glibc: apply CoreOS tweaks

This time around our changes take a slightly different approach. Instead
of editing the ebuild to undo things done in the common eblit code the
eblits are edited directly, allowing for better customization. Also,
managing locales is now different. Inside the SDK all locales are built
at compile time, avoiding the need for locale-gen which is slow and
complicates setup of the SDK chroot. For cross-compiled targets (CoreOS
itself) final images don't include locale info either, again no need for
locale-gen.

The SDK is a bit bigger now, the compressed tarball is 20MB bigger and
200MB bigger extracted on disk. Considering how big it already is this
shouldn't be that big of a deal.

sdk_container/src/third_party/coreos-overlay/sys-libs/glibc/files/eblits/pkg_postinst.eblit

@@ -16,12 +16,6 @@ eblit-glibc-pkg_postinst() {
 		# errors from this step #253697
 		/sbin/telinit U 2>/dev/null
 
-		# if the host locales.gen contains no entries, we'll install everything
-		local locale_list="${ROOT}etc/locale.gen"
-		if [[ -z $(locale-gen --list --config "${locale_list}") ]] ; then
-			ewarn "Generating all locales; edit /etc/locale.gen to save time/space"
-			locale_list="${ROOT}usr/share/i18n/SUPPORTED"
-		fi
-		locale-gen -j $(makeopts_jobs) --config "${locale_list}"
+		## COREOS: locale-gen is not installed
 	fi
 }

sdk_container/src/third_party/coreos-overlay/sys-libs/glibc/files/eblits/pkg_preinst.eblit

@@ -46,11 +46,7 @@ eblit-glibc-pkg_preinst() {
 	# prepare /etc/ld.so.conf.d/ for files
 	mkdir -p "${EROOT}"/etc/ld.so.conf.d
 
-	# Default /etc/hosts.conf:multi to on for systems with small dbs.
-	if [[ $(wc -l < "${EROOT}"/etc/hosts) -lt 1000 ]] ; then
-		sed -i '/^multi off/s:off:on:' "${ED}"/etc/host.conf
-		elog "Defaulting /etc/host.conf:multi to on"
-	fi
+	## COREOS: host.conf is not installed
 
 	[[ ${ROOT} != "/" ]] && return 0
 	[[ -d ${D}/$(get_libdir) ]] || return 0

sdk_container/src/third_party/coreos-overlay/sys-libs/glibc/files/eblits/src_install.eblit

@@ -133,70 +133,40 @@ toolchain-glibc_src_install() {
 		return 0
 	fi
 
-	# Files for Debian-style locale updating
-	dodir /usr/share/i18n
-	sed \
-		-e "/^#/d" \
-		-e "/SUPPORTED-LOCALES=/d" \
-		-e "s: \\\\::g" -e "s:/: :g" \
-		"${S}"/localedata/SUPPORTED > "${ED}"/usr/share/i18n/SUPPORTED \
-		|| die "generating /usr/share/i18n/SUPPORTED failed"
-	cd "${WORKDIR}"/extra/locale
-	dosbin locale-gen || die
-	doman *.[0-8]
-	insinto /etc
-	doins locale.gen || die
+	## COREOS ##
+	# For reference, the rest of this function has been modified to do:
+	# - The SDK just gets the full locale archive, no need for locale-gen.
+	# - CoreOS targets (which are cross compiled) don't get any locales.
+	# - Config files are installed by baselayout, not glibc.
+	# - Forget about nscd for now, we have the use flag off anyway.
+
+	if ! tc-is-cross-compiler ; then
+		emake install_root="${D}$(alt_prefix)" localedata/install-locales || die
+		# Sanity check the above command worked
+		[[ -f ${ED}/usr/$(get_libdir)/locale/locale-archive ]] || die
+	else
+		keepdir /usr/$(get_libdir)/locale
+	fi
 
 	# Make sure all the ABI's can find the locales and so we only
 	# have to generate one set
 	local a
-	keepdir /usr/$(get_libdir)/locale
 	for a in $(get_install_abis) ; do
 		if [[ ! -e ${ED}/usr/$(get_abi_LIBDIR ${a})/locale ]] ; then
 			dosym /usr/$(get_libdir)/locale /usr/$(get_abi_LIBDIR ${a})/locale
 		fi
 	done
 
-	cd "${S}"
-
-	# Install misc network config files
-	insinto /etc
-	doins nscd/nscd.conf posix/gai.conf nss/nsswitch.conf || die
-	doins "${WORKDIR}"/extra/etc/*.conf || die
-
-	if ! in_iuse nscd || use nscd ; then
-		doinitd "${WORKDIR}"/extra/etc/nscd || die
-
-		local nscd_args=(
-			-e "s:@PIDFILE@:$(strings "${ED}"/usr/sbin/nscd | grep nscd.pid):"
-		)
-		version_is_at_least 2.16 || nscd_args+=( -e 's: --foreground : :' )
-		sed -i "${nscd_args[@]}" "${ED}"/etc/init.d/nscd
-
-		# Newer versions of glibc include the nscd.service themselves.
-		# TODO: Drop the $FILESDIR copy once 2.19 goes stable.
-		if version_is_at_least 2.19 ; then
-			systemd_dounit nscd/nscd.service || die
-			systemd_newtmpfilesd nscd/nscd.tmpfiles nscd.conf || die
-		else
-			systemd_dounit "${FILESDIR}"/nscd.service || die
-			systemd_newtmpfilesd "${FILESDIR}"/nscd.tmpfilesd nscd.conf || die
-		fi
-	else
-		# Do this since extra/etc/*.conf above might have nscd.conf.
-		rm -f "${ED}"/etc/nscd.conf
-	fi
+	# Clean out any default configs
+	rm -rf "${ED}"/etc
 
 	echo 'LDPATH="include ld.so.conf.d/*.conf"' > "${T}"/00glibc
 	doenvd "${T}"/00glibc || die
 
+	cd "${S}"
 	for d in BUGS ChangeLog* CONFORMANCE FAQ NEWS NOTES PROJECTS README* ; do
 		[[ -s ${d} ]] && dodoc ${d}
 	done
-
-	# Prevent overwriting of the /etc/localtime symlink.  We'll handle the
-	# creation of the "factory" symlink in pkg_postinst().
-	rm -f "${ED}"/etc/localtime
 }
 
 toolchain-glibc_headers_install() {