tree-wide: fix shellcheck warnings and style consistency

arch-chroot.in

@@ -2,27 +2,30 @@
 
 shopt -s extglob
 
+# m4_include() is recognized as a function definition
+# shellcheck source=common disable=SC1073,SC1065,SC1064,SC1072
 m4_include(common)
 
 setup=chroot_setup
 unshare=0
+userspec=''
+chroot_args=()
 
 usage() {
   cat <<EOF
-usage: ${0##*/} chroot-dir [command] [arguments...]
+usage: ${0##*/} [options] chroot_dir [command [arguments...]]
 
-    -h                  Print this help message
+  Options:
     -N                  Run in unshare mode as a regular user
-    -u <user>[:group]   Specify non-root user and optional group to use
+    -u <user>[:group]   Specify non-root user and group (optional) to use
-
+    -h                  Print this help message
-If 'command' is unspecified, ${0##*/} will launch /bin/bash.
+If 'command' is unspecified, arch-chroot will launch /bin/bash.
 
 Note that when using arch-chroot, the target chroot directory *should* be a
 mountpoint. This ensures that tools such as pacman(8) or findmnt(8) have an
 accurate hierarchy of the mounted filesystems within the chroot.
-
 If your chroot target is not a mountpoint, you can bind mount the directory on
-itself to make it a mountpoint, i.e. 'mount --bind /your/chroot /your/chroot'.
+itself to make it one, i.e. 'mount --bind chroot_dir chroot_dir'.
 
 EOF
 }
@@ -74,32 +77,32 @@ chroot_add_resolv_conf() {
   chroot_add_mount "$src" "$dest" --bind
 }
 
-while getopts ':hNu:' flag; do
+if [[ -z $1 || $1 = @(-h|--help) ]]; then
-  case $flag in
-    h)
   usage
-      exit 0
+  exit $(( $# ? 0 : 1 ))
-      ;;
+fi
+
+while getopts ':Nu:' flag; do
+  case $flag in
     N)
       setup=unshare_setup
       unshare=1
       ;;
     u)
-      userspec=$OPTARG
+      userspec="$OPTARG"
       ;;
     :)
-      die '%s: option requires an argument -- '\''%s'\' "${0##*/}" "$OPTARG"
+      die "%s: option requires an argument -- '%s'" "${0##*/}" "$OPTARG"
       ;;
     ?)
-      die '%s: invalid option -- '\''%s'\' "${0##*/}" "$OPTARG"
+      die "%s: invalid option -- '%s'" "${0##*/}" "$OPTARG"
       ;;
   esac
 done
 shift $(( OPTIND - 1 ))
 
 (( $# )) || die 'No chroot directory specified'
-chrootdir=$1
+chrootdir="$1"; shift
-shift
 
 arch-chroot() {
   (( EUID == 0 )) || die 'This script must be run with root privileges'
@@ -125,3 +128,5 @@ if (( unshare )); then
 else
   arch-chroot
 fi
+
+# vim: et ts=2 sw=2 ft=sh:

common

@@ -1,3 +1,6 @@
+#!/hint/bash
+# shellcheck disable=SC2155,SC2064
+
 # generated from util-linux source: libmount/src/utils.c
 declare -A pseudofs_types=([anon_inodefs]=1
                            [apparmorfs]=1
@@ -72,11 +75,12 @@ declare -A fsck_types=([btrfs]=0    # btrfs doesn't need a regular fsck utility
                        [vfat]=1
                        [xfs]=1)
 
+# shellcheck disable=SC2059
 out() { printf "$1 $2\n" "${@:3}"; }
-error() { out "==> ERROR:" "$@"; } >&2
-warning() { out "==> WARNING:" "$@"; } >&2
 msg() { out "==>" "$@"; }
-msg2() { out "  ->" "$@";}
+msg2() { out "  ->" "$@"; }
+warning() { out "==> WARNING:" "$@"; } >&2
+error() { out "==> ERROR:" "$@"; } >&2
 die() { error "$@"; exit 1; }
 
 ignore_error() {
@@ -86,23 +90,44 @@ ignore_error() {
 
 in_array() {
   local i
+
   for i in "${@:2}"; do
-    [[ $1 = "$i" ]] && return 0
+    [[ "$1" = "$i" ]] && return 0
   done
   return 1
 }
 
+rev_array() {
+  local -n _arr="$1"
+
+  mapfile -t _arr < <(printf '%s\n' "${_arr[@]}" | tac)
+}
+
 chroot_add_mount() {
-  mount "$@" && CHROOT_ACTIVE_MOUNTS=("$2" "${CHROOT_ACTIVE_MOUNTS[@]}")
+  mount "$@" && CHROOT_ACTIVE_MOUNTS+=("$2")
 }
 
 chroot_maybe_add_mount() {
-  local cond=$1; shift
+  local cond="$1"; shift
+
   if eval "$cond"; then
     chroot_add_mount "$@"
   fi
 }
 
+chroot_add_mount_lazy() {
+  mount "$@" && CHROOT_ACTIVE_LAZY+=("$2")
+}
+
+chroot_bind_device() {
+  touch "$2" && CHROOT_ACTIVE_FILES+=("$2")
+  chroot_add_mount "$1" "$2" --bind
+}
+
+chroot_add_link() {
+  ln -sf "$1" "$2" && CHROOT_ACTIVE_FILES+=("$2")
+}
+
 chroot_setup() {
   CHROOT_ACTIVE_MOUNTS=()
   [[ $(trap -p EXIT) ]] && die '(BUG): attempting to overwrite existing EXIT trap'
@@ -121,28 +146,14 @@ chroot_setup() {
 
 chroot_teardown() {
   if (( ${#CHROOT_ACTIVE_MOUNTS[@]} )); then
+    rev_array CHROOT_ACTIVE_MOUNTS
     umount "${CHROOT_ACTIVE_MOUNTS[@]}"
   fi
   unset CHROOT_ACTIVE_MOUNTS
 }
 
-chroot_add_mount_lazy() {
-  mount "$@" && CHROOT_ACTIVE_LAZY=("$2" "${CHROOT_ACTIVE_LAZY[@]}")
-}
-
-chroot_bind_device() {
-  touch "$2" && CHROOT_ACTIVE_FILES=("$2" "${CHROOT_ACTIVE_FILES[@]}")
-  chroot_add_mount $1 "$2" --bind
-}
-
-chroot_add_link() {
-  ln -sf "$1" "$2" && CHROOT_ACTIVE_FILES=("$2" "${CHROOT_ACTIVE_FILES[@]}")
-}
-
 unshare_setup() {
-  CHROOT_ACTIVE_MOUNTS=()
+  CHROOT_ACTIVE_MOUNTS=() CHROOT_ACTIVE_LAZY=() CHROOT_ACTIVE_FILES=()
-  CHROOT_ACTIVE_LAZY=()
-  CHROOT_ACTIVE_FILES=()
   [[ $(trap -p EXIT) ]] && die '(BUG): attempting to overwrite existing EXIT trap'
   trap 'unshare_teardown' EXIT
 
@@ -167,17 +178,20 @@ unshare_teardown() {
   chroot_teardown
 
   if (( ${#CHROOT_ACTIVE_LAZY[@]} )); then
+    rev_array CHROOT_ACTIVE_LAZY
     umount --lazy "${CHROOT_ACTIVE_LAZY[@]}"
   fi
   unset CHROOT_ACTIVE_LAZY
 
   if (( ${#CHROOT_ACTIVE_FILES[@]} )); then
+    rev_array CHROOT_ACTIVE_FILES
     rm "${CHROOT_ACTIVE_FILES[@]}"
   fi
   unset CHROOT_ACTIVE_FILES
 }
 
 pid_unshare="unshare --fork --pid"
+# shellcheck disable=SC2034
 mount_unshare="$pid_unshare --mount --map-auto --map-root-user --setuid 0 --setgid 0"
 
 # This outputs code for declaring all variables to stdout. For example, if
@@ -198,11 +212,11 @@ declare_all() {
 }
 
 try_cast() (
-  _=$(( $1#$2 ))
+  _=$(( ${1#"$2"} ))
 ) 2>/dev/null
 
 valid_number_of_base() {
-  local base=$1 len=${#2} i=
+  local base="$1" len="${#2}" i
 
   for (( i = 0; i < len; i++ )); do
     try_cast "$base" "${2:i:1}" || return 1
@@ -212,29 +226,29 @@ valid_number_of_base() {
 }
 
 mangle() {
-  local i= chr= out=
+  local i chr out
-  local {a..f}= {A..F}=
+  local {a..f}='' {A..F}=''
 
   for (( i = 0; i < ${#1}; i++ )); do
-    chr=${1:i:1}
+    chr="${1:i:1}"
     case $chr in
       [[:space:]\\])
         printf -v chr '%03o' "'$chr"
         out+=\\
         ;;
     esac
-    out+=$chr
+    out+="$chr"
   done
 
   printf '%s' "$out"
 }
 
 unmangle() {
-  local i= chr= out= len=$(( ${#1} - 4 ))
+  local i chr out len="$(( ${#1} - 4 ))"
-  local {a..f}= {A..F}=
+  local {a..f}='' {A..F}=''
 
   for (( i = 0; i < len; i++ )); do
-    chr=${1:i:1}
+    chr="${1:i:1}"
     case $chr in
       \\)
         if valid_number_of_base 8 "${1:i+1:3}" ||
@@ -244,7 +258,7 @@ unmangle() {
         fi
         ;;
     esac
-    out+=$chr
+    out+="$chr"
   done
 
   printf '%s' "$out${1:i}"
@@ -255,39 +269,37 @@ optstring_match_option() {
 
   IFS=, read -ra patterns <<<"$1"
   for pat in "${patterns[@]}"; do
-    if [[ $pat = *=* ]]; then
+    if [[ $pat = *'='* ]]; then
       # "key=val" will only ever match "key=val"
-      candidate=$2
+      candidate="$2"
     else
       # "key" will match "key", but also "key=anyval"
-      candidate=${2%%=*}
+      candidate="${2%%=*}"
     fi
 
-    [[ $pat = "$candidate" ]] && return 0
+    [[ "$pat" = "$candidate" ]] && return 0
   done
 
   return 1
 }
 
 optstring_remove_option() {
-  local o options_ remove=$2 IFS=,
+  local o _options remove="$2"
 
-  read -ra options_ <<<"${!1}"
+  IFS=, read -ra _options <<<"${!1}"
-
+  for o in "${!_options[@]}"; do
-  for o in "${!options_[@]}"; do
+    optstring_match_option "$remove" "${_options[o]}" && unset '_options[o]'
-    optstring_match_option "$remove" "${options_[o]}" && unset 'options_[o]'
   done
 
-  declare -g "$1=${options_[*]}"
+  declare -g "$1=${_options[*]}"
 }
 
 optstring_normalize() {
-  local o options_ norm IFS=,
+  local o _options norm
-
-  read -ra options_ <<<"${!1}"
 
+  IFS=, read -ra _options <<<"${!1}"
   # remove empty fields
-  for o in "${options_[@]}"; do
+  for o in "${_options[@]}"; do
     [[ $o ]] && norm+=("$o")
   done
 
@@ -295,6 +307,12 @@ optstring_normalize() {
   declare -g "$1=${norm[*]:-defaults}"
 }
 
+optstring_has_option() {
+  local o="${2%%=*}"
+
+  optstring_get_option "$1" "$o"
+}
+
 optstring_append_option() {
   if ! optstring_has_option "$1" "$2"; then
     declare -g "$1=${!1},$2"
@@ -304,8 +322,6 @@ optstring_append_option() {
 }
 
 optstring_prepend_option() {
-  local options_=$1
-
   if ! optstring_has_option "$1" "$2"; then
     declare -g "$1=$2,${!1}"
   fi
@@ -327,14 +343,8 @@ optstring_get_option() {
   return 1
 }
 
-optstring_has_option() {
-  local "${2%%=*}"
-
-  optstring_get_option "$1" "$2"
-}
-
 dm_name_for_devnode() {
-  read dm_name <"/sys/class/block/${1#/dev/}/dm/name"
+  read -r dm_name <"/sys/class/block/${1#/dev/}/dm/name"
   if [[ $dm_name ]]; then
     printf '/dev/mapper/%s' "$dm_name"
   else
@@ -351,3 +361,5 @@ fstype_is_pseudofs() {
 fstype_has_fsck() {
   (( fsck_types["$1"] ))
 }
+
+# vim: et ts=2 sw=2 ft=sh:

completion/genfstab.bash

@@ -3,7 +3,7 @@ _genfstab() {
     local cur prev words cword
     _init_completion || return
 
-    local opts="-f -L -p -P -t -U -h"
+    local opts="-f -L -P -p -t -U -h"
 
     case ${prev} in
         -f)

genfstab.in

@@ -1,7 +1,10 @@
 #!/bin/bash
+# shellcheck disable=SC2154 # optstring_*_option may export variables in runtime
 
 shopt -s extglob
 
+# m4_include() is recognized as a function definition
+# shellcheck source=common disable=SC1073,SC1065,SC1064,SC1072
 m4_include(common)
 
 write_source() {
@@ -43,7 +46,7 @@ write_source() {
 }
 
 optstring_apply_quirks() {
-  local varname=$1 fstype=$2
+  local varname="$1" fstype="$2"
 
   # SELinux displays a 'seclabel' option in /proc/self/mountinfo. We can't know
   # if the system we're generating the fstab for has any support for SELinux (as
@@ -97,8 +100,8 @@ usage: ${0##*/} [options] root
 
     -h             Print this help message
 
-genfstab generates output suitable for addition to an fstab file based on the
+genfstab generates output suitable for addition to an fstab file based on
-devices mounted under the mountpoint specified by the given root.
+the devices mounted under the mountpoint specified by the given root.
 
 EOF
 }
@@ -110,15 +113,12 @@ fi
 
 while getopts ':f:LPpt:U' flag; do
   case $flag in
+    f)
+      prefixfilter="$OPTARG"
+      ;;
     L)
       bytag=LABEL
       ;;
-    U)
-      bytag=UUID
-      ;;
-    f)
-      prefixfilter=$OPTARG
-      ;;
     P)
       pseudofs=1
       ;;
@@ -126,42 +126,45 @@ while getopts ':f:LPpt:U' flag; do
       pseudofs=0
       ;;
     t)
-      bytag=${OPTARG^^}
+      bytag="${OPTARG^^}"
+      ;;
+    U)
+      bytag=UUID
       ;;
     :)
-      die '%s: option requires an argument -- '\''%s'\' "${0##*/}" "$OPTARG"
+      die "%s: option requires an argument -- '%s'" "${0##*/}" "$OPTARG"
       ;;
     ?)
-      die '%s: invalid option -- '\''%s'\' "${0##*/}" "$OPTARG"
+      die "%s: invalid option -- '%s'" "${0##*/}" "$OPTARG"
       ;;
   esac
 done
 shift $(( OPTIND - 1 ))
 
-(( $# )) || die "No root directory specified"
+(( $# )) || die 'No root directory specified'
-root=$(realpath -mL "$1"); shift
+root="$(realpath -mL "$1")"; shift
 
 if ! mountpoint -q "$root"; then
-  die "$root is not a mountpoint"
+  die '%s: not a mountpoint' "$root"
 fi
 
 # handle block devices
 findmnt -Recvruno SOURCE,TARGET,FSTYPE,OPTIONS,FSROOT "$root" |
     while read -r src target fstype opts fsroot; do
-  if (( !pseudofs )) && fstype_is_pseudofs "$fstype"; then
+  if (( ! pseudofs )) && fstype_is_pseudofs "$fstype"; then
     continue
   fi
 
-  [[ $target = "$prefixfilter"* ]] || continue
+  [[ "$target" = "$prefixfilter"* ]] || continue
 
   # default 5th and 6th columns
   dump=0 pass=2
 
-  src=$(unmangle "$src")
+  src="$(unmangle "$src")"
-  target=$(unmangle "$target")
+  target="$(unmangle "$target")"
-  target=${target#$root}
+  target="/${target#"$root/"}"
 
-  if (( !foundroot )) && findmnt "$src" "$root" >/dev/null; then
+  if (( ! foundroot )) && findmnt "$src" "$root" >/dev/null; then
     # this is root. we can't possibly have more than one...
     pass=1 foundroot=1
   fi
@@ -171,7 +174,7 @@ findmnt -Recvruno SOURCE,TARGET,FSTYPE,OPTIONS,FSROOT "$root" |
     pass=0
   fi
 
-  if [[ $fsroot != / && $fstype != btrfs ]]; then
+  if [[ "$fsroot" != "/" && "$fstype" != "btrfs" ]]; then
     # it's a bind mount
     src=$(findmnt -funcevo TARGET "$src")$fsroot
     src="/${src#$root/}"
@@ -183,7 +186,7 @@ findmnt -Recvruno SOURCE,TARGET,FSTYPE,OPTIONS,FSROOT "$root" |
       continue
     fi
     fstype=none
-    opts+=,bind
+    opts+=',bind'
     pass=0
   fi
 
@@ -192,20 +195,20 @@ findmnt -Recvruno SOURCE,TARGET,FSTYPE,OPTIONS,FSROOT "$root" |
     fuseblk)
       # well-behaved FUSE filesystems will report themselves as fuse.$fstype.
       # this is probably NTFS-3g, but let's just make sure.
-      if ! newtype=$(lsblk -no FSTYPE "$src") || [[ -z $newtype ]]; then
+      if ! newtype="$(lsblk -no FSTYPE "$src")" || [[ -z $newtype ]]; then
         # avoid blanking out fstype, leading to an invalid fstab
         error 'Failed to derive real filesystem type for FUSE device on %s' "$target"
       else
-        fstype=$newtype
+        fstype="$newtype"
       fi
       ;;
   esac
 
-  optstring_apply_quirks "opts" "$fstype"
+  optstring_apply_quirks opts "$fstype"
 
   # write one line
   write_source "$src"
-  printf '\t%-10s' "/$(mangle "${target#/}")" "$fstype" "$opts"
+  printf '\t%-10s' "$(mangle "$target")" "$fstype" "$opts"
   printf '\t%s %s' "$dump" "$pass"
   printf '\n\n'
 done
@@ -213,20 +216,20 @@ done
 # handle swaps devices
 {
   # ignore header
-  read
+  read -r
 
   while read -r device type _ _ prio; do
     options=defaults
     if (( prio >= 0 )); then
-      options+=,pri=$prio
+      options+=",pri=$prio"
     fi
 
     # skip files marked deleted by the kernel
-    [[ $device = *'\040(deleted)' ]] && continue
+    [[ "$device" = *'\040(deleted)' ]] && continue
 
-    if [[ $type = file ]]; then
+    if [[ "$type" = "file" ]]; then
-      printf '%-20s' "${device#${root%/}}"
+      printf '%-20s' "${device#"${root%/}"}"
-    elif [[ $device = /dev/dm-+([0-9]) ]]; then
+    elif [[ "$device" = "/dev/dm-"+([0-9]) ]]; then
       # device mapper doesn't allow characters we need to worry
       # about being mangled, and it does the escaping of dashes
       # for us in sysfs.
@@ -235,7 +238,7 @@ done
       write_source "$(unmangle "$device")"
     fi
 
-    printf '\t%-10s\t%-10s\t%-10s\t0 0\n\n' 'none' 'swap' "$options"
+    printf '\t%-10s\t%-10s\t%-10s\t0 0\n\n' none swap "$options"
   done
 } </proc/swaps
 

pacstrap.in

@@ -10,18 +10,20 @@
 
 shopt -s extglob
 
+# m4_include() is recognized as a function definition
+# shellcheck source=common disable=SC1073,SC1065,SC1064,SC1072
 m4_include(common)
 
 hostcache=0
 copykeyring=1
 initkeyring=0
 copymirrorlist=1
+copyconfig=0
+pacman_config=/etc/pacman.conf
 pacman_args=()
-pacmode=-Sy
+pacmode='-Sy'
 setup=chroot_setup
 unshare=0
-copyconf=0
-pacman_config=/etc/pacman.conf
 
 usage() {
   cat <<EOF
@@ -37,12 +39,12 @@ usage: ${0##*/} [options] root [packages...]
     -M             Avoid copying the host's mirrorlist to the target
     -N             Run in unshare mode as a regular user
     -P             Copy the host's pacman config to the target
-    -U             Use pacman -U to install packages
+    -U             Use 'pacman -U' to install packages
 
     -h             Print this help message
 
-pacstrap installs packages to the specified new root directory. If no packages
+pacstrap installs packages to the specified new root directory.
-are given, pacstrap defaults to the "base" group.
+If no packages are given, pacstrap defaults to the 'base' metapackage.
 
 EOF
 }
@@ -55,20 +57,20 @@ fi
 while getopts ':C:cDGiKMNPU' flag; do
   case $flag in
     C)
-      pacman_config=$OPTARG
+      pacman_config="$OPTARG"
-      ;;
-    D)
-      pacman_args+=(-dd)
       ;;
     c)
       hostcache=1
       ;;
-    i)
+    D)
-      interactive=1
+      pacman_args+=(-dd)
       ;;
     G)
       copykeyring=0
       ;;
+    i)
+      interactive=1
+      ;;
     K)
       initkeyring=1
       ;;
@@ -80,23 +82,23 @@ while getopts ':C:cDGiKMNPU' flag; do
       unshare=1
       ;;
     P)
-      copyconf=1
+      copyconfig=1
       ;;
     U)
-      pacmode=-U
+      pacmode='-U'
       ;;
     :)
-      die '%s: option requires an argument -- '\''%s'\' "${0##*/}" "$OPTARG"
+      die "%s: option requires an argument -- '%s'" "${0##*/}" "$OPTARG"
       ;;
     ?)
-      die '%s: invalid option -- '\''%s'\' "${0##*/}" "$OPTARG"
+      die "%s: invalid option -- '%s'" "${0##*/}" "$OPTARG"
       ;;
   esac
 done
 shift $(( OPTIND - 1 ))
 
-(( $# )) || die "No root directory specified"
+(( $# )) || die 'No root directory specified'
-newroot=$1; shift
+newroot="$1"; shift
 pacman_args+=("$pacmode" "${@:-base}" --config="$pacman_config")
 
 if (( ! hostcache )); then
@@ -131,16 +133,14 @@ pacstrap() {
   fi
 
   msg 'Installing packages to %s' "$newroot"
-  if ! $pid_unshare pacman -r "$newroot" "${pacman_args[@]}"; then
+  $pid_unshare pacman --root "$newroot" "${pacman_args[@]}" || die 'Failed to install packages to new root'
-    die 'Failed to install packages to new root'
-  fi
 
   if (( copymirrorlist )); then
     # install the host's mirrorlist onto the new root
     cp -a /etc/pacman.d/mirrorlist "$newroot/etc/pacman.d/"
   fi
 
-  if (( copyconf )); then
+  if (( copyconfig )); then
     cp -a "$pacman_config" "$newroot/etc/pacman.conf"
   fi
 }