Makefile

TARGET := x86_64-unknown-none-elf
CC := clang
LD := ld.lld
HOST_CC ?= cc

BUILD := build
KERNEL := $(BUILD)/aster-kernel.elf
ISO := $(BUILD)/aster-kernel.iso
NET_TEST := $(BUILD)/tests/net_parser_test

CFLAGS := --target=$(TARGET) -std=c11 -O2 -g \
	-ffreestanding -fno-builtin -fno-stack-protector -fno-pic -fno-pie \
	-fno-strict-aliasing -fno-asynchronous-unwind-tables -fno-unwind-tables \
	-mno-red-zone -mcmodel=kernel -Wall -Wextra -Wpedantic -Werror \
	-Iinclude
ASFLAGS := --target=$(TARGET) -g -c
LDFLAGS := -nostdlib -static --fatal-warnings --no-undefined \
	-z max-page-size=0x1000 -T linker.ld
HOST_CFLAGS := -std=c11 -O2 -Wall -Wextra -Wpedantic -Werror -Iinclude

C_SOURCES := $(wildcard kernel/*.c arch/x86_64/*.c)
ASM_SOURCES := $(wildcard arch/x86_64/*.S)
OBJECTS := $(patsubst %.c,$(BUILD)/%.o,$(C_SOURCES)) \
           $(patsubst %.S,$(BUILD)/%.o,$(ASM_SOURCES))

QEMU ?= qemu-system-x86_64
QEMU_MEMORY ?= 256M

.PHONY: all kernel iso run run-gui run-headless run-direct clean check smoke tools

all: kernel

kernel: $(KERNEL)

$(KERNEL): $(OBJECTS) linker.ld
	@mkdir -p $(@D)
	$(LD) $(LDFLAGS) -o $@ $(OBJECTS)

$(BUILD)/%.o: %.c
	@mkdir -p $(@D)
	$(CC) $(CFLAGS) -c $< -o $@

$(BUILD)/%.o: %.S
	@mkdir -p $(@D)
	$(CC) $(ASFLAGS) $< -o $@

$(NET_TEST): tests/net_parser_test.c kernel/net.c
	@mkdir -p $(@D)
	$(HOST_CC) $(HOST_CFLAGS) $< -o $@

check: $(KERNEL) $(NET_TEST)
	@$(NET_TEST)
	@python3 scripts/check_kernel.py $(KERNEL)
	@python3 scripts/check_repo.py

iso: $(KERNEL)
	@command -v grub-mkrescue >/dev/null || { echo "Missing grub-mkrescue"; exit 1; }
	@command -v xorriso >/dev/null || { echo "Missing xorriso"; exit 1; }
	rm -rf $(BUILD)/isodir
	mkdir -p $(BUILD)/isodir/boot/grub
	cp $(KERNEL) $(BUILD)/isodir/boot/aster-kernel.elf
	cp grub/grub.cfg $(BUILD)/isodir/boot/grub/grub.cfg
	grub-mkrescue -o $(ISO) $(BUILD)/isodir

smoke: iso
	QEMU="$(QEMU)" QEMU_MEMORY="$(QEMU_MEMORY)" \
		python3 scripts/smoke_qemu.py "$(ISO)"

# Auto-detect GTK, SDL, or Cocoa. If none exists, keep the kernel usable
# by falling back to its colored serial console instead of aborting.
run: iso
	QEMU="$(QEMU)" QEMU_MEMORY="$(QEMU_MEMORY)" sh ./scripts/run_qemu.sh auto "$(ISO)"

# Require a real graphical window and print exact installation help if absent.
run-gui: iso
	QEMU="$(QEMU)" QEMU_MEMORY="$(QEMU_MEMORY)" sh ./scripts/run_qemu.sh gui "$(ISO)"

# Useful over SSH or when no graphical QEMU display module is installed.
run-headless: iso
	QEMU="$(QEMU)" QEMU_MEMORY="$(QEMU_MEMORY)" sh ./scripts/run_qemu.sh headless "$(ISO)"

run-direct: $(KERNEL)
	$(QEMU) -kernel $(KERNEL) -m $(QEMU_MEMORY) \
		-serial stdio -display none \
		-netdev user,id=net0,ipv6=off \
		-device rtl8139,netdev=net0,mac=52:54:00:12:34:56 \
		-no-reboot -no-shutdown

clean:
	rm -rf $(BUILD)

# Arch Linux / CachyOS host dependencies.
tools:
	@echo "sudo pacman -S --needed base-devel clang lld qemu-system-x86 qemu-ui-gtk grub xorriso mtools"