#!/bin/sh -e

# POSIX install functions, similar to 'install -Dm'
# and 'install -Dm* -t'
kinstall() {
    # usage: kinstall 644 file /usr/bin/prog
    mkdir -p "${3%/*}"; rmdir "$3" 2>/dev/null ||:
    cp "$2" "$3"
    [ -d "$3" ] && set -- "$1" "$3/${2##*/}"
    chmod "$1" "${3:-$2}"
}

kinstall_t() {
    # usage: kinstall_t 644 /usr/bin prog1 prog2
    mod=$1 dir=$2; mkdir -p "$dir"
    shift 2
    for file; do
        cp "$file" "$dir"
        chmod "$mod" "$dir/${file##*/}"
    done
}

# Use an out function similar to KISS' log.
out() { printf '\033[1;33m-> \033[1;36mlinux \033[m%s\n' "$@" >&2 ;}

ROOT=$PWD
ver=$(make -C linux -s kernelversion)

# Prepare the kernel sources first.
(
    out "Preparing the kernel"
    cd linux
    patch -p1 < kernel-no-perl.patch

    cp .config oldconfig
    ./scripts/config -e modules
    make olddefconfig
    make prepare
)

(
    out "Preparing zfs modules"
    cd zfs

    sed -i 's|CDDL|GPL|g' META

    ./configure \
        --prefix=/usr \
        --sysconfdir=/etc \
        --sbindir=/usr/bin \
        --disable-systemd \
        --disable-sysvinit \
        --disable-nls \
        --enable-linux-builtin \
        --with-linux="$ROOT/linux"

    sed -i "/^KERNEL_DIR/s|^.*|KERNEL_DIR=$ROOT/linux|" copy-builtin
    ./copy-builtin "$ROOT/linux"
)

(
    cd linux

    # Enable zfs
    ./scripts/config -e zfs -d modules

    out "Compiling the kernel"
    make

    out "Installing the kernel"
    install -Dm644 "$(make -s image_name)" "$1/boot/vmlinuz-$ver"
    install -Dm644 System.map              "$1/boot/System.map-$ver"
    install -Dm644 oldconfig               "$1/boot/Config-$ver"
)