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 (* root XML tag: used by save_to, ignored by load_from *)
42 let root_tag = "helm_registry"
44 let get_next_validator_id =
45 let next_id = ref 0 in
51 let validators = Hashtbl.create magic_size
52 let registry = Hashtbl.create magic_size
54 let backup_registry () = Hashtbl.copy registry
55 let restore_registry backup =
56 Hashtbl.clear registry;
57 Hashtbl.iter (fun key value -> Hashtbl.replace registry key value) backup
60 * - no sequences of '_' longer than 1 are permitted
61 * - no uppercase letter are permitted
63 let valid_step_rex_raw = "[a-z0-9]+\\(_[a-z0-9]+\\)*"
64 let valid_key_rex_raw =
65 sprintf "%s\(\\.%s\)*" valid_step_rex_raw valid_step_rex_raw
66 let valid_key_rex = Str.regexp ("^" ^ valid_key_rex_raw ^ "$")
67 let interpolated_key_rex = Str.regexp ("\\$(" ^ valid_key_rex_raw ^ ")")
68 let dot_rex = Str.regexp "\\."
69 let spaces_rex = Str.regexp "[ \t\n\r]+"
70 let heading_spaces_rex = Str.regexp "^[ \t\n\r]+"
73 (* trailing blanks are removed per default by split *)
74 Str.split spaces_rex (Str.global_replace heading_spaces_rex "" s)
75 let merge l = String.concat " " l
77 (* escapes for xml configuration file *)
78 let (escape, unescape) =
79 let (in_enc, out_enc) = (`Enc_utf8, `Enc_utf8) in
80 (Netencoding.Html.encode ~in_enc ~out_enc (),
81 Netencoding.Html.decode ~in_enc ~out_enc ~entity_base:`Xml ())
83 let key_is_valid key =
84 (* if not (Pcre.pmatch ~rex:valid_key_rex key) then *)
85 if not (Str.string_match valid_key_rex key 0) then
86 raise (Malformed_key key)
88 let value_is_valid ~key ~value =
90 (fun (validator, descr) ->
91 if not (validator value) then
92 raise (Invalid_value ((key, value), descr)))
93 (Hashtbl.find_all validators key)
95 let set' registry ~key ~value =
96 debug_print (sprintf "Setting %s = %s" key value);
98 value_is_valid ~key ~value;
99 Hashtbl.replace registry key value
101 let unset = Hashtbl.remove registry
103 let env_var_of_key key =
104 (* Pcre.replace ~rex:dot_rex ~templ:"__" (String.uppercase key) *)
105 Str.global_replace dot_rex "__" (String.uppercase key)
108 let rec aux stack key =
110 if List.mem key stack then begin
111 let msg = (String.concat " -> " (List.rev stack)) ^ " -> " ^ key in
112 raise (Cyclic_definition msg)
114 let registry_value = (* internal value *)
116 Some (Hashtbl.find registry key)
117 with Not_found -> None
119 let env_value = (* environment value *)
121 Some (Sys.getenv (env_var_of_key key))
122 with Not_found -> None
124 let value = (* resulting value *)
125 match (registry_value, env_value) with
126 | Some reg, Some env -> env
127 | Some reg, None -> reg
128 | None, Some env -> env
129 | None, None -> raise (Key_not_found key)
131 interpolate (key :: stack) value
132 and interpolate stack value =
133 Str.global_substitute interpolated_key_rex
135 let matched = Str.matched_string s in
136 (* "$(var)" -> "var" *)
137 let key = String.sub matched 2 (String.length matched - 3) in
143 let set = set' registry
145 let mk_get_set type_name (from_string: string -> 'a) (to_string: 'a -> string) =
147 let value = get key in
151 raise (Type_error (type_name, value, Printexc.to_string exn))
153 let setter ~key ~value = set ~key ~value:(to_string value) in
156 let (get_string, set_string) = (get, set)
157 let (get_int, set_int) = mk_get_set "int" int_of_string string_of_int
158 let (get_float, set_float) = mk_get_set "float" float_of_string string_of_float
159 let (get_bool, set_bool) = mk_get_set "bool" bool_of_string string_of_bool
160 let (get_string_list, set_string_list) = mk_get_set "string list" split merge
162 let get_opt getter key =
165 with Key_not_found _ -> None
166 let set_opt setter ~key ~value =
169 | Some value -> setter ~key ~value
170 let get_opt_default getter default key =
171 match get_opt getter key with
175 let add_validator ~key ~validator ~descr =
176 let id = get_next_validator_id () in
177 Hashtbl.add validators key (validator, descr);
186 let dtd = new dtd PxpHelmConf.pxp_config.warner `Enc_utf8 in
187 let dot_RE = Str.regexp "\\." in
188 let create_key_node key value = (* create a <key name="foo">value</key> *)
190 create_element_node ~valcheck:false PxpHelmConf.pxp_spec dtd "key" ["name", key]
192 let data = create_data_node PxpHelmConf.pxp_spec dtd value in
193 element#append_node data;
196 let is_section name =
198 match node#node_type with
199 | T_element "section" ->
200 (try node#attribute "name" = Value name with Not_found -> false)
203 let add_key_node root sections key value =
204 let rec aux node = function
206 let key_node = create_key_node key value in
207 node#append_node key_node
211 find ~deeply:false (is_section section) node
214 create_element_node ~valcheck:false PxpHelmConf.pxp_spec dtd
215 "section" ["name", section]
217 node#append_node section_node;
226 create_element_node ~valcheck:false PxpHelmConf.pxp_spec dtd "helm_registry" []
232 match List.rev (Str.split dot_RE key) with
238 add_key_node xml_root sections key value)
240 let outchan = (* let's write xml output to fname *)
241 if Unix.system "xmllint --version &> /dev/null" = Unix.WEXITED 0 then
242 (* xmllint available, use it! *)
243 Unix.open_process_out (sprintf
244 "xmllint --format --encode utf8 -o '%s' -" fname)
246 (* xmllint not available, write pxp ugly output directly to fname *)
249 xml_root#write (`Out_channel outchan) `Enc_utf8;
252 let load_from_absolute =
253 let config = PxpHelmConf.pxp_config in
254 let entry = `Entry_document [ `Extend_dtd_fully; `Parse_xml_decl ] in
255 let fold_key key_stack key =
258 | _ -> String.concat "." key_stack ^ "." ^ key
261 debug_print ("Loading configuration from " ^ fname);
263 parse_wfdocument_entity config (from_file fname) PxpHelmConf.pxp_spec
265 let rec aux key_stack node =
266 node#iter_nodes (fun n ->
268 (match n#node_type with
269 | T_element "section" ->
270 let section = n#required_string_attribute "name" in
271 aux (key_stack @ [section]) n
273 let key = n#required_string_attribute "name" in
274 let value = n#data in
275 set ~key:(fold_key key_stack key) ~value
278 let (fname, line, pos) = n#position in
279 raise (Parse_error (fname, line, pos,
280 "Uncaught exception: " ^ Printexc.to_string exn)))
282 let backup = backup_registry () in
283 Hashtbl.clear registry;
287 restore_registry backup;
290 let load_from ?path fname =
291 if Filename.is_relative fname then begin
292 let no_file_found = ref true in
295 | Some path -> path (* path given as argument *)
296 | None -> [ Sys.getcwd () ] (* no path given, try with cwd *)
300 let conffile = dir ^ "/" ^ fname in
301 if Sys.file_exists conffile then begin
302 no_file_found := false;
303 load_from_absolute conffile
306 if !no_file_found then
308 "Helm_registry.init: no configuration file named %s in [ %s ]"
309 fname (String.concat "; " path))
311 load_from_absolute fname
315 let dump () = Hashtbl.iter (fun k v -> printf "%s = %s\n" k v) registry