build/make: return to make from top directory

It looks like, there is not so much that needs to be fixed for
building criu from a top directory.
After the patch it's possible to do `make criu/mount.o` i.e.
It will build protobuf, compel as dependencies (if they are not built),
but no more from criu objects. If something breaks, you can
do make from vim and jump to error. Nice.
Mostly the patch corrects pathes to objects - I tried to make them
depend on $(obj) or $(SRC_DIR)/criu, where it's possible.

After it tested:
`make -j 10`, `make criu/log.o`, `make clean`, `make mrproper`,
`make install DESTDIR=/tmp/criu`, `make uninstall DESTDIR=/tmp/criu`

Note: I improperly called v1 for this patch as "return to make from
top Makefile" -- but I didn't mean that (and it was friday ;)

This patch doesn't yet switch to top-Makefile building, but that's
a step in that way (building from a top Makefile needs correct pathes
in makefiles) which also adds ability to build objects in subdirectories
and etc.

Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Makefile

@@ -179,6 +179,8 @@ endif
 # on anything else.
 $(eval $(call gen-built-in,images))
 
+.PHONY: .FORCE
+
 #
 # CRIU building done in own directory
 # with slightly different rules so we
@@ -187,17 +189,17 @@ $(eval $(call gen-built-in,images))
 #
 # But note that we're already included
 # the nmk so we can reuse it there.
-criu/%: images/built-in.o $(VERSION_HEADER)
-	$(Q) $(MAKE) -C criu $@
+criu/%: images/built-in.o $(VERSION_HEADER) .FORCE
+	$(Q) $(MAKE) $(build)=criu $@
 criu: images/built-in.o $(VERSION_HEADER)
-	$(Q) $(MAKE) -C criu all
+	$(Q) $(MAKE) $(build)=criu all
 .PHONY: criu
 
 #
 # Libraries next once criu it ready
 # (we might generate headers and such
 # when building criu itself).
-lib/%: criu
+lib/%: criu .FORCE
 	$(Q) $(MAKE) -C lib $@
 lib: criu
 	$(Q) $(MAKE) -C lib all
@@ -215,13 +217,13 @@ subclean:
 
 clean: subclean
 	$(Q) $(MAKE) $(build)=images $@
-	$(Q) $(MAKE) -C criu $@
+	$(Q) $(MAKE) $(build)=criu $@
 .PHONY: clean
 
 # mrproper depends on clean in nmk
 mrproper: subclean
 	$(Q) $(MAKE) $(build)=images $@
-	$(Q) $(MAKE) -C criu $@
+	$(Q) $(MAKE) $(build)=criu $@
 	$(Q) $(RM) $(VERSION_HEADER)
 	$(Q) $(RM) cscope.*
 	$(Q) $(RM) tags TAGS

Makefile.install

@@ -43,7 +43,7 @@ install-lib: lib
 .PHONY: install-lib
 
 install-criu: criu
-	$(Q) $(MAKE) -C criu install
+	$(Q) $(MAKE) $(build)=criu install
 .PHONY: install-criu
 
 install: install-man install-lib install-criu

criu/Makefile

@@ -2,8 +2,9 @@
 # 6a8d90f5fec4 "attr: Allow attribute type 0" 
 WRAPFLAGS		+= -Wl,--wrap=nla_parse,--wrap=nlmsg_parse
 
-ARCH_DIR		:= arch/$(SRCARCH)
-export ARCH_DIR
+ARCH_DIR		:= criu/arch/$(SRCARCH)
+PIE_DIR			:= criu/pie
+export ARCH_DIR PIE_DIR
 
 #
 # General flags.
@@ -11,8 +12,8 @@ ccflags-y		+= -fno-strict-aliasing
 ccflags-y		+= -iquote $(SRC_DIR)/criu/include
 ccflags-y		+= -iquote $(SRC_DIR)/images
 ccflags-y		+= -iquote $(SRC_DIR)/criu/pie
-ccflags-y		+= -iquote $(SRC_DIR)/criu/$(ARCH_DIR)
-ccflags-y		+= -iquote $(SRC_DIR)/criu/$(ARCH_DIR)/include
+ccflags-y		+= -iquote $(SRC_DIR)/$(ARCH_DIR)
+ccflags-y		+= -iquote $(SRC_DIR)/$(ARCH_DIR)/include
 ccflags-y		+= -iquote $(SRC_DIR)/
 ccflags-y		+= -I/usr/include/libnl3
 
@@ -38,11 +39,14 @@ include $(__nmk_dir)/msg.mk
 
 #
 # Needed libraries checks
-include Makefile.packages
+include $(SRC_DIR)/criu/Makefile.packages
 
 #
 # Configure variables.
-include Makefile.config
+CONFIG_HEADER := $(obj)/include/config.h
+ifneq ($(filter-out clean mrproper,$(MAKECMDGOALS)),)
+include $(SRC_DIR)/criu/Makefile.config
+endif
 config: $(VERSION_HEADER)
 
 #
@@ -55,84 +59,84 @@ syscalls_lib: config
 #
 # Architecture dependant part.
 ARCH-LIB		:= $(ARCH_DIR)/crtools.built-in.o
-arch_lib: syscalls_lib
-	$(Q) $(MAKE) $(call build-as,Makefile,$(ARCH_DIR)) all
-.PHONY: arch_lib
+$(ARCH-LIB): syscalls_lib
+	$(Q) $(MAKE) $(build)=$(ARCH_DIR) all
 
 #
 # piegen tool needed for PIE code.
 ifeq ($(piegen-y),y)
-piegen-bin		:= pie/piegen/piegen
+piegen-bin		:= criu/pie/piegen/piegen
 
-pie/piegen/%: config
-	$(Q) CC=$(HOSTCC) LD=$(HOSTLD) CFLAGS="$(ccflags-y) $(HOSTCFLAGS) $(WARNINGS) $(DEFINES)" $(MAKE) $(build)=pie/piegen $@
-$(piegen-bin): pie/piegen/built-in.o
+criu/pie/piegen/%: config
+	$(Q) CC=$(HOSTCC) LD=$(HOSTLD) CFLAGS="$(ccflags-y) $(HOSTCFLAGS) $(WARNINGS) $(DEFINES)" $(MAKE) $(build)=criu/pie/piegen $@
+$(piegen-bin): criu/pie/piegen/built-in.o
 	$(call msg-link, $@)
 	$(Q) $(HOSTCC) $(HOSTCFLAGS) $^ $(LDFLAGS) -o $@
 endif
 
 #
 # PIE library code.
-pie/lib.a: arch_lib
-	$(Q) $(MAKE) $(call build-as,Makefile.library,pie) all
+criu/pie/lib.a: $(ARCH-LIB)
+	$(Q) $(MAKE) $(call build-as,Makefile.library,criu/pie) all
 
 #
 # PIE code blobs themseves.
-pie: $(piegen-bin) pie/lib.a
-	$(Q) $(MAKE) $(build)=pie all
+pie: $(piegen-bin) criu/pie/lib.a
+	$(Q) $(MAKE) $(build)=criu/pie all
 .PHONY: pie
 
 #
 # CRIU executable
-PROGRAM-BUILTINS	+= ../images/built-in.o
-PROGRAM-BUILTINS	+= built-in.o
-PROGRAM-BUILTINS	+= pie/lib.a
+PROGRAM-BUILTINS	+= criu/pie/lib.a
+PROGRAM-BUILTINS	+= images/built-in.o
+PROGRAM-BUILTINS	+= $(obj)/built-in.o
+PROGRAM-BUILTINS	+= $(ARCH-LIB)
 
-built-in.o: pie
-	$(Q) $(MAKE) $(call build-as,Makefile.crtools,.) all
+$(obj)/built-in.o: pie
+	$(Q) $(MAKE) $(call build-as,Makefile.crtools,criu) all
 
-criu: $(PROGRAM-BUILTINS)
+$(obj)/criu: $(PROGRAM-BUILTINS)
 	$(call msg-link, $@)
-	$(Q) $(CC) $(CFLAGS) $^ $(ARCH-LIB) $(LIBS) $(WRAPFLAGS) $(LDFLAGS) $(GMONLDOPT) -rdynamic -o $@
-
+	$(Q) $(CC) $(CFLAGS) $^ $(LIBS) $(WRAPFLAGS) $(LDFLAGS) $(GMONLDOPT) -rdynamic -o $@
 
-subclean:
-	$(Q) $(RM) ./*.{gcda,gcno,gcov}
-	$(Q) $(RM) ./pie/*.{gcda,gcno,gcov}
-	$(Q) $(RM) ./pie/piegen/*.{gcda,gcno,gcov}
-	$(Q) $(RM) -r ./gcov
-	$(Q) $(RM) criu
-.PHONY: subclean
 
 #
 # Clean the most, except generated c files
+subclean:
+	$(Q) $(RM) $(obj)/*.{gcda,gcno,gcov}
+	$(Q) $(RM) $(obj)/pie/*.{gcda,gcno,gcov}
+	$(Q) $(RM) $(obj)/pie/piegen/*.{gcda,gcno,gcov}
+	$(Q) $(RM) -r $(obj)/gcov
+	$(Q) $(MAKE) $(call build-as,Makefile.syscalls,$(ARCH_DIR)) clean
+	$(Q) $(MAKE) $(build)=$(ARCH_DIR) clean
+	$(Q) $(MAKE) $(call build-as,Makefile.library,$(PIE_DIR)) clean
+	$(Q) $(MAKE) $(call build-as,Makefile.crtools,criu) clean
+	$(Q) $(MAKE) $(build)=$(PIE_DIR) clean
+	$(Q) $(MAKE) $(build)=$(PIE_DIR)/piegen clean
+.PHONY: subclean
+cleanup-y      += $(obj)/criu
 clean: subclean
-	$(Q) $(MAKE) $(call build-as,Makefile.syscalls,$(ARCH_DIR)) $@
-	$(Q) $(MAKE) $(call build-as,Makefile,$(ARCH_DIR)) $@
-	$(Q) $(MAKE) $(call build-as,Makefile.library,pie) $@
-	$(Q) $(MAKE) $(call build-as,Makefile.crtools,.) $@
-	$(Q) $(MAKE) $(build)=pie/piegen $@
-	$(Q) $(MAKE) $(build)=pie $@
-.PHONY: clean
 
 #
 # Delete all generated files
-mrproper: subclean
-	$(Q) $(MAKE) $(call build-as,Makefile.syscalls,$(ARCH_DIR)) $@
-	$(Q) $(MAKE) $(call build-as,Makefile,$(ARCH_DIR)) $@
-	$(Q) $(MAKE) $(call build-as,Makefile.library,pie) $@
-	$(Q) $(MAKE) $(call build-as,Makefile.crtools,.) $@
-	$(Q) $(MAKE) $(build)=pie/piegen $@
-	$(Q) $(MAKE) $(build)=pie $@
-	$(Q) $(RM) $(CONFIG_HEADER)
-.PHONY: mrproper
-
-UAPI_HEADERS := include/criu-plugin.h include/criu-log.h
-
-install: criu
-	$(E) "  INSTALL " criu
+subproper:
+	$(Q) $(MAKE) $(call build-as,Makefile.syscalls,$(ARCH_DIR)) mrproper
+	$(Q) $(MAKE) $(build)=$(ARCH_DIR) mrproper
+	$(Q) $(MAKE) $(call build-as,Makefile.library,$(PIE_DIR)) mrproper
+	$(Q) $(MAKE) $(call build-as,Makefile.crtools,criu) mrproper
+	$(Q) $(MAKE) $(build)=$(PIE_DIR) mrproper
+	$(Q) $(MAKE) $(build)=$(PIE_DIR)/piegen mrproper
+.PHONY: subproper
+mrproper-y     += $(CONFIG_HEADER)
+mrproper: subproper
+
+UAPI_HEADERS := $(SRC_DIR)/criu/include/criu-plugin.h
+UAPI_HEADERS += $(SRC_DIR)/criu/include/criu-log.h
+
+install: $(obj)/criu
+	$(E) "  INSTALL " $(obj)/criu
 	$(Q) mkdir -p $(DESTDIR)$(SBINDIR)
-	$(Q) install -m 755 criu $(DESTDIR)$(SBINDIR)
+	$(Q) install -m 755 $(obj)/criu $(DESTDIR)$(SBINDIR)
 	$(Q) mkdir -p $(DESTDIR)$(INCLUDEDIR)
 	$(Q) install -m 644 $(UAPI_HEADERS) $(DESTDIR)$(INCLUDEDIR)
 	$(Q) mkdir -p $(DESTDIR)$(LIBEXECDIR)/criu/scripts
@@ -146,8 +150,4 @@ uninstall:
 	$(Q) $(RM) $(addprefix $(DESTDIR)$(LIBEXECDIR)/criu/scripts/,systemd-autofs-restart.sh)
 .PHONY: uninstall
 
-#
-# Final @all target.
-all: check-packages criu
-	@true
-.PHONY: all
+all-y += check-packages $(obj)/criu

criu/Makefile.config

 include $(__nmk_dir)/utils.mk
 include $(__nmk_dir)msg.mk
-include ../scripts/feature-tests.mak
-
-CONFIG_HEADER := include/config.h
+include $(SRC_DIR)/scripts/feature-tests.mak
 
 ifeq ($(call try-cc,$(FEATURE_TEST_LIBBSD_DEV),-lbsd),y)
         LIBS	+= -lbsd
@@ -26,7 +24,7 @@ endif
 endef
 
 define config-header-rule
-$(CONFIG_HEADER): include/config-base.h
+$(CONFIG_HEADER): $(obj)/include/config-base.h
 	$$(call msg-gen, $$@)
 	$(Q) @echo '#ifndef __CR_CONFIG_H__'				> $$@
 	$(Q) @echo '#define __CR_CONFIG_H__'				>> $$@
@@ -47,6 +45,6 @@ endef
 
 $(eval $(config-header-rule))
 
-$(CONFIG_HEADER): ../scripts/feature-tests.mak
+$(CONFIG_HEADER): $(SRC_DIR)/scripts/feature-tests.mak
 config: $(CONFIG_HEADER)
 .PHONY: config

criu/Makefile.crtools

-ccflags-y		+= -iquote $(ARCH)
+ccflags-y		+= -iquote criu/$(ARCH)
 ccflags-y		+= $(DEFINES)
 obj-y			+= action-scripts.o
 obj-y			+= aio.o
@@ -86,10 +86,10 @@ endif
 
 PROTOBUF_GEN := $(SRC_DIR)/scripts/protobuf-gen.sh
 
-protobuf-desc.c: protobuf-desc-gen.h
+$(obj)/protobuf-desc.d: $(obj)/protobuf-desc-gen.h
 
-protobuf-desc-gen.h: $(PROTOBUF_GEN) include/protobuf-desc.h
+$(obj)/protobuf-desc-gen.h: $(PROTOBUF_GEN) criu/include/protobuf-desc.h
 	$(call msg-gen, $@)
 	$(Q) $(SH) $(PROTOBUF_GEN) > $@
 
-mrproper-y += protobuf-desc-gen.h
+mrproper-y += $(obj)/protobuf-desc-gen.h

criu/Makefile.packages

@@ -38,5 +38,6 @@ check-packages-failed:
 	$(error Compilation aborted)
 
 check-packages:
-	$(Q) $(MAKE) check-build-packages || $(MAKE) check-packages-failed
+	$(Q) $(MAKE) -f $(obj)/Makefile.packages check-build-packages || \
+		$(MAKE) -f $(obj)/Makefile.packages check-packages-failed
 .PHONY: check-build-packages check-packages-failed check-packages

criu/pie/Makefile

@@ -15,7 +15,12 @@ restorer-obj-e		+= ./$(ARCH_DIR)/syscalls.built-in.o
 # applications, which is not the target of the
 # project.
 #
-CFLAGS			:= $(filter-out -pg $(CFLAGS-GCOV),$(CFLAGS)) -iquote pie/piegen -iquote arch/$(ARCH)/include -iquote $(SRC_DIR) -iquote $(SRC_DIR)/criu/include
+CFLAGS			:= $(filter-out -pg $(CFLAGS-GCOV),$(CFLAGS))
+CFLAGS			+= -iquote $(SRC_DIR)/criu/pie/piegen
+CFLAGS			+= -iquote $(SRC_DIR)/criu/arch/$(ARCH)/include
+CFLAGS			+= -iquote $(SRC_DIR)/criu/include
+CFLAGS			+= -iquote $(SRC_DIR)
+
 
 ifneq ($(filter-out ia32,$(ARCH)),)
         ccflags-y	+= -DCR_NOGLIBC -fpie -Wa,--noexecstack -fno-stack-protector
@@ -37,7 +42,7 @@ PIELDS			:= pie.lds.S
 .SECONDARY:
 
 ifeq ($(piegen-y),y)
-target-name = $(patsubst pie/%-blob.h,%,$(1))
+target-name = $(patsubst criu/pie/%-blob.h,%,$(1))
 
 ifeq ($(SRCARCH),ppc64)
 $(obj)/$(PIELDS): $(obj)/pie-reloc.lds.S.in
@@ -68,9 +73,9 @@ $(obj)/%.built-in.bin.o: $(obj)/%.built-in.o $(obj)/lib.a $(obj)/$(PIELDS)
 	$(call msg-gen, $@)
 	$(Q) $(LD) -r -T $(obj)/$(PIELDS) -o $@ $< $(obj)/lib.a
 
-$(obj)/%-blob.h: $(obj)/%.built-in.bin.o $(obj)/$(PIELDS) pie/piegen
+$(obj)/%-blob.h: $(obj)/%.built-in.bin.o $(obj)/$(PIELDS) criu/pie/piegen
 	$(call msg-gen, $@)
-	$(Q) pie/piegen/piegen -f $< -v $(call target-name,$@)_relocs -p $(call target-name,$@)_blob_offset__ -s $(call target-name,$@)_blob -o $@ $(piegen_stdout)
+	$(Q) criu/pie/piegen/piegen -f $< -v $(call target-name,$@)_relocs -p $(call target-name,$@)_blob_offset__ -s $(call target-name,$@)_blob -o $@ $(piegen_stdout)
 
 else
 

criu/pie/Makefile.library

@@ -28,7 +28,9 @@ endif
 # applications, which is not the target of the
 # project.
 #
-iquotes			:= -iquote pie/piegen -iquote arch/$(ARCH)/include -iquote $(SRC_DIR) -iquote $(SRC_DIR)/criu/include
+iquotes			:= -iquote $(SRC_DIR)/$(PIE_DIR)/piegen
+iquotes			+= -iquote $(SRC_DIR)/$(ARCH_DIR)/include
+iquotes			+= -iquote $(SRC_DIR) -iquote $(SRC_DIR)/criu/include
 CFLAGS			:= $(filter-out -pg $(CFLAGS-GCOV),$(CFLAGS)) $(iquotes)
 asflags-y		:= -D__ASSEMBLY__ $(iquotes)
 

scripts/protobuf-gen.sh

@@ -5,7 +5,7 @@ for x in $(sed -n '/PB_AUTOGEN_START/,/PB_AUTOGEN_STOP/ {
 		s/,.*$//;
 		s/\tPB_//;
 		p;
-	   }' include/protobuf-desc.h); do
+	   }' criu/include/protobuf-desc.h); do
 	x_la=$(echo $x | sed $TR)
 	x_uf=$(echo $x | sed -nr 's/^./&#\\\
 /;