/
pg_cron.c
2351 lines (1994 loc) · 57.7 KB
/
pg_cron.c
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/*-------------------------------------------------------------------------
*
* src/pg_cron.c
*
* Implementation of the pg_cron task scheduler.
* Wording:
* - A job is a scheduling definition of a task
* - A task is what is actually executed within the database engine
*
* Copyright (c) 2016, Citus Data, Inc.
*
*-------------------------------------------------------------------------
*/
#include <sys/resource.h>
#include "postgres.h"
#include "fmgr.h"
/* these are always necessary for a bgworker */
#include "miscadmin.h"
#include "postmaster/bgworker.h"
#include "storage/ipc.h"
#include "storage/latch.h"
#include "storage/lwlock.h"
#include "storage/proc.h"
#include "storage/shm_mq.h"
#include "storage/shm_toc.h"
#include "storage/shmem.h"
/* these headers are used by this particular worker's code */
#define MAIN_PROGRAM
#include "cron.h"
#include "pg_cron.h"
#include "task_states.h"
#include "job_metadata.h"
#ifdef HAVE_POLL_H
#include <poll.h>
#elif defined(HAVE_SYS_POLL_H)
#include <sys/poll.h>
#endif
#include "sys/time.h"
#include "time.h"
#include "access/genam.h"
#include "access/heapam.h"
#include "access/htup_details.h"
#include "access/printtup.h"
#include "access/xact.h"
#include "access/xlog.h"
#include "catalog/pg_extension.h"
#include "catalog/indexing.h"
#include "catalog/namespace.h"
#include "commands/async.h"
#include "commands/dbcommands.h"
#include "commands/extension.h"
#include "commands/sequence.h"
#include "commands/trigger.h"
#if (PG_VERSION_NUM >= 160000)
#include "utils/guc_hooks.h"
#else
#include "commands/variable.h"
#endif
#include "lib/stringinfo.h"
#include "libpq-fe.h"
#include "libpq/pqmq.h"
#include "libpq/pqsignal.h"
#include "mb/pg_wchar.h"
#include "parser/analyze.h"
#include "pgstat.h"
#include "postmaster/postmaster.h"
#include "utils/builtins.h"
#include "utils/fmgroids.h"
#include "utils/inval.h"
#include "utils/lsyscache.h"
#include "utils/memutils.h"
#include "utils/portal.h"
#include "utils/ps_status.h"
#include "utils/rel.h"
#include "utils/snapmgr.h"
#include "utils/syscache.h"
#include "utils/timeout.h"
#include "utils/timestamp.h"
#if (PG_VERSION_NUM >= 100000)
#include "utils/varlena.h"
#endif
#include "tcop/pquery.h"
#include "tcop/utility.h"
#include "libpq/pqformat.h"
#include "utils/builtins.h"
PG_MODULE_MAGIC;
#ifndef MAXINT8LEN
#define MAXINT8LEN 20
#endif
/* Table-of-contents constants for our dynamic shared memory segment. */
#define PG_CRON_MAGIC 0x51028080
#define PG_CRON_KEY_DATABASE 0
#define PG_CRON_KEY_USERNAME 1
#define PG_CRON_KEY_COMMAND 2
#define PG_CRON_KEY_QUEUE 3
#define PG_CRON_NKEYS 4
/* ways in which the clock can change between main loop iterations */
typedef enum
{
CLOCK_JUMP_BACKWARD = 0,
CLOCK_PROGRESSED = 1,
CLOCK_JUMP_FORWARD = 2,
CLOCK_CHANGE = 3
} ClockProgress;
/* forward declarations */
void _PG_init(void);
void _PG_fini(void);
static void pg_cron_sigterm(SIGNAL_ARGS);
static void pg_cron_sighup(SIGNAL_ARGS);
PGDLLEXPORT void PgCronLauncherMain(Datum arg);
PGDLLEXPORT void CronBackgroundWorker(Datum arg);
static void StartAllPendingRuns(List *taskList, TimestampTz currentTime);
static void StartPendingRuns(CronTask *task, ClockProgress clockProgress,
TimestampTz lastMinute, TimestampTz currentTime);
static int MinutesPassed(TimestampTz startTime, TimestampTz stopTime);
static TimestampTz TimestampMinuteStart(TimestampTz time);
static TimestampTz TimestampMinuteEnd(TimestampTz time);
static bool ShouldRunTask(entry *schedule, TimestampTz currentMinute,
bool doWild, bool doNonWild);
static void WaitForCronTasks(List *taskList);
static void WaitForLatch(int timeoutMs);
static void PollForTasks(List *taskList);
static bool CanStartTask(CronTask *task);
static void ManageCronTasks(List *taskList, TimestampTz currentTime);
static void ManageCronTask(CronTask *task, TimestampTz currentTime);
static void ExecuteSqlString(const char *sql);
static void GetTaskFeedback(PGresult *result, CronTask *task);
static void ProcessBgwTaskFeedback(CronTask *task, bool running);
static bool jobCanceled(CronTask *task);
static bool jobStartupTimeout(CronTask *task, TimestampTz currentTime);
static char* pg_cron_cmdTuples(char *msg);
static void bgw_generate_returned_message(StringInfoData *display_msg, ErrorData edata);
/* global settings */
char *CronTableDatabaseName = "postgres";
static bool CronLogStatement = true;
static bool CronLogRun = true;
static bool CronReloadConfig = false;
/* flags set by signal handlers */
static volatile sig_atomic_t got_sigterm = false;
/* global variables */
static int CronTaskStartTimeout = 10000; /* maximum connection time */
static const int MaxWait = 1000; /* maximum time in ms that poll() can block */
static bool RebootJobsScheduled = false;
static int RunningTaskCount = 0;
static int MaxRunningTasks = 0;
static int CronLogMinMessages = WARNING;
static bool UseBackgroundWorkers = false;
char *cron_timezone = NULL;
static const struct config_enum_entry cron_message_level_options[] = {
{"debug5", DEBUG5, false},
{"debug4", DEBUG4, false},
{"debug3", DEBUG3, false},
{"debug2", DEBUG2, false},
{"debug1", DEBUG1, false},
{"debug", DEBUG2, true},
{"info", INFO, false},
{"notice", NOTICE, false},
{"warning", WARNING, false},
{"error", ERROR, false},
{"log", LOG, false},
{"fatal", FATAL, false},
{"panic", PANIC, false},
{NULL, 0, false}
};
static const char *cron_error_severity(int elevel);
/*
* _PG_init gets called when the extension is loaded.
*/
void
_PG_init(void)
{
BackgroundWorker worker;
if (IsBinaryUpgrade)
{
return;
}
if (!process_shared_preload_libraries_in_progress)
{
ereport(ERROR, (errmsg("pg_cron can only be loaded via shared_preload_libraries"),
errhint("Add pg_cron to the shared_preload_libraries "
"configuration variable in postgresql.conf.")));
}
DefineCustomStringVariable(
"cron.database_name",
gettext_noop("Database in which pg_cron metadata is kept."),
NULL,
&CronTableDatabaseName,
"postgres",
PGC_POSTMASTER,
GUC_SUPERUSER_ONLY,
NULL, NULL, NULL);
DefineCustomBoolVariable(
"cron.log_statement",
gettext_noop("Log all cron statements prior to execution."),
NULL,
&CronLogStatement,
true,
PGC_POSTMASTER,
GUC_SUPERUSER_ONLY,
NULL, NULL, NULL);
DefineCustomBoolVariable(
"cron.log_run",
gettext_noop("Log all jobs runs into the job_run_details table"),
NULL,
&CronLogRun,
true,
PGC_POSTMASTER,
GUC_SUPERUSER_ONLY,
NULL, NULL, NULL);
DefineCustomBoolVariable(
"cron.enable_superuser_jobs",
gettext_noop("Allow jobs to be scheduled as superuser"),
NULL,
&EnableSuperuserJobs,
true,
PGC_POSTMASTER,
GUC_SUPERUSER_ONLY,
NULL, NULL, NULL);
DefineCustomStringVariable(
"cron.host",
gettext_noop("Hostname to connect to postgres."),
gettext_noop("This setting has no effect when background workers are used."),
&CronHost,
"localhost",
PGC_POSTMASTER,
GUC_SUPERUSER_ONLY,
NULL, NULL, NULL);
DefineCustomBoolVariable(
"cron.use_background_workers",
gettext_noop("Use background workers instead of client sessions."),
NULL,
&UseBackgroundWorkers,
false,
PGC_POSTMASTER,
GUC_SUPERUSER_ONLY,
NULL, NULL, NULL);
DefineCustomBoolVariable(
"cron.launch_active_jobs",
gettext_noop("Launch jobs that are defined as active."),
NULL,
&LaunchActiveJobs,
true,
PGC_SIGHUP,
GUC_SUPERUSER_ONLY,
NULL, NULL, NULL);
if (!UseBackgroundWorkers)
DefineCustomIntVariable(
"cron.max_running_jobs",
gettext_noop("Maximum number of jobs that can run concurrently."),
NULL,
&MaxRunningTasks,
(MaxConnections < 32) ? MaxConnections : 32,
0,
MaxConnections,
PGC_POSTMASTER,
GUC_SUPERUSER_ONLY,
NULL, NULL, NULL);
else
DefineCustomIntVariable(
"cron.max_running_jobs",
gettext_noop("Maximum number of jobs that can run concurrently."),
NULL,
&MaxRunningTasks,
(max_worker_processes - 1 < 5) ? max_worker_processes - 1 : 5,
0,
max_worker_processes - 1,
PGC_POSTMASTER,
GUC_SUPERUSER_ONLY,
NULL, NULL, NULL);
DefineCustomEnumVariable(
"cron.log_min_messages",
gettext_noop("log_min_messages for the launcher bgworker."),
NULL,
&CronLogMinMessages,
WARNING,
cron_message_level_options,
PGC_SIGHUP,
GUC_SUPERUSER_ONLY,
NULL, NULL, NULL);
DefineCustomStringVariable(
"cron.timezone",
gettext_noop("Specify timezone used for cron schedule."),
NULL,
&cron_timezone,
"GMT",
PGC_POSTMASTER,
GUC_SUPERUSER_ONLY,
check_timezone, NULL, NULL);
/* set up common data for all our workers */
worker.bgw_flags = BGWORKER_SHMEM_ACCESS | BGWORKER_BACKEND_DATABASE_CONNECTION;
worker.bgw_start_time = BgWorkerStart_RecoveryFinished;
worker.bgw_restart_time = 1;
#if (PG_VERSION_NUM < 100000)
worker.bgw_main = PgCronLauncherMain;
#endif
worker.bgw_main_arg = Int32GetDatum(0);
worker.bgw_notify_pid = 0;
sprintf(worker.bgw_library_name, "pg_cron");
sprintf(worker.bgw_function_name, "PgCronLauncherMain");
snprintf(worker.bgw_name, BGW_MAXLEN, "pg_cron launcher");
#if (PG_VERSION_NUM >= 110000)
snprintf(worker.bgw_type, BGW_MAXLEN, "pg_cron launcher");
#endif
RegisterBackgroundWorker(&worker);
}
/*
* Signal handler for SIGTERM
* Set a flag to let the main loop to terminate, and set our latch to wake
* it up.
*/
static void
pg_cron_sigterm(SIGNAL_ARGS)
{
got_sigterm = true;
if (MyProc != NULL)
{
SetLatch(&MyProc->procLatch);
}
}
/*
* Signal handler for SIGHUP
* Set a flag to tell the main loop to reload the cron jobs.
*/
static void
pg_cron_sighup(SIGNAL_ARGS)
{
CronJobCacheValid = false;
CronReloadConfig = true;
if (MyProc != NULL)
{
SetLatch(&MyProc->procLatch);
}
}
/*
* pg_cron_cmdTuples -
* mainly copy/pasted from PQcmdTuples
* If the last command was INSERT/UPDATE/DELETE/MOVE/FETCH/COPY, return
* a string containing the number of inserted/affected tuples. If not,
* return "".
*
* XXX: this should probably return an int
*/
static char *
pg_cron_cmdTuples(char *msg)
{
char *p,
*c;
if (!msg)
return "";
if (strncmp(msg, "INSERT ", 7) == 0)
{
p = msg + 7;
/* INSERT: skip oid and space */
while (*p && *p != ' ')
p++;
if (*p == 0)
goto interpret_error; /* no space? */
p++;
}
else if (strncmp(msg, "SELECT ", 7) == 0 ||
strncmp(msg, "DELETE ", 7) == 0 ||
strncmp(msg, "UPDATE ", 7) == 0)
p = msg + 7;
else if (strncmp(msg, "FETCH ", 6) == 0)
p = msg + 6;
else if (strncmp(msg, "MOVE ", 5) == 0 ||
strncmp(msg, "COPY ", 5) == 0)
p = msg + 5;
else
return "";
/* check that we have an integer (at least one digit, nothing else) */
for (c = p; *c; c++)
{
if (!isdigit((unsigned char) *c))
goto interpret_error;
}
if (c == p)
goto interpret_error;
return p;
interpret_error:
ereport(LOG, (errmsg("could not interpret result from server: %s", msg)));
return "";
}
/*
* cron_error_severity --- get string representing elevel
*/
static const char *
cron_error_severity(int elevel)
{
const char *elevel_char;
switch (elevel)
{
case DEBUG1:
elevel_char = "DEBUG1";
break;
case DEBUG2:
elevel_char = "DEBUG2";
break;
case DEBUG3:
elevel_char = "DEBUG3";
break;
case DEBUG4:
elevel_char = "DEBUG4";
break;
case DEBUG5:
elevel_char = "DEBUG5";
break;
case LOG:
elevel_char = "LOG";
break;
case INFO:
elevel_char = "INFO";
break;
case NOTICE:
elevel_char = "NOTICE";
break;
case WARNING:
elevel_char = "WARNING";
break;
case ERROR:
elevel_char = "ERROR";
break;
case FATAL:
elevel_char = "FATAL";
break;
case PANIC:
elevel_char = "PANIC";
break;
default:
elevel_char = "???";
break;
}
return elevel_char;
}
/*
* bgw_generate_returned_message -
* generates the message to be inserted into the job_run_details table
* first part is comming from error_severity (elog.c)
*/
static void
bgw_generate_returned_message(StringInfoData *display_msg, ErrorData edata)
{
const char *prefix;
switch (edata.elevel)
{
case DEBUG1:
case DEBUG2:
case DEBUG3:
case DEBUG4:
case DEBUG5:
prefix = gettext_noop("DEBUG");
break;
case LOG:
#if (PG_VERSION_NUM >= 100000)
case LOG_SERVER_ONLY:
#endif
prefix = gettext_noop("LOG");
break;
case INFO:
prefix = gettext_noop("INFO");
break;
case NOTICE:
prefix = gettext_noop("NOTICE");
break;
case WARNING:
prefix = gettext_noop("WARNING");
break;
case ERROR:
prefix = gettext_noop("ERROR");
break;
case FATAL:
prefix = gettext_noop("FATAL");
break;
case PANIC:
prefix = gettext_noop("PANIC");
break;
default:
prefix = "???";
break;
}
appendStringInfo(display_msg, "%s: %s", prefix, edata.message);
if (edata.detail != NULL)
appendStringInfo(display_msg, "\nDETAIL: %s", edata.detail);
if (edata.hint != NULL)
appendStringInfo(display_msg, "\nHINT: %s", edata.hint);
if (edata.context != NULL)
appendStringInfo(display_msg, "\nCONTEXT: %s", edata.context);
}
/*
* PgCronLauncherMain is the main entry-point for the background worker
* that performs tasks.
*/
void
PgCronLauncherMain(Datum arg)
{
MemoryContext CronLoopContext = NULL;
struct rlimit limit;
/* Establish signal handlers before unblocking signals. */
pqsignal(SIGHUP, pg_cron_sighup);
pqsignal(SIGINT, SIG_IGN);
pqsignal(SIGTERM, pg_cron_sigterm);
/* We're now ready to receive signals */
BackgroundWorkerUnblockSignals();
/* Connect to our database */
#if (PG_VERSION_NUM < 110000)
BackgroundWorkerInitializeConnection(CronTableDatabaseName, NULL);
#else
BackgroundWorkerInitializeConnection(CronTableDatabaseName, NULL, 0);
#endif
/* Make pg_cron recognisable in pg_stat_activity */
pgstat_report_appname("pg_cron scheduler");
/*
* Mark anything that was in progress before the database restarted as
* failed.
*/
MarkPendingRunsAsFailed();
/* Determine how many tasks we can run concurrently */
if (MaxConnections < MaxRunningTasks)
{
MaxRunningTasks = MaxConnections;
}
if (max_files_per_process < MaxRunningTasks)
{
MaxRunningTasks = max_files_per_process;
}
if (getrlimit(RLIMIT_NOFILE, &limit) != 0 &&
limit.rlim_cur < (uint32) MaxRunningTasks)
{
MaxRunningTasks = limit.rlim_cur;
}
if (UseBackgroundWorkers && max_worker_processes - 1 < MaxRunningTasks)
{
MaxRunningTasks = max_worker_processes - 1;
}
if (MaxRunningTasks <= 0)
{
MaxRunningTasks = 1;
}
CronLoopContext = AllocSetContextCreate(CurrentMemoryContext,
"pg_cron loop context",
ALLOCSET_DEFAULT_MINSIZE,
ALLOCSET_DEFAULT_INITSIZE,
ALLOCSET_DEFAULT_MAXSIZE);
InitializeJobMetadataCache();
InitializeTaskStateHash();
ereport(LOG, (errmsg("pg_cron scheduler started")));
/* set the desired log_min_messages */
SetConfigOption("log_min_messages", cron_error_severity(CronLogMinMessages),
PGC_POSTMASTER, PGC_S_OVERRIDE);
MemoryContextSwitchTo(CronLoopContext);
while (!got_sigterm)
{
List *taskList = NIL;
TimestampTz currentTime = 0;
AcceptInvalidationMessages();
if (CronReloadConfig)
{
/* set the desired log_min_messages */
ProcessConfigFile(PGC_SIGHUP);
SetConfigOption("log_min_messages", cron_error_severity(CronLogMinMessages),
PGC_POSTMASTER, PGC_S_OVERRIDE);
CronReloadConfig = false;
}
/*
* Both CronReloadConfig and CronJobCacheValid are triggered by SIGHUP.
* ProcessConfigFile should come first, because RefreshTaskHash depends
* on settings that might have changed.
*/
if (!CronJobCacheValid)
{
RefreshTaskHash();
}
taskList = CurrentTaskList();
currentTime = GetCurrentTimestamp();
StartAllPendingRuns(taskList, currentTime);
WaitForCronTasks(taskList);
ManageCronTasks(taskList, currentTime);
MemoryContextReset(CronLoopContext);
}
ereport(LOG, (errmsg("pg_cron scheduler shutting down")));
/* return error code to trigger restart */
proc_exit(1);
}
/*
* StartPendingRuns goes through the list of tasks and kicks of
* runs for tasks that should start, taking clock changes into
* into consideration.
*/
static void
StartAllPendingRuns(List *taskList, TimestampTz currentTime)
{
static TimestampTz lastMinute = 0;
int minutesPassed = 0;
ListCell *taskCell = NULL;
ClockProgress clockProgress;
if (!RebootJobsScheduled)
{
/* find jobs with @reboot as a schedule */
foreach(taskCell, taskList)
{
CronTask *task = (CronTask *) lfirst(taskCell);
CronJob *cronJob = GetCronJob(task->jobId);
entry *schedule = &cronJob->schedule;
if (schedule->flags & WHEN_REBOOT &&
task->isActive)
{
task->pendingRunCount += 1;
}
}
RebootJobsScheduled = true;
}
foreach(taskCell, taskList)
{
CronTask *task = (CronTask *) lfirst(taskCell);
if (task->secondsInterval > 0 && task->isActive)
{
/*
* For interval jobs, if a task takes longer than the interval,
* we only queue up once. So if a task that is supposed to run
* every 30 seconds takes 5 minutes, we start another run
* immediately after 5 minutes, but then return to regular cadence.
*/
if (task->pendingRunCount == 0 &&
TimestampDifferenceExceeds(task->lastStartTime, currentTime,
task->secondsInterval * 1000))
{
task->pendingRunCount += 1;
}
}
}
if (lastMinute == 0)
{
lastMinute = TimestampMinuteStart(currentTime);
}
minutesPassed = MinutesPassed(lastMinute, currentTime);
if (minutesPassed == 0)
{
/* wait for new minute */
return;
}
/* use Vixie cron logic for clock jumps */
if (minutesPassed > (3*MINUTE_COUNT))
{
/* clock jumped forward by more than 3 hours */
clockProgress = CLOCK_CHANGE;
}
else if (minutesPassed > 5)
{
/* clock went forward by more than 5 minutes (DST?) */
clockProgress = CLOCK_JUMP_FORWARD;
}
else if (minutesPassed > 0)
{
/* clock went forward by 1-5 minutes */
clockProgress = CLOCK_PROGRESSED;
}
else if (minutesPassed > -(3*MINUTE_COUNT))
{
/* clock jumped backwards by less than 3 hours (DST?) */
clockProgress = CLOCK_JUMP_BACKWARD;
}
else
{
/* clock jumped backwards 3 hours or more */
clockProgress = CLOCK_CHANGE;
}
foreach(taskCell, taskList)
{
CronTask *task = (CronTask *) lfirst(taskCell);
if (!task->isActive)
{
/*
* The job has been unscheduled, so we should not schedule
* new runs. The task will be safely removed on the next call
* to ManageCronTask.
*/
continue;
}
StartPendingRuns(task, clockProgress, lastMinute, currentTime);
}
/*
* If the clock jump backwards then we avoid repeating the fixed-time
* tasks by preserving the last minute from before the clock jump,
* until the clock has caught up (clockProgress will be
* CLOCK_JUMP_BACKWARD until then).
*/
if (clockProgress != CLOCK_JUMP_BACKWARD)
{
lastMinute = TimestampMinuteStart(currentTime);
}
}
/*
* StartPendingRuns kicks off pending runs for a task if it
* should start, taking clock changes into consideration.
*/
static void
StartPendingRuns(CronTask *task, ClockProgress clockProgress,
TimestampTz lastMinute, TimestampTz currentTime)
{
CronJob *cronJob = GetCronJob(task->jobId);
entry *schedule = &cronJob->schedule;
TimestampTz virtualTime = lastMinute;
TimestampTz currentMinute = TimestampMinuteStart(currentTime);
switch (clockProgress)
{
case CLOCK_PROGRESSED:
{
/*
* case 1: minutesPassed is a small positive number
* run jobs for each virtual minute until caught up.
*/
do
{
virtualTime = TimestampTzPlusMilliseconds(virtualTime,
60*1000);
if (ShouldRunTask(schedule, virtualTime, true, true))
{
task->pendingRunCount += 1;
}
}
while (virtualTime < currentMinute);
break;
}
case CLOCK_JUMP_FORWARD:
{
/*
* case 2: minutesPassed is a medium-sized positive number,
* for example because we went to DST run wildcard
* jobs once, then run any fixed-time jobs that would
* otherwise be skipped if we use up our minute
* (possible, if there are a lot of jobs to run) go
* around the loop again so that wildcard jobs have
* a chance to run, and we do our housekeeping
*/
/* run fixed-time jobs for each minute missed */
do
{
virtualTime = TimestampTzPlusMilliseconds(virtualTime,
60*1000);
if (ShouldRunTask(schedule, virtualTime, false, true))
{
task->pendingRunCount += 1;
}
} while (virtualTime < currentMinute);
/* run wildcard jobs for current minute */
if (ShouldRunTask(schedule, currentMinute, true, false))
{
task->pendingRunCount += 1;
}
break;
}
case CLOCK_JUMP_BACKWARD:
{
/*
* case 3: timeDiff is a small or medium-sized
* negative num, eg. because of DST ending just run
* the wildcard jobs. The fixed-time jobs probably
* have already run, and should not be repeated
* virtual time does not change until we are caught up
*/
if (ShouldRunTask(schedule, currentMinute, true, false))
{
task->pendingRunCount += 1;
}
break;
}
default:
{
/*
* other: time has changed a *lot*, skip over any
* intermediate fixed-time jobs and go back to
* normal operation.
*/
if (ShouldRunTask(schedule, currentMinute, true, true))
{
task->pendingRunCount += 1;
}
}
}
}
/*
* MinutesPassed returns the number of minutes between startTime and
* stopTime rounded down to the closest integer.
*/
static int
MinutesPassed(TimestampTz startTime, TimestampTz stopTime)
{
int microsPassed = 0;
long secondsPassed = 0;
int minutesPassed = 0;
TimestampDifference(startTime, stopTime,
&secondsPassed, µsPassed);
minutesPassed = secondsPassed / 60;
return minutesPassed;
}
/*
* TimestampMinuteEnd returns the timestamp at the start of the
* current minute for the given time.
*/
static TimestampTz
TimestampMinuteStart(TimestampTz time)
{
TimestampTz result = 0;
#ifdef HAVE_INT64_TIMESTAMP
result = time - time % 60000000;
#else
result = (long) time - (long) time % 60;
#endif
return result;
}
/*
* TimestampMinuteEnd returns the timestamp at the start of the
* next minute from the given time.
*/
static TimestampTz
TimestampMinuteEnd(TimestampTz time)
{
TimestampTz result = TimestampMinuteStart(time);
#ifdef HAVE_INT64_TIMESTAMP
result += 60000000;
#else
result += 60;
#endif
return result;
}
/*
* ShouldRunTask returns whether a job should run in the current
* minute according to its schedule.
*/
static bool
ShouldRunTask(entry *schedule, TimestampTz currentTime, bool doWild,
bool doNonWild)
{
pg_time_t currentTime_t = timestamptz_to_time_t(currentTime);
pg_time_t tomorrowTime_t = timestamptz_to_time_t(currentTime + USECS_PER_DAY);
struct pg_tm* cur_tm = pg_localtime(¤tTime_t, pg_tzset(cron_timezone));
int minute = cur_tm->tm_min -FIRST_MINUTE;
int hour = cur_tm->tm_hour -FIRST_HOUR;
int dayOfMonth = cur_tm->tm_mday -FIRST_DOM;
int month = cur_tm->tm_mon +1 -FIRST_MONTH;
int dayOfWeek = cur_tm->tm_wday -FIRST_DOW;
/*
* pg_localtime returns a pointer to a global struct,
* so cur_tm cannot be used after this point.
*/
struct pg_tm* tomorrow_tm = pg_localtime(&tomorrowTime_t, pg_tzset(cron_timezone));
bool lastdom = (schedule->flags & DOM_LAST) != 0 && tomorrow_tm->tm_mday == 1;
bool thisdom = lastdom || bit_test(schedule->dom, dayOfMonth) != 0;
bool thisdow = bit_test(schedule->dow, dayOfWeek);
if (bit_test(schedule->minute, minute) &&
bit_test(schedule->hour, hour) &&
bit_test(schedule->month, month) &&
( (schedule->flags & (DOM_STAR|DOW_STAR)) != 0
? (thisdom && thisdow) : (thisdom) || thisdow)) {
if ((doNonWild && !(schedule->flags & (MIN_STAR|HR_STAR)))
|| (doWild && (schedule->flags & (MIN_STAR|HR_STAR))))
{
return true;
}
}
return false;
}