From 4641f8535c2be4b75285ac34d87e883bec250e48 Mon Sep 17 00:00:00 2001 From: Michael Paquier Date: Tue, 28 Sep 2021 11:48:18 +0900 Subject: [PATCH v4 1/5] Refactor per-destination file rotation in syslogger --- src/backend/postmaster/syslogger.c | 242 ++++++++++++++--------------- 1 file changed, 119 insertions(+), 123 deletions(-) diff --git a/src/backend/postmaster/syslogger.c b/src/backend/postmaster/syslogger.c index c5f9c5202d..4a019db7f4 100644 --- a/src/backend/postmaster/syslogger.c +++ b/src/backend/postmaster/syslogger.c @@ -87,7 +87,7 @@ static bool rotation_disabled = false; static FILE *syslogFile = NULL; static FILE *csvlogFile = NULL; NON_EXEC_STATIC pg_time_t first_syslogger_file_time = 0; -static char *last_file_name = NULL; +static char *last_sys_file_name = NULL; static char *last_csv_file_name = NULL; /* @@ -274,7 +274,7 @@ SysLoggerMain(int argc, char *argv[]) * 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_file_name = logfile_getname(first_syslogger_file_time, NULL); + 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"); @@ -1241,16 +1241,118 @@ logfile_open(const char *filename, const char *mode, bool allow_errors) 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, and 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; + 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 + * LOG_DESTINATION_STDERR is disabled. + */ + 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. + */ + 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 + { + /* 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) { - char *filename; - char *csvfilename = NULL; pg_time_t fntime; - FILE *fh; rotation_requested = false; @@ -1263,124 +1365,18 @@ logfile_rotate(bool time_based_rotation, int size_rotation_for) fntime = next_rotation_time; else fntime = time(NULL); - filename = logfile_getname(fntime, NULL); - if (Log_destination & LOG_DESTINATION_CSVLOG) - csvfilename = logfile_getname(fntime, ".csv"); - /* - * 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. - * - * Note: last_file_name should never be NULL here, but if it is, append. - */ - if (time_based_rotation || (size_rotation_for & LOG_DESTINATION_STDERR)) - { - 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); + /* file rotation for stderr */ + if (!logfile_rotate_dest(time_based_rotation, size_rotation_for, fntime, + LOG_DESTINATION_STDERR, &last_sys_file_name, + &syslogFile)) + return; - 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); - if (csvfilename) - pfree(csvfilename); - return; - } - - fclose(syslogFile); - syslogFile = fh; - - /* instead of pfree'ing filename, remember it for next time */ - if (last_file_name != NULL) - pfree(last_file_name); - last_file_name = filename; - filename = NULL; - } - - /* - * Same as above, but for csv file. Note that if LOG_DESTINATION_CSVLOG - * was just turned on, we might have to open csvlogFile here though it was - * not open before. In such a case we'll append not overwrite (since - * last_csv_file_name will be NULL); that is consistent with the normal - * rules since it's not a time-based rotation. - */ - if ((Log_destination & LOG_DESTINATION_CSVLOG) && - (csvlogFile == NULL || - time_based_rotation || (size_rotation_for & LOG_DESTINATION_CSVLOG))) - { - if (Log_truncate_on_rotation && time_based_rotation && - last_csv_file_name != NULL && - strcmp(csvfilename, last_csv_file_name) != 0) - fh = logfile_open(csvfilename, "w", true); - else - fh = logfile_open(csvfilename, "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); - if (csvfilename) - pfree(csvfilename); - return; - } - - if (csvlogFile != NULL) - fclose(csvlogFile); - csvlogFile = fh; - - /* instead of pfree'ing filename, remember it for next time */ - if (last_csv_file_name != NULL) - pfree(last_csv_file_name); - last_csv_file_name = csvfilename; - csvfilename = NULL; - } - else if (!(Log_destination & LOG_DESTINATION_CSVLOG) && - csvlogFile != NULL) - { - /* CSVLOG was just turned off, so close the old file */ - fclose(csvlogFile); - csvlogFile = NULL; - if (last_csv_file_name != NULL) - pfree(last_csv_file_name); - last_csv_file_name = NULL; - } - - if (filename) - pfree(filename); - if (csvfilename) - pfree(csvfilename); + /* file rotation for csvlog */ + if (!logfile_rotate_dest(time_based_rotation, size_rotation_for, fntime, + LOG_DESTINATION_CSVLOG, &last_csv_file_name, + &csvlogFile)) + return; update_metainfo_datafile(); @@ -1501,9 +1497,9 @@ update_metainfo_datafile(void) return; } - if (last_file_name && (Log_destination & LOG_DESTINATION_STDERR)) + if (last_sys_file_name && (Log_destination & LOG_DESTINATION_STDERR)) { - if (fprintf(fh, "stderr %s\n", last_file_name) < 0) + if (fprintf(fh, "stderr %s\n", last_sys_file_name) < 0) { ereport(LOG, (errcode_for_file_access(), -- 2.33.0