1 (* Copyright (C) 2004-2005, HELM Team.
3 * This file is part of HELM, an Hypertextual, Electronic
4 * Library of Mathematics, developed at the Computer Science
5 * Department, University of Bologna, Italy.
7 * HELM is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version 2
10 * of the License, or (at your option) any later version.
12 * HELM is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with HELM; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place - Suite 330, Boston,
22 * For details, see the HELM World-Wide-Web page,
23 * http://helm.cs.unibo.it/
32 if debug then prerr_endline ("Helm_registry debugging: " ^ (Lazy.force s))
37 let rec aux last_element = function
40 (match last_element with
41 | Some elt when elt = hd -> aux last_element tl
42 | _ -> hd :: aux (Some hd) tl)
46 let starts_with prefix =
48 let rex = Str.regexp (Str.quote prefix) in
49 fun s -> Str.string_match rex s 0
51 let prefix_len = String.length prefix in
54 String.sub s 0 prefix_len = prefix
55 with Invalid_argument _ -> false
57 let hashtbl_keys tbl = Hashtbl.fold (fun k _ acc -> k :: acc) tbl []
58 let hashtbl_pairs tbl = Hashtbl.fold (fun k v acc -> (k,v) :: acc) tbl []
62 exception Malformed_key of string
63 exception Key_not_found of string
64 exception Cyclic_definition of string
65 exception Type_error of string (* expected type, value, msg *)
66 exception Parse_error of string * int * int * string (* file, line, col, msg *)
68 (* root XML tag: used by save_to, ignored by load_from *)
69 let root_tag = "helm_registry"
73 let backup_registry registry = Hashtbl.copy registry
74 let restore_registry backup registry =
75 Hashtbl.clear registry;
76 Hashtbl.iter (fun key value -> Hashtbl.add registry key value) backup
79 * - no sequences of '_' longer than 1 are permitted
81 let valid_step_rex_raw = "[a-zA-Z0-9]+\\(_[a-z0A-Z-9]+\\)*"
82 let valid_key_rex_raw =
83 sprintf "%s\\(\\.%s\\)*" valid_step_rex_raw valid_step_rex_raw
84 let valid_key_rex = Str.regexp ("^" ^ valid_key_rex_raw ^ "$")
85 let interpolated_key_rex = Str.regexp ("\\$(" ^ valid_key_rex_raw ^ ")")
86 let dot_rex = Str.regexp "\\."
87 let spaces_rex = Str.regexp "[ \t\n\r]+"
88 let heading_spaces_rex = Str.regexp "^[ \t\n\r]+"
89 let margin_blanks_rex =
90 Str.regexp "^\\([ \t\n\r]*\\)\\([^ \t\n\r]*\\)\\([ \t\n\r]*\\)$"
92 let strip_blanks s = Str.global_replace margin_blanks_rex "\\2" s
95 (* trailing blanks are removed per default by split *)
96 Str.split spaces_rex (Str.global_replace heading_spaces_rex "" s)
97 let merge l = String.concat " " l
99 let handle_type_error f x =
100 try f x with exn -> raise (Type_error (Printexc.to_string exn))
102 (** marshallers/unmarshallers *)
104 let int = handle_type_error int_of_string
105 let float = handle_type_error float_of_string
106 let bool = handle_type_error bool_of_string
108 let of_int = handle_type_error string_of_int
109 let of_float = handle_type_error string_of_float
110 let of_bool = handle_type_error string_of_bool
112 (* escapes for xml configuration file *)
113 let (escape, unescape) =
114 let (in_enc, out_enc) = (`Enc_utf8, `Enc_utf8) in
115 (Netencoding.Html.encode ~in_enc ~out_enc (),
116 Netencoding.Html.decode ~in_enc ~out_enc ~entity_base:`Xml ())
118 let key_is_valid key =
119 if not (Str.string_match valid_key_rex key 0) then
120 raise (Malformed_key key)
122 let set' ?(replace=false) registry ~key ~value =
123 debug_print (lazy(sprintf "Setting (replace: %b) %s = %s" replace key value));
125 let add_fun = if replace then Hashtbl.replace else Hashtbl.add in
126 add_fun registry key value
128 let unset registry = Hashtbl.remove registry
130 let env_var_of_key = Str.global_replace dot_rex "__"
132 let singleton = function
134 raise (Type_error ("empty list value found where singleton was expected"))
137 let get registry key =
138 let rec aux stack key =
140 if List.mem key stack then begin
141 let msg = (String.concat " -> " (List.rev stack)) ^ " -> " ^ key in
142 raise (Cyclic_definition msg)
145 let registry_values = List.rev (Hashtbl.find_all registry key) in
146 let env_value = (* environment value *)
148 Some (Sys.getenv (env_var_of_key key))
149 with Not_found -> None
151 let values = (* resulting value *)
152 match registry_values, env_value with
153 | _, Some env -> [env]
154 | [], None -> raise (Key_not_found key)
155 | values, None -> values
157 List.map (interpolate (key :: stack)) values
158 and interpolate stack value =
159 Str.global_substitute interpolated_key_rex
161 let matched = Str.matched_string s in
162 (* "$(var)" -> "var" *)
163 let key = String.sub matched 2 (String.length matched - 3) in
164 singleton (aux stack key))
167 List.map strip_blanks (aux [] key)
169 let has registry key = Hashtbl.mem registry key
171 let get_typed registry unmarshaller key =
172 let value = singleton (get registry key) in
175 let set_typed registry marshaller ~key ~value =
176 set' ~replace:true registry ~key ~value:(marshaller value)
178 let get_opt registry unmarshaller key =
180 Some (unmarshaller (singleton (get registry key)))
181 with Key_not_found _ -> None
183 let get_opt_default registry unmarshaller ~default key =
184 match get_opt registry unmarshaller key with
188 let set_opt registry marshaller ~key ~value =
190 | None -> unset registry key
191 | Some value -> set' ~replace:true registry ~key ~value:(marshaller value)
193 let get_list registry unmarshaller key =
195 List.map unmarshaller (get registry key)
196 with Key_not_found _ -> []
198 let get_pair registry fst_unmarshaller snd_unmarshaller key =
199 let v = singleton (get registry key) in
200 match Str.split spaces_rex v with
201 | [fst; snd] -> fst_unmarshaller fst, snd_unmarshaller snd
202 | _ -> raise (Type_error "not a pair")
204 let set_list registry marshaller ~key ~value =
205 Hashtbl.remove registry key;
207 (fun v -> set' ~replace:false registry ~key ~value:(marshaller v))
212 | Element of string * (string * string) list * xml_tree list
214 let dot_RE = Str.regexp "\\."
216 let xml_tree_of_registry registry =
217 let has_child name elements =
220 | Element (_, ["name", name'], _) when name = name' -> true
224 let rec get_child name = function
226 | (Element (_, ["name", name'], _) as child) :: tl when name = name' ->
229 let child, rest = get_child name tl in
232 let rec add_key path value tree =
233 match path, tree with
234 | [key], Element (name, attrs, children) ->
235 Element (name, attrs,
236 Element ("key", ["name", key],
237 [Cdata (strip_blanks value)]) :: children)
238 | dir :: path, Element (name, attrs, children) ->
239 if has_child dir children then
240 let child, rest = get_child dir children in
241 Element (name, attrs, add_key path value child :: rest)
243 Element (name, attrs,
244 ((add_key path value (Element ("section", ["name", dir], [])))
249 (fun k v tree -> add_key ((Str.split dot_RE k)) v tree)
251 (Element (root_tag, [], []))
253 let rec stream_of_xml_tree = function
254 | Cdata s -> Xml.xml_cdata s
255 | Element (name, attrs, children) ->
257 (List.map (fun (n, v) -> (None, n, v)) attrs)
258 (stream_of_xml_trees children)
259 and stream_of_xml_trees = function
261 | hd :: tl -> [< stream_of_xml_tree hd; stream_of_xml_trees tl >]
263 let save_to registry fname =
264 let token_stream = stream_of_xml_tree (xml_tree_of_registry registry) in
265 let oc = open_out fname in
266 Xml.pp_to_outchan token_stream oc;
269 let rec load_from_absolute ?path registry fname =
270 let _path = ref (match path with None -> [] | Some p -> p)in
271 (* <section> elements entered so far *)
272 let in_key = ref false in (* have we entered a <key> element? *)
273 let cdata = ref "" in (* collected cdata (inside <key> *)
274 let push_path name = _path := name :: !_path in
275 let pop_path () = _path := List.tl !_path in
276 let start_element tag attrs =
277 match tag, attrs with
278 | "section", ["name", name] -> push_path name
279 | "key", ["name", name] -> in_key := true; push_path name
280 | "helm_registry", _ -> ()
281 | "include", ["href", fname] ->
282 debug_print (lazy ("including file " ^ fname));
283 load_from_absolute ~path:!_path registry fname
285 raise (Parse_error (fname, ~-1, ~-1,
286 (sprintf "unexpected element <%s> or wrong attribute set" tag)))
288 let end_element tag =
290 | "section" -> pop_path ()
292 let key = String.concat "." (List.rev !_path) in
293 set' registry ~key ~value:!cdata;
297 | "include" | "helm_registry" -> ()
300 let character_data text =
301 if !in_key then cdata := !cdata ^ text
304 XmlPushParser.default_callbacks with
305 XmlPushParser.start_element = Some start_element;
306 XmlPushParser.end_element = Some end_element;
307 XmlPushParser.character_data = Some character_data;
309 let xml_parser = XmlPushParser.create_parser callbacks in
310 let backup = backup_registry registry in
311 (* if path = None then Hashtbl.clear registry; *)
313 XmlPushParser.parse xml_parser (`File fname)
315 restore_registry backup registry;
318 let load_from registry ?path fname =
319 if Filename.is_relative fname then begin
320 let no_file_found = ref true in
323 | Some path -> path (* path given as argument *)
324 | None -> [ Sys.getcwd () ] (* no path given, try with cwd *)
328 let conffile = dir ^ "/" ^ fname in
329 if Sys.file_exists conffile then begin
330 no_file_found := false;
331 load_from_absolute registry conffile
334 if !no_file_found then
336 "Helm_registry.init: no configuration file named %s in [ %s ]"
337 fname (String.concat "; " path))
339 load_from_absolute registry fname
341 let fold registry ?prefix ?(interpolate = true) f init =
343 if interpolate then singleton (get registry k) else strip_blanks v
346 | None -> Hashtbl.fold (fun k v acc -> f acc k (value_of k v)) registry init
348 let key_matches = starts_with (s ^ ".") in
349 let rec fold_filter acc = function
351 | (k,v) :: tl when key_matches k ->
352 fold_filter (f acc k (value_of k v)) tl
353 | _ :: tl -> fold_filter acc tl
355 fold_filter init (hashtbl_pairs registry)
357 let iter registry ?prefix ?interpolate f =
358 fold registry ?prefix ?interpolate (fun _ k v -> f k v) ()
359 let to_list registry ?prefix ?interpolate () =
360 fold registry ?prefix ?interpolate (fun acc k v -> (k, v) :: acc) []
362 let ls registry prefix =
363 let prefix = prefix ^ "." in
364 let prefix_len = String.length prefix in
365 let key_matches = starts_with prefix in
366 let matching_keys = (* collect matching keys' _postfixes_ *)
369 if key_matches key then
370 String.sub key prefix_len (String.length key - prefix_len) :: acc
375 let (sections, keys) =
377 (fun (sections, keys) postfix ->
378 match Str.split dot_rex postfix with
379 | [key] -> (sections, key :: keys)
380 | hd_key :: _ -> (* length > 1 => nested section found *)
381 (hd_key :: sections, keys)
383 ([], []) matching_keys
385 (list_uniq (List.sort Pervasives.compare sections), keys)
387 (** {2 API implementation}
388 * functional methods above are wrapped so that they work on a default
389 * (imperative) registry*)
391 let default_registry = Hashtbl.create magic_size
393 let get key = singleton (get default_registry key)
394 let set = set' ~replace:true default_registry
395 let has = has default_registry
396 let fold ?prefix ?interpolate f init =
397 fold default_registry ?prefix ?interpolate f init
398 let iter = iter default_registry
399 let to_list = to_list default_registry
400 let ls = ls default_registry
401 let get_typed unmarshaller = get_typed default_registry unmarshaller
402 let get_opt unmarshaller = get_opt default_registry unmarshaller
403 let get_opt_default unmarshaller = get_opt_default default_registry unmarshaller
404 let get_list unmarshaller = get_list default_registry unmarshaller
405 let get_pair unmarshaller = get_pair default_registry unmarshaller
406 let set_typed marshaller = set_typed default_registry marshaller
407 let set_opt unmarshaller = set_opt default_registry unmarshaller
408 let set_list marshaller = set_list default_registry marshaller
409 let unset = unset default_registry
410 let save_to = save_to default_registry
411 let load_from = load_from default_registry
412 let clear () = Hashtbl.clear default_registry
414 let get_string = get_typed string
415 let get_int = get_typed int
416 let get_float = get_typed float
417 let get_bool = get_typed bool
418 let set_string = set_typed of_string
419 let set_int = set_typed of_int
420 let set_float = set_typed of_float
421 let set_bool = set_typed of_bool