From 99698140394a644e90d46798ae34e66a141a8d98 Mon Sep 17 00:00:00 2001
From: Heikki Linnakangas <heikki@enterprisedb.com>
Date: Wed, 4 Mar 2009 13:56:40 +0000
Subject: [PATCH] Reload config file in startup process on SIGHUP.

Fujii Masao
---
 src/backend/access/transam/xlog.c   | 21 +++++++++++++++++++--
 src/backend/postmaster/postmaster.c |  2 ++
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index bc8372ce3a..3539e9a946 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -429,6 +429,7 @@ static bool InRedo = false;
 /*
  * Flag set by interrupt handlers for later service in the redo loop.
  */
+static volatile sig_atomic_t got_SIGHUP = false;
 static volatile sig_atomic_t shutdown_requested = false;
 /*
  * Flag set when executing a restore command, to tell SIGTERM signal handler
@@ -5362,6 +5363,15 @@ StartupXLOG(void)
 				}
 #endif
 
+				/*
+				 * Check if we were requested to re-read config file.
+				 */
+				if (got_SIGHUP)
+				{
+					got_SIGHUP = false;
+					ProcessConfigFile(PGC_SIGHUP);
+				}
+
 				/*
 				 * Check if we were requested to exit without finishing
 				 * recovery.
@@ -7641,6 +7651,13 @@ startupproc_quickdie(SIGNAL_ARGS)
 }
 
 
+/* SIGHUP: set flag to re-read config file at next convenient time */
+static void
+StartupProcSigHupHandler(SIGNAL_ARGS)
+{
+	got_SIGHUP = true;
+}
+
 /* SIGTERM: set flag to abort redo and exit */
 static void
 StartupProcShutdownHandler(SIGNAL_ARGS)
@@ -7667,8 +7684,8 @@ StartupProcessMain(void)
 	/*
 	 * Properly accept or ignore signals the postmaster might send us
 	 */
-	pqsignal(SIGHUP, SIG_IGN);	/* ignore config file updates */
-	pqsignal(SIGINT, SIG_IGN);		/* ignore query cancel */
+	pqsignal(SIGHUP, StartupProcSigHupHandler);	 /* reload config file */
+	pqsignal(SIGINT, SIG_IGN);					/* ignore query cancel */
 	pqsignal(SIGTERM, StartupProcShutdownHandler); /* request shutdown */
 	pqsignal(SIGQUIT, startupproc_quickdie);		/* hard crash time */
 	pqsignal(SIGALRM, SIG_IGN);
diff --git a/src/backend/postmaster/postmaster.c b/src/backend/postmaster/postmaster.c
index a427a1b36e..b1e5bb8617 100644
--- a/src/backend/postmaster/postmaster.c
+++ b/src/backend/postmaster/postmaster.c
@@ -1949,6 +1949,8 @@ SIGHUP_handler(SIGNAL_ARGS)
 				(errmsg("received SIGHUP, reloading configuration files")));
 		ProcessConfigFile(PGC_SIGHUP);
 		SignalChildren(SIGHUP);
+		if (StartupPID != 0)
+			signal_child(StartupPID, SIGHUP);
 		if (BgWriterPID != 0)
 			signal_child(BgWriterPID, SIGHUP);
 		if (WalWriterPID != 0)
-- 
2.39.5