Makefile

BUILD_DIR := build
NASM := nasm
CC := i686-elf-gcc
LD := i686-elf-ld
OBJCOPY := i686-elf-objcopy
HOST_CC := gcc

CFLAGS := -ffreestanding -fno-stack-protector -fno-builtin -Wall -Wextra -Werror -std=gnu99 -m32 -I kernel
MODULE_CFLAGS := -ffreestanding -fno-stack-protector -fno-builtin -Wall -Wextra -Werror -std=gnu99 -m32 -I kernel -DMODULE_BUILD
LDFLAGS := -nostdlib -m elf_i386 -T kernel/link.ld

.DEFAULT_GOAL := all

STAGE1 := $(BUILD_DIR)/mbr.bin
STAGE2 := $(BUILD_DIR)/stage2.bin
KERNEL_ELF := $(BUILD_DIR)/kernel.elf
KERNEL_BIN := $(BUILD_DIR)/kernel.bin
DISK_IMG := $(BUILD_DIR)/proos.img
ISO_IMG := $(BUILD_DIR)/proos.iso
FAT16_IMG_TOOL := $(BUILD_DIR)/fat16_image.exe
FAT16_IMG := $(BUILD_DIR)/fat16.img
FAT16_SECTORS := 128
STAGE2_SECTORS := 4
# Reserve enough space for the kernel binary (current size ~132 KiB).
# Keep headroom so future growth does not truncate the image loading.
KERNEL_SECTORS := 384
KERNEL_OFFSET := 5
FAT16_OFFSET := $(shell expr $(KERNEL_OFFSET) + $(KERNEL_SECTORS))

IMG_SECTORS := 2880
EMBEDDED_FONT := assets/font.bdf
EMBEDDED_FONT_OBJ := $(BUILD_DIR)/embedded_font.o
EMBEDDED_FONT_SYMBOL_BASE := $(subst /,_,$(subst .,_,$(EMBEDDED_FONT)))
EMBEDDED_FONT_START := _binary_$(EMBEDDED_FONT_SYMBOL_BASE)_start
EMBEDDED_FONT_END := _binary_$(EMBEDDED_FONT_SYMBOL_BASE)_end

KERNEL_OBJS := $(BUILD_DIR)/crt0.o \
		   $(BUILD_DIR)/context.o \
		   $(BUILD_DIR)/isr.o \
		   $(BUILD_DIR)/irq.o \
		   $(BUILD_DIR)/syscall_entry.o \
		   $(BUILD_DIR)/idt.o \
		   $(BUILD_DIR)/pic.o \
		   $(BUILD_DIR)/pit.o \
		   $(BUILD_DIR)/ipc.o \
		   $(BUILD_DIR)/service.o \
		   $(BUILD_DIR)/process.o \
		   $(BUILD_DIR)/keyboard.o \
		   $(BUILD_DIR)/syscall.o \
		   $(BUILD_DIR)/kmain.o \
		   $(BUILD_DIR)/klog.o \
		   $(BUILD_DIR)/debug.o \
		   $(BUILD_DIR)/vga.o \
		   $(BUILD_DIR)/memory.o \
		   $(BUILD_DIR)/power.o \
		   $(BUILD_DIR)/vfs.o \
		   $(BUILD_DIR)/devicefs.o \
		   $(BUILD_DIR)/vbe.o \
		   $(BUILD_DIR)/gfx.o \
		   $(BUILD_DIR)/fatfs.o \
		   $(BUILD_DIR)/fat16.o \
		   $(BUILD_DIR)/shell.o \
		   $(BUILD_DIR)/ramfs.o \
		   $(BUILD_DIR)/devmgr.o \
		   $(BUILD_DIR)/spinlock.o \
		   $(BUILD_DIR)/sync.o \
		   $(BUILD_DIR)/pci.o \
		   $(BUILD_DIR)/e1000.o \
		   $(BUILD_DIR)/net.o \
		   $(BUILD_DIR)/net_socket.o \
		   $(BUILD_DIR)/ethernet.o \
		   $(BUILD_DIR)/arp.o \
		   $(BUILD_DIR)/ipv4.o \
		   $(BUILD_DIR)/icmp.o \
		   $(BUILD_DIR)/volmgr.o \
		   $(BUILD_DIR)/blockdev.o \
		   $(BUILD_DIR)/partition.o \
		   $(BUILD_DIR)/bios_fallback.o \
		   $(BUILD_DIR)/bios_thunk.o \
		   $(BUILD_DIR)/user/init.o \
		   $(BUILD_DIR)/user/echo_service.o \
		   $(BUILD_DIR)/user/logger.o \
		   $(BUILD_DIR)/user/fsd.o \
		   $(BUILD_DIR)/user/netd.o \
		   $(BUILD_DIR)/user/inputd.o \
		   $(BUILD_DIR)/string.o \
		   $(BUILD_DIR)/module.o \
		   $(BUILD_DIR)/module_symbols.o

MODULE_EXT := kmd
MODULES := fs ps2kbd ps2mouse pit rtc biosdisk ata time
MODULE_OBJS := $(addprefix $(BUILD_DIR)/modules/, $(addsuffix _module.o, $(MODULES)))
MODULE_MODS := $(addprefix $(BUILD_DIR)/modules/, $(addsuffix .$(MODULE_EXT), $(MODULES)))
MODULE_BLOBS := $(addprefix $(BUILD_DIR)/modules/, $(addsuffix _blob.o, $(MODULES)))

KERNEL_OBJS += $(MODULE_BLOBS)

DISK_MODULES := stub
DISK_MODULE_MODS := $(addprefix $(BUILD_DIR)/modules/, $(addsuffix .$(MODULE_EXT), $(DISK_MODULES)))

ifeq ($(wildcard $(EMBEDDED_FONT)),)
$(info [make] embedded font $(EMBEDDED_FONT) not found; framebuffer console will use BIOS/PSF-on-disk fonts only)
else
CFLAGS += -DHAVE_EMBEDDED_FONT -DEMBEDDED_FONT_START=$(EMBEDDED_FONT_START) -DEMBEDDED_FONT_END=$(EMBEDDED_FONT_END)
KERNEL_OBJS += $(EMBEDDED_FONT_OBJ)

$(EMBEDDED_FONT_OBJ): $(EMBEDDED_FONT) | $(BUILD_DIR)
	$(OBJCOPY) -I binary -O elf32-i386 -B i386 --rename-section .data=.rodata,alloc,load,readonly,data,contents $< $@
endif

.PHONY: all clean run-qemu iso
 
all: $(DISK_IMG)

$(BUILD_DIR):
	@mkdir -p $(BUILD_DIR)
	echo "[make] Created build directory: $@"

$(STAGE1): boot/mbr.asm | $(BUILD_DIR)
	$(NASM) -f bin $< -o $@
	echo "[make] Assembled stage1 bootloader: $@"

$(STAGE2): boot/stage2.asm | $(BUILD_DIR)
	$(NASM) -f bin -DSTAGE2_SECTORS=$(STAGE2_SECTORS) -DKERNEL_SECTORS=$(KERNEL_SECTORS) -DFAT16_SECTORS=$(FAT16_SECTORS) $< -o $@
	echo "[make] Assembled stage2 bootloader: $@"

$(BUILD_DIR)/crt0.o: kernel/crt0.s | $(BUILD_DIR)
	@mkdir -p $(dir $@)
	$(CC) $(CFLAGS) -c $< -o $@
	echo "[make] Compiled: $< -> $@" 

$(BUILD_DIR)/%.o: kernel/%.s | $(BUILD_DIR)
	@mkdir -p $(dir $@)
	$(CC) -m32 -c $< -o $@
	echo "[make] Assembled: $< -> $@"

$(BUILD_DIR)/%.o: kernel/%.S | $(BUILD_DIR)
	@mkdir -p $(dir $@)
	$(CC) -m32 -c $< -o $@
	echo "[make] Assembled: $< -> $@"

$(BUILD_DIR)/%.o: kernel/%.c | $(BUILD_DIR)
	@mkdir -p $(dir $@)
	$(CC) $(CFLAGS) -c $< -o $@
	echo "[make] Compiled: $< -> $@"

$(BUILD_DIR)/modules:
	@mkdir -p $(BUILD_DIR)/modules
	echo "[make] Created modules build directory: $@"

$(BUILD_DIR)/modules/%_module.o: modules/%_module.c | $(BUILD_DIR)/modules
	$(CC) $(MODULE_CFLAGS) -c $< -o $@
	echo "[make] Compiled module source: $< -> $@"

$(BUILD_DIR)/modules/%.$(MODULE_EXT): $(BUILD_DIR)/modules/%_module.o
	$(LD) -r -o $@ $<
	echo "[make] Linked module object: $< -> $@"

$(BUILD_DIR)/modules/%_blob.o: $(BUILD_DIR)/modules/%.$(MODULE_EXT)
	$(OBJCOPY) -I binary -O elf32-i386 -B i386 --rename-section .data=.rodata,alloc,load,readonly,data,contents $< $@
	echo "[make] Created module blob object: $< -> $@"

$(KERNEL_ELF): $(KERNEL_OBJS) kernel/link.ld | $(BUILD_DIR)
	$(LD) $(LDFLAGS) $(KERNEL_OBJS) -o $@
	echo "[make] Linked kernel ELF: $@"

$(KERNEL_BIN): $(KERNEL_ELF) | $(BUILD_DIR)
	$(OBJCOPY) -O binary $< $@
	echo "[make] Created kernel binary: $@"
$(FAT16_IMG_TOOL): kernel/fat16_image.c | $(BUILD_DIR)
	$(HOST_CC) -DFAT16_IMAGE_STANDALONE -o $@ $<
	echo "[make] Compiled FAT16 image tool: $@"

$(FAT16_IMG): $(FAT16_IMG_TOOL) $(DISK_MODULE_MODS) | $(BUILD_DIR)
	$< $@
	echo "[make] Created FAT16 image: $@"

$(DISK_IMG): $(STAGE1) $(STAGE2) $(KERNEL_BIN) $(FAT16_IMG) | $(BUILD_DIR)
	rm -f $@
	dd if=/dev/zero of=$@ bs=512 count=$(IMG_SECTORS) status=none
	dd if=$(STAGE1) of=$@ conv=notrunc status=none
	dd if=$(STAGE2) of=$@ bs=512 seek=1 conv=notrunc status=none
	dd if=$(KERNEL_BIN) of=$@ bs=512 seek=$(KERNEL_OFFSET) conv=notrunc status=none
	dd if=$(FAT16_IMG) of=$@ bs=512 seek=$(FAT16_OFFSET) conv=notrunc status=none
	echo "[make] Created disk image: $@"
	echo "[make] image built and compiled successfully."


$(ISO_IMG): $(DISK_IMG)
	bash iso/make_iso.sh $(DISK_IMG) $(ISO_IMG)
	echo "[make] Created ISO image: $@"

iso: $(ISO_IMG)

run-qemu: $(DISK_IMG)
	qemu-system-i386 -drive format=raw,file=$(DISK_IMG)
	echo "[make] Running QEMU with disk image: $(DISK_IMG)"

clean:
	rm -rf $(BUILD_DIR)
	echo "[make] Cleaned build artifacts."