Refactor mkinitramfsHEADmaster

This does many little things. First, this changes the `function <name>`
syntax to `<name>()`. This also moves referencse from `echo` to
`printf`. It also switches out the bash `[[ ]]` conditional blocks to
more ubiquitous `[ ]`. This also simplifies the `get_first_path`
function (which will later be replaced as it is pretty bad).

Finally, this rewrites the `check_crypto_support` function. Rather than
copy in all of the kernel modules, then removing unneeded ones, it has
become easier to only copy what is needed, which further reduces the
initramfs size.

1 files changed, 65 insertions, 65 deletions

diff --git a/mkinitramfs b/mkinitramfs
index d38111d..2799838 100755
--- a/mkinitramfs
+++ b/mkinitramfs
@@ -31,18 +31,17 @@ declare -a fqbins
 #
 # @param bins All function arguments are the names of binaries to locate.
 #
-function resolve_bins {
+resolve_bins() {
   local args=${@}
+  local path=''
 
   for i in ${args[@]}; do
-    local path=$(type -p ${i} 2>/dev/null)
-
-    if [[ $? -gt 0 ]]; then
-      echo "Could not find binary ${i}. Is it installed?"
+    if ! path="$(type -p ${i} 2>/dev/null)"; then
+      printf 'Could not find binary %s. Is it installed?\n' "${i}"
       exit 1
     fi
 
-    echo "Located ${i} at ${path}"
+    printf 'Located %s at %s\n' "${i}" "${path}"
     fqbins+=("${path}")
   done
 }
@@ -51,34 +50,29 @@ function resolve_bins {
 #
 # Gets first path locatable in a string
 #
-function get_first_path {
-  local str=${1}
-
+get_first_path() {
+  local str="${1:-}"
   local out=''
-  local cursor=''
 
+  # Find the first occurrence of `/`
   for ((i=0; i<${#str}; i++)); do
-    if [[ ${str:$i:1} == '/' ]]; then
-      cursor=${i}
-      break
-    fi
+    [ "${str:$i:1}" = '/' ] && break
   done
 
   # Exit if no path found
-  [[ ${cursor} == '' ]] && return
+  [ "${i}" -eq "${#str}" ] && return 2
 
-  while [[ ${str:$cursor:1} != ' ' ]] && [[ ${cursor} -lt ${#str} ]]; do
-    out="${out}${str:$cursor:1}"
-    cursor=$((${cursor} + 1))
+  # Find end of string by looking for space
+  while [ "${str:$i:1}" != ' ' ] && [ "${i}" -lt "${#str}" ]; do
+    out="${out}${str:$i:1}"
+    (( i += 1 ))
   done
-
-  echo "${out}"
+  printf '%s\n' "${out}"
 }
 
 
-function get_deps {
-  local bin=${1}
-
+get_deps() {
+  local bin="${1:-}"
   for dep in $(ldd ${bin}); do
      get_first_path "${dep}"
   done
@@ -92,22 +86,22 @@ function get_deps {
 # @param cache   Path to the uncompressed source directory to be archived
 # @param version Version of initrd archive
 #
-function mkcpio {
-  [[ -z ${1} ]] && echo "Initramfs cache path required." && exit 1
-  [[ -z ${2} ]] && echo "Kernel version required." && exit 1
+mkcpio() {
+  [ -z "${1:-}" ] && printf 'Initramfs cache path required.\n' && exit 1
+  [ -z "${2:-}" ] && printf 'Kernel version required.\n' && exit 1
 
-  local cache=${1}
-  local version=${2}
+  local cache="${1}"
+  local version="${2}"
 
-  cd ${cache}
+  cd "${cache}"
   fspath="/boot/initrd-${version}"
 
   # Notify user of initrd overwriting
-  [[ -f ${fspath} ]] && echo -e "\n\n${fspath} exists. Overwriting.\n"
+  [ -f "${fspath}" ] && printf "\n\n%s exists. Overwriting.\n" "${fspath}"
 
   # Create the initrd
-  echo "Building initrd to ${fspath}"
-  find . -print0 | cpio --null -o --format=newc | xz -C crc32 -9 -c > ${fspath}
+  printf 'Building initrd to %s\n' "${fspath}"
+  find . -print0 | cpio --null -o --format=newc | xz -C crc32 -9 -c > "${fspath}"
 }
 
 
@@ -117,18 +111,16 @@ function mkcpio {
 #
 # @param cache Path to the cache directory. Will be created if not exists
 #
-function cache_dir_setup {
-  [[ -z ${1} ]] && echo "Please specify a cache dir." && exit 1
-  local cache=${1}
+cache_dir_setup() {
+  [ -z "${1}" ] && printf 'Please specify a cache dir.\n' && exit 1
+  local cache="${1:-}"
 
   # Clean the cache so we start fresh
-  rm -rf ${cache} && mkdir ${cache}
-
-  local dirs=(bin dev etc lib lib32 lib64 mnt/root proc root run sbin sys usr)
+  rm -r "${cache:?}" && mkdir "${cache}"
 
   # Create the temporary directory structure
-  for i in ${dirs[*]}; do
-    mkdir -p ${cache}/${i}
+  for i in bin dev etc lib lib32 lib64 mnt/root proc root run sbin sys usr/share; do
+    mkdir -p "${cache}/${i}"
   done
 
   # Copy in terminals database for `l` (linux - stock tty)
@@ -143,23 +135,31 @@ function cache_dir_setup {
 #
 # @param version Version of kernel modules to check
 #
-function check_crypto_support {
-  [[ -z ${1} ]] && echo "Kernel version required." && exit 1
-  local version=${1}
+check_crypto_support() {
+  [ -z "${1:-}" ] && printf 'Kernel version required.\n' && exit 1
+  local version="${1}"
   local buf=''
-
-  builtinpath=/lib/modules/${version}/modules.builtin
-
-  mkdir -p ${cache}/lib/modules/
-  cp -vr "/lib/modules/${version}/" "${cache}/lib/modules/${version}"
-
-  # Strip out kernel modules not required for bootstrapping
-  for i in virt sound drivers/{bluetooth,gpu,hid,media,mmc,net,video,virtio}; do
-    buf="${cache}/lib/modules/${version}/kernel/${i}"
-    if [ -d "${buf}" ]; then
-      printf 'Stripping %s from initramfs\n' "${buf}"
-      rm -r "${buf:?}"
-    fi
+  local -a copy=(
+    arch/x86/crypto
+    crypto
+    drivers/input/{keyboard,serio,*.ko}
+    drivers/{crypto,usb,platform,md}
+    lib
+    fs/{btrfs,xfs,ext4}
+  )
+
+  mkdir -p "${cache}/lib/modules/${version}"
+  cp -v /lib/modules/${version}/modules*.bin "${cache}/lib/modules/${version}/"
+
+  # Copy in all the rewuired kernel modules
+  for i in ${copy[@]}; do
+    buf=(/lib/modules/${version}/kernel/${i})
+    # For globbing in the array
+    for ent in ${buf[@]}; do
+      printf 'Copying in %s\n' "${ent}"
+      mkdir -p "$(dirname ${cache}/${ent})"
+      cp -r "${ent}" "${cache}/${ent}"
+    done
   done
 }
 
@@ -170,21 +170,21 @@ function check_crypto_support {
 #
 # @param version Version to check for installation status
 #
-function check_kernel_version {
-  [[ -z ${1} ]] && echo "Kernel version required." && exit 1
-  local version=${1}
+check_kernel_version() {
+  [ -z ${1} ] && printf 'Kernel version required.\n' && exit 1
+  local version="${1}"
+  local modulespath="/lib/modules/${version}"
 
-  modulespath=/lib/modules/${version}
-  if [[ ! -d ${modulespath} ]]; then
-    echo "Error: Could not find ${modulespath}."
-    echo "Has kernel version ${version} been comiled?"
+  if [ ! -d ${modulespath} ]; then
+    printf 'Error: Could not find %s.\n' "${modulespath}"
+    printf 'Has kernel version %s been comiled?' "${version}"
     exit 1
   fi
 }
 
 
-function main {
-  [[ -z ${1} ]] && echo "Please specify a kernel version" && exit 1
+main() {
+  [ -z "${1:-}" ] && printf 'Please specify a kernel version\n' && exit 1
 
   local version=${1}