hack: add shellcheck

Signed-off-by: Tonis Tiigi <tonistiigi@gmail.com>

.github/workflows/validate.yml

@@ -21,3 +21,4 @@ jobs:
         name: Run
         run: |
           ./hack/validate-shfmt
+          ./hack/shellcheck

base/xx-apk

@@ -4,8 +4,8 @@ set -e
 
 if [ -z "$XX_APK_NOLOCK" ]; then
   lock="/var/lock/xx-apk"
-  exec 200>$lock
-  flock -x 200
+  exec 9>$lock
+  flock -x 9
   export XX_APK_NOLOCK=1
 fi
 
@@ -14,7 +14,7 @@ if [ -n "$XX_DEBUG_APK" ]; then
 fi
 
 for l in $(xx-info env); do
-  export $l
+  export "${l?}"
 done
 
 if [ "${TARGETOS}" != "linux" ]; then
@@ -44,15 +44,15 @@ setup() {
   cp /etc/apk/repositories "$apk_dir/"
   mkdir "$apk_dir/keys"
   mkdir "$apk_dir/protected_paths.d"
-  echo $XX_PKG_ARCH >"$apk_dir/arch"
+  echo "$XX_PKG_ARCH" >"$apk_dir/arch"
   apk add --no-cache --initdb -p "/${XX_TRIPLE}" --allow-untrusted alpine-keys
 
   if [ -d "/etc/apk/cache" ]; then
-    mkdir -p /etc/apk/cache/_$XX_PKG_ARCH
-    ln -s /etc/apk/cache/_$XX_PKG_ARCH "$apk_dir/cache"
+    mkdir -p "/etc/apk/cache/_$XX_PKG_ARCH"
+    ln -s "/etc/apk/cache/_$XX_PKG_ARCH" "$apk_dir/cache"
   fi
 
-  touch $done_file
+  touch "$done_file"
 }
 
 clean() {
@@ -64,25 +64,38 @@ clean() {
     echo >&2 "invalid triple root $XX_TRIPLE"
     exit 1
   fi
-  rm -rf "/${XX_TRIPLE}"
+  rm -rf "/${XX_TRIPLE:?}"
 }
 
 cmd() {
   setup
-  root="-p /"
+  root="/"
   if xx-info is-cross; then
-    root="-p /${XX_TRIPLE}"
+    root="/${XX_TRIPLE}"
   fi
-  args=$(echo "$@" | sed "s/xx-c-essentials/musl-dev gcc/" | sed "s/xx-cxx-essentials/g++/")
-  if [ "$#" = "0" ]; then
-    root=""
-  else
-    echo "+ apk $root" "$args"
+  n=$#
+  for a in "$@"; do
+    if [ $# = $n ]; then set --; fi
+    case "$a" in
+      "xx-c-essentials")
+        set -- "$@" musl-dev gcc
+      ;;
+      "xx-cxx-essentials")
+        set -- "$@" g++
+      ;;
+      *)
+        set -- "$@" "$a"
+      ;;
+    esac
+  done
+  if [ "$#" != "0" ]; then
+    set -- "--root" "$root" "$@"
+    echo "+ apk " "$@"
   fi
-  apk $root $args
+  apk "$@"
   if xx-info is-cross; then
     if [ -z "$XX_APK_KEEP_BINARIES" ]; then
-      rm -rf /${XX_TRIPLE}/usr/bin/*
+      rm -rf "/${XX_TRIPLE:?}/usr/bin/*"
     fi
   fi
 }

base/xx-apt

@@ -14,7 +14,7 @@ if [ -n "$XX_DEBUG_APT" ]; then
 fi
 
 for l in $(xx-info env); do
-  export $l
+  export "${l?}"
 done
 
 if [ "${TARGETOS}" != "linux" ]; then
@@ -34,9 +34,9 @@ esac
 
 packages=
 parsed=
-args=
-
+n=$#
 for p in "$@"; do
+  if [ $# = $n ]; then set --; fi
   arg=
   case "$p" in
     -*)
@@ -59,11 +59,7 @@ for p in "$@"; do
       ;;
   esac
   if [ -n "$arg" ]; then
-    if [ -z "$args" ]; then
-      args="$arg"
-    else
-      args="${args} ${arg}"
-    fi
+    set -- "$@" "$arg"
   fi
 done
 
@@ -90,13 +86,13 @@ packages2=
 for p in ${packages}; do
   if [ "${p}" = "xx-c-essentials" ]; then
     p="libc6-dev"
-    if apt info libgcc-10-dev:${XX_PKG_ARCH}; then
+    if apt info "libgcc-10-dev:${XX_PKG_ARCH}"; then
       p="$p libgcc-10-dev"
     else
       p="$p libgcc-8-dev"
     fi
   elif [ "${p}" = "xx-cxx-essentials" ]; then
-    if apt info libstdc++-10-dev:${XX_PKG_ARCH}; then
+    if apt info "libstdc++-10-dev:${XX_PKG_ARCH}"; then
       p="libstdc++-10-dev"
     else
       p="libstdc++-8-dev"
@@ -109,24 +105,19 @@ for p in ${packages}; do
   fi
 done
 
-new=
 for p in ${packages2}; do
   n=
   if [ -n "$nocross" ]; then
     n=${p}
-  elif apt info ${p}-${suffix} >/dev/null 2>/dev/null; then
+  elif apt info "${p}-${suffix}" >/dev/null 2>/dev/null; then
     n="${p}-${suffix}"
-  elif [ -n "${XX_APT_PREFER_CROSS}" ] && apt info ${p}-${XX_PKG_ARCH}-cross >/dev/null 2>/dev/null; then
+  elif [ -n "${XX_APT_PREFER_CROSS}" ] && apt info "${p}-${XX_PKG_ARCH}-cross" >/dev/null 2>/dev/null; then
     n="${p}-${XX_PKG_ARCH}-cross"
   else
     n="${p}:${XX_PKG_ARCH}"
   fi
-  if [ -z "$new" ]; then
-    new="$n"
-  else
-    new="${new} ${n}"
-  fi
+  set -- "$@" "$n"
 done
 
-echo >&2 "+ apt ${args} ${new}"
-exec apt ${args} ${new}
+echo >&2 "+ apt " "$@"
+exec apt "$@"