-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;
- '
- )"
+ while ! mkdir "$lock"; do
+ block="$(cat "$lock/pid" || printf 1)"
+ if ! { ps -eo pid |grep -qwF "$block"; }; then
+ printf 'Overriding stale lock: %s\n' "$lock" >&2
+ break
+ fi
+ if [ $timeout -le 0 ]; then
+ printf 'Timeout while trying to get lock: %s\n' "$lock" >&2
+ return 1
+ fi
+ timeout=$((timeout - 1))
+ sleep 1
+ done
+ printf '%i\n' $$ >"${lock}/pid"
+ return 1