improve portability, code quality, fix bugs, etc...

Makefile

@@ -4,10 +4,17 @@ BINDIR     = ${PREFIX}/bin
 DATADIR    = ${PREFIX}/share
 
 install:
-	install -Dm600 config        ${DESTDIR}${SYSCONFDIR}/tinyramfs/config
+	mkdir -p \
-	install -Dm755 tinyramfs     ${DESTDIR}${BINDIR}/tinyramfs
+		${DESTDIR}${DATADIR}/tinyramfs/hooks \
-	install -Dm755 init          ${DESTDIR}${DATADIR}/tinyramfs/init
+		${DESTDIR}${SYSCONFDIR}/tinyramfs \
-	install -Dm755 device-helper ${DESTDIR}${DATADIR}/tinyramfs/device-helper
+		${DESTDIR}${BINDIR}
+	cp -R hooks/*         ${DESTDIR}${DATADIR}/tinyramfs/hooks/
+	cp init device-helper ${DESTDIR}${DATADIR}/tinyramfs
+	chmod -R 644     	  ${DESTDIR}${DATADIR}/tinyramfs
+	cp config 		 	  ${DESTDIR}${SYSCONFDIR}/tinyramfs
+	chmod 600 		 	  ${DESTDIR}${SYSCONFDIR}/tinyramfs/config
+	cp tinyramfs 	 	  ${DESTDIR}${BINDIR}/tinyramfs
+	chmod 755    	 	  ${DESTDIR}${BINDIR}/tinyramfs
 
 uninstall:
 	rm -f  ${DESTDIR}${BINDIR}/tinyramfs

README.md

@@ -7,27 +7,24 @@ Features
 --------
 
 - No `local`'s, no bashisms, only POSIX shell
-- Easy configuration
+- Portable, not distro specific
+- Easy to use configuration
+- Build time and init time hooks
+- LUKS (detached header, key), LVM
 - mdev, mdevd, eudev
-- LUKS, LVM
-- LUKS detached header and key embedded into initramfs
 
 Dependencies
 ------------
 
-* POSIX utilities ( find, mkdir, ... )
+* POSIX utilities
 * POSIX shell
 * `switch_root`
-* `readlink`
-* `install`
 * `mount`
 * `blkid`
 * `cpio`
-* `strip`
+* POSIX SD `strip`
   - Optional
-* `gzip`
+* `mdev` OR `mdevd` OR `eudev` OR `systemd-udevd`
-  - Required by default
-* `mdev` OR `mdevd` OR `eudev`
   - systemd-udevd not tested
 * `lvm2`
   - Required for LVM support
@@ -39,9 +36,8 @@ Dependencies
 Notes
 -----
 
-* busybox modutils doesn't handle soft dependencies (modules.softdep). You must manually include them using `modules` config option
+* busybox modutils doesn't handle soft dependencies (modules.softdep). You must manually copy them using hooks
-* busybox and toybox blkid doesn't support PARTUUID. You must use util-linux blkid
+* busybox and toybox blkid doesn't support PARTUUID. You must use util-linux blkid for PARTUUID support
-* zsh (in POSIX mode) shows some errors in init stage. Just ignore these errors, it's harmless
 * `cp` in toybox incorrectly handles `-P` flag. You need to apply patch from [this issue](https://github.com/landley/toybox/issues/174) or replace cp with another implementation
 
 Installation
@@ -57,20 +53,6 @@ tinyramfs -o /boot/initramfs
 # reboot...
 ```
 
-Usage
------
-
-```
-usage: tinyramfs [option]
-       -o, --output <file> set initramfs output path
-       -c, --config <file> set config file path
-       -m, --moddir <dir>  set modules directory
-       -k, --kernel <ver>  set kernel version
-       -F, --files  <dir>  set files directory
-       -d, --debug         enable debug mode
-       -f, --force         overwrite initramfs image
-```
-
 Configuration
 -------------
 

config

@@ -2,23 +2,9 @@
 # configuration
 #
 # uncomment and fill settings which you needed
-
-# debug mode
-# default - 0
 #
-#debug=0|1
+# 0 - disable
-
+# 1 - enable
-# overwrite initramfs
-# default - 0
-#
-#force=0|1
-
-# initramfs output path
-#
-# default - /tmp/initramfs-$kernel
-# example - output="/tmp/myinitramfs.img.gz"
-#
-#output=""
 
 # monolithic kernel
 #
@@ -27,48 +13,35 @@
 #
 #monolith=0|1
 
-# modules directory
-#
-# default - /lib/modules
-# example - moddir="/mnt/root/lib/modules"
-#
-#moddir=""
-
-# kernel version
-#
-# default - $(uname -r)
-# example - kernel="5.4.18_1"
-#
-#kernel=""
-
 # compression program
 #
-# default - gzip -9
+# supported - whatever you choose
-# example -
+# default - none
-#   compress="pigz -9"
+# example - compress="pigz -9"
-#   compress="none" # disable compress
 #
 #compress=""
 
-# root
+# root file system
 #
-# supported - PARTUUID, DEVICE, LABEL, UUID
+# supported - UUID, LABEL, DEVICE, PARTUUID
 # example -
 #   root="/dev/sda1"
 #   root="/dev/dm-0"
+#   root="/dev/disk/by-uuid/13bcb7cc-8fe5-4f8e-a1fe-e4b5b336f3ef"
 #   root="PARTUUID=35f923c5-083a-4950-a4da-e611d0778121"
 #
 #root=""
 
-# root type
+# root file system type
 #
-# default - autodetected
+# default - autodetected throught /proc/mounts
 # example - root_type="btrfs"
 #
 #root_type=""
 
-# root options
+# root file system options
-# example - see fstab(5)
+# example - root_opts="subvol=mysubvolume,nodatacow,defaults"
+# see fstab(5) man page for more info
 #
 #root_opts=""
 
@@ -79,72 +52,57 @@
 
 # hostonly mode
 #
+# default - 0
 # dramatically reduce initramfs size
 # useful only for modular kernels
 #
 #hostonly=0|1
 
-# additional modules
+# hooks
-# example - modules="fat crc32c_generic"
 #
-#modules=""
+# currently supported - lvm, luks
-
+# example -
-# exclude modules
+#   hooks="lvm luks" will support booting LUKS on LVM
-# example - modules_exclude="wmi fuse"
+#   hooks="luks lvm" will support booting LVM on LUKS
+#   hooks="luks"     will support booting only LUKS
+#   and so on...
 #
-#modules_exclude=""
+#hooks=""
-
-# additional binaries
-# example - binaries="ls cat /path/to/mycustomprog"
-#
-#binaries=""
-
-# LVM support
-# default - 0
-#
-#lvm=0|1
 
 # LVM options
 #
 # supported - tag, name, group, config, discard
 # description -
 #   tag - trigger lvm by tag
-#   name - trigger lvm by logical volume name
+#   name - trigger lvm by logical volume name. group must be specified
 #   group - trigger lvm by volume group name
 #   config - embed host lvm config
 #   discard - enable issue_discards
 # example -
 #   lvm_opts="tag=lvm-server"
 #   lvm_opts="name=lv1,group=vg1"
-#   lvm_opts="config=1,discard"
+#   lvm_opts="config=1,discard=1"
 #   lvm_opts="discard=1"
 #
 #lvm_opts=""
 
-# LUKS support
-# default - 0
-#
-#luks=0|1
-
-# LUKS encrypted root
-#
-# supported - PARTUUID, DEVICE, LABEL, UUID
-# example -
-#   luks_root="/dev/sda1"
-#   luks_root="PARTUUID=35f923c5-083a-4950-a4da-e611d0778121"
-#
-#luks_root=""
-
 # LUKS options
 #
-# supported - key, name, header, discard
+# supported - key, name, root, header, discard
 # description -
 #   key - embed key
 #   name - device mapper name
+#   root - encrypted root ( UUID, LABEL, DEVICE, PARTUUID )
 #   header - embed header
 #   discard - enable allow-discards
 # example -
-#   luks_opts="key=/path/to/keyfile,name=myluksroot,header=/path/to/header,discard"
+#   luks_opts="root=PARTUUID=35f923c5-083a-4950-a4da-e611d0778121,key=/path/to/keyfile,name=myluksroot,header=/path/to/header,discard=1"
-#   luks_opts="discard=1"
+#   luks_opts="root=PARTUUID=35f923c5-083a-4950-a4da-e611d0778121,
+#              key=/path/to/keyfile,
+#              name=myluksroot,
+#              header=/path/to/header,
+#              discard=1"
+#
+#   luks_opts="root=/dev/sda1,discard=1"
 #
 #luks_opts=""

device-helper

@@ -6,7 +6,6 @@ create_symlink()
 {
     dir="$1"; sym="$2"
 
-    # remove double quotes
     sym="${sym%\"}"
     sym="${sym#\"}"
     sym="${dir}/${sym}"
@@ -20,7 +19,7 @@ create_symlink()
     [ -b "/dev/${dev_name=${DEVPATH##*/}}" ] || exit 1
 
     # prevent race condition
-    while ! blkid "/dev/${dev_name}"; do sleep 1; done
+    blkid "/dev/${dev_name}" || sleep 2
 
     for line in $(blkid "/dev/${dev_name}"); do case   "${line%%=*}" in
         UUID)     create_symlink /dev/disk/by-uuid     "${line##*=}" ;;

hooks/luks/luks

@@ -0,0 +1,37 @@
+# vim: set ft=sh:
+#
+# handle_luks()
+{
+    print "configuring LUKS"
+
+    [ "$hostonly" = 1 ] &&
+        for _module in \
+            aes ecb xts lrw wp512 sha256 \
+            sha512 twofish serpent dm-crypt
+        do
+            copy_module "$_module"
+        done
+
+    copy_binary cryptsetup
+
+    # avoid possible issues with libgcc_s.so.1
+    # see https://bugs.archlinux.org/task/56771
+    [ -e /lib/libgcc_s.so.1 ] && copy_library /lib/libgcc_s.so.1
+
+    # word splitting is safe by design
+    # shellcheck disable=2086
+    IFS=,; set -- $luks_opts; unset IFS
+
+    set -C; for opt; do case "${opt%%=*}" in
+        key | header)
+            cp "${opt#*=}" "${tmpdir}/root/${opt%%=*}"
+            chmod 400      "${tmpdir}/root/${opt%%=*}"
+
+            sed "s|${opt#*=}|/root/${opt%%=*}|" \
+                "${tmpdir}/etc/tinyramfs/config" > "${tmpdir}/_"
+
+            cp "${tmpdir}/_" "${tmpdir}/etc/tinyramfs/config"
+            chmod 600        "${tmpdir}/etc/tinyramfs/config"
+            rm "${tmpdir}/_"
+    esac || panic; done; set +C
+}

hooks/luks/luks.init

@@ -0,0 +1,31 @@
+# vim: set ft=sh:
+#
+# unlock_luks()
+{
+    [ "$break" = luks ] && { print "break before unlock_luks()"; sh; }
+
+    mkdir -p /run/cryptsetup
+
+    IFS=,; set -- $luks_opts; unset IFS
+
+    for opt; do case "$opt" in
+        discard=1) luks_discard="--allow-discards" ;;
+        header=*)  luks_header="--${opt}"  ;;
+        name=*)    luks_name="${opt#*=}"   ;;
+        root=*)    luks_root="${opt#*=}"   ;;
+        key=*)     luks_key="-d ${opt#*=}" ;;
+    esac; done
+
+    resolve_device "$luks_root"
+
+    set -- \
+        "$luks_key" "$luks_header" "$luks_discard" \
+        "$device" "${luks_name:-crypt-${device##*/}}"
+
+    # libdevice-mapper assumes that udev has dm rules
+    # which is not true because we use our device-helper for dm stuff
+    # this variable fixes possible(?) hang
+    export DM_DISABLE_UDEV=1
+
+    cryptsetup open $@ || panic "failed to unlock LUKS"
+}

hooks/lvm/lvm

@@ -0,0 +1,44 @@
+# vim: set ft=sh:
+#
+# handle_lvm()
+{
+    print "configuring LVM"
+
+    [ "$hostonly" = 1 ] &&
+        for _module in \
+            dm-log dm-cache dm-mirror \
+            dm-snapshot dm-multipath dm-thin-pool
+        do
+            copy_module "$_module"
+        done
+
+    copy_binary lvm
+
+    lvm_config="
+        devices {
+            write_cache_state = 0
+        }
+        backup {
+            backup  = 0
+            archive = 0
+        }
+        global {
+            use_lvmetad = 0
+        }"
+
+    # word splitting is safe by design
+    # shellcheck disable=2086
+    IFS=,; set -- $lvm_opts; unset IFS
+
+    for opt; do case "$opt" in
+        config=1) embed_lvm_config=
+    esac; done
+
+    mkdir -p "${tmpdir}/etc/lvm"
+
+    lvm config \
+        --config "$lvm_config" \
+        ${embed_lvm_config+--mergedconfig} \
+    > "${tmpdir}/etc/lvm/lvm.conf"
+}
+

hooks/lvm/lvm.init

@@ -0,0 +1,35 @@
+# vim: set ft=sh:
+#
+# trigger_lvm()
+{
+    [ "$break" = lvm ] && { print "break before trigger_lvm()"; sh; }
+
+    mkdir -p /run/lvm /run/lock/lvm
+
+    IFS=,; set -- $lvm_opts; unset IFS
+
+    for opt; do case "$opt" in
+        discard=1) lvm_discard="--config=devices{issue_discards=1}" ;;
+        config=0)  : > /etc/lvm/lvm.conf  ;;
+        group=*)   lvm_group="${opt##*=}" ;;
+        name=*)    lvm_name="/${opt##*=}" ;;
+        tag=*)     lvm_tag="@${opt##*=}"  ;;
+    esac; done
+
+    set -- "--sysinit" "-qq" "-aay" "$lvm_discard"
+
+    # libdevice-mapper assumes that udev have dm rules
+    # which is not true because we use our device-helper for dm stuff
+    # this variable fixes possible(?) hang
+    export DM_DISABLE_UDEV=1
+
+    if [ "$lvm_group" ] && [ "$lvm_name" ]; then
+        lvm lvchange $@ "${lvm_group}${lvm_name}"
+    elif [ "$lvm_group" ]; then
+        lvm vgchange $@ "$lvm_group"
+    elif [ "$lvm_tag" ]; then
+        lvm lvchange $@ "$lvm_tag"
+    else
+        lvm vgchange $@
+    fi || panic "failed to trigger LVM"
+}

init

@@ -1,12 +1,7 @@
-#!/bin/sh -ef
+#!/bin/sh
 #
 # tiny init
 #
-# word splitting is safe by design
-# shellcheck disable=2068,2046,2086
-#
-# false positive
-# shellcheck disable=2154,2163,1091
 
 print()
 {
@@ -21,21 +16,33 @@ panic()
 
 resolve_device()
 {
-    count=0; device=
+    count=0; device="$1"
 
-    case "${1%%=*}" in
+    case "${device%%=*}" in /dev/*) ;;
-        /dev/*)   device="$1"                             ;;
+        UUID)     device="/dev/disk/by-uuid/${device#*=}"     ;;
-        UUID)     device="/dev/disk/by-uuid/${1##*=}"     ;;
+        LABEL)    device="/dev/disk/by-label/${device#*=}"    ;;
-        LABEL)    device="/dev/disk/by-label/${1##*=}"    ;;
+        PARTUUID) device="/dev/disk/by-partuuid/${device#*=}" ;;
-        PARTUUID) device="/dev/disk/by-partuuid/${1##*=}" ;;
     esac
 
     # prevent race condition
+    # XXX what the hell happens here?
+    # why this loop sometimes trigger panic if i remove '|| :'
     while [ ! -b "$device" ]; do sleep 1
-        [ "$(( count += 1 ))" != 30 ] || {
+        [ "$((count += 1))" = 30 ] && {
             panic "failed to lookup partition"
             break
         }
+    done || :
+}
+
+run_hook()
+{
+    type="$1"; hksdir=/usr/share/tinyramfs/hooks
+
+    # run hooks if any
+    for hook in $hooks; do
+        [ -f "${hksdir}/${hook}/${hook}.${type}" ] || continue
+           . "${hksdir}/${hook}/${hook}.${type}"
     done
 }
 
@@ -45,23 +52,17 @@ prepare_environment()
 
     export \
         PATH=/bin TERM=linux SHELL=/bin/sh \
-        LANG=C LC_ALL=C PS1="# " HOME=/root \
+        LANG=C LC_ALL=C PS1="# " HOME=/root
 
     mount -t proc     -o nosuid,noexec,nodev     proc /proc
     mount -t sysfs    -o nosuid,noexec,nodev     sys  /sys
     mount -t tmpfs    -o nosuid,nodev,mode=0755  run  /run
     mount -t devtmpfs -o nosuid,noexec,mode=0755 dev  /dev
 
-    mkdir -p /run/cryptsetup /run/lock /run/lvm
-
     ln -s /proc/self/fd /dev/fd
     ln -s fd/0          /dev/stdin
     ln -s fd/1          /dev/stdout
     ln -s fd/2          /dev/stderr
-
-    trap panic EXIT
-
-    [ ! "$modules" ] || modprobe -a "$modules"
 }
 
 parse_cmdline()
@@ -69,14 +70,14 @@ parse_cmdline()
     read -r cmdline < /proc/cmdline
 
     for line in $cmdline; do case  "$line"  in
-        debug | debug=1) set -x             ;;
+        rootfstype=*)    root_type="${line#*=}" ;;
-        rootfstype=*)    root_type="${line##*=}" ;;
+        rootflags=*)     root_opts="${line#*=}" ;;
-        rootflags=*)     root_opts="${line##*=}" ;;
+        debug=1)         set -x             ;;
         ro | rw)         rorw="-o $line"    ;;
-        --*)             init_args="${cmdline##*--}"; break ;;
+        --*)             init_args="${cmdline#*-- }"; break ;;
         *=*)             command export "$line"     ;;
         *)               command export "${line}=1" ;;
-    esac 2> /dev/null || continue; done
+    esac 2> /dev/null || :; done
 }
 
 setup_devmgr()
@@ -107,55 +108,6 @@ setup_devmgr()
     esac 2> /dev/null
 }
 
-unlock_luks()
-{
-    [ "$break" = luks ] && { print "break before unlock_luks()"; sh; }
-
-    { IFS=,; set -- $luks_opts; unset IFS; }
-
-    for opt; do case "$opt" in
-        discard | discard=1) luks_discard="--allow-discards" ;;
-        header=*) luks_header="--${opt}"   ;;
-        name=*)   luks_name="${opt##*=}"   ;;
-        key=*)    luks_key="-d ${opt##*=}" ;;
-    esac; done
-
-    resolve_device "$luks_root"
-
-    set -- \
-        "$luks_key" "$luks_header" "$luks_discard" \
-        "$device" "${luks_name:-crypt-${device##*/}}"
-
-    cryptsetup open $@ || panic "failed to unlock LUKS"
-}
-
-trigger_lvm()
-{
-    [ "$break" = lvm ] && { print "break before trigger_lvm()"; sh; }
-
-    { IFS=,; set -- $lvm_opts; unset IFS; }
-
-    for opt; do case "$opt" in
-        discard | discard=1) lvm_discard="--config=devices{issue_discards=1}" ;;
-        config=0) : > /etc/lvm/lvm.conf  ;;
-        group=*)  lvm_group="${opt##*=}" ;;
-        name=*)   lvm_name="/${opt##*=}" ;;
-        tag=*)    lvm_tag="@${opt##*=}"  ;;
-    esac; done
-
-    set -- "--sysinit" "-qq" "-aay" "$lvm_discard"
-
-    if [ "$lvm_group" ] && [ "$lvm_name" ]; then
-        lvm lvchange $@ "${lvm_group}${lvm_name}"
-    elif [ "$lvm_group" ]; then
-        lvm vgchange $@ "$lvm_group"
-    elif [ "$lvm_tag" ]; then
-        lvm lvchange $@ "$lvm_tag"
-    else
-        lvm vgchange $@
-    fi || panic "failed to trigger LVM"
-}
-
 mount_root()
 {
     [ "$break" = root ] && { print "break before mount_root()"; sh; }
@@ -184,6 +136,7 @@ boot_system()
 
     set -- "/mnt/root" "${init:-/sbin/init}" "$init_args"
 
+    # POSIX exec has no -c flag to execute command with empty environment
     # use 'env -i' to prevent leaking exported variables
     exec env -i \
         TERM=linux \
@@ -193,14 +146,16 @@ boot_system()
 
 # int main()
 {
+    # enable exit on error and disable globbing
+    # trap EXIT signal
+    set -ef; trap panic EXIT
+
     prepare_environment
+    run_hook init.early
     parse_cmdline
     setup_devmgr
 
-    # trigger lvm twice to handle both LUKS on LVM and LVM on LUKS
+    run_hook init
-    [ "$lvm"  = 1 ] && trigger_lvm
-    [ "$luks" = 1 ] && unlock_luks
-    [ "$lvm"  = 1 ] && trigger_lvm
 
     mount_root
     boot_system

tinyramfs

@@ -2,8 +2,6 @@
 #
 # tiny initramfs
 #
-# false positive
-# shellcheck disable=2154
 
 print()
 {
@@ -19,41 +17,58 @@ panic()
 usage()
 {
     cat << EOF
-usage: $0 [option]
+usage: ${0##*/} [option...]
        -o, --output <file> set initramfs output path
+                           default is /boot/initramfs-$(uname -r)
+
        -c, --config <file> set config file path
-       -m, --moddir <dir>  set modules directory
+                           default is /etc/tinyramfs/config
+
+       -m, --modules <dir> set modules directory
+                           default is /lib/modules
+
+       -s, --sources <dir> set sources directory
+                           default is /usr/share/tinyramfs
+
        -k, --kernel  <ver> set kernel version
-       -F, --files  <dir>  set files directory
+                           default is $(uname -r)
+
+       -H, --hooks   <dir> set hooks directory
+                           default is /etc/tinyramfs/hooks (user hooks)
+                           and /usr/share/tinyramfs/hooks (system hooks)
+
        -d, --debug         enable debug mode
        -f, --force         overwrite initramfs image
 
 EOF
 }
 
-parse_args()
+prepare_environment()
 {
     while [ "$1" ]; do case "$1" in
         -o | --output)
-            _output="${2:?}"; shift 2
+            output="${2:?}"; shift 2
         ;;
         -c | --config)
-            _config="${2:?}"; shift 2
+            config="${2:?}"; shift 2
         ;;
-        -m | --moddir)
+        -m | --modules)
-            _moddir="${2:?}"; shift 2
+            moddir="${2:?}"; shift 2
+        ;;
+        -s | --sources)
+            srcdir="${2:?}"; shift 2
         ;;
         -k | --kernel)
-            _kernel="${2:?}"; shift 2
+            kernel="${2:?}"; shift 2
         ;;
-        -F | --files)
+        -H | --hooks)
-            _filesdir="${2:?}"; shift 2
+            hksdir="${2:?}"; shift 2
         ;;
         -d | --debug)
-            _debug=1; shift 1
+            debug=1; shift 1
         ;;
         -f | --force)
-            _force=1; shift 1
+            force=1; shift 1
         ;;
         -h | --help)
             usage; exit 0
@@ -64,370 +79,81 @@ parse_args()
             usage; exit 1
         ;;
     esac; done
-}
 
-prepare_environment()
-{
     print "preparing environment"
 
-    # false positive
+    . "${config:-/etc/tinyramfs/config}"
-    # shellcheck disable=1090
-    for _file in "$_config" /etc/tinyramfs/config; do
-        [ -f "$_file" ] && { . "$_file"; break; }
-    done || panic "failed to source config"
 
-    for _dir in "$_filesdir" /usr/share/tinyramfs; do
+    : "${kernel:=$(uname -r)}"
-        [ -d "$_dir" ] && { filesdir="$_dir"; break; }
+    : "${moddir:=/lib/modules}"
-    done || panic "failed to locate required files"
+    : "${srcdir:=/usr/share/tinyramfs}"
+    : "${output:=/boot/tinyramfs-${kernel}}"
 
-    # general variables
+    mkdir -p "${tmpdir:=${TMPDIR:-/tmp}/tinyramfs.$$}"
-    debug="${_debug:-${debug:-0}}"
-    force="${_force:-${force:-0}}"
-    moddir="${_moddir:-${moddir:-/lib/modules}}"
-    kernel="${_kernel:-${kernel:-$(uname -r)}}"
-    output="${_output:-${output:-/tmp/initramfs-${kernel}}}"
-
-    mkdir -p "${workdir=${XDG_CACHE_HOME:-${TMPDIR:-/tmp}}/initramfs.$$}"
-
-    # helpers variables
-    workdirbin="${workdir}/usr/bin/"
-    workdirlib="${workdir}/usr/lib/"
-    modker="${moddir}/${kernel}"
 
     # false positive
     # shellcheck disable=2015
-    [ "$debug" = 1 ] && set -x || trap trap_helper EXIT INT
+    [ "$debug" = 1 ] && set -x || trap "rm -rf $tmpdir" EXIT INT
 }
 
-trap_helper()
+prepare_initramfs()
 {
-    [ "${ret=$?}" = 0 ] ||
+    print "preparing initramfs"
-        print "unexpected error occurred" \
-        "\033[1;31m!!\033[m" >&2
-
-    print "removing working directory"; rm -rf "$workdir"
-    exit "$ret"
-}
-
-populate_config()
-{
-    printf "%s\n" "$@" >> "${workdir}/etc/tinyramfs/config"
-}
-
-install_requirements()
-{
-    print "installing requirements"
-
-    # install required binaries
-    for _binary in \[ sh ln kill mkdir env \
-                   blkid sleep mount printf \
-                   switch_root "${filesdir}/device-helper"
-    do
-        install_binary "$_binary"
-    done
-
-    # install user specified binaries
-    for _binary in $binaries; do
-        install_binary "$_binary"
-    done
-
-    # install init
-    install -m755 "${filesdir}/init" "${workdir}/init"
-
-    # fix ubase mount issue
-    : > "${workdir}/etc/fstab"
-
-    populate_config \
-        "root='$root'" \
-        "devmgr='$devmgr'" \
-        "root_type='$root_type'" \
-        "root_opts='$root_opts'"
-}
-
-create_structure()
-{
-    print "creating directory structure"
 
+    # make directories
     mkdir -p \
-        "${workdir}/dev" \
+        "${tmpdir}/dev" \
-        "${workdir}/sys" \
+        "${tmpdir}/sys" \
-        "${workdir}/tmp" \
+        "${tmpdir}/tmp" \
-        "${workdir}/run" \
+        "${tmpdir}/run" \
-        "${workdir}/var" \
+        "${tmpdir}/var" \
-        "${workdir}/proc" \
+        "${tmpdir}/proc" \
-        "${workdir}/root" \
+        "${tmpdir}/root" \
-        "${workdir}/usr/lib" \
+        "${tmpdir}/usr/lib" \
-        "${workdir}/usr/bin" \
+        "${tmpdir}/usr/bin" \
-        "${workdir}/mnt/root" \
+        "${tmpdir}/mnt/root" \
-        "${workdir}/etc/tinyramfs"
+        "${tmpdir}/etc/tinyramfs"
-}
 
-create_symlinks()
+    # make symlinks
-{
+    ln -s usr/lib "${tmpdir}/lib"
-    print "creating symlinks"
+    ln -s usr/bin "${tmpdir}/bin"
+    ln -s usr/bin "${tmpdir}/sbin"
+    ln -s ../run  "${tmpdir}/var/run"
+    ln -s ../run/lock "${tmpdir}/var/lock"
+    ln -s bin     "${tmpdir}/usr/sbin"
 
-    ln -s usr/lib "${workdir}/lib"
+    # TODO make blkid optional
-    ln -s usr/lib "${workdir}/lib64"
+    # copy required binaries
-    ln -s usr/bin "${workdir}/bin"
+    for _binary in \
-    ln -s usr/bin "${workdir}/sbin"
+        \[ sh ln env kill mkdir \
-    ln -s ../run  "${workdir}/var/run"
+        blkid sleep mount printf \
-    ln -s ../run/lock "${workdir}/var/lock"
+        switch_root "${srcdir}/device-helper"
-    ln -s bin     "${workdir}/usr/sbin"
-    ln -s lib     "${workdir}/usr/lib64"
-}
-
-install_devmgr()
-{
-    print "installing device manager"
-
-    # false positive
-    # shellcheck disable=2016
-    case "$devmgr" in
-        none)
-            # TODO implement mode without device manager using deprecated
-            # /sys/kernel/uevent_helper or /proc/sys/kernel/hotplug
-        ;;
-        mdev)
-            for _binary in mdev find; do
-                install_binary "$_binary"
-            done
-
-            printf "%s\n" \
-                'SUBSYSTEM=block;.* 0:0 660 @device-helper' \
-            > "${workdir}/etc/mdev.conf"
-
-            [ "$monolith" = 1 ] && return 0
-
-            printf "%s\n" \
-                '$MODALIAS=.* 0:0 660 @modprobe "$MODALIAS"' \
-            >> "${workdir}/etc/mdev.conf"
-        ;;
-        mdevd)
-            for _binary in mdevd mdevd-coldplug; do
-                install_binary "$_binary"
-            done
-
-            printf "%s\n" \
-                'SUBSYSTEM=block;.* 0:0 660 @device-helper' \
-            > "${workdir}/etc/mdev.conf"
-
-            [ "$monolith" = 1 ] && return 0
-
-            printf "%s\n" \
-                '$MODALIAS=.* 0:0 660 @modprobe "$MODALIAS"' \
-            >> "${workdir}/etc/mdev.conf"
-        ;;
-        udev)
-            for _binary in udevd udevadm; do
-                install_binary "$_binary"
-            done
-
-            mkdir -p "${workdir}/usr/lib/udev/rules.d"
-
-            printf "%s\n" \
-                'SUBSYSTEMS=="block", ACTION=="add", RUN+="/bin/device-helper"' \
-            > "${workdir}/usr/lib/udev/rules.d/device-helper.rules"
-
-            [ "$monolith" = 1 ] && return 0
-
-            printf "%s\n" \
-                'ENV{MODALIAS}=="?*", ACTION=="add", RUN+="/bin/modprobe %E{MODALIAS}"' \
-            >> "${workdir}/usr/lib/udev/rules.d/device-helper.rules"
-        ;;
-    esac
-}
-
-install_lvm()
-{
-    print "installing LVM"
-
-    install_binary lvm
-
-    lvm_config="
-        devices {
-            write_cache_state = 0
-        }
-        backup {
-            backup  = 0
-            archive = 0
-        }
-        global {
-            use_lvmetad = 0
-        }"
-
-    # word splitting is safe by design
-    # shellcheck disable=2086
-    { IFS=,; set -- $lvm_opts; unset IFS; }
-
-    for opt; do case "$opt" in
-        config | config=1) embed_lvm_config=1 ;;
-    esac; done
-
-    mkdir -p "${workdir}/etc/lvm"
-
-    lvm config \
-        --config "$lvm_config" \
-        ${embed_lvm_config+--mergedconfig} \
-    > "${workdir}/etc/lvm/lvm.conf"
-
-    populate_config "lvm='$lvm'" "lvm_opts='$lvm_opts'"
-}
-
-install_luks()
-{
-    print "installing LUKS"
-
-    install_binary cryptsetup
-
-    # fix libgcc_s.so.1 missing error
-    # see https://bugs.archlinux.org/task/56771
-    [ -e /usr/lib/libgcc_s.so.1 ] &&
-        install_library /usr/lib/libgcc_s.so.1
-
-    # word splitting is safe by design
-    # shellcheck disable=2086
-    { IFS=,; set -- $luks_opts; unset IFS; }
-
-    for opt; do case "${opt%%=*}" in
-        key | header)
-            install -m400 "${opt##*=}" "${workdir}/root/${opt%%=*}" || panic
-            luks_opts=$(printf "%s" "$luks_opts" | sed "s|${opt##*=}|/root/${opt%%=*}|")
-        ;;
-    esac; done
-
-    populate_config \
-        "luks='$luks'" \
-        "luks_root='$luks_root'" \
-        "luks_opts='$luks_opts'"
-}
-
-install_module()
-{
-    module="$1"
-
-    modprobe -S "$kernel" -D "$module" 2> /dev/null |
-
-    while read -r module || [ "$module" ]; do
-
-        # skip unneeded stuff
-        for _exclude_module in wmi gpu net builtin $modules_exclude; do
-            case "$module" in *"$_exclude_module"*) continue 2 ;; esac
-        done
-
-        module="${module#insmod }"
-
-        # check if module already installed
-        [ -e "${workdir}${module}" ] && continue
-
-        install -Dm644 "$module" "${workdir}${module}" || panic
-    done
-}
-
-install_hostonly_modules()
-{
-    print "installing hostonly modules"
-
-    # perform autodetection of modules via /sys
-    find /sys -name modalias -exec sort -u {} + |
-
-    while read -r _module || [ "$_module" ]; do
-        install_module "$_module"
-    done
-
-    # install LVM modules
-    [ "$lvm" = 1 ] &&
-        for _module in dm-thin-pool dm-multipath \
-                       dm-snapshot dm-cache dm-log dm-mirror
     do
-            install_module "$_module"
+        copy_binary "$_binary"
     done
 
-    # install LUKS modules
+    # copy init
-    [ "$luks" = 1 ] &&
+    cp "${srcdir}/init" "${tmpdir}/init"
-        for _module in aes dm-crypt sha256 sha512 \
+    chmod 755           "${tmpdir}/init"
-                       wp512 ecb lrw xts twofish serpent
-        do
-            install_module "$_module"
-        done
 
-    # install root filesystem module
+    # copy config
-    if [ "$root_type" ]; then
+    cp "$config" "${tmpdir}/etc/tinyramfs/config"
-        install_module "$root_type"
+    chmod 600    "${tmpdir}/etc/tinyramfs/config"
-    else
-        while read -r _ _dir _type _; do
-            [ "$_dir" = / ] || continue
-
-            install_module "${root_type=$_type}"; break
-        done < /proc/mounts || panic
-    fi
 }
 
-install_all_modules()
+copy_binary()
-{
-    print "installing all modules"
-
-    find \
-        "${modker}/kernel/fs" \
-        "${modker}/kernel/lib" \
-        "${modker}/kernel/arch" \
-        "${modker}/kernel/crypto" \
-        "${modker}/kernel/drivers/md" \
-        "${modker}/kernel/drivers/ata" \
-        "${modker}/kernel/drivers/scsi" \
-        "${modker}/kernel/drivers/block" \
-        "${modker}/kernel/drivers/virtio" \
-        "${modker}/kernel/drivers/usb/host" \
-        "${modker}/kernel/drivers/usb/storage" \
-        -type f 2> /dev/null |
-
-    while read -r _module || [ "$_module" ]; do
-
-        # strip path and extension
-        _module="${_module##*/}"
-        _module="${_module%%.*}"
-
-        install_module "$_module"
-    done
-}
-
-install_modules()
-{
-    if [ "$hostonly" = 1 ]; then
-        install_hostonly_modules
-    else
-        install_all_modules
-    fi
-
-    # install user specified modules if any
-    [ "$modules" ] && {
-        for _module in $modules; do
-            install_module "$_module"
-        done; populate_config "modules='$modules'"
-    }
-
-    install_binary modprobe
-
-    install -m644 \
-        "${modker}/modules.builtin" \
-        "${modker}/modules.order" \
-        "${workdir}${modker}"
-
-    depmod -b "$workdir" "$kernel"
-}
-
-install_binary()
 {
     binary=$(command -v "$1")
 
     # check if binary exist and builtin
     case "$binary" in */*) ;;
         "")
-            panic "$1 doesn't exist"
+            panic "$1 does not exist"
         ;;
         *)
             # word splitting is safe by design
             # shellcheck disable=2086
-            { IFS=:; set -- $PATH; unset IFS; }
+            IFS=:; set -- $PATH; unset IFS
 
             # assume that `command -v` returned builtin command.
             # this behavior depends on shell implementation.
@@ -437,24 +163,27 @@ install_binary()
                 [ -x "${_dir}/${binary}" ] || ! continue
 
                 binary="${_dir}/${binary}"; break
-            done || panic "couldn't find external $1"
+            done || panic "$1 does not exist"
         ;;
     esac
 
-    # check if binary already installed
+    # check if binary already exist
-    [ -e "${workdirbin}${binary##*/}" ] && return 0
+    [ -e "${tmpdir}/bin/${binary##*/}" ] && return 0
 
     # iterate throught symlinks and copy them
-    while [ -h "$binary" ]; do
+    while [ -h "$binary" ]; do symlink=$(ls -ld "$binary")
-        cp -P "$binary" "$workdirbin" || panic
+        cp -P "$binary" "${tmpdir}/bin" || panic
-        readlink_binary=$(readlink "$binary")
+        binary="${binary%/*}/${symlink##* ->*[ /]}"
-        binary="${binary%/*}/${readlink_binary##*/}"
     done
 
-    install -m755 "$binary" "${workdirbin}${binary##*/}" || panic
+    {
-    strip "${workdirbin}${binary##*/}" > /dev/null 2>&1 || :
+        cp "$binary" "${tmpdir}/bin"
+        chmod 755    "${tmpdir}/bin/${binary##*/}"
+    } || panic
 
-    # install binary dependencies if any
+    strip "${tmpdir}/bin/${binary##*/}" > /dev/null 2>&1 || :
+
+    # copy binary dependencies if any
     ldd "$binary" 2> /dev/null |
 
     while read -r _library || [ "$_library" ]; do
@@ -465,44 +194,229 @@ install_binary()
         _library="${_library#* => }"
         _library="${_library% *}"
 
-        install_library "$_library"
+        copy_library "$_library"
     done
 }
 
-install_library()
+copy_library()
 {
     library="$1"
 
-    # check if library already installed
+    # check if library already exist
-    [ -e "${workdirlib}${library##*/}" ] && return 0
+    [ -e "${tmpdir}/lib/${library##*/}" ] && return 0
 
     # iterate throught symlinks and copy them
-    while [ -h "$library" ]; do
+    while [ -h "$library" ]; do symlink=$(ls -ld "$library")
-        cp -P "$library" "$workdirlib" || panic
+        cp -P "$library" "${tmpdir}/lib" || panic
-        readlink_library=$(readlink "$library")
+        library="${library%/*}/${symlink##* ->*[ /]}"
-        library="${library%/*}/${readlink_library##*/}"
     done
 
-    install -m755 "$library" "${workdirlib}${library##*/}" || panic
+    {
-    strip "${workdirlib}${library##*/}" > /dev/null 2>&1 || :
+        cp "$library" "${tmpdir}/lib"
+        chmod 755     "${tmpdir}/lib/${library##*/}"
+    } || panic
+
+    strip "${tmpdir}/lib/${library##*/}" > /dev/null 2>&1 || :
 }
 
-create_initramfs()
+copy_module()
+{
+    module="$1"
+
+    modprobe -S "$kernel" -D "$module" 2> /dev/null |
+
+    while read -r _ module || [ "$module" ]; do
+
+        # check if module contains full path(not builtin)
+        [ "${module##*/*}" ] && continue
+
+        # check if module already exist
+        [ -e "${tmpdir}${module}" ] && continue
+
+        {
+            mkdir -p     "${tmpdir}${module%/*}"
+            cp "$module" "${tmpdir}${module}"
+            chmod 644    "${tmpdir}${module}"
+        } || panic
+    done
+}
+
+copy_hook()
+{
+    hook="$1"
+
+    for _dir in "$hksdir" /etc/tinyramfs/hooks /usr/share/tinyramfs/hooks; do
+        [ -f "${_dir}/${hook}/${hook}" ] || ! continue
+
+        print "running $hook hook"; . "${_dir}/${hook}/${hook}"
+
+        if [ -f "${_dir}/${hook}/${hook}.init" ]; then
+            mkdir -p "${tmpdir}/usr/share/tinyramfs/hooks/${hook##*/}"
+            cp "${_dir}/${hook}/${hook}.init" \
+               "${tmpdir}/usr/share/tinyramfs/hooks/${hook##*/}"
+
+        elif [ -f "${_dir}/${hook}/${hook}.init.early" ]; then
+            mkdir -p "${tmpdir}/usr/share/tinyramfs/hooks/${hook##*/}"
+            cp "${_dir}/${hook}/${hook}.init.early" \
+               "${tmpdir}/usr/share/tinyramfs/hooks/${hook##*/}"
+        fi || panic
+
+        break
+    done || panic "could not run $hook"
+}
+
+copy_modules()
+{
+    # skip this function if kernel
+    # compiled with builtin modules
+    if [ "$monolith" = 1 ]; then
+        print "skipping modules"
+        return 0
+
+    elif [ "$hostonly" = 1 ]; then
+        print "copying hostonly modules"
+
+        # perform autodetection of modules via /sys
+        # see https://wiki.archlinux.org/index.php/Modalias
+        find /sys/devices -name modalias -exec sort -u {} + |
+
+        while read -r _module || [ "$_module" ]; do
+
+            # skip unneeded modules and skip modules which
+            # depends on them as well
+            case $(modprobe -S "$kernel" -D "$_module") in
+                *wmi* | *gpu* | *net*) continue ;;
+            esac 2> /dev/null
+
+            copy_module "$_module"
+        done
+
+        # copy root filesystem module
+        if [ "$root_type" ]; then
+            copy_module "$root_type"
+        else
+            while read -r _ _dir _type _; do
+                [ "$_dir" = / ] || ! continue
+
+                copy_module "$_type"; break
+            done < /proc/mounts ||
+            panic "could not copy root fs module"
+        fi
+    else
+        print "copying all modules"
+
+        find \
+            "${moddir}/${kernel}/kernel/fs" \
+            "${moddir}/${kernel}/kernel/lib" \
+            "${moddir}/${kernel}/kernel/arch" \
+            "${moddir}/${kernel}/kernel/crypto" \
+            "${moddir}/${kernel}/kernel/drivers/md" \
+            "${moddir}/${kernel}/kernel/drivers/ata" \
+            "${moddir}/${kernel}/kernel/drivers/scsi" \
+            "${moddir}/${kernel}/kernel/drivers/block" \
+            "${moddir}/${kernel}/kernel/drivers/virtio" \
+            "${moddir}/${kernel}/kernel/drivers/usb/host" \
+            "${moddir}/${kernel}/kernel/drivers/usb/storage" \
+            -type f 2> /dev/null |
+
+        while read -r _module || [ "$_module" ]; do
+
+            # strip path and extension
+            _module="${_module##*/}"
+            _module="${_module%%.*}"
+
+            # skip unneeded modules and skip modules which
+            # depends on them as well
+            case $(modprobe -S "$kernel" -D "$_module") in
+                *wmi* | *gpu* | *net*) continue ;;
+            esac 2> /dev/null
+
+            copy_module "$_module"
+        done
+    fi
+
+    copy_binary modprobe
+
+    cp "${moddir}/${kernel}/modules.builtin" \
+       "${moddir}/${kernel}/modules.order" \
+       "${tmpdir}${moddir}/${kernel}"
+
+    chmod 644 \
+        "${tmpdir}${moddir}/${kernel}/modules.builtin" \
+        "${tmpdir}${moddir}/${kernel}/modules.order"
+
+    depmod -b "$tmpdir" "$kernel"
+}
+
+copy_devmgr()
+{
+    print "configuring device manager"
+
+    # false positive
+    # shellcheck disable=2016
+    case "$devmgr" in
+        none)
+            # TODO implement mode without device manager using deprecated
+            # /sys/kernel/uevent_helper or /proc/sys/kernel/hotplug
+        ;;
+        mdev)
+            for _binary in mdev find; do
+                copy_binary "$_binary"
+            done
+
+            printf "%s\n" \
+                'SUBSYSTEM=block;.* 0:0 660 @device-helper' \
+            > "${tmpdir}/etc/mdev.conf"
+
+            [ "$monolith" = 1 ] || printf "%s\n" \
+                '$MODALIAS=.* 0:0 660 @modprobe "$MODALIAS"' \
+            >> "${tmpdir}/etc/mdev.conf"
+        ;;
+        mdevd)
+            for _binary in mdevd mdevd-coldplug; do
+                copy_binary "$_binary"
+            done
+
+            printf "%s\n" \
+                'SUBSYSTEM=block;.* 0:0 660 @device-helper' \
+            > "${tmpdir}/etc/mdev.conf"
+
+            [ "$monolith" = 1 ] || printf "%s\n" \
+                '$MODALIAS=.* 0:0 660 @modprobe "$MODALIAS"' \
+            >> "${tmpdir}/etc/mdev.conf"
+        ;;
+        udev)
+            # why systemd violates FHS and places daemon in /lib ?
+            udevd=$(command -v /lib/systemd/systemd-udevd) || udevd=udevd
+
+            for _binary in "$udevd" udevadm; do
+                copy_binary "$_binary"
+            done
+
+            mkdir -p "${tmpdir}/lib/udev/rules.d"
+
+            printf "%s\n" \
+                'SUBSYSTEMS=="block", ACTION=="add", RUN+="/bin/device-helper"' \
+            > "${tmpdir}/lib/udev/rules.d/device-helper.rules"
+
+            [ "$monolith" = 1 ] || printf "%s\n" \
+                'ENV{MODALIAS}=="?*", ACTION=="add", RUN+="/bin/modprobe %E{MODALIAS}"' \
+            >> "${tmpdir}/lib/udev/rules.d/device-helper.rules"
+        ;;
+    esac
+}
+
+make_initramfs()
 (
-    print "creating initramfs image"
+    print "generating initramfs image"
 
     # check if image already exist
     [ "$force" != 1 ] && [ -e "$output" ] &&
         panic "initramfs image already exist"
 
-    cd "$workdir"; find . |
+    cd "$tmpdir"; find . |
-
+    cpio -oH newc 2> /dev/null |
-    if [ "$compress" = none ]; then
+    ${compress:-cat} > "$output" ||
-        cpio -oH newc
-    else
-        cpio -oH newc | ${compress:-gzip -9}
-    fi \
-    > "$output" 2> /dev/null ||
     panic "failed to generate initramfs image"
 
     print "done! check out $output"
@@ -515,16 +429,15 @@ create_initramfs()
     # enable exit on error and disable globbing
     set -ef
 
-    parse_args "$@"
+    prepare_environment "$@"
-    prepare_environment
+    prepare_initramfs
-    create_structure
-    create_symlinks
 
-    [ "$lvm"      = 1 ] && install_lvm
+    # copy and run hooks if any
-    [ "$luks"     = 1 ] && install_luks
+    for _hook in $hooks; do
-    [ "$monolith" = 1 ] || install_modules
+        copy_hook "$_hook"
+    done
 
-    install_devmgr
+    copy_devmgr
-    install_requirements
+    copy_modules
-    create_initramfs
+    make_initramfs
 }