ARCHDIR=arch/i686

CFLAGS?=
ASFLAGS?=

INCLUDEDIR=include

CFLAGS:=\
-O2 \
-std=gnu99 \
-ffreestanding \
-Wall -Wextra \
-I$(INCLUDEDIR) \
$(CFLAGS)

ASFLAGS:=\
-I$(INCLUDEDIR) \
-I$(ARCHDIR) \
$(ASFLAGS)

KERNEL_OBJS=\
kernel/kernel.o \
kernel/debugging.o \
kernel/elf.o \

LIB_OBJS=\
$(ARCHDIR)/bootstrap.o \
$(ARCHDIR)/tty.o \
$(ARCHDIR)/strlib.o \
$(ARCHDIR)/idt.o \
$(ARCHDIR)/interrupt.o \
$(ARCHDIR)/gdt.o \

OBJS=$(KERNEL_OBJS) $(LIB_OBJS)

LDFLAGS=$(OBJS) \
-ffreestanding \
-O2 \
-nostdlib \
-lgcc

.PHONY: all clean myos.iso
.SUFFIXES: .c .o .s

all: myos.iso

clean:
	rm -f $(OBJS)
	rm -f myos.kernel
	rm -f myos.iso
	rm -f isodir/boot/myos.kernel

$(ARCHDIR)/interrupt.o: CFLAGS += -mgeneral-regs-only
kernel/elf.o: CFLAGS += -masm=intel

%.o : %.c
	i686-elf-gcc -c $< -o $@ $(CFLAGS)

%.o : %.s
	i686-elf-as $< -o $@ $(ASFLAGS)

myos.kernel: $(OBJS)
	i686-elf-gcc -T $(ARCHDIR)/linker.ld -o myos.kernel $(LDFLAGS)
	grub-file --is-x86-multiboot myos.kernel

myos.iso: myos.kernel
	cp myos.kernel isodir/boot/myos.kernel
	grub-mkrescue -o myos.iso isodir

debug: CFLAGS += -g -O0
debug: ASFLAGS += -g
debug: all

run: myos.iso
	qemu-system-i386 myos.iso

run-debug: debug
	qemu-system-i386 -S -gdb tcp::9000 myos.iso