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
108 val invalidate: unit -> unit
112 (*************************************************************************
114 The cacheOfCookedObjects will contain only objects with a valid universe
115 graph. valid means that not None (used if there is no universe file
116 in the universe generation phase).
117 **************************************************************************)
119 (* DATA: the data structure that implements the CACHE *)
122 type t = UriManager.uri
123 let equal = UriManager.eq
124 let hash = Hashtbl.hash
128 module HT = Hashtbl.Make(HashedType);;
130 let cacheOfCookedObjects = HT.create 1009;;
132 (* DATA: The parking lists
133 * the lists elements are (uri * (obj * universe_graph option))
134 * ( u, ( o, None )) means that the object has no universes file, this
135 * should happen only in the universe generation phase.
136 * FIXME: if the universe generation is integrated in the library
137 * exportation phase, the 'option' MUST be removed.
138 * ( u, ( o, Some g)) means that the object has a universes file,
142 (* frozen is used to detect circular dependency. *)
143 let frozen_list = ref [];;
144 (* unchecked is used to store objects just fetched, nothing more. *)
145 let unchecked_list = ref [];;
148 let l = HT.fold (fun k (o,g,gl) acc -> (k,(o,Some (g,gl)))::acc) cacheOfCookedObjects [] in
149 unchecked_list := l ;
151 HT.clear cacheOfCookedObjects;
155 HT.clear cacheOfCookedObjects;
156 unchecked_list := [] ;
160 (* FIX: universe stuff?? *)
161 let dump_to_channel ?(callback = ignore) oc =
162 HT.iter (fun uri _ -> callback (UriManager.string_of_uri uri))
163 cacheOfCookedObjects;
164 Marshal.to_channel oc cacheOfCookedObjects []
167 (* FIX: universes stuff?? *)
168 let restore_from_channel ?(callback = ignore) ic =
169 let restored = Marshal.from_channel ic in
170 (* FIXME: should this empty clean the frozen and unchecked?
171 * if not, the only-one-empty-end-not-3 patch is wrong
176 callback (UriManager.string_of_uri k);
178 CicUtil.rehash_obj v,
179 CicUniv.recons_graph u,
180 List.map CicUniv.recons_univ l
182 HT.add cacheOfCookedObjects
183 (UriManager.uri_of_string (UriManager.string_of_uri k))
189 let is_in_frozen uri =
190 List.mem_assoc uri !frozen_list
193 let is_in_unchecked uri =
194 List.mem_assoc uri !unchecked_list
197 let is_in_cooked uri =
198 HT.mem cacheOfCookedObjects uri
202 (*******************************************************************
204 we need, in the universe generation phase, to traverse objects
205 that are not yet committed, so we search them in the frozen list.
206 Only uncommitted objects without a universe file (see the assertion)
207 can be searched with method
208 *******************************************************************)
210 let find_or_add_to_unchecked uri ~get_object_to_add =
212 let o,g_and_l = List.assq uri !unchecked_list in
214 (* FIXME: we accept both cases, as at the end of this function
215 * maybe the None universe outside the cache module should be
218 * another thing that should be removed if univ generation phase
219 * and lib exportation are unified.
221 | None -> o,CicUniv.empty_ugraph,[]
222 | Some (g,l) -> o,g,l
225 if List.mem_assq uri !frozen_list then
226 (* CIRCULAR DEPENDENCY DETECTED, print the error and raise *)
229 prerr_endline "\nCircularDependency!\nfrozen list: \n";
232 let su = UriManager.string_of_uri u in
233 let univ = if o = None then "NO_UNIV" else "" in
234 prerr_endline (su^" "^univ))
237 raise (CircularDependency (lazy (UriManager.string_of_uri uri)))
240 if HT.mem cacheOfCookedObjects uri then
241 (* DOUBLE COOK DETECTED, raise the exception *)
242 raise (AlreadyCooked (UriManager.string_of_uri uri))
244 (* OK, it is not already frozen nor cooked *)
245 let obj,ugraph_and_univlist = get_object_to_add uri in
246 let ugraph_real, univlist_real =
247 match ugraph_and_univlist with
248 (* FIXME: not sure it is OK*)
249 None -> CicUniv.empty_ugraph, []
250 | Some ((g,l) as g_and_l) -> g_and_l
253 (uri,(obj,ugraph_and_univlist))::!unchecked_list ;
254 obj, ugraph_real, univlist_real
257 let unchecked_to_frozen uri =
259 let obj,ugraph_and_univlist = List.assq uri !unchecked_list in
260 unchecked_list := List.remove_assq uri !unchecked_list ;
261 frozen_list := (uri,(obj,ugraph_and_univlist))::!frozen_list
263 Not_found -> raise (CouldNotFreeze (UriManager.string_of_uri uri))
267 (************************************************************
269 only object with a valid universe graph can be committed
271 this should disappear if the universe generation phase and the
272 library exportation are unified.
273 *************************************************************)
274 let frozen_to_cooked ~uri =
276 let obj,ugraph_and_univlist = List.assq uri !frozen_list in
277 match ugraph_and_univlist with
278 | None -> assert false (* only NON dummy universes can be committed *)
280 CicUniv.assert_univs_have_uri g l;
281 frozen_list := List.remove_assq uri !frozen_list ;
282 HT.add cacheOfCookedObjects uri (obj,g,l)
284 Not_found -> raise (CouldNotUnfreeze (UriManager.string_of_uri uri))
287 let can_be_cooked uri =
289 let obj,ugraph_and_univlist = List.assq uri !frozen_list in
290 (* FIXME: another thing to remove if univ generation phase and lib
291 * exportation are unified.
293 match ugraph_and_univlist with
300 (* this function injects a real universe graph in a (uri, (obj, None))
301 * element of the frozen list.
303 * FIXME: another thing to remove if univ generation phase and lib
304 * exportation are unified.
306 let hack_univ uri (real_ugraph, real_univlist) =
308 let o,ugraph_and_univlist = List.assq uri !frozen_list in
309 match ugraph_and_univlist with
311 frozen_list := List.remove_assoc uri !frozen_list;
313 (uri,(o,Some (real_ugraph, real_univlist)))::!frozen_list;
316 "You are probably hacking an object already hacked or an"^
317 " object that has the universe file but is not"^
323 "You are hacking an object that is not in the"^
324 " frozen_list, this means you are probably generating an"^
325 " universe file for an object that already"^
326 " as an universe file"));
330 let find_cooked ~key:uri = HT.find cacheOfCookedObjects uri ;;
332 let add_cooked ~key:uri (obj,ugraph,univlist) =
333 HT.add cacheOfCookedObjects uri (obj,ugraph,univlist)
338 * an object can be romeved from the cache only if we are not typechecking
339 * something. this means check and frozen must be empty.
342 if !frozen_list <> [] then
343 failwith "CicEnvironment.remove while type checking"
346 HT.remove cacheOfCookedObjects uri;
348 List.filter (fun (uri',_) -> not (UriManager.eq uri uri')) !unchecked_list
352 let list_all_cooked_uris () =
353 HT.fold (fun u _ l -> u::l) cacheOfCookedObjects []
359 (* ************************************************************************
360 HERE ENDS THE CACHE MODULE
361 * ************************************************************************ *)
363 (* exported cache functions *)
364 let dump_to_channel = Cache.dump_to_channel;;
365 let restore_from_channel = Cache.restore_from_channel;;
366 let empty = Cache.empty;;
368 let total_parsing_time = ref 0.0
370 let get_object_to_add uri =
372 let filename = Http_getter.getxml' uri in
374 match UriManager.bodyuri_of_uri uri with
377 if Http_getter.exists' ~local:false bodyuri then
378 Some (Http_getter.getxml' bodyuri)
384 let time = Unix.gettimeofday() in
385 let rc = CicParser.obj_of_xml uri filename bodyfilename in
386 total_parsing_time :=
387 !total_parsing_time +. ((Unix.gettimeofday()) -. time );
391 | CicParser.Getter_failure ("key_not_found", uri) ->
392 raise (Object_not_found (UriManager.uri_of_string uri))
395 let ugraph_and_univlist,filename_univ =
398 let univ_uri = UriManager.univgraphuri_of_uri uri in
399 Http_getter.getxml' univ_uri
401 Some (CicUniv.ugraph_and_univlist_of_xml filename_univ),
404 | Http_getter_types.Key_not_found _
405 | Http_getter_types.Unresolvable_URI _ ->
407 "WE HAVE NO UNIVERSE FILE FOR " ^ (UriManager.string_of_uri uri)));
408 (* WE SHOULD FAIL (or return None, None *)
409 Some (CicUniv.empty_ugraph, []), None
411 obj, ugraph_and_univlist
412 with Http_getter_types.Key_not_found _ -> raise (Object_not_found uri)
415 (* this is the function to fetch the object in the unchecked list and
416 * nothing more (except returning it)
418 let find_or_add_to_unchecked uri =
419 Cache.find_or_add_to_unchecked uri ~get_object_to_add
421 (* set_type_checking_info uri *)
422 (* must be called once the type-checking of uri is finished *)
423 (* The object whose uri is uri is unfreezed *)
425 (* the replacement ugraph must be the one returned by the *)
426 (* typechecker, restricted with the CicUnivUtils.clean_and_fill *)
427 let set_type_checking_info ?(replace_ugraph_and_univlist=None) uri =
429 if not (Cache.can_be_cooked uri) && replace_ugraph <> None then begin
431 "?replace_ugraph must be None if you are not committing an "^
432 "object that has a universe graph associated "^
433 "(can happen only in the fase of universes graphs generation)."));
437 match Cache.can_be_cooked uri, replace_ugraph_and_univlist with
441 "?replace_ugraph must be (Some ugraph) when committing an object that "^
442 "has no associated universe graph. If this is in make_univ phase you "^
443 "should drop this exception and let univ_make commit thi object with "^
444 "proper arguments"));
447 (match replace_ugraph_and_univlist with
449 | Some g_and_l -> Cache.hack_univ uri g_and_l);
450 Cache.frozen_to_cooked uri
453 (* fetch, unfreeze and commit an uri to the cacheOfCookedObjects and
454 * return the object,ugraph
456 let add_trusted_uri_to_cache uri =
457 let _ = find_or_add_to_unchecked uri in
458 Cache.unchecked_to_frozen uri;
459 set_type_checking_info uri;
461 Cache.find_cooked uri
462 with Not_found -> assert false
465 (* get the uri, if we trust it will be added to the cacheOfCookedObjects *)
466 let get_cooked_obj_with_univlist ?(trust=true) base_ugraph uri =
468 (* the object should be in the cacheOfCookedObjects *)
469 let o,u,l = Cache.find_cooked uri in
470 o,(CicUniv.merge_ugraphs ~base_ugraph ~increment:(u,uri(*,l*))),l
472 (* this should be an error case, but if we trust the uri... *)
473 if trust && trust_obj uri then
474 (* trusting means that we will fetch cook it on the fly *)
475 let o,u,l = add_trusted_uri_to_cache uri in
476 o,(CicUniv.merge_ugraphs ~base_ugraph ~increment:(u,uri(*,l*))),l
478 (* we don't trust the uri, so we fail *)
480 debug_print (lazy ("CACHE MISS: " ^ (UriManager.string_of_uri uri)));
484 let get_cooked_obj ?trust base_ugraph uri =
485 let o,g,_ = get_cooked_obj_with_univlist ?trust base_ugraph uri in
488 (* This has not the old semantic :( but is what the name suggests
490 * let is_type_checked ?(trust=true) uri =
492 * let _ = Cache.find_cooked uri in
496 * trust && trust_obj uri
499 * as the get_cooked_obj but returns a type_checked_obj
502 let is_type_checked ?(trust=true) base_ugraph uri =
504 let o,u,l = Cache.find_cooked uri in
505 CheckedObj (o,(CicUniv.merge_ugraphs ~base_ugraph ~increment:(u,uri(*,l*))))
507 (* this should return UncheckedObj *)
508 if trust && trust_obj uri then
509 (* trusting means that we will fetch cook it on the fly *)
510 let o,u,l = add_trusted_uri_to_cache uri in
511 CheckedObj ( o, CicUniv.merge_ugraphs ~base_ugraph ~increment:(u,uri(*,l*)))
513 let o,u,_ = find_or_add_to_unchecked uri in
514 Cache.unchecked_to_frozen uri;
518 (* as the get cooked, but if not present the object is only fetched,
519 * not unfreezed and committed
521 let get_obj base_ugraph uri =
523 (* the object should be in the cacheOfCookedObjects *)
524 let o,u,l = Cache.find_cooked uri in
525 o,(CicUniv.merge_ugraphs ~base_ugraph ~increment:(u,uri(*,l*)))
527 (* this should be an error case, but if we trust the uri... *)
528 let o,u,l = find_or_add_to_unchecked uri in
529 o,(CicUniv.merge_ugraphs ~base_ugraph ~increment:(u,uri(*,l*)))
533 Cache.is_in_cooked uri || Cache.is_in_frozen uri || Cache.is_in_unchecked uri
535 let add_type_checked_obj uri (obj,ugraph,univlist) =
536 Cache.add_cooked ~key:uri (obj,ugraph,univlist)
538 let in_library uri = in_cache uri || Http_getter.exists' ~local:false uri
540 let remove_obj = Cache.remove
543 Cache.list_all_cooked_uris ()
549 let o,ug = get_obj CicUniv.empty_ugraph u in
554 debug_print (lazy "Who has removed the uri in the meanwhile?");