1 (* Copyright (C) 2004, 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/
30 if debug then prerr_endline ("Helm_registry debugging: " ^ s)
32 exception Malformed_key of string
33 exception Key_not_found of string
34 exception Cyclic_definition of string
35 exception Type_error of string * string * string (* expected type, value, msg *)
36 exception Parse_error of string * int * int * string (* file, line, col, msg *)
37 exception Invalid_value of (string * string) * string (* key, value, descr *)
39 type validator_id = int
41 let get_next_validator_id =
42 let next_id = ref 0 in
48 let validators = Hashtbl.create magic_size
49 let registry = Hashtbl.create magic_size
51 let backup_registry () = Hashtbl.copy registry
52 let restore_registry backup =
53 Hashtbl.clear registry;
54 Hashtbl.iter (fun key value -> Hashtbl.replace registry key value) backup
57 * - no sequences of '_' longer than 1 are permitted
58 * - no uppercase letter are permitted
61 let valid_step_rex_raw = "[a-z0-9]+(_[a-z0-9]+)*"
62 let valid_key_rex_raw =
63 sprintf "^%s(\\.%s)*$" valid_step_rex_raw valid_step_rex_raw
64 let valid_key_rex = Pcre.regexp valid_key_rex_raw
65 let dot_rex = Pcre.regexp "\\."
66 let spaces_rex = Pcre.regexp "\\s+"
67 let heading_spaces_rex = Pcre.regexp "^\\s+"
69 let valid_step_rex_raw = "[a-z0-9]+\\(_[a-z0-9]+\\)*"
70 let valid_key_rex_raw =
71 sprintf "%s\(\\.%s\)*" valid_step_rex_raw valid_step_rex_raw
72 let valid_key_rex = Str.regexp ("^" ^ valid_key_rex_raw ^ "$")
73 let interpolated_key_rex = Str.regexp ("\\$(" ^ valid_key_rex_raw ^ ")")
74 let dot_rex = Str.regexp "\\."
75 let spaces_rex = Str.regexp "[ \t\n\r]+"
76 let heading_spaces_rex = Str.regexp "^[ \t\n\r]+"
78 (* escapes for xml configuration file *)
79 let (escape, unescape) =
80 let (in_enc, out_enc) = (`Enc_utf8, `Enc_utf8) in
81 (Netencoding.Html.encode ~in_enc ~out_enc (),
82 Netencoding.Html.decode ~in_enc ~out_enc ~entity_base:`Xml ())
84 let key_is_valid key =
85 (* if not (Pcre.pmatch ~rex:valid_key_rex key) then *)
86 if not (Str.string_match valid_key_rex key 0) then
87 raise (Malformed_key key)
89 let value_is_valid ~key ~value =
91 (fun (validator, descr) ->
92 if not (validator value) then
93 raise (Invalid_value ((key, value), descr)))
94 (Hashtbl.find_all validators key)
96 let set' registry ~key ~value =
97 debug_print (sprintf "Setting %s = %s" key value);
99 value_is_valid ~key ~value;
100 Hashtbl.replace registry key value
102 let env_var_of_key key =
103 (* Pcre.replace ~rex:dot_rex ~templ:"__" (String.uppercase key) *)
104 Str.global_replace dot_rex "__" (String.uppercase key)
107 let rec aux stack key =
109 if List.mem key stack then begin
110 let msg = (String.concat " -> " (List.rev stack)) ^ " -> " ^ key in
111 raise (Cyclic_definition msg)
113 let registry_value = (* internal value *)
115 Some (Hashtbl.find registry key)
116 with Not_found -> None
118 let env_value = (* environment value *)
120 Some (Sys.getenv (env_var_of_key key))
121 with Not_found -> None
123 let value = (* resulting value *)
124 match (registry_value, env_value) with
125 | Some reg, Some env -> env
126 | Some reg, None -> reg
127 | None, Some env -> env
128 | None, None -> raise (Key_not_found key)
130 interpolate (key :: stack) value
131 and interpolate stack value =
132 Str.global_substitute interpolated_key_rex
134 let matched = Str.matched_string s in
135 (* "$(var)" -> "var" *)
136 let key = String.sub matched 2 (String.length matched - 3) in
142 let set = set' registry
144 let string_list_of_string s =
145 (* trailing blanks are removed per default by split *)
146 (* Pcre.split ~res:spaces_rex (Pcre.replace ~rex:heading_spaces_rex s) *)
147 Str.split spaces_rex (Str.global_replace heading_spaces_rex "" s)
148 let string_of_string_list l = String.concat " " l
150 let mk_get_set type_name (from_string: string -> 'a) (to_string: 'a -> string) =
152 let value = get key in
156 raise (Type_error (type_name, value, Printexc.to_string exn))
158 let setter ~key ~value = set ~key ~value:(to_string value) in
161 let (get_string, set_string) = (get, set)
162 let (get_int, set_int) = mk_get_set "int" int_of_string string_of_int
163 let (get_float, set_float) = mk_get_set "float" float_of_string string_of_float
164 let (get_string_list, set_string_list) =
165 mk_get_set "string list" string_list_of_string string_of_string_list
168 debug_print ("Saving configuration to " ^ fname);
169 let oc = open_out fname in
170 output_string oc "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n";
171 output_string oc "<helm_registry>\n";
175 fprintf oc " <value key=\"%s\">%s</value>\n" key (escape value))
177 output_string oc "</helm_registry>";
183 let add_validator ~key ~validator ~descr =
184 let id = get_next_validator_id () in
185 Hashtbl.add validators key (validator, descr);
193 let config = default_config in
194 let entry = `Entry_document [ `Extend_dtd_fully; `Parse_xml_decl ] in
196 debug_print ("Loading configuration from " ^ fname);
198 parse_wfdocument_entity config (from_file fname) default_spec
200 let fill_registry () =
201 document#root#iter_nodes (fun n ->
203 (match n#node_type with
204 | T_element "value" ->
205 let key = n#required_string_attribute "key" in
206 let value = n#data in
210 let (fname, line, pos) = n#position in
211 raise (Parse_error (fname, line, pos,
212 "Uncaught exception: " ^ Printexc.to_string exn)))
214 let backup = backup_registry () in
215 Hashtbl.clear registry;
219 restore_registry backup;
224 let dump () = Hashtbl.iter (fun k v -> printf "%s = %s\n" k v) registry