rpm: Generate per distribution and multilib macro files

index 3930410..96e46f3 100644
@@ -115,6 +115,9 @@ inherit autotools gettext
 
 acpaths = "-I ${S}/db/dist/aclocal -I ${S}/db/dist/aclocal_java"
 
+# The local distribution macro directory
+distromacrodir = "${libdir}/rpm/poky"
+
 # Specify the default rpm macros in terms of adjustable variables
 rpm_macros = "%{_usrlibrpm}/macros:%{_usrlibrpm}/${DISTRO}/macros:%{_usrlibrpm}/${DISTRO}/%{_target}/macros:%{_etcrpm}/macros.*:%{_etcrpm}/macros:%{_etcrpm}/%{_target}/macros:~/.oerpmmacros"
 rpm_macros_class-native = "%{_usrlibrpm}/macros:%{_usrlibrpm}/${DISTRO}/macros:%{_usrlibrpm}/${DISTRO}/%{_target}/macros:~/.oerpmmacros"

@@ -339,6 +342,7 @@ FILES_${PN}-build = "${prefix}/src/rpm \
 		${libdir}/rpm/vpkg-provides.sh \
 		${libdir}/rpm/vpkg-provides2.sh \
 		${libdir}/rpm/perfile_rpmdeps.sh \
+		${distromacrodir} \
 		"
 RDEPENDS_${PN} = "base-files run-postinsts"
 RDEPENDS_${PN}_class-native = ""

@@ -479,6 +483,83 @@ do_install_append() {
 
 }
 
+do_install_append_class-target() {
+	# Create and install distribution specific macros
+	mkdir -p ${D}/${distromacrodir}
+	cat << EOF > ${D}/${distromacrodir}/macros
+%_defaultdocdir		${docdir}
+
+%_prefix                ${prefix}
+%_exec_prefix           ${exec_prefix}
+%_datarootdir           ${datadir}
+%_bindir                ${bindir}
+%_sbindir               ${sbindir}
+%_libexecdir            %{_libdir}/%{name}
+%_datadir               ${datadir}
+%_sysconfdir            ${sysconfdir}
+%_sharedstatedir        ${sharedstatedir}
+%_localstatedir         ${localstatedir}
+%_lib                   lib
+%_libdir                %{_exec_prefix}/%{_lib}
+%_includedir            ${includedir}
+%_oldincludedir         ${oldincludedir}
+%_infodir               ${infodir}
+%_mandir                ${mandir}
+%_localedir             %{_libdir}/locale
+EOF
+
+	# Create and install multilib specific macros
+	${@multilib_rpmmacros(d)}
+}
+
+def multilib_rpmmacros(d):
+    localdata = d.createCopy()
+    # We need to clear the TOOLCHAIN_OPTIONS (--sysroot)
+    localdata.delVar('TOOLCHAIN_OPTIONS')
+
+    # Set 'localdata' values to be consistent with 'd' values.
+    localdata.setVar('distromacrodir', d.getVar('distromacrodir', True))
+    localdata.setVar('WORKDIR', d.getVar('WORKDIR', True))
+
+    ret = gen_arch_macro(localdata)
+
+    variants = d.getVar("MULTILIB_VARIANTS", True) or ""
+    for item in variants.split():
+        # Load overrides from 'd' to avoid having to reset the value...
+        localdata = d.createCopy()
+        overrides = d.getVar("OVERRIDES", False) + ":virtclass-multilib-" + item
+        localdata.setVar("OVERRIDES", overrides)
+        localdata.setVar("MLPREFIX", item + "-")
+        bb.data.update_data(localdata)
+        ret += gen_arch_macro(localdata)
+    return ret
+
+def gen_arch_macro(d):
+    # Generate shell script to produce the file as part of do_install
+    val  = "mkdir -p ${D}/${distromacrodir}/${TARGET_ARCH}-${TARGET_OS}\n"
+    val += "cat << EOF > ${D}/${distromacrodir}/${TARGET_ARCH}-${TARGET_OS}/macros\n"
+    val += "%_lib               ${baselib}\n"
+    val += "%_libdir            ${libdir}\n"
+    val += "%_localedir         ${localedir}\n"
+    val += "\n"
+    val += "# Toolchain configuration\n"
+    val += "%TOOLCHAIN_OPTIONS  %{nil}\n"
+    val += "%__ar               ${@d.getVar('AR', True).replace('$','%')}\n"
+    val += "%__as               ${@d.getVar('AS', True).replace('$','%')}\n"
+    val += "%__cc               ${@d.getVar('CC', True).replace('$','%')}\n"
+    val += "%__cpp              ${@d.getVar('CPP', True).replace('$','%')}\n"
+    val += "%__cxx              ${@d.getVar('CXX', True).replace('$','%')}\n"
+    val += "%__ld               ${@d.getVar('LD', True).replace('$','%')}\n"
+    val += "%__nm               ${@d.getVar('NM', True).replace('$','%')}\n"
+    val += "%__objcopy          ${@d.getVar('OBJCOPY', True).replace('$','%')}\n"
+    val += "%__objdump          ${@d.getVar('OBJDUMP', True).replace('$','%')}\n"
+    val += "%__ranlib           ${@d.getVar('RANLIB', True).replace('$','%')}\n"
+    val += "%__strip            ${@d.getVar('STRIP', True).replace('$','%')}\n"
+    val += "EOF\n"
+    val += "\n"
+    return d.expand(val)
+
+
 add_native_wrapper() {
         create_wrapper ${D}/${bindir}/rpm \
 		RPM_USRLIBRPM='`dirname $''realpath`'/${@os.path.relpath(d.getVar('libdir', True), d.getVar('bindir', True))}/rpm \