zfsbootmenu: refactor installation, support system and user runtime hooks

- All core components, docs and runtime hooks are handled by a common
  install_helper that is aware of both dracut and mkinitcpio methods

- Installation now adds "system" runtime hooks in addition to those
  configured by the user; user hooks with names that conflict with
  system hooks will "mask" the system version

- The hooks `10-console-init.sh` and `xhci-teardown.sh` have been
  elevated to "system" status and are always installed in ZBM images

- The `zfsbootmenu/hook` path has been renamed to `zfsbootmenu/pre-init`
  to avoid confusion with the new `zfsbootmenu/hooks` directory of
  system runtime hooks, and the dracut-only `hook` scripts have been
  moved to the dracut module

- A new `zbm.skip_hooks` command-line argument allows a comma-separated
  list of hooks to skip (matched on basename only) to provide an easy
  mechanism for skipping default hooks without `zbm.hookroot`

- Create the `zfsbootmenu-run-hooks` libexec helper, allowing easy
  addition of future hook points.

Co-authored-by: Zach Dykstra <dykstra.zachary@gmail.org>
Co-authored-by: Andrew J. Hesford <ajh@sideband.org>

docs/man/zfsbootmenu.7.rst

@@ -133,6 +133,12 @@ These options are set on the kernel command line when booting the initramfs or U
 
     zbm.kcl_override="some alternate set='of arguments'"
 
+**zbm.skip_hooks=<hooklist>**
+
+  Skip execution of any early-setup, setup or teardown hooks with file names matching any entry in the comma-separated list *hooklist*. Only base names of hooks (*i.e.*, with any other path component removed) are matched against the *hooklist*.
+
+  **NOTE**: The *hooklist* argument **MUST NOT** contain spaces and **MUST NOT** be enclosed in quotes.
+
 Deprecated Command-Line Parameters
 ==================================
 

dracut/module-setup.sh

@@ -40,8 +40,9 @@ install() {
   # BUILDROOT is an initcpio-ism
   # shellcheck disable=SC2154,2034
   BUILDROOT="${initdir}"
+
   # shellcheck disable=SC2034
-  BUILDSTYLE="dracut"
+  ZBM_BUILDSTYLE="dracut"
 
   local _rule _exec _ret
 
@@ -84,90 +85,43 @@ install() {
     fi
   done <<< "${_libgcc_s}"
 
-  # shellcheck disable=SC2154
-  while read -r doc ; do
-    relative="${doc//${zfsbootmenu_module_root}\//}"
-    inst_simple "${doc}" "/usr/share/docs/${relative}"
-  done <<<"$( find "${zfsbootmenu_module_root}/help-files" -type f )"
-
   compat_dirs=( "/etc/zfs/compatibility.d" "/usr/share/zfs/compatibility.d/" )
   for compat_dir in "${compat_dirs[@]}"; do
     # shellcheck disable=2164
     [ -d "${compat_dir}" ] && tar -cf - "${compat_dir}" | ( cd "${initdir}" ; tar xfp - )
   done
+
   _ret=0
 
-  # Core ZFSBootMenu functionality
-  # shellcheck disable=SC2154
-  for _lib in "${zfsbootmenu_module_root}"/lib/*; do
-    inst_simple "${_lib}" "/lib/$( basename "${_lib}" )" || _ret=$?
-  done
+  # Install core ZFSBootMenu functionality
+  install_zbm_core || _ret=$?
 
-  # Helper tools not intended for direct human consumption
-  for _libexec in "${zfsbootmenu_module_root}"/libexec/*; do
-    inst_simple "${_libexec}" "/libexec/$( basename "${_libexec}" )" || _ret=$?
-  done
-
-  # User-facing utilities, useful for running in a recovery shell
-  for _bin in "${zfsbootmenu_module_root}"/bin/*; do
-    inst_simple "${_bin}" "/bin/$( basename "${_bin}" )" || _ret=$?
-  done
+  # Install runtime hooks
+  install_zbm_hooks || _ret=$?
 
   # Hooks necessary to initialize ZBM
-  inst_hook cmdline 95 "${zfsbootmenu_module_root}/hook/zfsbootmenu-parse-commandline.sh" || _ret=$?
-  inst_hook pre-mount 90 "${zfsbootmenu_module_root}/hook/zfsbootmenu-preinit.sh" || _ret=$?
+  inst_hook cmdline 95 "${zfsbootmenu_module_root}/pre-init/zfsbootmenu-parse-commandline.sh" || _ret=$?
+  inst_hook pre-mount 90 "${zfsbootmenu_module_root}/pre-init/zfsbootmenu-preinit.sh" || _ret=$?
 
   # Hooks to force the dracut event loop to fire at least once
   # Things like console configuration are done in optional event-loop hooks
-  inst_hook initqueue/settled 99 "${zfsbootmenu_module_root}/hook/zfsbootmenu-ready-set.sh" || _ret=$?
-  inst_hook initqueue/finished 99 "${zfsbootmenu_module_root}/hook/zfsbootmenu-ready-chk.sh" || _ret=$?
-
-  # optionally enable early Dracut profiling
-  if [ -n "${dracut_trace_enable}" ]; then
-    inst_hook cmdline 00 "${zfsbootmenu_module_root}/profiling/profiling-lib.sh"
-  fi
-
-  # Install "early setup" hooks
   # shellcheck disable=SC2154
-  if [ -n "${zfsbootmenu_early_setup}" ]; then
-    for _exec in ${zfsbootmenu_early_setup}; do
-      if [ -x "${_exec}" ]; then
-        inst_simple "${_exec}" "/libexec/early-setup.d/$(basename "${_exec}")" || _ret=$?
-      else
-        dwarning "setup script (${_exec}) missing or not executable; cannot install"
-      fi
-    done
-  fi
-
-  # Install "setup" hooks
-  # shellcheck disable=SC2154
-  if [ -n "${zfsbootmenu_setup}" ]; then
-    for _exec in ${zfsbootmenu_setup}; do
-      if [ -x "${_exec}" ]; then
-        inst_simple "${_exec}" "/libexec/setup.d/$(basename "${_exec}")" || _ret=$?
-      else
-        dwarning "setup script (${_exec}) missing or not executable; cannot install"
-      fi
-    done
-  fi
-
-  # Install "teardown" hooks
-  # shellcheck disable=SC2154
-  if [ -n "${zfsbootmenu_teardown}" ]; then
-    for _exec in ${zfsbootmenu_teardown}; do
-      if [ -x "${_exec}" ]; then
-        inst_simple "${_exec}" "/libexec/teardown.d/$(basename "${_exec}")" || _ret=$?
-      else
-        dwarning "teardown script (${_exec}) missing or not executable; cannot install"
-      fi
-    done
-  fi
+  inst_hook initqueue/settled 99 "${moddir}/zfsbootmenu-ready-set.sh" || _ret=$?
+  inst_hook initqueue/finished 99 "${moddir}/zfsbootmenu-ready-chk.sh" || _ret=$?
 
   if [ ${_ret} -ne 0 ]; then
     dfatal "Unable to install core ZFSBootMenu functions"
     exit 1
   fi
 
+  # Install online documentation if possible
+  install_zbm_docs
+
+  # optionally enable early Dracut profiling
+  if [ -n "${dracut_trace_enable}" ]; then
+    inst_hook cmdline 00 "${zfsbootmenu_module_root}/profiling/profiling-lib.sh"
+  fi
+
   # vdev_id.conf and hostid files are host-specific
   # and do not belong in public release images
   if [ -z "${release_build}" ]; then

etc/zfsbootmenu/release.conf.d/common.conf

@@ -1,5 +1,4 @@
-zfsbootmenu_teardown+=" /zbm/contrib/xhci-teardown.sh "
-zfsbootmenu_early_setup+=" /zbm/contrib/10-console-init.sh /zbm/contrib/20-console-autosize.sh "
+zfsbootmenu_early_setup+=" /zbm/contrib/20-console-autosize.sh "
 
 # zbm-kcl
 install_optional_items+=" /zbm/bin/zbm-kcl "

initcpio/install/zfsbootmenu

@@ -122,7 +122,7 @@ build() {
     source "${zfsbootmenu_module_root}/install-helpers.sh" || exit 1
 
     # shellcheck disable=SC2034
-    BUILDSTYLE="initcpio"
+    ZBM_BUILDSTYLE="mkinitcpio"
 
     # Modules (required and optional) used by ZBM
     # shellcheck disable=SC2154
@@ -154,52 +154,32 @@ build() {
         fi
     done <<< "${_libgcc_s}"
 
-    # On-line documentation
-    while read -r doc; do
-        relative="${doc#"${zfsbootmenu_module_root}/"}"
-        [ "${relative}" = "${doc}" ] && continue
-        add_file "${doc}" "/usr/share/docs/${relative}"
-    done <<< "$( find "${zfsbootmenu_module_root}/help-files" -type f )"
-
     # Install core ZBM functionality
-    for _file in "${zfsbootmenu_module_root}"/lib/*; do
-        add_file "${_file}" "/lib/${_file##*/}"
-    done
+    if ! install_zbm_core; then
+        error "Failed to install ZFSBootMenu core"
+        exit 1
+    fi
 
-    for _file in "${zfsbootmenu_module_root}"/libexec/*; do
-        add_file "${_file}" "/libexec/${_file##*/}"
-    done
+    # Install runtime hooks
+    if ! install_zbm_hooks; then
+        error "Failed to install runtime hooks"
+        exit 1
+    fi
 
-    for _file in "${zfsbootmenu_module_root}"/bin/*; do
-        add_file "${_file}" "/bin/${_file##*/}"
-    done
+    # Install online documentation if possible
+    install_zbm_docs
 
-    hooks=( zfsbootmenu-{parse-commandline,preinit}.sh )
-    for _file in "${hooks[@]}"; do
-        add_file "${zfsbootmenu_module_root}/hook/${_file}" "/lib/${_file}"
+    # Install pre-init scripts
+    for _file in "${zfsbootmenu_module_root}"/pre-init/*; do
+        add_file "${_file}" "/lib/${_file##*/}" && continue;
+
+        error "Failed to install ZFSBootMenu component ${_file}"
+        exit 1
     done
 
     # allow mount(8) to "autodetect" ZFS
     echo 'zfs' >>"${BUILDROOT}/etc/filesystems"
 
-    # shellcheck disable=SC2154
-    for _file in "${zfsbootmenu_early_setup[@]}"; do
-        [ -x "${_file}" ] || continue
-        add_file "${_file}" "/libexec/early-setup.d/${_file##*/}"
-    done
-
-    # shellcheck disable=SC2154
-    for _file in "${zfsbootmenu_setup[@]}"; do
-        [ -x "${_file}" ] || continue
-        add_file "${_file}" "/libexec/setup.d/${_file##*/}"
-    done
-
-    # shellcheck disable=SC2154
-    for _file in "${zfsbootmenu_teardown[@]}"; do
-        [ -x "${_file}" ] || continue
-        add_file "${_file}" "/libexec/teardown.d/${_file##*/}"
-    done
-
     compat_dirs=( "/etc/zfs/compatibility.d" "/usr/share/zfs/compatibility.d/" )
     for compat_dir in "${compat_dirs[@]}"; do
         [ -d "${compat_dir}" ] && add_full_dir "${compat_dir}"

zfsbootmenu/bin/zfsbootmenu

@@ -68,14 +68,8 @@ if [ -r "${BASE}/bootfs" ]; then
 fi
 
 # Run setup hooks, if they exist
-if [ -d /libexec/setup.d ]; then
-  tput clear
-  for _hook in /libexec/setup.d/*; do
-    zinfo "Processing hook: ${_hook}"
-    [ -x "${_hook}" ] && "${_hook}"
-  done
-  unset _hook
-fi
+tput clear
+/libexec/zfsbootmenu-run-hooks "setup.d"
 
 # Clear screen before a possible password prompt
 tput clear

zfsbootmenu/hooks/early-setup.d/10-console-init.sh

@@ -6,6 +6,10 @@
 ## which causes the normal dracut initqueue to be thrown out; the ZFSBootMenu
 ## initqueue hooks that force the dracut event loop to run at least once are
 ## purged, so dracut terminates the event loop before console initialization.
+##
+
+# There is nothing to do if we're not in dracut
+[ "${ZBM_BUILDSTYLE,,}" = "dracut" ] || exit 0
 
 # There is nothing to do if the console initializer is not executable
 [ -x /lib/udev/console_init ] || exit 0

zfsbootmenu/install-helpers.sh

@@ -100,6 +100,13 @@ create_zbm_conf() {
     has_column=1
   fi
 
+  # Normalize ZBM_BUILDSTYLE, if set
+  case "${ZBM_BUILDSTYLE,,}" in
+    mkinitcpio) ZBM_BUILDSTYLE="mkinitcpio" ;;
+    dracut) ZBM_BUILDSTYLE="dracut" ;;
+    *) ZBM_BUILDSTYLE="" ;;
+  esac
+
   cat > "${BUILDROOT}/etc/zfsbootmenu.conf" <<-'EOF'
 	# Include guard
 	[ -n "${_ETC_ZFSBOOTMENU_CONF}" ] && return
@@ -111,6 +118,7 @@ create_zbm_conf() {
 	export HAS_DISABLED="${has_disabled}"
 	export HAS_BORDER="${has_border}"
 	export HAS_COLUMN="${has_column}"
+	export ZBM_BUILDSTYLE="${ZBM_BUILDSTYLE}"
 	EOF
 }
 
@@ -149,6 +157,27 @@ create_zbm_profiles() {
   ln -s "/root/.bashrc" "${BUILDROOT}/root/.profile"
 }
 
+zbm_install_file() {
+  case "${ZBM_BUILDSTYLE,,}" in
+    mkinitcpio)
+      if ! add_file "${1}" "${2}"; then
+        error "failed to install file '${1}'"
+        return 1
+      fi
+      ;;
+    dracut)
+      if ! inst_simple "${1}" "${2}"; then
+        dfatal "failed to install file '${1}'"
+        return 1
+      fi
+      ;;
+    *)
+      echo "ERROR: unrecognized build style; unable to install files" >&2
+      return 1
+      ;;
+  esac
+}
+
 create_zbm_traceconf() {
   local zbm_prof_lib
 
@@ -167,16 +196,7 @@ create_zbm_traceconf() {
     return
   fi
 
-  case "${BUILDSTYLE}" in
-    initcpio)
-      add_file "${zbm_prof_lib}" "/lib/profiling-lib.sh"
-      ;;
-    dracut)
-      inst_simple "${zfsbootmenu_module_root}/profiling/profiling-lib.sh" "/lib/profiling-lib.sh"
-      ;;
-    *)
-      ;;
-  esac
+  zbm_install_file "${zbm_prof_lib}" "/lib/profiling-lib.sh"
 
   # shellcheck disable=SC2154
   cat > "${BUILDROOT}/etc/profiling.conf" <<-EOF
@@ -185,6 +205,101 @@ create_zbm_traceconf() {
 	EOF
 }
 
+
+install_zbm_core() {
+  local cdir cfile ret
+
+  ret=0
+  for cdir in lib libexec bin; do
+    for cfile in "${zfsbootmenu_module_root}/${cdir}"/*; do
+      zbm_install_file "${cfile}" "/${cdir}/${cfile##*/}" || ret=$?
+    done
+  done
+
+  return $ret
+}
+
+
+install_zbm_docs() {
+  local doc relative ret
+
+  ret=0
+  while read -r doc; do
+    relative="${doc#"${zfsbootmenu_module_root}"}"
+    [ "${relative}" = "${doc}" ] && continue
+    relative="${relative#/}"
+    zbm_install_file "${doc}" "/usr/share/docs/${relative}" || ret=$?
+  done <<< "$( find "${zfsbootmenu_module_root}/help-files" -type f )"
+
+  return $ret
+}
+
+
+populate_hook_dir() {
+  local hfile ret hlev
+
+  hlev="${1}"
+  if [ -z "${hlev}" ]; then
+    echo "ERROR: a hook level is required" >&2
+    return 1
+  fi
+
+  shift
+  [ "$#" -gt 0 ] || return 0
+
+  mkdir -p "${BUILDROOT}/libexec/${hlev}" || return 1
+
+  ret=0
+  for hfile in "$@"; do
+    [ -x "${hfile}" ] || continue
+    zbm_install_file "${hfile}" "/libexec/${hlev}/${hfile##*/}" || ret=$?
+  done
+
+  return $ret
+}
+
+
+install_zbm_hooks() {
+  local hdir hsrc hfile ret
+
+  ret=0
+
+  # Install system hooks first
+  for hdir in early-setup.d setup.d teardown.d; do
+    hsrc="${zfsbootmenu_module_root}/hooks/${hdir}"
+    [ -d "${hsrc}" ] || continue
+    populate_hook_dir "${hdir}" "${hsrc}"/* || ret=$?
+  done
+
+  # Next, install user hooks to allow them to override system versions
+  # shellcheck disable=SC2154
+  if [[ "${zfsbootmenu_early_setup@a}" != *a* ]]; then
+    # shellcheck disable=SC2086
+    populate_hook_dir "early-setup.d" ${zfsbootmenu_early_setup} || ret=$?
+  else
+    populate_hook_dir "early-setup.d" "${zfsbootmenu_early_setup[@]}" || ret=$?
+  fi
+
+  # shellcheck disable=SC2154
+  if [[ "${zfsbootmenu_setup@a}" != *a* ]]; then
+    # shellcheck disable=SC2086
+    populate_hook_dir "setup.d" ${zfsbootmenu_setup} || ret=$?
+  else
+    populate_hook_dir "setup.d" "${zfsbootmenu_setup[@]}" || ret=$?
+  fi
+
+  # shellcheck disable=SC2154
+  if [[ "${zfsbootmenu_teardown@a}" != *a* ]]; then
+    # shellcheck disable=SC2086
+    populate_hook_dir "teardown.d" ${zfsbootmenu_teardown} || ret=$?
+  else
+    populate_hook_dir "teardown.d" "${zfsbootmenu_teardown[@]}" || ret=$?
+  fi
+
+  return $ret
+}
+
+
 find_libgcc_s() {
   local f libdirs libbase ldir zlibs matched
 

zfsbootmenu/lib/zfsbootmenu-core.sh

@@ -273,7 +273,7 @@ mount_zfs() {
 # returns: 1 on error, otherwise does not return
 
 kexec_kernel() {
-  local selected fs kernel initramfs tdhook output
+  local selected fs kernel initramfs output
 
   selected="${1}"
   if [ -z "${selected}" ]; then
@@ -332,15 +332,10 @@ kexec_kernel() {
   done <<<"$( zpool list -H -o name )"
 
   # Run teardown hooks, if they exist
-  if [ -d /libexec/teardown.d ]; then
-    for tdhook in /libexec/teardown.d/*; do
-      [ -x "${tdhook}" ] || continue
-      zinfo "Processing hook: ${tdhook}"
-      env "ZBM_SELECTED_INITRAMFS=${initramfs}" \
-        "ZBM_SELECTED_KERNEL=${kernel}" "ZBM_SELECTED_BE=${fs}" "${tdhook}"
-    done
-    unset tdhook
-  fi
+  env "ZBM_SELECTED_INITRAMFS=${initramfs}" \
+    "ZBM_SELECTED_KERNEL=${kernel}" \
+    "ZBM_SELECTED_BE=${fs}" \
+    /libexec/zfsbootmenu-run-hooks "teardown.d"
 
   if ! output="$( kexec -e -i 2>&1 )"; then
     zerror "kexec -e -i failed!"

zfsbootmenu/libexec/zfsbootmenu-init

@@ -83,16 +83,28 @@ if [ -n "${zbm_hook_root}" ]; then
   import_zbm_hooks "${zbm_hook_root}"
 fi
 
-# Run early setup hooks, if they exist
-if [ -d /libexec/early-setup.d ]; then
-  tput clear
-  for _hook in /libexec/early-setup.d/*; do
-    zinfo "Processing hook: ${_hook}"
-    [ -x "${_hook}" ] && "${_hook}"
+# Remove the executable bit from any hooks in the skip list
+if zbm_skip_hooks="$( get_zbm_arg zbm.skip_hooks )" && [ -n "${zbm_skip_hooks}" ]; then
+  zdebug "processing hook skip directives: ${zbm_skip_hooks}"
+  IFS=',' read -r -a zbm_skip_hooks <<<"${zbm_skip_hooks}"
+  for _skip in "${zbm_skip_hooks[@]}"; do
+    [ -n "${_skip}" ] || continue
+
+    for _hook in /libexec/{early-setup,setup,teardown}.d/*; do
+      [ -e "${_hook}" ] || continue
+      if [ "${_skip}" = "${_hook##*/}" ]; then
+        zinfo "Disabling hook: ${_hook}"
+        chmod 000 "${_hook}"
+      fi
+    done
   done
-  unset _hook
+  unset _hook _skip
 fi
 
+# Run early setup hooks, if they exist
+tput clear
+/libexec/zfsbootmenu-run-hooks "early-setup.d"
+
 # Prefer a specific pool when checking for a bootfs value
 # shellcheck disable=SC2154
 if [ "${root}" = "zfsbootmenu" ]; then

zfsbootmenu/libexec/zfsbootmenu-run-hooks

@@ -0,0 +1,31 @@
+#!/bin/bash
+# vim: softtabstop=2 shiftwidth=2 expandtab
+
+# shellcheck disable=SC1091
+
+sources=(
+  /lib/profiling-lib.sh
+  /etc/zfsbootmenu.conf
+  /lib/kmsg-log-lib.sh
+)
+
+for src in "${sources[@]}"; do
+  # shellcheck disable=SC1090
+  source "${src}" >/dev/null 2>&1 || exit 1
+done
+
+hook_stage="${1}"
+
+if [ -z "${hook_stage}" ]; then
+  zerror "required hook stage undefined"
+  exit 1
+fi
+
+if [ -d "/libexec/${hook_stage}" ]; then
+  for _hook in /libexec/"${hook_stage}"/*; do
+    if [ -x "${_hook}" ]; then
+      zinfo "processing ${_hook}"
+      "${_hook}"
+    fi
+  done
+fi