using esceval for shell-escaped command strings

errors have been discussed in more detail in #37 and should be fixed for
most use cases with this patch.

modules/esceval.sh

@@ -0,0 +1,66 @@
+# SPDX-License-Identifier: 0BSD
+# Copyright 2014 Alexander Kozhevnikov <mentalisttraceur@gmail.com>
+
+# On 2019-04-25, this script was compatible with Bourne and POSIX shells.
+# EXCEPT for the following exceptions:
+# Function declarations (First appeared in SVR2 Bourne shells in 1984).
+# command built-in (not supported in really old Bourne shells)
+
+if command -v esceval 1>/dev/null 2>&1
+then
+ :
+else
+ if (eval 'echo ${A%%a} ${A#a}' 1>/dev/null 2>&1)
+ then
+  eval 'esceval()
+  {
+   case $# in 0) return 0; esac
+   (
+    while :
+    do
+     escaped=\'\''
+     unescaped=$1
+     while :
+     do
+      case $unescaped in
+      *\'\''*)
+       escaped=$escaped${unescaped%%\'\''*}"'"'\''"'"
+       unescaped=${unescaped#*\'\''}
+       ;;
+      *)
+       break
+      esac
+     done
+     escaped=$escaped$unescaped\'\''
+     shift
+     case $# in 0) break; esac
+     printf "%s " "$escaped" || return $?
+    done
+    printf "%s\n" "$escaped"
+   )
+  }'
+ else
+  esceval()
+  {
+   case $# in 0) return 0; esac
+   (
+    b='\\'
+    while :
+    do
+     escaped=`
+      printf '%s\n' "$1" \
+      | sed "
+         s/'/'$b''/g
+         1 s/^/'/
+         $ s/$/'/
+        "
+     ` || return $?
+     shift
+     case $# in 0) break; esac
+     printf '%s ' "$escaped" || return $?
+    done
+    printf '%s\n' "$escaped"
+   )
+  }
+ fi
+fi

pimod.sh

@@ -6,6 +6,7 @@ pushd "$(dirname "$0")" > /dev/null
 
 . ./modules/chroot.sh
 . ./modules/error.sh
+. ./modules/esceval.sh
 . ./modules/from_remote.sh
 . ./modules/mount.sh
 . ./modules/path.sh

stages/30-chroot.sh

@@ -70,7 +70,7 @@ WORKDIR() {
 RUN() {
   echo -e "\033[0;32m### RUN ${*}\033[0m"
   PATH=${GUEST_PATH} chroot "${CHROOT_MOUNT}" \
-    /bin/sh -c "cd ${WORKDIR_PATH}; $(printf ' %q' "$@")"
+    /bin/sh -c "cd ${WORKDIR_PATH}; $(esceval "$@")"
 }
 
 # HOST executed a command on the local host and can be used to prepare files,