Add a new "none" platform that only builds utilities

This makes it possible to build generally-useful utilities such as
grub-mount even if the rest of GRUB has not been ported to the target
CPU.

* configure.ac: Add "none" platform.  Default to it for unsupported
CPUs rather than stopping with a fatal error.  Don't downgrade
x86_64-none to i386.  Define COND_real_platform Automake conditional
if the platform is anything other than "none".  Don't do any include
directory linking for "none".
* Makefile.am: Skip building grub-core and all bootcheck targets if
!COND_real_platform.
* include/grub/time.h: Don't include <grub/cpu/time.h> if GRUB_UTIL
is defined.

ChangeLog

@@ -1,3 +1,17 @@
+2014-09-23  Colin Watson  <[email protected]>
+
+	Add a new "none" platform that only builds utilities
+
+	* configure.ac: Add "none" platform.  Default to it for unsupported
+	CPUs rather than stopping with a fatal error.  Don't downgrade
+	x86_64-none to i386.  Define COND_real_platform Automake conditional
+	if the platform is anything other than "none".  Don't do any include
+	directory linking for "none".
+	* Makefile.am: Skip building grub-core and all bootcheck targets if
+	!COND_real_platform.
+	* include/grub/time.h: Don't include <grub/cpu/time.h> if GRUB_UTIL
+	is defined.
+
 2014-09-22  Andrei Borzenkov <[email protected]>
 
 	Use grub_cpu_to_XXX_compile_time for constants.

Makefile.am

@@ -1,7 +1,11 @@
 AUTOMAKE_OPTIONS = subdir-objects -Wno-portability
 
 DEPDIR = .deps-util
-SUBDIRS = grub-core/gnulib . grub-core po docs util/bash-completion.d
+SUBDIRS = grub-core/gnulib .
+if COND_real_platform
+SUBDIRS += grub-core
+endif
+SUBDIRS += po docs util/bash-completion.d
 
 include $(top_srcdir)/conf/Makefile.common
 include $(top_srcdir)/conf/Makefile.extra-dist
@@ -132,6 +136,8 @@ nodist_platform_HEADERS = config.h
 pkgdata_DATA += grub-mkconfig_lib
 
 
+if COND_real_platform
+
 if COND_i386_coreboot
 QEMU32=qemu-system-i386
 endif
@@ -383,8 +389,6 @@ if COND_powerpc_ieee1275
 BOOTCHECKS = bootcheck-linux-ppc
 endif
 
-EXTRA_DIST += grub-core/tests/boot/kbsd.init-i386.S grub-core/tests/boot/kbsd.init-x86_64.S grub-core/tests/boot/kbsd.spec.txt grub-core/tests/boot/kernel-8086.S grub-core/tests/boot/kernel-i386.S grub-core/tests/boot/kfreebsd-aout.cfg grub-core/tests/boot/kfreebsd.cfg grub-core/tests/boot/kfreebsd.init-i386.S grub-core/tests/boot/kfreebsd.init-x86_64.S grub-core/tests/boot/knetbsd.cfg grub-core/tests/boot/kopenbsd.cfg grub-core/tests/boot/kopenbsdlabel.txt grub-core/tests/boot/linux16.cfg grub-core/tests/boot/linux.cfg grub-core/tests/boot/linux.init-i386.S grub-core/tests/boot/linux.init-mips.S grub-core/tests/boot/linux.init-ppc.S grub-core/tests/boot/linux.init-x86_64.S grub-core/tests/boot/linux-ppc.cfg grub-core/tests/boot/multiboot2.cfg grub-core/tests/boot/multiboot.cfg grub-core/tests/boot/ntldr.cfg grub-core/tests/boot/pc-chainloader.cfg grub-core/tests/boot/qemu-shutdown-x86.S
-
 .PHONY: bootcheck-linux-i386 bootcheck-linux-x86_64 \
        bootcheck-kfreebsd-i386 bootcheck-kfreebsd-x86_64 \
        bootcheck-knetbsd-i386 bootcheck-knetbsd-x86_64 \
@@ -402,6 +406,10 @@ default_payload.elf: grub-mkstandalone grub-mkimage
 	pkgdatadir=. ./grub-mkstandalone --grub-mkimage=./grub-mkimage -O i386-coreboot -o $@ --modules='ahci pata ehci uhci ohci usb_keyboard usbms part_msdos xfs ext2 fat at_keyboard part_gpt usbserial_usbdebug cbfs' --install-modules='ls linux search configfile normal cbtime cbls memrw iorw minicmd lsmmap lspci halt reboot hexdump pcidump regexp setpci lsacpi chain test serial multiboot cbmemc linux16 gzio echo help' --fonts= --themes= --locales= -d grub-core/ /boot/grub/grub.cfg=$(srcdir)/coreboot.cfg
 endif
 
+endif
+
+EXTRA_DIST += grub-core/tests/boot/kbsd.init-i386.S grub-core/tests/boot/kbsd.init-x86_64.S grub-core/tests/boot/kbsd.spec.txt grub-core/tests/boot/kernel-8086.S grub-core/tests/boot/kernel-i386.S grub-core/tests/boot/kfreebsd-aout.cfg grub-core/tests/boot/kfreebsd.cfg grub-core/tests/boot/kfreebsd.init-i386.S grub-core/tests/boot/kfreebsd.init-x86_64.S grub-core/tests/boot/knetbsd.cfg grub-core/tests/boot/kopenbsd.cfg grub-core/tests/boot/kopenbsdlabel.txt grub-core/tests/boot/linux16.cfg grub-core/tests/boot/linux.cfg grub-core/tests/boot/linux.init-i386.S grub-core/tests/boot/linux.init-mips.S grub-core/tests/boot/linux.init-ppc.S grub-core/tests/boot/linux.init-x86_64.S grub-core/tests/boot/linux-ppc.cfg grub-core/tests/boot/multiboot2.cfg grub-core/tests/boot/multiboot.cfg grub-core/tests/boot/ntldr.cfg grub-core/tests/boot/pc-chainloader.cfg grub-core/tests/boot/qemu-shutdown-x86.S
+
 windowsdir=$(top_builddir)/$(PACKAGE)-$(VERSION)-for-windows
 windowsdir: $(PROGRAMS) $(starfield_DATA) $(platform_DATA)
 	test -d $(windowsdir) && rm -rf $(windowsdir) || true

configure.ac

@@ -125,7 +125,10 @@ if test "x$with_platform" = x; then
     ia64-*) platform=efi ;;
     arm-*) platform=uboot ;;
     arm64-*) platform=efi ;;
-    *) AC_MSG_ERROR([unsupported CPU: "$target_cpu"]) ;;
+    *)
+      AC_MSG_WARN([unsupported CPU: "$target_cpu" - only building utilities])
+      platform=none
+      ;;
   esac
 else
   platform="$with_platform"
@@ -135,6 +138,7 @@ case "$target_cpu"-"$platform" in
   x86_64-efi) ;;
   x86_64-emu) ;;
   x86_64-xen) ;;
+  x86_64-none) ;;
   x86_64-*) target_cpu=i386 ;;
   powerpc64-ieee1275) target_cpu=powerpc ;;
 esac
@@ -167,6 +171,7 @@ case "$target_cpu"-"$platform" in
   arm-efi) ;;
   arm64-efi) ;;
   *-emu) ;;
+  *-none) ;;
   *) AC_MSG_ERROR([platform "$platform" is not supported for target CPU "$target_cpu"]) ;;
 esac
 
@@ -1653,6 +1658,7 @@ AC_SUBST(BUILD_LIBM)
 # Automake conditionals
 #
 
+AM_CONDITIONAL([COND_real_platform], [test x$platform != xnone])
 AM_CONDITIONAL([COND_emu], [test x$platform = xemu])
 AM_CONDITIONAL([COND_clang], [test x$grub_cv_cc_target_clang = xyes])
 AM_CONDITIONAL([COND_i386_pc], [test x$target_cpu = xi386 -a x$platform = xpc])
@@ -1726,24 +1732,30 @@ AC_DEFINE_UNQUOTED(GRUB_SYSCONFDIR, "$grub_sysconfdir", [Configuration dir])
 
 
 # Output files.
-cpudir="${target_cpu}"
-if test x${cpudir} = xmipsel; then
-  cpudir=mips;
-fi
-grub_CHECK_LINK_DIR
-if test x"$link_dir" = xyes ; then
-  AC_CONFIG_LINKS([include/grub/cpu:include/grub/$cpudir])
-  if test "$platform" != emu ; then
-    AC_CONFIG_LINKS([include/grub/machine:include/grub/$cpudir/$platform])
+if test "$platform" != none; then
+  cpudir="${target_cpu}"
+  if test x${cpudir} = xmipsel; then
+    cpudir=mips;
   fi
-else
-  mkdir -p include/grub 2>/dev/null
-  rm -rf include/grub/cpu
-  cp -rp $srcdir/include/grub/$cpudir include/grub/cpu 2>/dev/null
-  if test "$platform" != emu ; then
-    rm -rf include/grub/machine
-    cp -rp $srcdir/include/grub/$cpudir/$platform include/grub/machine 2>/dev/null
+  grub_CHECK_LINK_DIR
+  if test x"$link_dir" = xyes ; then
+    AC_CONFIG_LINKS([include/grub/cpu:include/grub/$cpudir])
+    if test "$platform" != emu ; then
+      AC_CONFIG_LINKS([include/grub/machine:include/grub/$cpudir/$platform])
+    fi
+  else
+    mkdir -p include/grub 2>/dev/null
+    rm -rf include/grub/cpu
+    cp -rp $srcdir/include/grub/$cpudir include/grub/cpu 2>/dev/null
+    if test "$platform" != emu ; then
+      rm -rf include/grub/machine
+      cp -rp $srcdir/include/grub/$cpudir/$platform include/grub/machine 2>/dev/null
+    fi
   fi
+else
+  # Just enough to stop the compiler failing with -I$(srcdir)/include.
+  mkdir -p include 2>/dev/null
+  rm -rf include/grub
 fi
 
 AC_CONFIG_FILES([Makefile])

include/grub/time.h

@@ -21,7 +21,7 @@
 
 #include <grub/types.h>
 #include <grub/symbol.h>
-#ifndef GRUB_MACHINE_EMU
+#if !defined(GRUB_MACHINE_EMU) && !defined(GRUB_UTIL)
 #include <grub/cpu/time.h>
 #else
 static inline void