improvement of rpm generation

mrw-c++.spec.in

@@ -7,34 +7,16 @@ Group: Development/Libraries/C++
 
 Source0: %{name}-%{version}.tar.gz
 BuildRoot: %{_tmppath}/%{name}-%{version}-%{release}-root
-BuildRequires: gnupg, expect, subversion, make, automake, autoconf, rpm-build, binutils-devel, gcc-c++, libtool, doxygen, java-openjdk  @RPM_BUILD_DEPEND@ @RPM_DEPEND_IFEXISTS@
-%if 0%{?fedora} != 20
-BuildRequires: graphviz
-%endif
-%if 0%{?fedora} || 0%{?rhel} || 0%{?rhl} || 0%{?centos} || 0%{?centos_ver} || 0%{?centos_version} || 0%{?mageia}
-BuildRequires: which, pkgconfig, cppunit-devel
-%if 0%{?rhel} > 6 || 0%{?rhl} > 6 || 0%{?centos} > 6 || 0%{?fedora} || 0%{?mageia}
-BuildRequires: rpm-sign
-%endif
-%if 0%{?mageia}
-BuildRequires: gnupg, lsb-release, libltdl-devel
+BuildRequires: which, pkgconfig, gnupg, expect, subversion, make, automake, autoconf, rpm-build, binutils-devel, gcc-c++, libtool, libtool-ltdl-devel, cppunit-devel, doxygen, graphviz, java-openjdk  @RPM_BUILD_DEPEND@ @RPM_DEPEND_IFEXISTS@
+
+#### os dependent definitions ####
+%if 0%{?suse_version} || 0%{?sles_version}
+BuildRequires: lsb-release
 %else
-BuildRequires: gpg, redhat-lsb, libtool-ltdl-devel
-%endif
-%if ! ( 0%{?centos} || 0%{?centos_ver} || 0%{?centos_version} )
+BuildRequires: rpm-sign, redhat-lsb
+%endif%if ! 0%{?centos}
 BuildRequires: mscgen
-
-%else
-
-%endif
-%else%if 0%{?suse_version} || 0%{?sles_version}
-BuildRequires: pkg-config, lsb-release, libcppunit-devel
-%if 0%{?suse_version} < 1200 ||  0%{?sles_version} < 1200
-
-%else
-
-%endif
-%endif%endif
+%fi
 
 %description
 @README@