export LD       := i586-elf-ld
export CC       := i586-elf-gcc
export CXX      := i586-elf-g++
export OBJDUMP  := i586-elf-objdump
export NASM     := nasm

WD              := $(shell pwd)
export HOS_TOPLEVEL := $(WD)
LDSCRIPT        := link.ld
KERNEL          := hos
export CPPFLAGS := -I$(HOS_TOPLEVEL) -I$(HOS_TOPLEVEL)/include
export CFLAGS   := -Wall -O2
export CXXFLAGS := -Wall -O2 -fno-rtti -fno-exceptions
export LDFLAGS  := -T $(LDSCRIPT) -Map $(KERNEL).map
export LDLIBS   := `$(CC) -print-libgcc-file-name`

SUBDIRS         := boot mm lang isr
SUBDIRS_clean   := $(SUBDIRS:%=%.clean)

.PHONY: all
all: $(KERNEL).gz

$(KERNEL).gz: $(KERNEL)
	gzip -c $< > $@

$(KERNEL): $(KERNEL).o
	$(LD) $(LDFLAGS) -o $@ $<
	$(LD) $(LDFLAGS) --oformat=elf32-i386 -o $@.elf $<
	$(OBJDUMP) --disassemble --source $@.elf > $@.dump
	
$(KERNEL).o: $(SUBDIRS)
	$(LD) -r -o $@ $(foreach subdir,$(SUBDIRS),$(subdir)/$(subdir)_all.o) $(LDLIBS)

.PHONY: $(SUBDIRS)
$(SUBDIRS):
	$(MAKE) -C $@ SUBDIR=$@

.PHONY: clean
clean: $(SUBDIRS_clean)
	-rm -f *~ $(KERNEL) $(KERNEL).{gz,o,elf,dump,map}

%.clean:
	$(MAKE) -C $* clean clean=1