1 (* Copyright (C) 2000, 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://cs.unibo.it/helm/.
26 (*****************************************************************************)
30 (* Claudio Sacerdoti Coen <sacerdot@cs.unibo.it> *)
33 (* This module implements a trival cache system (an hash-table) for cic *)
34 (* objects. Uses the getter (getter.ml) and the parser (cicParser.ml) *)
36 (*****************************************************************************)
40 (* ************************************************************************** *
41 CicEnvironment SETTINGS (trust and clean_tmp)
42 * ************************************************************************** *)
45 let cleanup_tmp = true;;
46 let trust = ref (fun _ -> true);;
47 let set_trust f = trust := f
48 let trust_obj uri = !trust uri
49 let debug_print = if debug then fun x -> prerr_endline (Lazy.force x) else ignore
51 (* ************************************************************************** *
53 * ************************************************************************** *)
55 type type_checked_obj =
56 CheckedObj of (Cic.obj * CicUniv.universe_graph) (* cooked obj *)
57 | UncheckedObj of Cic.obj (* uncooked obj to proof-check *)
60 exception AlreadyCooked of string;;
61 exception CircularDependency of string Lazy.t;;
62 exception CouldNotFreeze of string;;
63 exception CouldNotUnfreeze of string;;
64 exception Object_not_found of UriManager.uri;;
67 (* ************************************************************************** *
68 HERE STARTS THE CACHE MODULE
69 * ************************************************************************** *)
71 (* I think this should be the right place to implement mecanisms and
75 (* Cache that uses == instead of = for testing equality *)
76 (* Invariant: an object is always in at most one of the *)
77 (* following states: unchecked, frozen and cooked. *)
80 val find_or_add_to_unchecked :
84 Cic.obj * (CicUniv.universe_graph * CicUniv.universe list) option) ->
85 Cic.obj * CicUniv.universe_graph * CicUniv.universe list
87 UriManager.uri -> bool
88 val unchecked_to_frozen :
89 UriManager.uri -> unit
90 val frozen_to_cooked :
91 uri:UriManager.uri -> unit
93 UriManager.uri -> CicUniv.universe_graph * CicUniv.universe list -> unit
96 Cic.obj * CicUniv.universe_graph * CicUniv.universe list
99 (Cic.obj * CicUniv.universe_graph * CicUniv.universe list) -> unit
100 val remove: UriManager.uri -> unit
101 val dump_to_channel : ?callback:(string -> unit) -> out_channel -> unit
102 val restore_from_channel : ?callback:(string -> unit) -> in_channel -> unit
103 val empty : unit -> unit
104 val is_in_frozen: UriManager.uri -> bool
105 val is_in_unchecked: UriManager.uri -> bool
106 val is_in_cooked: UriManager.uri -> bool
107 val list_all_cooked_uris: unit -> UriManager.uri list
111 (*************************************************************************
113 The cacheOfCookedObjects will contain only objects with a valid universe
114 graph. valid means that not None (used if there is no universe file
115 in the universe generation phase).
116 **************************************************************************)
118 (* DATA: the data structure that implements the CACHE *)
121 type t = UriManager.uri
122 let equal = UriManager.eq
123 let hash = Hashtbl.hash
127 module HT = Hashtbl.Make(HashedType);;
129 let cacheOfCookedObjects = HT.create 1009;;
131 (* DATA: The parking lists
132 * the lists elements are (uri * (obj * universe_graph option))
133 * ( u, ( o, None )) means that the object has no universes file, this
134 * should happen only in the universe generation phase.
135 * FIXME: if the universe generation is integrated in the library
136 * exportation phase, the 'option' MUST be removed.
137 * ( u, ( o, Some g)) means that the object has a universes file,
141 (* frozen is used to detect circular dependency. *)
142 let frozen_list = ref [];;
143 (* unchecked is used to store objects just fetched, nothing more. *)
144 let unchecked_list = ref [];;
147 HT.clear cacheOfCookedObjects;
148 unchecked_list := [] ;
152 (* FIX: universe stuff?? *)
153 let dump_to_channel ?(callback = ignore) oc =
154 HT.iter (fun uri _ -> callback (UriManager.string_of_uri uri))
155 cacheOfCookedObjects;
156 Marshal.to_channel oc cacheOfCookedObjects []
159 (* FIX: universes stuff?? *)
160 let restore_from_channel ?(callback = ignore) ic =
161 let restored = Marshal.from_channel ic in
162 (* FIXME: should this empty clean the frozen and unchecked?
163 * if not, the only-one-empty-end-not-3 patch is wrong
168 callback (UriManager.string_of_uri k);
170 CicUtil.rehash_obj v,
171 CicUniv.recons_graph u,
172 List.map CicUniv.recons_univ l
174 HT.add cacheOfCookedObjects
175 (UriManager.uri_of_string (UriManager.string_of_uri k))
181 let is_in_frozen uri =
182 List.mem_assoc uri !frozen_list
185 let is_in_unchecked uri =
186 List.mem_assoc uri !unchecked_list
189 let is_in_cooked uri =
190 HT.mem cacheOfCookedObjects uri
194 (*******************************************************************
196 we need, in the universe generation phase, to traverse objects
197 that are not yet committed, so we search them in the frozen list.
198 Only uncommitted objects without a universe file (see the assertion)
199 can be searched with method
200 *******************************************************************)
202 let find_or_add_to_unchecked uri ~get_object_to_add =
204 let o,g_and_l = List.assq uri !unchecked_list in
206 (* FIXME: we accept both cases, as at the end of this function
207 * maybe the None universe outside the cache module should be
210 * another thing that should be removed if univ generation phase
211 * and lib exportation are unified.
213 | None -> o,CicUniv.empty_ugraph,[]
214 | Some (g,l) -> o,g,l
217 if List.mem_assq uri !frozen_list then
218 (* CIRCULAR DEPENDENCY DETECTED, print the error and raise *)
220 prerr_endline "\nCircularDependency!\nfrozen list: \n";
223 let su = UriManager.string_of_uri u in
224 let univ = if o = None then "NO_UNIV" else "" in
225 print_endline (su^" "^univ))
227 raise (CircularDependency (lazy (UriManager.string_of_uri uri)))
230 if HT.mem cacheOfCookedObjects uri then
231 (* DOUBLE COOK DETECTED, raise the exception *)
232 raise (AlreadyCooked (UriManager.string_of_uri uri))
234 (* OK, it is not already frozen nor cooked *)
235 let obj,ugraph_and_univlist = get_object_to_add uri in
236 let ugraph_real, univlist_real =
237 match ugraph_and_univlist with
238 (* FIXME: not sure it is OK*)
239 None -> CicUniv.empty_ugraph, []
240 | Some ((g,l) as g_and_l) -> g_and_l
243 (uri,(obj,ugraph_and_univlist))::!unchecked_list ;
244 obj, ugraph_real, univlist_real
247 let unchecked_to_frozen uri =
249 let obj,ugraph_and_univlist = List.assq uri !unchecked_list in
250 unchecked_list := List.remove_assq uri !unchecked_list ;
251 frozen_list := (uri,(obj,ugraph_and_univlist))::!frozen_list
253 Not_found -> raise (CouldNotFreeze (UriManager.string_of_uri uri))
257 (************************************************************
259 only object with a valid universe graph can be committed
261 this should disappear if the universe generation phase and the
262 library exportation are unified.
263 *************************************************************)
264 let frozen_to_cooked ~uri =
266 let obj,ugraph_and_univlist = List.assq uri !frozen_list in
267 match ugraph_and_univlist with
268 | None -> assert false (* only NON dummy universes can be committed *)
270 CicUniv.assert_univs_have_uri g l;
271 frozen_list := List.remove_assq uri !frozen_list ;
272 HT.add cacheOfCookedObjects uri (obj,g,l)
274 Not_found -> raise (CouldNotUnfreeze (UriManager.string_of_uri uri))
277 let can_be_cooked uri =
279 let obj,ugraph_and_univlist = List.assq uri !frozen_list in
280 (* FIXME: another thing to remove if univ generation phase and lib
281 * exportation are unified.
283 match ugraph_and_univlist with
290 (* this function injects a real universe graph in a (uri, (obj, None))
291 * element of the frozen list.
293 * FIXME: another thing to remove if univ generation phase and lib
294 * exportation are unified.
296 let hack_univ uri (real_ugraph, real_univlist) =
298 let o,ugraph_and_univlist = List.assq uri !frozen_list in
299 match ugraph_and_univlist with
301 frozen_list := List.remove_assoc uri !frozen_list;
303 (uri,(o,Some (real_ugraph, real_univlist)))::!frozen_list;
306 "You are probably hacking an object already hacked or an"^
307 " object that has the universe file but is not"^
313 "You are hacking an object that is not in the"^
314 " frozen_list, this means you are probably generating an"^
315 " universe file for an object that already"^
316 " as an universe file"));
320 let find_cooked ~key:uri = HT.find cacheOfCookedObjects uri ;;
322 let add_cooked ~key:uri (obj,ugraph,univlist) =
323 HT.add cacheOfCookedObjects uri (obj,ugraph,univlist)
328 * an object can be romeved from the cache only if we are not typechecking
329 * something. this means check and frozen must be empty.
332 if !frozen_list <> [] then
333 failwith "CicEnvironment.remove while type checking"
336 HT.remove cacheOfCookedObjects uri;
338 List.filter (fun (uri',_) -> not (UriManager.eq uri uri')) !unchecked_list
342 let list_all_cooked_uris () =
343 HT.fold (fun u _ l -> u::l) cacheOfCookedObjects []
349 (* ************************************************************************
350 HERE ENDS THE CACHE MODULE
351 * ************************************************************************ *)
353 (* exported cache functions *)
354 let dump_to_channel = Cache.dump_to_channel;;
355 let restore_from_channel = Cache.restore_from_channel;;
356 let empty = Cache.empty;;
358 let total_parsing_time = ref 0.0
360 let get_object_to_add uri =
362 let filename = Http_getter.getxml' uri in
364 match UriManager.bodyuri_of_uri uri with
367 if Http_getter.exists' bodyuri then
368 Some (Http_getter.getxml' bodyuri)
374 let time = Unix.gettimeofday() in
375 let rc = CicParser.obj_of_xml uri filename bodyfilename in
376 total_parsing_time :=
377 !total_parsing_time +. ((Unix.gettimeofday()) -. time );
381 | CicParser.Getter_failure ("key_not_found", uri) ->
382 raise (Object_not_found (UriManager.uri_of_string uri))
385 let ugraph_and_univlist,filename_univ =
388 let univ_uri = UriManager.univgraphuri_of_uri uri in
389 Http_getter.getxml' univ_uri
391 Some (CicUniv.ugraph_and_univlist_of_xml filename_univ),
394 | Http_getter_types.Key_not_found _
395 | Http_getter_types.Unresolvable_URI _ ->
397 "WE HAVE NO UNIVERSE FILE FOR " ^ (UriManager.string_of_uri uri)));
398 (* WE SHOULD FAIL (or return None, None *)
399 Some (CicUniv.empty_ugraph, []), None
401 obj, ugraph_and_univlist
402 with Http_getter_types.Key_not_found _ -> raise (Object_not_found uri)
405 (* this is the function to fetch the object in the unchecked list and
406 * nothing more (except returning it)
408 let find_or_add_to_unchecked uri =
409 Cache.find_or_add_to_unchecked uri ~get_object_to_add
411 (* set_type_checking_info uri *)
412 (* must be called once the type-checking of uri is finished *)
413 (* The object whose uri is uri is unfreezed *)
415 (* the replacement ugraph must be the one returned by the *)
416 (* typechecker, restricted with the CicUnivUtils.clean_and_fill *)
417 let set_type_checking_info ?(replace_ugraph_and_univlist=None) uri =
419 if not (Cache.can_be_cooked uri) && replace_ugraph <> None then begin
421 "?replace_ugraph must be None if you are not committing an "^
422 "object that has a universe graph associated "^
423 "(can happen only in the fase of universes graphs generation)."));
427 match Cache.can_be_cooked uri, replace_ugraph_and_univlist with
431 "?replace_ugraph must be (Some ugraph) when committing an object that "^
432 "has no associated universe graph. If this is in make_univ phase you "^
433 "should drop this exception and let univ_make commit thi object with "^
434 "proper arguments"));
437 (match replace_ugraph_and_univlist with
439 | Some g_and_l -> Cache.hack_univ uri g_and_l);
440 Cache.frozen_to_cooked uri
443 (* fetch, unfreeze and commit an uri to the cacheOfCookedObjects and
444 * return the object,ugraph
446 let add_trusted_uri_to_cache uri =
447 let _ = find_or_add_to_unchecked uri in
448 Cache.unchecked_to_frozen uri;
449 set_type_checking_info uri;
451 Cache.find_cooked uri
452 with Not_found -> assert false
455 (* get the uri, if we trust it will be added to the cacheOfCookedObjects *)
456 let get_cooked_obj_with_univlist ?(trust=true) base_ugraph uri =
458 (* the object should be in the cacheOfCookedObjects *)
459 let o,u,l = Cache.find_cooked uri in
460 o,(CicUniv.merge_ugraphs ~base_ugraph ~increment:(u,uri)),l
462 (* this should be an error case, but if we trust the uri... *)
463 if trust && trust_obj uri then
464 (* trusting means that we will fetch cook it on the fly *)
465 let o,u,l = add_trusted_uri_to_cache uri in
466 o,(CicUniv.merge_ugraphs ~base_ugraph ~increment:(u,uri)),l
468 (* we don't trust the uri, so we fail *)
470 debug_print (lazy ("CACHE MISS: " ^ (UriManager.string_of_uri uri)));
474 let get_cooked_obj ?trust base_ugraph uri =
475 let o,g,_ = get_cooked_obj_with_univlist ?trust base_ugraph uri in
478 (* This has not the old semantic :( but is what the name suggests
480 * let is_type_checked ?(trust=true) uri =
482 * let _ = Cache.find_cooked uri in
486 * trust && trust_obj uri
489 * as the get_cooked_obj but returns a type_checked_obj
492 let is_type_checked ?(trust=true) base_ugraph uri =
494 let o,u,_ = Cache.find_cooked uri in
495 CheckedObj (o,(CicUniv.merge_ugraphs ~base_ugraph ~increment:(u,uri)))
497 (* this should return UncheckedObj *)
498 if trust && trust_obj uri then
499 (* trusting means that we will fetch cook it on the fly *)
500 let o,u,_ = add_trusted_uri_to_cache uri in
501 CheckedObj ( o, CicUniv.merge_ugraphs ~base_ugraph ~increment:(u,uri))
503 let o,u,_ = find_or_add_to_unchecked uri in
504 Cache.unchecked_to_frozen uri;
508 (* as the get cooked, but if not present the object is only fetched,
509 * not unfreezed and committed
511 let get_obj base_ugraph uri =
513 (* the object should be in the cacheOfCookedObjects *)
514 let o,u,_ = Cache.find_cooked uri in
515 o,(CicUniv.merge_ugraphs ~base_ugraph ~increment:(u,uri))
517 (* this should be an error case, but if we trust the uri... *)
518 let o,u,_ = find_or_add_to_unchecked uri in
519 o,(CicUniv.merge_ugraphs ~base_ugraph ~increment:(u,uri))
523 Cache.is_in_cooked uri || Cache.is_in_frozen uri || Cache.is_in_unchecked uri
525 let add_type_checked_obj uri (obj,ugraph,univlist) =
526 Cache.add_cooked ~key:uri (obj,ugraph,univlist)
528 let in_library uri = in_cache uri || Http_getter.exists' uri
530 let remove_obj = Cache.remove
533 Cache.list_all_cooked_uris ()
539 let o,ug = get_obj CicUniv.empty_ugraph u in
544 debug_print (lazy "Who has removed the uri in the meanwhile?");