0001-Emulate-sigprocmask-not-sigsetmask-on-Windows.patch

From b21140e9b3f593b46c3bb4782c6bf84ca248dc15 Mon Sep 17 00:00:00 2001
From: Thomas Munro <thomas.munro@gmail.com>
Date: Fri, 15 Jul 2022 14:35:01 +1200
Subject: [PATCH] Emulate sigprocmask(), not sigsetmask(), on Windows.

Since commit a65e0864, we've required Unix systems to have
sigprocmask().  For Windows we still emulated the old deprecated 4.2BSD
function sigsetmask().  Emulate sigprocmask() instead, for consistency.

Discussion: https://postgr.es/m/3153247.1657834482%40sss.pgh.pa.us
---
 src/backend/port/win32/signal.c | 29 +++++++++++++++++++++++------
 src/include/libpq/pqsignal.h    | 11 +++++++----
 2 files changed, 30 insertions(+), 10 deletions(-)

diff --git a/src/backend/port/win32/signal.c b/src/backend/port/win32/signal.c
index b71164d8db..53b93a50b2 100644
--- a/src/backend/port/win32/signal.c
+++ b/src/backend/port/win32/signal.c
@@ -112,7 +112,7 @@ pgwin32_signal_initialize(void)
 /*
  * Dispatch all signals currently queued and not blocked
  * Blocked signals are ignored, and will be fired at the time of
- * the pqsigsetmask() call.
+ * the pqsigprocmask() call.
  */
 void
 pgwin32_dispatch_queued_signals(void)
@@ -154,12 +154,29 @@ pgwin32_dispatch_queued_signals(void)
 
 /* signal masking. Only called on main thread, no sync required */
 int
-pqsigsetmask(int mask)
+pqsigprocmask(int how, const sigset_t *set, sigset_t *oset)
 {
-	int			prevmask;
+	if (oset)
+		*oset = pg_signal_mask;
 
-	prevmask = pg_signal_mask;
-	pg_signal_mask = mask;
+	if (!set)
+		return 0;
+
+	switch (how)
+	{
+		case SIG_BLOCK:
+			pg_signal_mask |= *set;
+			break;
+		case SIG_UNBLOCK:
+			pg_signal_mask &= ~*set;
+			break;
+		case SIG_SETMASK:
+			pg_signal_mask = *set;
+			break;
+		default:
+			errno = EINVAL;
+			return -1;
+	}
 
 	/*
 	 * Dispatch any signals queued up right away, in case we have unblocked
@@ -167,7 +184,7 @@ pqsigsetmask(int mask)
 	 */
 	pgwin32_dispatch_queued_signals();
 
-	return prevmask;
+	return 0;
 }
 
 
diff --git a/src/include/libpq/pqsignal.h b/src/include/libpq/pqsignal.h
index 41227a30e2..d17ddb787e 100644
--- a/src/include/libpq/pqsignal.h
+++ b/src/include/libpq/pqsignal.h
@@ -15,15 +15,18 @@
 
 #include <signal.h>
 
-#ifndef WIN32
 #define PG_SETMASK(mask)	sigprocmask(SIG_SETMASK, mask, NULL)
-#else
+
+#ifdef WIN32
 /* Emulate POSIX sigset_t APIs on Windows */
 typedef int sigset_t;
 
-extern int	pqsigsetmask(int mask);
+extern int	pqsigprocmask(int how, const sigset_t *set, sigset_t *oset);
 
-#define PG_SETMASK(mask)		pqsigsetmask(*(mask))
+#define SIG_BLOCK				1
+#define SIG_UNBLOCK				2
+#define SIG_SETMASK				3
+#define sigprocmask(how, set, oset) pqsigprocmask((how), (set), (oset))
 #define sigemptyset(set)		(*(set) = 0)
 #define sigfillset(set)			(*(set) = ~0)
 #define sigaddset(set, signum)	(*(set) |= (sigmask(signum)))
-- 
2.36.1