unfinished storage engine

diff --git a/storage.sh b/storage.sh
new file mode 100755 (executable)
index 0000000..bf8b7b9
--- /dev/null
+++ b/storage.sh
@@ -0,0 +1,73 @@
+#!/bin/sh
+
+# Copyright 2018 Paul Hänsch
+#
+# This is a file format helper, part of CGIlite.
+# 
+# CGIlite is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+# 
+# CGIlite is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+# 
+# You should have received a copy of the GNU Affero General Public License
+# along with CGIlite.  If not, see <http://www.gnu.org/licenses/>. 
+
+# ksh and zsh workaround
+case "${0##*/}" in
+  zsh) setopt -o OCTAL_ZEROES 2>&- ;; # zsh, mostly ignored by other shells
+  ksh) set -o posix ;;                # ksh, will crash most other shells
+esac
+
+STORE(){
+  # Store fields from a HTTP GET or POST string in a file
+  # usage: STORE "${QUERY_STRING}"
+  #    or: STORE "$(head -n $HTTP_CONTENT_LENGTH)"
+  # backslashes and newline characters will be escaped in field values,
+  # the escape symbol is a backslash
+  # hexadecimal character descriptions (%00 - %FF) will be expanded
+  # the + character will be converted to [space]
+  # one line in the output corresponds to exactly one field, so you can
+  # use grep to filter which fields of a query should be stored
+  printf "$(
+  printf '%s' "$@" \
+  | sed -r ':X; $bY; N; bX; :Y;
+            s;\+; ;g; s;(\\|5[Cc]);\\\\\\\\;g; s;(\n|%0[Aa]);\\\\n;g; s;(^|&)([^=]+)=;\1\2:;g; s;&;\n;g;
+            s;^\n+;;; s;$;\\n;; s;\n+;\n;g;
+            # Hexadecimal { %00 - %FF } will be transformed to octal { \000 - \377 } for posix printf
+            s;%[0123].;&\\0;g; s;%[4567].;&\\1;g; s;%[89AB].;&\\2;g; s;%[CDEF].;&\\3;g;
+            s;%[048C][0-7]\\.;&0;g; s;%[048C][89A-F]\\.;&1;g; s;%[159D][0-7]\\.;&2;g; s;%[159D][89A-F]\\.;&3;g;
+            s;%[26AE][0-7]\\.;&4;g; s;%[26AE][89A-F]\\.;&5;g; s;%[37BF][0-7]\\.;&6;g; s;%[37BF][89A-F]\\.;&7;g;
+            s;%.[08](\\..);\10;g; s;%.[19](\\..);\11;g; s;%.[2A](\\..);\12;g; s;%.[3B](\\..);\13;g;
+            s;%.[4C](\\..);\14;g; s;%.[5D](\\..);\15;g; s;%.[6E](\\..);\16;g; s;%.[7F](\\..);\17;g;
+           ' 
+  )"
+}
+
+LOAD(){
+  # read a file written by STORE and assign all fields to variables
+  # usage: eval "$(LOAD <file)"
+  #
+  # fields will be assigned to shell variables of the same name, but with the following constraints:
+  # * small letters will be converted to capitals
+  # * all non-alphanumeric characters will be converted to underscore (_)
+  # * an underscore will be prepended
+  # as a consequence variable names are guaranteed to match the regex /_[A-Z0-9_]+/
+  #
+  # field values may contain any character, proper escaping for safe use in eval is taken care of
+  # Your shell may or may not purge certain binary characters from variable values during processing
+
+  sed -r 'h; s;^[^:]+:;;
+          s;'\'';'\''\\'\'\'';g;
+          s;^.*$;'\''&'\'';;
+          s;\\n;\n;g;
+          x; s;^([^:]+):.*$;\1;
+          y;abcdefghijklmnopqrstuvwxyz;ABCDEFGHIJKLMNOPQRSTUVWXYZ;
+          s;[^A-Z0-9_];_;g; s;^.*$;_&=;;
+          G; s;^([A-Z0-9_]+=)\n;\1;;
+         '
+}