* util/grub-mkconfig_lib.in (gettext_quoted): Add clarifying

comment.  Add an extra layer of quotation, requiring the output of
this function to be used in a printf format string.
(gettext_printf): New function.
* util/grub.d/10_hurd.in: Use gettext_printf where appropriate.
Extract translatable strings from here-documents and use a temporary
variable instead, so that xgettext can find them.
* util/grub.d/10_kfreebsd.in: Likewise.
* util/grub.d/10_linux.in: Likewise.
* util/grub.d/20_linux_xen.in: Likewise.

* po/grub.d.sed: New file.
* po/Makefile.in.in ($(DOMAIN).pot-update): Extract gettext_printf
arguments.  Set c-format flags on all strings extracted from
util/grub.d/ (xgettext refuses to include these itself for strings
it extracted from a shell file, but these really are c-format).

util/grub-mkconfig_lib.in

@@ -187,8 +187,20 @@ version_find_latest ()
   echo "$a"
 }
 
+# One layer of quotation is eaten by "", the second by sed, and the third by
+# printf; so this turns ' into \'.  Note that you must use the output of
+# this function in a printf format string.
 gettext_quoted () {
-  $gettext "$@" | sed "s/'/'\\\\''/g"
+  $gettext "$@" | sed "s/'/'\\\\\\\\''/g"
+}
+
+# Run the first argument through gettext_quoted, and then pass that and all
+# remaining arguments to printf.  This is a useful abbreviation and tends to
+# be easier to type.
+gettext_printf () {
+  local format="$1"
+  shift
+  printf "$(gettext_quoted "$format")" "$@"
 }
 
 uses_abstraction () {

util/grub.d/10_hurd.in

@@ -81,14 +81,16 @@ do
 menuentry "${OS} ${KERNEL}" ${CLASS} {
 EOF
   prepare_grub_to_access_device ${GRUB_DEVICE_BOOT} | sed -e "s/^/\t/"
+  message="$(gettext_printf "Loading GNU Mach ...")"
   cat << EOF
-	echo		'$(gettext_quoted "Loading GNU Mach ...")'
+	echo		'$message'
 	multiboot	${kernel} root=device:${GRUB_DEVICE#/dev/}
 EOF
   save_default_entry | sed -e "s/^/\t/"
   prepare_grub_to_access_device ${GRUB_DEVICE} | sed -e "s/^/\t/"
+  message="$(gettext_printf "Loading the Hurd ...")"
   cat << EOF
-	echo		'$(gettext_quoted "Loading the Hurd ...")'
+	echo		'$message'
 	module		/hurd/${hurd_fs}.static ${hurd_fs} --readonly \\
 			--multiboot-command-line='\${kernel-command-line}' \\
 			--host-priv-port='\${host-port}' \\
@@ -103,13 +105,15 @@ EOF
 menuentry "${OS} ${KERNEL} (recovery mode)" ${CLASS} {
 EOF
   prepare_grub_to_access_device ${GRUB_DEVICE_BOOT} | sed -e "s/^/\t/"
+  message="$(gettext_printf "Loading GNU Mach ...")"
   cat << EOF
-	echo		'$(gettext_quoted "Loading GNU Mach ...")'
+	echo		'$message'
 	multiboot	${kernel} root=device:${GRUB_DEVICE#/dev/} -s
 EOF
   prepare_grub_to_access_device ${GRUB_DEVICE} | sed -e "s/^/\t/"
+  message="$(gettext_printf "Loading the Hurd ...")"
   cat << EOF
-	echo		'$(gettext_quoted "Loading the Hurd ...")'
+	echo		'$message'
 	module		/hurd/${hurd_fs}.static ${hurd_fs} \\
 			--multiboot-command-line='\${kernel-command-line}' \\
 			--host-priv-port='\${host-port}' \\

util/grub.d/10_kfreebsd.in

@@ -84,8 +84,9 @@ kfreebsd_entry ()
   fi
 
   printf '%s\n' "${prepare_boot_cache}"
+  message="$(gettext_printf "Loading kernel of FreeBSD %s ..." ${version})"
   cat << EOF
-	echo			'$(printf "$(gettext_quoted "Loading kernel of FreeBSD %s ...")" ${version})'
+	echo			'$message'
 	kfreebsd		${rel_dirname}/${basename} ${args}
 EOF
 

util/grub.d/10_linux.in

@@ -94,13 +94,15 @@ EOF
     prepare_boot_cache="$(prepare_grub_to_access_device ${GRUB_DEVICE_BOOT} | sed -e "s/^/\t/")"
   fi
   printf '%s\n' "${prepare_boot_cache}"
+  message="$(gettext_printf "Loading Linux %s ..." ${version})"
   cat << EOF
-	echo	'$(printf "$(gettext_quoted "Loading Linux %s ...")" ${version})'
+	echo	'$message'
 	linux	${rel_dirname}/${basename} root=${linux_root_device_thisversion} ro ${args}
 EOF
   if test -n "${initrd}" ; then
+    message="$(gettext_printf "Loading initial ramdisk ...")"
     cat << EOF
-	echo	'$(gettext_quoted "Loading initial ramdisk ...")'
+	echo	'$message'
 	initrd	${rel_dirname}/${initrd}
 EOF
   fi

util/grub.d/20_linux_xen.in

@@ -73,14 +73,16 @@ linux_entry ()
     prepare_boot_cache="$(prepare_grub_to_access_device ${GRUB_DEVICE_BOOT} | sed -e "s/^/\t/")"
   fi
   printf '%s\n' "${prepare_boot_cache}"
+  message="$(gettext_printf "Loading Linux %s ..." ${version})"
   cat << EOF
-	echo	'$(printf "$(gettext_quoted "Loading Linux %s ...")" ${version})'
+	echo	'$message'
 	multiboot	${rel_xen_dirname}/${xen_basename} placeholder ${xen_args}
 	module	${rel_dirname}/${basename} placeholder root=${linux_root_device_thisversion} ro ${args}
 EOF
   if test -n "${initrd}" ; then
+    message="$(gettext_printf "Loading initial ramdisk ...")"
     cat << EOF
-	echo	'$(gettext_quoted "Loading initial ramdisk ...")'
+	echo	'$message'
 	module	${rel_dirname}/${initrd}
 EOF
   fi