add preun and post

(cherry picked from commit ca03435dbae8f8b482a4d900993233956e1de080)

nss-mdns.spec

@@ -1,6 +1,6 @@
 Name:            nss-mdns
 Version:         0.15.1
-Release:         2
+Release:         3
 Summary:         Host name resolution for GNU Name Service Switch
 License:         LGPLv2+
 URL:             https://github.com/lathiat/nss-mdns
@@ -18,31 +18,43 @@ common Unix/Linux programs in the ad-hoc mDNS domain .local.
 %package_help
 
 %prep
-%autosetup
+%autosetup -n %{name}-%{version}
 
 %build
 %configure --libdir=/%{_lib}
 %make_build
 
+%install
+%make_install
+
 %check
 make check || (cat ./test-suite.log; false)
 
-%install
-rm -rf $RPM_BUILD_ROOT
-%make_install
-
-%post
-%{?ldconfig}
-
-%posttrans
-authselect enable-feature with-mdns4 &> /dev/null || :
+%pre
 
 %preun
-authselect disable-feature with-mdns4 &> /dev/null || :
+if [ "$1" -eq 0 -a -f /etc/nsswitch.conf ] ; then
+	sed -i.bak '
+		/^hosts:/ !b
+		s/[[:blank:]]\+mdns\(4\|6\)\?\(_minimal\( \[NOTFOUND=return\]\)\?\)\?//g
+	' /etc/nsswitch.conf
+fi
 
-%ldconfig_postun
+%post
+/sbin/ldconfig
+if [ -f /etc/nsswitch.conf ] ; then
+	sed -i.bak '
+		/^hosts:/ !b
+		/\<mdns\(4\|6\)\?\(_minimal\)\?\>/ b
+		s/\([[:blank:]]\+\)dns\>/\1mdns4_minimal [NOTFOUND=return] dns/g
+		' /etc/nsswitch.conf
+fi
+
+%postun
+/sbin/ldconfig
 
 %files
+%defattr(-,root,root)
 %license LICENSE
 /%{_lib}/*.so.*
 
@@ -50,8 +62,11 @@ authselect disable-feature with-mdns4 &> /dev/null || :
 %doc README.md NEWS.md ACKNOWLEDGEMENTS.md
 
 %changelog
+* Wed Mar 02 2022 wulei <wulei80@huawei.com> - 0.15.1-3
+- Add preun and post
+
 * Fri Jan 07 2022 wulei <wulei80@huawei.com> - 0.15.1-2
-- add help package
+- Add help package
 
 * Tue Dec 28 2021 wulei <wulei80@huawei.com> - 0.15.1-1
 - Package update