Backport haproxy/haproxy@d3c20b0 into stable until 3.1.1 is released

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haproxy/patches-stable/0001-bug-minor-register-sigint-handler-in-signal_init.patch

@@ -0,0 +1,41 @@
+From d3c20b02469dea6f46369bb91965d8b4924bb2b7 Mon Sep 17 00:00:00 2001
+From: Valentine Krasnobaeva <[email protected]>
+Date: Mon, 2 Dec 2024 14:47:17 +0100
+Subject: [PATCH] BUG/MINOR: signal: register default handler for SIGINT in
+ signal_init()
+
+When haproxy is launched in a background and in a subshell (see example below),
+according to POSIX standard (2.11. Signals and Error Handling), it inherits
+from the subshell SIG_IGN signal handler for SIGINT and SIGQUIT.
+
+	$ (./haproxy -f env4.cfg &)
+
+So, when haproxy is lanched like this, it doesn't stop upon receiving
+the SIGINT. This can be a root cause of some unexpected timeouts, when haproxy
+is started under VTest, as VTest sends to the process SIGINT in order to
+terminate it. To fix this, let's explicitly register the default signal
+handler for the SIGINT in signal_init() initcall.
+
+This should be backported in all stable versions.
+---
+ src/signal.c | 7 +++++++
+ 1 file changed, 7 insertions(+)
+
+diff --git a/src/signal.c b/src/signal.c
+index 1bb60eb82b6cc..9dfb5dc4b51b5 100644
+--- a/src/signal.c
++++ b/src/signal.c
+@@ -106,6 +106,13 @@ static void signal_init()
+ {
+ 	int sig;
+
++	/* Need to register the handler for SIGINT explicitly, as we can be
++	 * laucned within the subshell and at background:
++	 * $ (./haproxy -f env4.cfg &). According to POSIX standard
++	 * (2.11. Signals and Error Handling), we will inherit from the subshell
++	 * in this case SIG_IGN signal handler for SIGINT and SIGQUIT.
++	 */
++	signal(SIGINT, SIG_DFL);
+ 	signal_queue_len = 0;
+ 	memset(signal_queue, 0, sizeof(signal_queue));
+ 	memset(signal_state, 0, sizeof(signal_state));