#!/bin/sh

# generate a cpio entry for a command
gen_cmd() {
    cmdp="$(command -v "$1")" || exit 1
    printf 'file %s %s 0755 0 0\n' "$cmdp" "$cmdp"

    # ELF interpreter handled in cpio_list.txt
    ldd "$cmdp" | awk '$3~/^\// { print "file /lib64/" $1 " " $3 " 0755 0 0" }'
}

# generate the main file list
gen_cpio_list() {
    # static entries
    sed -e '/^#/d' cpio_list.txt

    # modules
    tr ' ' '\n' < modules.dep | sed -e "s/://;s:.*:file /lib/modules/$KERNVER/& /lib/modules/$KERNVER/& 0644 0 0:"

    # commands
    gen_cmd busybox
    gen_cmd cryptsetup
    gen_cmd dropbear
    gen_cmd e2fsck

    # cryptsetup needs libgcc_s.so.1 for pthread_cancel
    ldconfig -p | awk '$1 == "libgcc_s.so.1" && $2 ~ /x86-64/ { print "file /lib64/" $1 " " $4 " 0755 0 0" }'
}

# insert parent directory entries
gen_dir_ents() {
    awk '{ print; while (sub("/[^/]*$", "", $2) && $2) print "dir " $2 " 0755 0 0" }'
}

# generate the make dependency file
gen_depfile() {
    awk -v f=/dev/fd/3 -v deps="cpio_list.txt make" '
        { print }
        $1 == "file" && $3 != "/dev/null" { deps=deps " " $3 }
        END { print "DEPS = " deps "\n$(DEPS):\ninitramfs.img: $(DEPS)" > f }
    '
}

gen_cpio_list | gen_dir_ents | sort -uk2 | gen_depfile 3>initramfs.d | ./gen_init_cpio -t 0 - | $COMPRESSOR > initramfs.img