# Copyright 2015 Philipp Oppermann
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

arch ?= x86_64
target ?= $(arch)-unknown-linux-gnu
kernel := build/kernel-$(arch).bin
iso := build/os-$(arch).iso

rust_os := target/$(target)/debug/libblog_os.a
linker_script := src/arch/$(arch)/linker.ld
grub_cfg := src/arch/$(arch)/grub.cfg
assembly_source_files := $(wildcard src/arch/$(arch)/*.asm)
assembly_object_files := $(patsubst src/arch/$(arch)/%.asm, \
	build/arch/$(arch)/%.o, $(assembly_source_files))

.PHONY: all clean run iso cargo

all: $(kernel)

clean:
	@cargo clean
	@rm -rf build

run: $(iso)
	@qemu-system-x86_64 -hda $(iso)

iso: $(iso)

$(iso): $(kernel)
	@mkdir -p build/isofiles/boot/grub
	@cp $(kernel) build/isofiles/boot/
	@cp $(grub_cfg) build/isofiles/boot/grub
	@grub-mkrescue -o $(iso) build/isofiles 2> /dev/null
	@rm -r build/isofiles

$(kernel): cargo $(rust_os) $(assembly_object_files) $(linker_script)
	@ld -n --gc-sections -T $(linker_script) -o $(kernel) $(assembly_object_files) $(rust_os)

cargo:
	@cargo rustc --target $(target) -- -Z no-landing-pads

# compile assembly files
build/arch/$(arch)/%.o: src/arch/$(arch)/%.asm
	@mkdir -p $(shell dirname $@)
	@nasm -felf64 $< -o $@