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 Type_error of string * string * string (* expected type, value, msg *)
35 exception Parse_error of string * int * int * string (* file, line, col, msg *)
36 exception Invalid_value of (string * string) * string (* key, value, descr *)
38 type validator_id = int
40 let get_next_validator_id =
41 let next_id = ref 0 in
47 let validators = Hashtbl.create magic_size
48 let registry = Hashtbl.create magic_size
50 let backup_registry () = Hashtbl.copy registry
51 let restore_registry backup =
52 Hashtbl.clear registry;
53 Hashtbl.iter (fun key value -> Hashtbl.replace registry key value) backup
56 * - no sequences of '_' longer than 1 are permitted
57 * - no uppercase letter are permitted
59 let valid_step_rex_raw = "[a-z0-9]+(_[a-z0-9]+)*"
60 let valid_key_rex_raw =
61 sprintf "%s(\\.%s)*" valid_step_rex_raw valid_step_rex_raw
62 let valid_key_rex = Pcre.regexp ("^" ^ valid_key_rex_raw ^ "$")
64 (* escapes for xml configuration file *)
65 let (escape, unescape) =
66 let (in_enc, out_enc) = (`Enc_utf8, `Enc_utf8) in
67 (Netencoding.Html.encode ~in_enc ~out_enc (),
68 Netencoding.Html.decode ~in_enc ~out_enc ~entity_base:`Xml ())
70 let key_is_valid key =
71 if not (Pcre.pmatch ~rex:valid_key_rex key) then
72 raise (Malformed_key key)
74 let value_is_valid ~key ~value =
76 (fun (validator, descr) ->
77 if not (validator value) then
78 raise (Invalid_value ((key, value), descr)))
79 (Hashtbl.find_all validators key)
81 let set' registry ~key ~value =
82 debug_print (sprintf "Setting %s = %s" key value);
84 value_is_valid ~key ~value;
85 Hashtbl.replace registry key value
88 let dot_RE = Pcre.regexp "\\." in
90 Pcre.replace ~rex:dot_RE ~templ:"__" (String.uppercase key)
96 Some (Hashtbl.find registry key)
97 with Not_found -> None
101 Some (Sys.getenv (env_var_of_key key))
102 with Not_found -> None
104 match (registry_value, env_value) with
105 | Some reg, Some env -> env
106 | Some reg, None -> reg
107 | None, Some env -> env
108 | None, None -> raise (Key_not_found key)
110 let set = set' registry
112 let string_list_of_string s =
113 (* trailing blanks are removed per default by Pcre.split *)
114 Pcre.split ~pat:"\\s+" (Pcre.replace ~pat:"^\\s+" s)
115 let string_of_string_list l = String.concat " " l
117 let mk_get_set type_name (from_string: string -> 'a) (to_string: 'a -> string) =
119 let value = get key in
123 raise (Type_error (type_name, value, Printexc.to_string exn))
125 let setter ~key ~value = set ~key ~value:(to_string value) in
128 let (get_string, set_string) = (get, set)
129 let (get_int, set_int) = mk_get_set "int" int_of_string string_of_int
130 let (get_float, set_float) = mk_get_set "float" float_of_string string_of_float
131 let (get_string_list, set_string_list) =
132 mk_get_set "string list" string_list_of_string string_of_string_list
135 debug_print ("Saving configuration to " ^ fname);
136 let oc = open_out fname in
137 output_string oc "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n";
138 output_string oc "<helm_registry>\n";
142 fprintf oc " <value key=\"%s\">%s</value>\n" key (escape value))
144 output_string oc "</helm_registry>";
150 let add_validator ~key ~validator ~descr =
151 let id = get_next_validator_id () in
152 Hashtbl.add validators key (validator, descr);
160 let config = default_config in
161 let entry = `Entry_document [ `Extend_dtd_fully; `Parse_xml_decl ] in
163 debug_print ("Loading configuration from " ^ fname);
165 parse_wfdocument_entity config (from_file fname) default_spec
167 let fill_registry () =
168 document#root#iter_nodes (fun n ->
170 (match n#node_type with
171 | T_element "value" ->
172 let key = n#required_string_attribute "key" in
173 let value = n#data in
177 let (fname, line, pos) = n#position in
178 raise (Parse_error (fname, line, pos,
179 "Uncaught exception: " ^ Printexc.to_string exn)))
181 let backup = backup_registry () in
182 Hashtbl.clear registry;
186 restore_registry backup;
191 let dump () = Hashtbl.iter (fun k v -> printf "%s = %s\n" k v) registry