From fa974811a9b8ab688f7d39b263c49bebb4d07f6f Mon Sep 17 00:00:00 2001
From: Aram Sargsyan <aram@isc.org>
Date: Wed, 21 May 2025 15:27:53 +0000
Subject: [PATCH] Emit a ISC_R_CANCELED result instead of ISC_R_SHUTTINGDOWN

When request manager shuts down, it also shuts down all its ongoing
requests. Currently it calls their callback functions with a
ISC_R_SHUTTINGDOWN result code for the request. Since a request
manager can shutdown not only during named shutdown but also during
named reconfiguration, instead of sending ISC_R_SHUTTINGDOWN result
code send a ISC_R_CANCELED code to avoid confusion and errors with
the expectation that a ISC_R_SHUTTINGDOWN result code can only be
received during actual shutdown of named.

All the callback functions which are passed to either the
dns_request_create() or the dns_request_createraw() functions have
been analyzed to confirm that they can process both the
ISC_R_SHUTTINGDOWN and ISC_R_CANCELED result codes. Changes were
made where it was necessary.

(cherry picked from commit f4cd307c6b705e13c45136ac4dc49e262a598297)
---
 bin/tests/system/xfer/tests.sh |  2 +-
 lib/dns/request.c              | 10 +++++-----
 lib/dns/zone.c                 |  2 ++
 3 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/bin/tests/system/xfer/tests.sh b/bin/tests/system/xfer/tests.sh
index 8b44dcfd98..2ba58710e9 100755
--- a/bin/tests/system/xfer/tests.sh
+++ b/bin/tests/system/xfer/tests.sh
@@ -763,7 +763,7 @@ sleep 1
 # Reconfigure named while zone transfer attempt is in progress.
 $RNDCCMD 10.53.0.6 reconfig 2>&1 | sed 's/^/ns6 /' | cat_i
 # Confirm that the ongoing SOA request was canceled, caused by the reconfiguratoin.
-retry_quiet 60 wait_for_message "refresh: request result: shutting down" || tmp=1
+retry_quiet 60 wait_for_message "refresh: request result: operation canceled" || tmp=1
 if test $tmp != 0; then echo_i "failed"; fi
 status=$((status + tmp))
 
diff --git a/lib/dns/request.c b/lib/dns/request.c
index c2ba096dbf..38130e80bf 100644
--- a/lib/dns/request.c
+++ b/lib/dns/request.c
@@ -143,7 +143,7 @@ dns_requestmgr_create(isc_mem_t *mctx, isc_loopmgr_t *loopmgr,
 	for (size_t i = 0; i < nloops; i++) {
 		ISC_LIST_INIT(requestmgr->requests[i]);
 
-		/* unreferenced in requests_shutdown() */
+		/* unreferenced in requests_cancel() */
 		isc_loop_ref(isc_loop_get(requestmgr->loopmgr, i));
 	}
 
@@ -169,7 +169,7 @@ dns_requestmgr_create(isc_mem_t *mctx, isc_loopmgr_t *loopmgr,
 }
 
 static void
-requests_shutdown(void *arg) {
+requests_cancel(void *arg) {
 	dns_requestmgr_t *requestmgr = arg;
 	dns_request_t *request = NULL, *next = NULL;
 	uint32_t tid = isc_tid();
@@ -181,7 +181,7 @@ requests_shutdown(void *arg) {
 			/* The callback has been already scheduled */
 			continue;
 		}
-		req_sendevent(request, ISC_R_SHUTTINGDOWN);
+		req_sendevent(request, ISC_R_CANCELED);
 	}
 
 	isc_loop_unref(isc_loop_get(requestmgr->loopmgr, tid));
@@ -217,12 +217,12 @@ dns_requestmgr_shutdown(dns_requestmgr_t *requestmgr) {
 
 		if (i == tid) {
 			/* Run the current loop synchronously */
-			requests_shutdown(requestmgr);
+			requests_cancel(requestmgr);
 			continue;
 		}
 
 		isc_loop_t *loop = isc_loop_get(requestmgr->loopmgr, i);
-		isc_async_run(loop, requests_shutdown, requestmgr);
+		isc_async_run(loop, requests_cancel, requestmgr);
 	}
 }
 
diff --git a/lib/dns/zone.c b/lib/dns/zone.c
index 816e801bf7..845902b160 100644
--- a/lib/dns/zone.c
+++ b/lib/dns/zone.c
@@ -13609,6 +13609,7 @@ stub_callback(void *arg) {
 	case ISC_R_SUCCESS:
 		break;
 	case ISC_R_SHUTTINGDOWN:
+	case ISC_R_CANCELED:
 		goto exiting;
 	case ISC_R_TIMEDOUT:
 		if (!DNS_ZONE_FLAG(zone, DNS_ZONEFLG_NOEDNS)) {
@@ -13953,6 +13954,7 @@ refresh_callback(void *arg) {
 	case ISC_R_SUCCESS:
 		break;
 	case ISC_R_SHUTTINGDOWN:
+	case ISC_R_CANCELED:
 		goto exiting;
 	case ISC_R_TIMEDOUT:
 		if (!DNS_ZONE_FLAG(zone, DNS_ZONEFLG_NOEDNS)) {