From 868ab8923a2ec977faafec97ecafac0c3159c1b2 Mon Sep 17 00:00:00 2001
From: Florian Weimer <fweimer@redhat.com>
Date: Thu, 13 Jun 2024 18:56:30 +0200
Subject: [PATCH] resolv: Track single-request fallback via _res._flags (bug
 31476)

This avoids changing _res.options, which inteferes with change
detection as part of automatic reloading of /etc/resolv.conf.

Reviewed-by: DJ Delorie <dj@redhat.com>

Conflict:NA
Reference:https://sourceware.org/git/?p=glibc.git;a=patch;h=868ab8923a2ec977faafec97ecafac0c3159c1b2

---
 resolv/res_send.c        | 12 +++++++-----
 resolv/resolv-internal.h |  2 ++
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/resolv/res_send.c b/resolv/res_send.c
index 54226a2e..701c089a 100644
--- a/resolv/res_send.c
+++ b/resolv/res_send.c
@@ -942,9 +942,11 @@ send_dg(res_state statp,
 		seconds /= statp->nscount;
 	if (seconds <= 0)
 		seconds = 1;
-	bool single_request_reopen = (statp->options & RES_SNGLKUPREOP) != 0;
-	bool single_request = (((statp->options & RES_SNGLKUP) != 0)
-			       | single_request_reopen);
+	bool single_request_reopen = ((statp->options & RES_SNGLKUPREOP)
+				      || (statp->_flags & RES_F_SNGLKUPREOP));
+	bool single_request = ((statp->options & RES_SNGLKUP)
+			       || (statp->_flags & RES_F_SNGLKUP)
+			       || single_request_reopen);
 	int save_gotsomewhere = *gotsomewhere;
 
 	int retval;
@@ -1001,14 +1003,14 @@ send_dg(res_state statp,
 		       have received the first answer.  */
 		    if (!single_request)
 		      {
-			statp->options |= RES_SNGLKUP;
+			statp->_flags |= RES_F_SNGLKUP;
 			single_request = true;
 			*gotsomewhere = save_gotsomewhere;
 			goto retry;
 		      }
 		    else if (!single_request_reopen)
 		      {
-			statp->options |= RES_SNGLKUPREOP;
+			statp->_flags |= RES_F_SNGLKUPREOP;
 			single_request_reopen = true;
 			*gotsomewhere = save_gotsomewhere;
 			__res_iclose (statp, false);
diff --git a/resolv/resolv-internal.h b/resolv/resolv-internal.h
index 216e47ed..fa92d318 100644
--- a/resolv/resolv-internal.h
+++ b/resolv/resolv-internal.h
@@ -26,6 +26,8 @@
 #define RES_F_VC        0x00000001 /* Socket is TCP.  */
 #define RES_F_CONN      0x00000002 /* Socket is connected.  */
 #define RES_F_EDNS0ERR  0x00000004 /* EDNS0 caused errors.  */
+#define RES_F_SNGLKUP	0x00200000 /* Private version of RES_SNGLKUP.  */
+#define RES_F_SNGLKUPREOP 0x00400000 /* Private version of RES_SNGLKUPREOP.  */
 
 /* Legacy function.  This needs to be removed once all NSS modules
    have been adjusted.  */
-- 
2.33.0

