: that is, there are no longer any processes
+ * with the pipe write end open. Therefore, the postmaster
+ * and all backends are shut down, and we are done.
+ */
+ pipe_eof_seen = true;
+
+ /* if there's any data left then force it out now */
+ flush_pipe_input(logbuffer, &bytes_in_logbuffer);
+ }
+ }
+#else /* WIN32 */
+
+ /*
+ * On Windows we leave it to a separate thread to transfer data and
+ * detect pipe EOF. The main thread just wakes up to handle SIGHUP
+ * and rotation conditions.
+ *
+ * Server code isn't generally thread-safe, so we ensure that only one
+ * of the threads is active at a time by entering the critical section
+ * whenever we're not sleeping.
+ */
+ LeaveCriticalSection(&sysloggerSection);
+
+ (void) WaitEventSetWait(wes, cur_timeout, &event, 1,
+ WAIT_EVENT_SYSLOGGER_MAIN);
+
+ EnterCriticalSection(&sysloggerSection);
+#endif /* WIN32 */
+
+ if (pipe_eof_seen)
+ {
+ /*
+ * seeing this message on the real stderr is annoying - so we make
+ * it DEBUG1 to suppress in normal use.
+ */
+ ereport(DEBUG1,
+ (errmsg_internal("logger shutting down")));
+
+ /*
+ * Normal exit from the syslogger is here. Note that we
+ * deliberately do not close syslogFile before exiting; this is to
+ * allow for the possibility of elog messages being generated
+ * inside proc_exit. Regular exit() will take care of flushing
+ * and closing stdio channels.
+ */
+ proc_exit(0);
+ }
+ }
+}
+
+/*
+ * Postmaster subroutine to start a syslogger subprocess.
+ */
+int
+SysLogger_Start(void)
+{
+ pid_t sysloggerPid;
+ char *filename;
+
+ if (!Logging_collector)
+ return 0;
+
+ /*
+ * If first time through, create the pipe which will receive stderr
+ * output.
+ *
+ * If the syslogger crashes and needs to be restarted, we continue to use
+ * the same pipe (indeed must do so, since extant backends will be writing
+ * into that pipe).
+ *
+ * This means the postmaster must continue to hold the read end of the
+ * pipe open, so we can pass it down to the reincarnated syslogger. This
+ * is a bit klugy but we have little choice.
+ *
+ * Also note that we don't bother counting the pipe FDs by calling
+ * Reserve/ReleaseExternalFD. There's no real need to account for them
+ * accurately in the postmaster or syslogger process, and both ends of the
+ * pipe will wind up closed in all other postmaster children.
+ */
+#ifndef WIN32
+ if (syslogPipe[0] < 0)
+ {
+ if (pipe(syslogPipe) < 0)
+ ereport(FATAL,
+ (errcode_for_socket_access(),
+ errmsg("could not create pipe for syslog: %m")));
+ }
+#else
+ if (!syslogPipe[0])
+ {
+ SECURITY_ATTRIBUTES sa;
+
+ memset(&sa, 0, sizeof(SECURITY_ATTRIBUTES));
+ sa.nLength = sizeof(SECURITY_ATTRIBUTES);
+ sa.bInheritHandle = TRUE;
+
+ if (!CreatePipe(&syslogPipe[0], &syslogPipe[1], &sa, 32768))
+ ereport(FATAL,
+ (errcode_for_file_access(),
+ errmsg("could not create pipe for syslog: %m")));
+ }
+#endif
+
+ /*
+ * Create log directory if not present; ignore errors
+ */
+ (void) MakePGDirectory(Log_directory);
+
+ /*
+ * The initial logfile is created right in the postmaster, to verify that
+ * the Log_directory is writable. We save the reference time so that the
+ * syslogger child process can recompute this file name.
+ *
+ * It might look a bit strange to re-do this during a syslogger restart,
+ * but we must do so since the postmaster closed syslogFile after the
+ * previous fork (and remembering that old file wouldn't be right anyway).
+ * Note we always append here, we won't overwrite any existing file. This
+ * is consistent with the normal rules, because by definition this is not
+ * a time-based rotation.
+ */
+ first_syslogger_file_time = time(NULL);
+
+ filename = logfile_getname(first_syslogger_file_time, NULL);
+
+ syslogFile = logfile_open(filename, "a", false);
+
+ pfree(filename);
+
+ /*
+ * Likewise for the initial CSV log file, if that's enabled. (Note that
+ * we open syslogFile even when only CSV output is nominally enabled,
+ * since some code paths will write to syslogFile anyway.)
+ */
+ if (Log_destination & LOG_DESTINATION_CSVLOG)
+ {
+ filename = logfile_getname(first_syslogger_file_time, ".csv");
+
+ csvlogFile = logfile_open(filename, "a", false);
+
+ pfree(filename);
+ }
+
+ /*
+ * Likewise for the initial JSON log file, if that's enabled. (Note that
+ * we open syslogFile even when only JSON output is nominally enabled,
+ * since some code paths will write to syslogFile anyway.)
+ */
+ if (Log_destination & LOG_DESTINATION_JSONLOG)
+ {
+ filename = logfile_getname(first_syslogger_file_time, ".json");
+
+ jsonlogFile = logfile_open(filename, "a", false);
+
+ pfree(filename);
+ }
+
+#ifdef EXEC_BACKEND
+ switch ((sysloggerPid = syslogger_forkexec()))
+#else
+ switch ((sysloggerPid = fork_process()))
+#endif
+ {
+ case -1:
+ ereport(LOG,
+ (errmsg("could not fork system logger: %m")));
+ return 0;
+
+#ifndef EXEC_BACKEND
+ case 0:
+ /* in postmaster child ... */
+ InitPostmasterChild();
+
+ /* Close the postmaster's sockets */
+ ClosePostmasterPorts(true);
+
+ /* Drop our connection to postmaster's shared memory, as well */
+ dsm_detach_all();
+ PGSharedMemoryDetach();
+
+ /* do the work */
+ SysLoggerMain(0, NULL);
+ break;
+#endif
+
+ default:
+ /* success, in postmaster */
+
+ /* now we redirect stderr, if not done already */
+ if (!redirection_done)
+ {
+#ifdef WIN32
+ int fd;
+#endif
+
+ /*
+ * Leave a breadcrumb trail when redirecting, in case the user
+ * forgets that redirection is active and looks only at the
+ * original stderr target file.
+ */
+ ereport(LOG,
+ (errmsg("redirecting log output to logging collector process"),
+ errhint("Future log output will appear in directory \"%s\".",
+ Log_directory)));
+
+#ifndef WIN32
+ fflush(stdout);
+ if (dup2(syslogPipe[1], STDOUT_FILENO) < 0)
+ ereport(FATAL,
+ (errcode_for_file_access(),
+ errmsg("could not redirect stdout: %m")));
+ fflush(stderr);
+ if (dup2(syslogPipe[1], STDERR_FILENO) < 0)
+ ereport(FATAL,
+ (errcode_for_file_access(),
+ errmsg("could not redirect stderr: %m")));
+ /* Now we are done with the write end of the pipe. */
+ close(syslogPipe[1]);
+ syslogPipe[1] = -1;
+#else
+
+ /*
+ * open the pipe in binary mode and make sure stderr is binary
+ * after it's been dup'ed into, to avoid disturbing the pipe
+ * chunking protocol.
+ */
+ fflush(stderr);
+ fd = _open_osfhandle((intptr_t) syslogPipe[1],
+ _O_APPEND | _O_BINARY);
+ if (dup2(fd, STDERR_FILENO) < 0)
+ ereport(FATAL,
+ (errcode_for_file_access(),
+ errmsg("could not redirect stderr: %m")));
+ close(fd);
+ _setmode(STDERR_FILENO, _O_BINARY);
+
+ /*
+ * Now we are done with the write end of the pipe.
+ * CloseHandle() must not be called because the preceding
+ * close() closes the underlying handle.
+ */
+ syslogPipe[1] = 0;
+#endif
+ redirection_done = true;
+ }
+
+ /* postmaster will never write the file(s); close 'em */
+ fclose(syslogFile);
+ syslogFile = NULL;
+ if (csvlogFile != NULL)
+ {
+ fclose(csvlogFile);
+ csvlogFile = NULL;
+ }
+ if (jsonlogFile != NULL)
+ {
+ fclose(jsonlogFile);
+ jsonlogFile = NULL;
+ }
+ return (int) sysloggerPid;
+ }
+
+ /* we should never reach here */
+ return 0;
+}
+
+
+#ifdef EXEC_BACKEND
+
+/*
+ * syslogger_fdget() -
+ *
+ * Utility wrapper to grab the file descriptor of an opened error output
+ * file. Used when building the command to fork the logging collector.
+ */
+static int
+syslogger_fdget(FILE *file)
+{
+#ifndef WIN32
+ if (file != NULL)
+ return fileno(file);
+ else
+ return -1;
+#else
+ if (file != NULL)
+ return (int) _get_osfhandle(_fileno(file));
+ else
+ return 0;
+#endif /* WIN32 */
+}
+
+/*
+ * syslogger_fdopen() -
+ *
+ * Utility wrapper to re-open an error output file, using the given file
+ * descriptor. Used when parsing arguments in a forked logging collector.
+ */
+static FILE *
+syslogger_fdopen(int fd)
+{
+ FILE *file = NULL;
+
+#ifndef WIN32
+ if (fd != -1)
+ {
+ file = fdopen(fd, "a");
+ setvbuf(file, NULL, PG_IOLBF, 0);
+ }
+#else /* WIN32 */
+ if (fd != 0)
+ {
+ fd = _open_osfhandle(fd, _O_APPEND | _O_TEXT);
+ if (fd > 0)
+ {
+ file = fdopen(fd, "a");
+ setvbuf(file, NULL, PG_IOLBF, 0);
+ }
+ }
+#endif /* WIN32 */
+
+ return file;
+}
+
+/*
+ * syslogger_forkexec() -
+ *
+ * Format up the arglist for, then fork and exec, a syslogger process
+ */
+static pid_t
+syslogger_forkexec(void)
+{
+ char *av[10];
+ int ac = 0;
+ char filenobuf[32];
+ char csvfilenobuf[32];
+ char jsonfilenobuf[32];
+
+ av[ac++] = "postgres";
+ av[ac++] = "--forklog";
+ av[ac++] = NULL; /* filled in by postmaster_forkexec */
+
+ /* static variables (those not passed by write_backend_variables) */
+ snprintf(filenobuf, sizeof(filenobuf), "%d",
+ syslogger_fdget(syslogFile));
+ av[ac++] = filenobuf;
+ snprintf(csvfilenobuf, sizeof(csvfilenobuf), "%d",
+ syslogger_fdget(csvlogFile));
+ av[ac++] = csvfilenobuf;
+ snprintf(jsonfilenobuf, sizeof(jsonfilenobuf), "%d",
+ syslogger_fdget(jsonlogFile));
+ av[ac++] = jsonfilenobuf;
+
+ av[ac] = NULL;
+ Assert(ac < lengthof(av));
+
+ return postmaster_forkexec(ac, av);
+}
+
+/*
+ * syslogger_parseArgs() -
+ *
+ * Extract data from the arglist for exec'ed syslogger process
+ */
+static void
+syslogger_parseArgs(int argc, char *argv[])
+{
+ int fd;
+
+ Assert(argc == 6);
+ argv += 3;
+
+ /*
+ * Re-open the error output files that were opened by SysLogger_Start().
+ *
+ * We expect this will always succeed, which is too optimistic, but if it
+ * fails there's not a lot we can do to report the problem anyway. As
+ * coded, we'll just crash on a null pointer dereference after failure...
+ */
+ fd = atoi(*argv++);
+ syslogFile = syslogger_fdopen(fd);
+ fd = atoi(*argv++);
+ csvlogFile = syslogger_fdopen(fd);
+ fd = atoi(*argv++);
+ jsonlogFile = syslogger_fdopen(fd);
+}
+#endif /* EXEC_BACKEND */
+
+
+/* --------------------------------
+ * pipe protocol handling
+ * --------------------------------
+ */
+
+/*
+ * Process data received through the syslogger pipe.
+ *
+ * This routine interprets the log pipe protocol which sends log messages as
+ * (hopefully atomic) chunks - such chunks are detected and reassembled here.
+ *
+ * The protocol has a header that starts with two nul bytes, then has a 16 bit
+ * length, the pid of the sending process, and a flag to indicate if it is
+ * the last chunk in a message. Incomplete chunks are saved until we read some
+ * more, and non-final chunks are accumulated until we get the final chunk.
+ *
+ * All of this is to avoid 2 problems:
+ * . partial messages being written to logfiles (messes rotation), and
+ * . messages from different backends being interleaved (messages garbled).
+ *
+ * Any non-protocol messages are written out directly. These should only come
+ * from non-PostgreSQL sources, however (e.g. third party libraries writing to
+ * stderr).
+ *
+ * logbuffer is the data input buffer, and *bytes_in_logbuffer is the number
+ * of bytes present. On exit, any not-yet-eaten data is left-justified in
+ * logbuffer, and *bytes_in_logbuffer is updated.
+ */
+static void
+process_pipe_input(char *logbuffer, int *bytes_in_logbuffer)
+{
+ char *cursor = logbuffer;
+ int count = *bytes_in_logbuffer;
+ int dest = LOG_DESTINATION_STDERR;
+
+ /* While we have enough for a header, process data... */
+ while (count >= (int) (offsetof(PipeProtoHeader, data) + 1))
+ {
+ PipeProtoHeader p;
+ int chunklen;
+ bits8 dest_flags;
+
+ /* Do we have a valid header? */
+ memcpy(&p, cursor, offsetof(PipeProtoHeader, data));
+ dest_flags = p.flags & (PIPE_PROTO_DEST_STDERR |
+ PIPE_PROTO_DEST_CSVLOG |
+ PIPE_PROTO_DEST_JSONLOG);
+ if (p.nuls[0] == '\0' && p.nuls[1] == '\0' &&
+ p.len > 0 && p.len <= PIPE_MAX_PAYLOAD &&
+ p.pid != 0 &&
+ pg_popcount((char *) &dest_flags, 1) == 1)
+ {
+ List *buffer_list;
+ ListCell *cell;
+ save_buffer *existing_slot = NULL,
+ *free_slot = NULL;
+ StringInfo str;
+
+ chunklen = PIPE_HEADER_SIZE + p.len;
+
+ /* Fall out of loop if we don't have the whole chunk yet */
+ if (count < chunklen)
+ break;
+
+ if ((p.flags & PIPE_PROTO_DEST_STDERR) != 0)
+ dest = LOG_DESTINATION_STDERR;
+ else if ((p.flags & PIPE_PROTO_DEST_CSVLOG) != 0)
+ dest = LOG_DESTINATION_CSVLOG;
+ else if ((p.flags & PIPE_PROTO_DEST_JSONLOG) != 0)
+ dest = LOG_DESTINATION_JSONLOG;
+ else
+ {
+ /* this should never happen as of the header validation */
+ Assert(false);
+ }
+
+ /* Locate any existing buffer for this source pid */
+ buffer_list = buffer_lists[p.pid % NBUFFER_LISTS];
+ foreach(cell, buffer_list)
+ {
+ save_buffer *buf = (save_buffer *) lfirst(cell);
+
+ if (buf->pid == p.pid)
+ {
+ existing_slot = buf;
+ break;
+ }
+ if (buf->pid == 0 && free_slot == NULL)
+ free_slot = buf;
+ }
+
+ if ((p.flags & PIPE_PROTO_IS_LAST) == 0)
+ {
+ /*
+ * Save a complete non-final chunk in a per-pid buffer
+ */
+ if (existing_slot != NULL)
+ {
+ /* Add chunk to data from preceding chunks */
+ str = &(existing_slot->data);
+ appendBinaryStringInfo(str,
+ cursor + PIPE_HEADER_SIZE,
+ p.len);
+ }
+ else
+ {
+ /* First chunk of message, save in a new buffer */
+ if (free_slot == NULL)
+ {
+ /*
+ * Need a free slot, but there isn't one in the list,
+ * so create a new one and extend the list with it.
+ */
+ free_slot = palloc(sizeof(save_buffer));
+ buffer_list = lappend(buffer_list, free_slot);
+ buffer_lists[p.pid % NBUFFER_LISTS] = buffer_list;
+ }
+ free_slot->pid = p.pid;
+ str = &(free_slot->data);
+ initStringInfo(str);
+ appendBinaryStringInfo(str,
+ cursor + PIPE_HEADER_SIZE,
+ p.len);
+ }
+ }
+ else
+ {
+ /*
+ * Final chunk --- add it to anything saved for that pid, and
+ * either way write the whole thing out.
+ */
+ if (existing_slot != NULL)
+ {
+ str = &(existing_slot->data);
+ appendBinaryStringInfo(str,
+ cursor + PIPE_HEADER_SIZE,
+ p.len);
+ write_syslogger_file(str->data, str->len, dest);
+ /* Mark the buffer unused, and reclaim string storage */
+ existing_slot->pid = 0;
+ pfree(str->data);
+ }
+ else
+ {
+ /* The whole message was one chunk, evidently. */
+ write_syslogger_file(cursor + PIPE_HEADER_SIZE, p.len,
+ dest);
+ }
+ }
+
+ /* Finished processing this chunk */
+ cursor += chunklen;
+ count -= chunklen;
+ }
+ else
+ {
+ /* Process non-protocol data */
+
+ /*
+ * Look for the start of a protocol header. If found, dump data
+ * up to there and repeat the loop. Otherwise, dump it all and
+ * fall out of the loop. (Note: we want to dump it all if at all
+ * possible, so as to avoid dividing non-protocol messages across
+ * logfiles. We expect that in many scenarios, a non-protocol
+ * message will arrive all in one read(), and we want to respect
+ * the read() boundary if possible.)
+ */
+ for (chunklen = 1; chunklen < count; chunklen++)
+ {
+ if (cursor[chunklen] == '\0')
+ break;
+ }
+ /* fall back on the stderr log as the destination */
+ write_syslogger_file(cursor, chunklen, LOG_DESTINATION_STDERR);
+ cursor += chunklen;
+ count -= chunklen;
+ }
+ }
+
+ /* We don't have a full chunk, so left-align what remains in the buffer */
+ if (count > 0 && cursor != logbuffer)
+ memmove(logbuffer, cursor, count);
+ *bytes_in_logbuffer = count;
+}
+
+/*
+ * Force out any buffered data
+ *
+ * This is currently used only at syslogger shutdown, but could perhaps be
+ * useful at other times, so it is careful to leave things in a clean state.
+ */
+static void
+flush_pipe_input(char *logbuffer, int *bytes_in_logbuffer)
+{
+ int i;
+
+ /* Dump any incomplete protocol messages */
+ for (i = 0; i < NBUFFER_LISTS; i++)
+ {
+ List *list = buffer_lists[i];
+ ListCell *cell;
+
+ foreach(cell, list)
+ {
+ save_buffer *buf = (save_buffer *) lfirst(cell);
+
+ if (buf->pid != 0)
+ {
+ StringInfo str = &(buf->data);
+
+ write_syslogger_file(str->data, str->len,
+ LOG_DESTINATION_STDERR);
+ /* Mark the buffer unused, and reclaim string storage */
+ buf->pid = 0;
+ pfree(str->data);
+ }
+ }
+ }
+
+ /*
+ * Force out any remaining pipe data as-is; we don't bother trying to
+ * remove any protocol headers that may exist in it.
+ */
+ if (*bytes_in_logbuffer > 0)
+ write_syslogger_file(logbuffer, *bytes_in_logbuffer,
+ LOG_DESTINATION_STDERR);
+ *bytes_in_logbuffer = 0;
+}
+
+
+/* --------------------------------
+ * logfile routines
+ * --------------------------------
+ */
+
+/*
+ * Write text to the currently open logfile
+ *
+ * This is exported so that elog.c can call it when MyBackendType is B_LOGGER.
+ * This allows the syslogger process to record elog messages of its own,
+ * even though its stderr does not point at the syslog pipe.
+ */
+void
+write_syslogger_file(const char *buffer, int count, int destination)
+{
+ int rc;
+ FILE *logfile;
+
+ /*
+ * If we're told to write to a structured log file, but it's not open,
+ * dump the data to syslogFile (which is always open) instead. This can
+ * happen if structured output is enabled after postmaster start and we've
+ * been unable to open logFile. There are also race conditions during a
+ * parameter change whereby backends might send us structured output
+ * before we open the logFile or after we close it. Writing formatted
+ * output to the regular log file isn't great, but it beats dropping log
+ * output on the floor.
+ *
+ * Think not to improve this by trying to open logFile on-the-fly. Any
+ * failure in that would lead to recursion.
+ */
+ if ((destination & LOG_DESTINATION_CSVLOG) && csvlogFile != NULL)
+ logfile = csvlogFile;
+ else if ((destination & LOG_DESTINATION_JSONLOG) && jsonlogFile != NULL)
+ logfile = jsonlogFile;
+ else
+ logfile = syslogFile;
+
+ rc = fwrite(buffer, 1, count, logfile);
+
+ /*
+ * Try to report any failure. We mustn't use ereport because it would
+ * just recurse right back here, but write_stderr is OK: it will write
+ * either to the postmaster's original stderr, or to /dev/null, but never
+ * to our input pipe which would result in a different sort of looping.
+ */
+ if (rc != count)
+ write_stderr("could not write to log file: %s\n", strerror(errno));
+}
+
+#ifdef WIN32
+
+/*
+ * Worker thread to transfer data from the pipe to the current logfile.
+ *
+ * We need this because on Windows, WaitForMultipleObjects does not work on
+ * unnamed pipes: it always reports "signaled", so the blocking ReadFile won't
+ * allow for SIGHUP; and select is for sockets only.
+ */
+static unsigned int __stdcall
+pipeThread(void *arg)
+{
+ char logbuffer[READ_BUF_SIZE];
+ int bytes_in_logbuffer = 0;
+
+ for (;;)
+ {
+ DWORD bytesRead;
+ BOOL result;
+
+ result = ReadFile(syslogPipe[0],
+ logbuffer + bytes_in_logbuffer,
+ sizeof(logbuffer) - bytes_in_logbuffer,
+ &bytesRead, 0);
+
+ /*
+ * Enter critical section before doing anything that might touch
+ * global state shared by the main thread. Anything that uses
+ * palloc()/pfree() in particular are not safe outside the critical
+ * section.
+ */
+ EnterCriticalSection(&sysloggerSection);
+ if (!result)
+ {
+ DWORD error = GetLastError();
+
+ if (error == ERROR_HANDLE_EOF ||
+ error == ERROR_BROKEN_PIPE)
+ break;
+ _dosmaperr(error);
+ ereport(LOG,
+ (errcode_for_file_access(),
+ errmsg("could not read from logger pipe: %m")));
+ }
+ else if (bytesRead > 0)
+ {
+ bytes_in_logbuffer += bytesRead;
+ process_pipe_input(logbuffer, &bytes_in_logbuffer);
+ }
+
+ /*
+ * If we've filled the current logfile, nudge the main thread to do a
+ * log rotation.
+ */
+ if (Log_RotationSize > 0)
+ {
+ if (ftell(syslogFile) >= Log_RotationSize * 1024L ||
+ (csvlogFile != NULL && ftell(csvlogFile) >= Log_RotationSize * 1024L) ||
+ (jsonlogFile != NULL && ftell(jsonlogFile) >= Log_RotationSize * 1024L))
+ SetLatch(MyLatch);
+ }
+ LeaveCriticalSection(&sysloggerSection);
+ }
+
+ /* We exit the above loop only upon detecting pipe EOF */
+ pipe_eof_seen = true;
+
+ /* if there's any data left then force it out now */
+ flush_pipe_input(logbuffer, &bytes_in_logbuffer);
+
+ /* set the latch to waken the main thread, which will quit */
+ SetLatch(MyLatch);
+
+ LeaveCriticalSection(&sysloggerSection);
+ _endthread();
+ return 0;
+}
+#endif /* WIN32 */
+
+/*
+ * Open a new logfile with proper permissions and buffering options.
+ *
+ * If allow_errors is true, we just log any open failure and return NULL
+ * (with errno still correct for the fopen failure).
+ * Otherwise, errors are treated as fatal.
+ */
+static FILE *
+logfile_open(const char *filename, const char *mode, bool allow_errors)
+{
+ FILE *fh;
+ mode_t oumask;
+
+ /*
+ * Note we do not let Log_file_mode disable IWUSR, since we certainly want
+ * to be able to write the files ourselves.
+ */
+ oumask = umask((mode_t) ((~(Log_file_mode | S_IWUSR)) & (S_IRWXU | S_IRWXG | S_IRWXO)));
+ fh = fopen(filename, mode);
+ umask(oumask);
+
+ if (fh)
+ {
+ setvbuf(fh, NULL, PG_IOLBF, 0);
+
+#ifdef WIN32
+ /* use CRLF line endings on Windows */
+ _setmode(_fileno(fh), _O_TEXT);
+#endif
+ }
+ else
+ {
+ int save_errno = errno;
+
+ ereport(allow_errors ? LOG : FATAL,
+ (errcode_for_file_access(),
+ errmsg("could not open log file \"%s\": %m",
+ filename)));
+ errno = save_errno;
+ }
+
+ return fh;
+}
+
+/*
+ * Do logfile rotation for a single destination, as specified by target_dest.
+ * The information stored in *last_file_name and *logFile is updated on a
+ * successful file rotation.
+ *
+ * Returns false if the rotation has been stopped, or true to move on to
+ * the processing of other formats.
+ */
+static bool
+logfile_rotate_dest(bool time_based_rotation, int size_rotation_for,
+ pg_time_t fntime, int target_dest,
+ char **last_file_name, FILE **logFile)
+{
+ char *logFileExt = NULL;
+ char *filename;
+ FILE *fh;
+
+ /*
+ * If the target destination was just turned off, close the previous file
+ * and unregister its data. This cannot happen for stderr as syslogFile
+ * is assumed to be always opened even if stderr is disabled in
+ * log_destination.
+ */
+ if ((Log_destination & target_dest) == 0 &&
+ target_dest != LOG_DESTINATION_STDERR)
+ {
+ if (*logFile != NULL)
+ fclose(*logFile);
+ *logFile = NULL;
+ if (*last_file_name != NULL)
+ pfree(*last_file_name);
+ *last_file_name = NULL;
+ return true;
+ }
+
+ /*
+ * Leave if it is not time for a rotation or if the target destination has
+ * no need to do a rotation based on the size of its file.
+ */
+ if (!time_based_rotation && (size_rotation_for & target_dest) == 0)
+ return true;
+
+ /* file extension depends on the destination type */
+ if (target_dest == LOG_DESTINATION_STDERR)
+ logFileExt = NULL;
+ else if (target_dest == LOG_DESTINATION_CSVLOG)
+ logFileExt = ".csv";
+ else if (target_dest == LOG_DESTINATION_JSONLOG)
+ logFileExt = ".json";
+ else
+ {
+ /* cannot happen */
+ Assert(false);
+ }
+
+ /* build the new file name */
+ filename = logfile_getname(fntime, logFileExt);
+
+ /*
+ * Decide whether to overwrite or append. We can overwrite if (a)
+ * Log_truncate_on_rotation is set, (b) the rotation was triggered by
+ * elapsed time and not something else, and (c) the computed file name is
+ * different from what we were previously logging into.
+ */
+ if (Log_truncate_on_rotation && time_based_rotation &&
+ *last_file_name != NULL &&
+ strcmp(filename, *last_file_name) != 0)
+ fh = logfile_open(filename, "w", true);
+ else
+ fh = logfile_open(filename, "a", true);
+
+ if (!fh)
+ {
+ /*
+ * ENFILE/EMFILE are not too surprising on a busy system; just keep
+ * using the old file till we manage to get a new one. Otherwise,
+ * assume something's wrong with Log_directory and stop trying to
+ * create files.
+ */
+ if (errno != ENFILE && errno != EMFILE)
+ {
+ ereport(LOG,
+ (errmsg("disabling automatic rotation (use SIGHUP to re-enable)")));
+ rotation_disabled = true;
+ }
+
+ if (filename)
+ pfree(filename);
+ return false;
+ }
+
+ /* fill in the new information */
+ if (*logFile != NULL)
+ fclose(*logFile);
+ *logFile = fh;
+
+ /* instead of pfree'ing filename, remember it for next time */
+ if (*last_file_name != NULL)
+ pfree(*last_file_name);
+ *last_file_name = filename;
+
+ return true;
+}
+
+/*
+ * perform logfile rotation
+ */
+static void
+logfile_rotate(bool time_based_rotation, int size_rotation_for)
+{
+ pg_time_t fntime;
+
+ rotation_requested = false;
+
+ /*
+ * When doing a time-based rotation, invent the new logfile name based on
+ * the planned rotation time, not current time, to avoid "slippage" in the
+ * file name when we don't do the rotation immediately.
+ */
+ if (time_based_rotation)
+ fntime = next_rotation_time;
+ else
+ fntime = time(NULL);
+
+ /* file rotation for stderr */
+ if (!logfile_rotate_dest(time_based_rotation, size_rotation_for, fntime,
+ LOG_DESTINATION_STDERR, &last_sys_file_name,
+ &syslogFile))
+ return;
+
+ /* file rotation for csvlog */
+ if (!logfile_rotate_dest(time_based_rotation, size_rotation_for, fntime,
+ LOG_DESTINATION_CSVLOG, &last_csv_file_name,
+ &csvlogFile))
+ return;
+
+ /* file rotation for jsonlog */
+ if (!logfile_rotate_dest(time_based_rotation, size_rotation_for, fntime,
+ LOG_DESTINATION_JSONLOG, &last_json_file_name,
+ &jsonlogFile))
+ return;
+
+ update_metainfo_datafile();
+
+ set_next_rotation_time();
+}
+
+
+/*
+ * construct logfile name using timestamp information
+ *
+ * If suffix isn't NULL, append it to the name, replacing any ".log"
+ * that may be in the pattern.
+ *
+ * Result is palloc'd.
+ */
+static char *
+logfile_getname(pg_time_t timestamp, const char *suffix)
+{
+ char *filename;
+ int len;
+
+ filename = palloc(MAXPGPATH);
+
+ snprintf(filename, MAXPGPATH, "%s/", Log_directory);
+
+ len = strlen(filename);
+
+ /* treat Log_filename as a strftime pattern */
+ pg_strftime(filename + len, MAXPGPATH - len, Log_filename,
+ pg_localtime(&timestamp, log_timezone));
+
+ if (suffix != NULL)
+ {
+ len = strlen(filename);
+ if (len > 4 && (strcmp(filename + (len - 4), ".log") == 0))
+ len -= 4;
+ strlcpy(filename + len, suffix, MAXPGPATH - len);
+ }
+
+ return filename;
+}
+
+/*
+ * Determine the next planned rotation time, and store in next_rotation_time.
+ */
+static void
+set_next_rotation_time(void)
+{
+ pg_time_t now;
+ struct pg_tm *tm;
+ int rotinterval;
+
+ /* nothing to do if time-based rotation is disabled */
+ if (Log_RotationAge <= 0)
+ return;
+
+ /*
+ * The requirements here are to choose the next time > now that is a
+ * "multiple" of the log rotation interval. "Multiple" can be interpreted
+ * fairly loosely. In this version we align to log_timezone rather than
+ * GMT.
+ */
+ rotinterval = Log_RotationAge * SECS_PER_MINUTE; /* convert to seconds */
+ now = (pg_time_t) time(NULL);
+ tm = pg_localtime(&now, log_timezone);
+ now += tm->tm_gmtoff;
+ now -= now % rotinterval;
+ now += rotinterval;
+ now -= tm->tm_gmtoff;
+ next_rotation_time = now;
+}
+
+/*
+ * Store the name of the file(s) where the log collector, when enabled, writes
+ * log messages. Useful for finding the name(s) of the current log file(s)
+ * when there is time-based logfile rotation. Filenames are stored in a
+ * temporary file and which is renamed into the final destination for
+ * atomicity. The file is opened with the same permissions as what gets
+ * created in the data directory and has proper buffering options.
+ */
+static void
+update_metainfo_datafile(void)
+{
+ FILE *fh;
+ mode_t oumask;
+
+ if (!(Log_destination & LOG_DESTINATION_STDERR) &&
+ !(Log_destination & LOG_DESTINATION_CSVLOG) &&
+ !(Log_destination & LOG_DESTINATION_JSONLOG))
+ {
+ if (unlink(LOG_METAINFO_DATAFILE) < 0 && errno != ENOENT)
+ ereport(LOG,
+ (errcode_for_file_access(),
+ errmsg("could not remove file \"%s\": %m",
+ LOG_METAINFO_DATAFILE)));
+ return;
+ }
+
+ /* use the same permissions as the data directory for the new file */
+ oumask = umask(pg_mode_mask);
+ fh = fopen(LOG_METAINFO_DATAFILE_TMP, "w");
+ umask(oumask);
+
+ if (fh)
+ {
+ setvbuf(fh, NULL, PG_IOLBF, 0);
+
+#ifdef WIN32
+ /* use CRLF line endings on Windows */
+ _setmode(_fileno(fh), _O_TEXT);
+#endif
+ }
+ else
+ {
+ ereport(LOG,
+ (errcode_for_file_access(),
+ errmsg("could not open file \"%s\": %m",
+ LOG_METAINFO_DATAFILE_TMP)));
+ return;
+ }
+
+ if (last_sys_file_name && (Log_destination & LOG_DESTINATION_STDERR))
+ {
+ if (fprintf(fh, "stderr %s\n", last_sys_file_name) < 0)
+ {
+ ereport(LOG,
+ (errcode_for_file_access(),
+ errmsg("could not write file \"%s\": %m",
+ LOG_METAINFO_DATAFILE_TMP)));
+ fclose(fh);
+ return;
+ }
+ }
+
+ if (last_csv_file_name && (Log_destination & LOG_DESTINATION_CSVLOG))
+ {
+ if (fprintf(fh, "csvlog %s\n", last_csv_file_name) < 0)
+ {
+ ereport(LOG,
+ (errcode_for_file_access(),
+ errmsg("could not write file \"%s\": %m",
+ LOG_METAINFO_DATAFILE_TMP)));
+ fclose(fh);
+ return;
+ }
+ }
+
+ if (last_json_file_name && (Log_destination & LOG_DESTINATION_JSONLOG))
+ {
+ if (fprintf(fh, "jsonlog %s\n", last_json_file_name) < 0)
+ {
+ ereport(LOG,
+ (errcode_for_file_access(),
+ errmsg("could not write file \"%s\": %m",
+ LOG_METAINFO_DATAFILE_TMP)));
+ fclose(fh);
+ return;
+ }
+ }
+ fclose(fh);
+
+ if (rename(LOG_METAINFO_DATAFILE_TMP, LOG_METAINFO_DATAFILE) != 0)
+ ereport(LOG,
+ (errcode_for_file_access(),
+ errmsg("could not rename file \"%s\" to \"%s\": %m",
+ LOG_METAINFO_DATAFILE_TMP, LOG_METAINFO_DATAFILE)));
+}
+
+/* --------------------------------
+ * signal handler routines
+ * --------------------------------
+ */
+
+/*
+ * Check to see if a log rotation request has arrived. Should be
+ * called by postmaster after receiving SIGUSR1.
+ */
+bool
+CheckLogrotateSignal(void)
+{
+ struct stat stat_buf;
+
+ if (stat(LOGROTATE_SIGNAL_FILE, &stat_buf) == 0)
+ return true;
+
+ return false;
+}
+
+/*
+ * Remove the file signaling a log rotation request.
+ */
+void
+RemoveLogrotateSignalFiles(void)
+{
+ unlink(LOGROTATE_SIGNAL_FILE);
+}
+
+/* SIGUSR1: set flag to rotate logfile */
+static void
+sigUsr1Handler(SIGNAL_ARGS)
+{
+ int save_errno = errno;
+
+ rotation_requested = true;
+ SetLatch(MyLatch);
+
+ errno = save_errno;
+}