Function pgarch_MainLoop

src/backend/postmaster/pgarch.c:298–371

* pgarch_MainLoop * * Main loop for archiver */

 * Main loop for archiver
 */
static void
pgarch_MainLoop(void)
{
	pg_time_t	last_copy_time = 0;
	bool		time_to_stop;

	/*
	 * There shouldn't be anything for the archiver to do except to wait for a
	 * signal ... however, the archiver exists to protect our data, so she
	 * wakes up occasionally to allow herself to be proactive.
	 */
	do
	{
		ResetLatch(MyLatch);

		/* When we get SIGUSR2, we do one more archive cycle, then exit */
		time_to_stop = ready_to_stop;

		/* Check for barrier events and config update */
		HandlePgArchInterrupts();

		/*
		 * If we've gotten SIGTERM, we normally just sit and do nothing until
		 * SIGUSR2 arrives.  However, that means a random SIGTERM would
		 * disable archiving indefinitely, which doesn't seem like a good
		 * idea.  If more than 60 seconds pass since SIGTERM, exit anyway, so
		 * that the postmaster can start a new archiver if needed.
		 */
		if (ShutdownRequestPending)
		{
			time_t		curtime = time(NULL);

			if (last_sigterm_time == 0)
				last_sigterm_time = curtime;
			else if ((unsigned int) (curtime - last_sigterm_time) >=
					 (unsigned int) 60)
				break;
		}

		/* Do what we're here for */
		pgarch_ArchiverCopyLoop();
		last_copy_time = time(NULL);

		/*
		 * Sleep until a signal is received, or until a poll is forced by
		 * PGARCH_AUTOWAKE_INTERVAL having passed since last_copy_time, or
		 * until postmaster dies.
		 */
		if (!time_to_stop)		/* Don't wait during last iteration */
		{
			pg_time_t	curtime = (pg_time_t) time(NULL);
			int			timeout;

			timeout = PGARCH_AUTOWAKE_INTERVAL - (curtime - last_copy_time);
			if (timeout > 0)
			{
				int			rc;