Setup

#!/usr/bin/setup -f
declare BUILD=.build SRC=src
declare -g OMEGA_PREFIX="$SETUP_PREFIX"

declare -a sources=( $(find "$SRC" -name '*.c' -o -name '*.s') )
declare -a objects=( "${sources[@]/#$SRC\//$BUILD/}" )
objects=( "${objects[@]/%/.o}" )

declare arg
declare -a o_files=( )

prepare "$BUILD/constants.S" = Omega.ASMConstants "$SRC/constants.h"
prepare "$BUILD/ld.conf" = Omega.LD.conf "$SRC/constants.h"
for arg in boot/kmain.S "${sources[@]#$SRC/}"; do
    case "$arg" in
	*.s|*.S) prepare "$BUILD/$arg.o" = Omega.ASM "$SRC/$arg" "$BUILD/constants.S" -felf32;;
	*.c)     prepare "$BUILD/$arg.o" = Omega.CC "$SRC/$arg";;
    esac
    o_files+=( "$BUILD/$arg.o" )
done
prepare "$BUILD/kernel.bin" = Omega.LD "$BUILD/ld.conf" "${o_files[@]}"
prepare "$BUILD/bootsector.bin" = Omega.ASM "$SRC/boot/bootsector.S" "$BUILD/constants.S"
prepare "$BUILD/Omega.img" = Omega.IMG "$BUILD/"{bootsector,kernel}".bin"

if Setup.params -package; then
    Setup.use Pkg
    Pkg.package Pkg.files usr/share/omega/Omega.img=.build/Omega.img
fi

function Omega.IMG() {
    local out="$1" ; shift
    local bootsect="$1" kernel="$2"

    mkpdir "$out"

    cat "$bootsect" "$kernel" /dev/zero 2> /dev/null \
	| dd if='/dev/stdin' of="$out" bs=512 count=128 conv=notrunc 2> /dev/null
}
function Omega.ASMConstants() { mkpdir "$1"; sed -rn 's/^#define/%define/p' "$2" > "$1"; }
function Omega.ASM() {
    mkpdir "$1"
    nasm -i "${OMEGA_PREFIX}.build/" -i "${OMEGA_PREFIX}src/" $4 "$2" -o "$1"
}
function Omega.CC() {
    mkpdir "$1"
    gcc -Werror -Wall -Wno-char-subscripts -fno-builtin -nostdlib -Os -m32 -c -I"${OMEGA_PREFIX}src" "$2" -o "$1"
}

function Omega.LD() {
    local out="$1" ; shift
    local script="$1"; shift

    mkpdir "$out"

    ld -T "$script" -m elf_i386 -o "$out"  "$@"
}
function Omega.LD.conf() {
    local src="$2"
    local entry="$(sed -rn 's/#define\s+KERNEL_START\s+//p' "$src")"

    mkpdir "$1"
    cat > "$1" <<EOF
OUTPUT_FORMAT("binary")
SECTIONS
{
  . = $entry;
  .text : {
    KERNEL_CODE = .;
    *(.text)
    *(.rodata)
  }
  .data ALIGN(8) : {
    KERNEL_DATA = .;
    *(.data)
  }
  .bss ALIGN(8) : {
    KERNEL_BSS = .;
    *(.bss)
  }
  KERNEL_END = .;
}
EOF
}

# Local Variables:
# mode: shell-script
# sh-shell: bash
# End: