From f0d75b778ee7bfd0feb368b51027943085a54705 Mon Sep 17 00:00:00 2001
From: Petr Menšík <pemensik@redhat.com>
Date: Mar 26 2021 13:05:56 +0000
Subject: [PATCH 1/2] Add support for dns library without libinterface


BIND 9.16.12 and more recent have removed numeric versioning of library.
Instead it just contain complete text version. Extract numbers from it
and export it in similar manner.

---

diff --git a/configure.ac b/configure.ac
index e8bce4a..ca7ef18 100644
--- a/configure.ac
+++ b/configure.ac
@@ -90,19 +90,31 @@ AC_CHECK_LIB([krb5], [krb5_cc_initialize], [],
 AC_CHECK_LIB([uuid], [uuid_unparse], [],
 	AC_MSG_ERROR([Install UUID library development files]))
 
+AC_LANG(C)
 # Check version of libdns
 AC_MSG_CHECKING([libdns version])
-AC_TRY_RUN([
+AC_RUN_IFELSE([AC_LANG_PROGRAM([
 #include <stdio.h>
 #include <dns/version.h>
-int main(void) {
-	printf("%d\n", dns_libinterface);
-	return 0;
-}],[LIBDNS_VERSION_MAJOR=`./conftest$ac_exeext`
+],[ printf("%d\n", dns_libinterface) ])], [
+    LIBDNS_VERSION_MAJOR=`./conftest$ac_exeext`
+    AC_DEFINE_UNQUOTED([LIBDNS_VERSION_MAJOR], [$LIBDNS_VERSION_MAJOR],
+    [Define libdns version])], [
+    AC_RUN_IFELSE([AC_LANG_PROGRAM([[
+#include <stdio.h>
+#include <dns/version.h>
+]],[[
+	unsigned major, minor, patch, scanned;
+	/* emulate dns_libinterface from minor and patch version */
+        scanned = sscanf(dns_version, "%u.%u.%u", &major, &minor, &patch);
+        printf("%02d%02d\n", minor, patch);
+	return !(scanned == 3 && major == 9);
+    ]])], [
+    LIBDNS_VERSION_MAJOR=`./conftest$ac_exeext`
     AC_DEFINE_UNQUOTED([LIBDNS_VERSION_MAJOR], [$LIBDNS_VERSION_MAJOR],
     [Define libdns version])],
-[AC_MSG_ERROR([Can't obtain libdns version.])],
-[AC_MSG_ERROR([Cross compiling is not supported.])]
+    [AC_MSG_ERROR([Can't obtain libdns version.])])
+], [AC_MSG_ERROR([Cross compiling is not supported.])]
 )
 
 dnl isc_errno_toresult() was not available in older header files

From 1d03c1e5b2e6c932c3a773518a0224d6bcd9d28b Mon Sep 17 00:00:00 2001
From: Petr Menšík <pemensik@redhat.com>
Date: Mar 26 2021 13:05:56 +0000
Subject: [PATCH 2/2] rwlock initialization does not return value


API has changed, it no longer returns a value in isc_rwlock_init.
It returned always ISC_SUCCCESS on 9.16 anyway, so skip the check
on every 9.16 build.

---

diff --git a/src/fwd_register.c b/src/fwd_register.c
index cc9764b..fcbd66f 100644
--- a/src/fwd_register.c
+++ b/src/fwd_register.c
@@ -6,6 +6,7 @@
 #include <isc/util.h>
 #include <dns/name.h>
 
+#include "config.h"
 #include "rbt_helper.h"
 #include "fwd_register.h"
 #include "util.h"
@@ -35,7 +36,11 @@ fwdr_create(isc_mem_t *mctx, fwd_register_t **fwdrp)
 	ZERO_PTR(fwdr);
 	isc_mem_attach(mctx, &fwdr->mctx);
 	CHECK(dns_rbt_create(mctx, NULL, NULL, &fwdr->rbt));
+#if LIBDNS_VERSION_MAJOR >= 1600
+	(void)isc_rwlock_init(&fwdr->rwlock, 0, 0);
+#else
 	CHECK(isc_rwlock_init(&fwdr->rwlock, 0, 0));
+#endif
 
 	*fwdrp = fwdr;
 	return ISC_R_SUCCESS;
diff --git a/src/zone_register.c b/src/zone_register.c
index 07b1546..28d9b7a 100644
--- a/src/zone_register.c
+++ b/src/zone_register.c
@@ -12,6 +12,7 @@
 #include <dns/result.h>
 #include <dns/zone.h>
 
+#include "config.h"
 #include "fs.h"
 #include "ldap_driver.h"
 #include "log.h"
@@ -115,7 +116,12 @@ zr_create(isc_mem_t *mctx, ldap_instance_t *ldap_inst,
 	ZERO_PTR(zr);
 	isc_mem_attach(mctx, &zr->mctx);
 	CHECK(dns_rbt_create(mctx, delete_zone_info, mctx, &zr->rbt));
+#if LIBDNS_VERSION_MAJOR >= 1600
+	/* Never fails on BIND 9.16, even it if returns value */
+	(void)isc_rwlock_init(&zr->rwlock, 0, 0);
+#else
 	CHECK(isc_rwlock_init(&zr->rwlock, 0, 0));
+#endif
 	zr->global_settings = glob_settings;
 	zr->ldap_inst = ldap_inst;