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 (*****************************************************************************)
39 (* ************************************************************************** *
40 CicEnvironment SETTINGS (trust and clean_tmp)
41 * ************************************************************************** *)
43 let cleanup_tmp = true;;
44 let trust = ref (fun _ -> true);;
45 let set_trust f = trust := f
46 let trust_obj uri = !trust uri
47 let debug_print = fun x -> prerr_endline (Lazy.force x)
49 (* ************************************************************************** *
51 * ************************************************************************** *)
53 type type_checked_obj =
54 CheckedObj of (Cic.obj * CicUniv.universe_graph) (* cooked obj *)
55 | UncheckedObj of Cic.obj (* uncooked obj to proof-check *)
58 exception AlreadyCooked of string;;
59 exception CircularDependency of string Lazy.t;;
60 exception CouldNotFreeze of string;;
61 exception CouldNotUnfreeze of string;;
62 exception Object_not_found of UriManager.uri;;
65 (* ************************************************************************** *
66 HERE STARTS THE CACHE MODULE
67 * ************************************************************************** *)
69 (* I think this should be the right place to implement mecanisms and
73 (* Cache that uses == instead of = for testing equality *)
74 (* Invariant: an object is always in at most one of the *)
75 (* following states: unchecked, frozen and cooked. *)
78 val find_or_add_to_unchecked :
82 Cic.obj * (CicUniv.universe_graph * CicUniv.universe list) option) ->
83 Cic.obj * CicUniv.universe_graph * CicUniv.universe list
85 UriManager.uri -> bool
86 val unchecked_to_frozen :
87 UriManager.uri -> unit
88 val frozen_to_cooked :
89 uri:UriManager.uri -> unit
91 UriManager.uri -> CicUniv.universe_graph * CicUniv.universe list -> unit
94 Cic.obj * CicUniv.universe_graph * CicUniv.universe list
97 (Cic.obj * CicUniv.universe_graph * CicUniv.universe list) -> unit
98 val remove: UriManager.uri -> unit
99 val dump_to_channel : ?callback:(string -> unit) -> out_channel -> unit
100 val restore_from_channel : ?callback:(string -> unit) -> in_channel -> unit
101 val empty : unit -> unit
102 val is_in_frozen: UriManager.uri -> bool
103 val is_in_unchecked: UriManager.uri -> bool
104 val is_in_cooked: UriManager.uri -> bool
105 val list_all_cooked_uris: unit -> UriManager.uri list
109 (*************************************************************************
111 The cacheOfCookedObjects will contain only objects with a valid universe
112 graph. valid means that not None (used if there is no universe file
113 in the universe generation phase).
114 **************************************************************************)
116 (* DATA: the data structure that implements the CACHE *)
119 type t = UriManager.uri
120 let equal = UriManager.eq
121 let hash = Hashtbl.hash
125 module HT = Hashtbl.Make(HashedType);;
127 let cacheOfCookedObjects = HT.create 1009;;
129 (* DATA: The parking lists
130 * the lists elements are (uri * (obj * universe_graph option))
131 * ( u, ( o, None )) means that the object has no universes file, this
132 * should happen only in the universe generation phase.
133 * FIXME: if the universe generation is integrated in the library
134 * exportation phase, the 'option' MUST be removed.
135 * ( u, ( o, Some g)) means that the object has a universes file,
139 (* frozen is used to detect circular dependency. *)
140 let frozen_list = ref [];;
141 (* unchecked is used to store objects just fetched, nothing more. *)
142 let unchecked_list = ref [];;
145 HT.clear cacheOfCookedObjects;
146 unchecked_list := [] ;
150 (* FIX: universe stuff?? *)
151 let dump_to_channel ?(callback = ignore) oc =
152 HT.iter (fun uri _ -> callback (UriManager.string_of_uri uri))
153 cacheOfCookedObjects;
154 Marshal.to_channel oc cacheOfCookedObjects []
157 (* FIX: universes stuff?? *)
158 let restore_from_channel ?(callback = ignore) ic =
159 let restored = Marshal.from_channel ic in
160 (* FIXME: should this empty clean the frozen and unchecked?
161 * if not, the only-one-empty-end-not-3 patch is wrong
166 callback (UriManager.string_of_uri k);
168 CicUtil.rehash_obj v,
169 CicUniv.recons_graph u,
170 List.map CicUniv.recons_univ l
172 HT.add cacheOfCookedObjects
173 (UriManager.uri_of_string (UriManager.string_of_uri k))
179 let is_in_frozen uri =
180 List.mem_assoc uri !frozen_list
183 let is_in_unchecked uri =
184 List.mem_assoc uri !unchecked_list
187 let is_in_cooked uri =
188 HT.mem cacheOfCookedObjects uri
192 (*******************************************************************
194 we need, in the universe generation phase, to traverse objects
195 that are not yet committed, so we search them in the frozen list.
196 Only uncommitted objects without a universe file (see the assertion)
197 can be searched with method
198 *******************************************************************)
200 let find_or_add_to_unchecked uri ~get_object_to_add =
202 let o,g_and_l = List.assq uri !unchecked_list in
204 (* FIXME: we accept both cases, as at the end of this function
205 * maybe the None universe outside the cache module should be
208 * another thing that should be removed if univ generation phase
209 * and lib exportation are unified.
211 | None -> o,CicUniv.empty_ugraph,[]
212 | Some (g,l) -> o,g,l
215 if List.mem_assq uri !frozen_list then
216 (* CIRCULAR DEPENDENCY DETECTED, print the error and raise *)
218 print_endline "\nCircularDependency!\nfrozen list: \n";
221 let su = UriManager.string_of_uri u in
222 let univ = if o = None then "NO_UNIV" else "" in
223 print_endline (su^" "^univ))
225 raise (CircularDependency (lazy (UriManager.string_of_uri uri)))
228 if HT.mem cacheOfCookedObjects uri then
229 (* DOUBLE COOK DETECTED, raise the exception *)
230 raise (AlreadyCooked (UriManager.string_of_uri uri))
232 (* OK, it is not already frozen nor cooked *)
233 let obj,ugraph_and_univlist = get_object_to_add uri in
234 let ugraph_real, univlist_real =
235 match ugraph_and_univlist with
236 (* FIXME: not sure it is OK*)
237 None -> CicUniv.empty_ugraph, []
238 | Some ((g,l) as g_and_l) -> g_and_l
241 (uri,(obj,ugraph_and_univlist))::!unchecked_list ;
242 obj, ugraph_real, univlist_real
245 let unchecked_to_frozen uri =
247 let obj,ugraph_and_univlist = List.assq uri !unchecked_list in
248 unchecked_list := List.remove_assq uri !unchecked_list ;
249 frozen_list := (uri,(obj,ugraph_and_univlist))::!frozen_list
251 Not_found -> raise (CouldNotFreeze (UriManager.string_of_uri uri))
255 (************************************************************
257 only object with a valid universe graph can be committed
259 this should disappear if the universe generation phase and the
260 library exportation are unified.
261 *************************************************************)
262 let frozen_to_cooked ~uri =
264 let obj,ugraph_and_univlist = List.assq uri !frozen_list in
265 match ugraph_and_univlist with
266 | None -> assert false (* only NON dummy universes can be committed *)
268 CicUniv.assert_univs_have_uri g l;
269 frozen_list := List.remove_assq uri !frozen_list ;
270 HT.add cacheOfCookedObjects uri (obj,g,l)
272 Not_found -> raise (CouldNotUnfreeze (UriManager.string_of_uri uri))
275 let can_be_cooked uri =
277 let obj,ugraph_and_univlist = List.assq uri !frozen_list in
278 (* FIXME: another thing to remove if univ generation phase and lib
279 * exportation are unified.
281 match ugraph_and_univlist with
288 (* this function injects a real universe graph in a (uri, (obj, None))
289 * element of the frozen list.
291 * FIXME: another thing to remove if univ generation phase and lib
292 * exportation are unified.
294 let hack_univ uri (real_ugraph, real_univlist) =
296 let o,ugraph_and_univlist = List.assq uri !frozen_list in
297 match ugraph_and_univlist with
299 frozen_list := List.remove_assoc uri !frozen_list;
301 (uri,(o,Some (real_ugraph, real_univlist)))::!frozen_list;
304 "You are probably hacking an object already hacked or an"^
305 " object that has the universe file but is not"^
311 "You are hacking an object that is not in the"^
312 " frozen_list, this means you are probably generating an"^
313 " universe file for an object that already"^
314 " as an universe file"));
318 let find_cooked ~key:uri = HT.find cacheOfCookedObjects uri ;;
320 let add_cooked ~key:uri (obj,ugraph,univlist) =
321 HT.add cacheOfCookedObjects uri (obj,ugraph,univlist)
326 * an object can be romeved from the cache only if we are not typechecking
327 * something. this means check and frozen must be empty.
330 if !frozen_list <> [] then
331 failwith "CicEnvironment.remove while type checking"
334 HT.remove cacheOfCookedObjects uri;
336 List.filter (fun (uri',_) -> not (UriManager.eq uri uri')) !unchecked_list
340 let list_all_cooked_uris () =
341 HT.fold (fun u _ l -> u::l) cacheOfCookedObjects []
347 (* ************************************************************************
348 HERE ENDS THE CACHE MODULE
349 * ************************************************************************ *)
351 (* exported cache functions *)
352 let dump_to_channel = Cache.dump_to_channel;;
353 let restore_from_channel = Cache.restore_from_channel;;
354 let empty = Cache.empty;;
356 let total_parsing_time = ref 0.0
358 let get_object_to_add uri =
360 let filename = Http_getter.getxml' uri in
362 match UriManager.bodyuri_of_uri uri with
365 if Http_getter.exists' bodyuri then
366 Some (Http_getter.getxml' bodyuri)
372 let time = Unix.gettimeofday() in
373 let rc = CicParser.obj_of_xml uri filename bodyfilename in
374 total_parsing_time :=
375 !total_parsing_time +. ((Unix.gettimeofday()) -. time );
379 | CicParser.Getter_failure ("key_not_found", uri) ->
380 raise (Object_not_found (UriManager.uri_of_string uri))
383 let ugraph_and_univlist,filename_univ =
386 let univ_uri = UriManager.univgraphuri_of_uri uri in
387 Http_getter.getxml' univ_uri
389 Some (CicUniv.ugraph_and_univlist_of_xml filename_univ),
392 | Http_getter_types.Key_not_found _
393 | Http_getter_types.Unresolvable_URI _ ->
395 "WE HAVE NO UNIVERSE FILE FOR " ^ (UriManager.string_of_uri uri)));
396 (* WE SHOULD FAIL (or return None, None *)
397 Some (CicUniv.empty_ugraph, []), None
399 obj, ugraph_and_univlist
400 with Http_getter_types.Key_not_found _ -> raise (Object_not_found uri)
403 (* this is the function to fetch the object in the unchecked list and
404 * nothing more (except returning it)
406 let find_or_add_to_unchecked uri =
407 Cache.find_or_add_to_unchecked uri ~get_object_to_add
409 (* set_type_checking_info uri *)
410 (* must be called once the type-checking of uri is finished *)
411 (* The object whose uri is uri is unfreezed *)
413 (* the replacement ugraph must be the one returned by the *)
414 (* typechecker, restricted with the CicUnivUtils.clean_and_fill *)
415 let set_type_checking_info ?(replace_ugraph_and_univlist=None) uri =
417 if not (Cache.can_be_cooked uri) && replace_ugraph <> None then begin
419 "?replace_ugraph must be None if you are not committing an "^
420 "object that has a universe graph associated "^
421 "(can happen only in the fase of universes graphs generation)."));
425 match Cache.can_be_cooked uri, replace_ugraph_and_univlist with
429 "?replace_ugraph must be (Some ugraph) when committing an object that "^
430 "has no associated universe graph. If this is in make_univ phase you "^
431 "should drop this exception and let univ_make commit thi object with "^
432 "proper arguments"));
435 (match replace_ugraph_and_univlist with
437 | Some g_and_l -> Cache.hack_univ uri g_and_l);
438 Cache.frozen_to_cooked uri
441 (* fetch, unfreeze and commit an uri to the cacheOfCookedObjects and
442 * return the object,ugraph
444 let add_trusted_uri_to_cache uri =
445 let _ = find_or_add_to_unchecked uri in
446 Cache.unchecked_to_frozen uri;
447 set_type_checking_info uri;
449 Cache.find_cooked uri
450 with Not_found -> assert false
453 (* get the uri, if we trust it will be added to the cacheOfCookedObjects *)
454 let get_cooked_obj_with_univlist ?(trust=true) base_univ uri =
456 (* the object should be in the cacheOfCookedObjects *)
457 let o,u,l = Cache.find_cooked uri in
458 o,(CicUniv.merge_ugraphs base_univ u),l
460 (* this should be an error case, but if we trust the uri... *)
461 if trust && trust_obj uri then
462 (* trusting means that we will fetch cook it on the fly *)
463 let o,u,l = add_trusted_uri_to_cache uri in
464 o,(CicUniv.merge_ugraphs base_univ u),l
466 (* we don't trust the uri, so we fail *)
468 debug_print (lazy ("CACHE MISS: " ^ (UriManager.string_of_uri uri)));
472 let get_cooked_obj ?trust base_univ uri =
473 let o,g,_ = get_cooked_obj_with_univlist ?trust base_univ uri in
476 (* This has not the old semantic :( but is what the name suggests
478 * let is_type_checked ?(trust=true) uri =
480 * let _ = Cache.find_cooked uri in
484 * trust && trust_obj uri
487 * as the get_cooked_obj but returns a type_checked_obj
490 let is_type_checked ?(trust=true) base_univ uri =
492 let o,u,_ = Cache.find_cooked uri in
493 CheckedObj (o,(CicUniv.merge_ugraphs base_univ u))
495 (* this should return UncheckedObj *)
496 if trust && trust_obj uri then
497 (* trusting means that we will fetch cook it on the fly *)
498 let o,u,_ = add_trusted_uri_to_cache uri in
499 CheckedObj ( o, CicUniv.merge_ugraphs u base_univ )
501 let o,u,_ = find_or_add_to_unchecked uri in
502 Cache.unchecked_to_frozen uri;
506 (* as the get cooked, but if not present the object is only fetched,
507 * not unfreezed and committed
509 let get_obj base_univ uri =
511 (* the object should be in the cacheOfCookedObjects *)
512 let o,u,_ = Cache.find_cooked uri in
513 o,(CicUniv.merge_ugraphs base_univ u)
515 (* this should be an error case, but if we trust the uri... *)
516 let o,u,_ = find_or_add_to_unchecked uri in
517 o,(CicUniv.merge_ugraphs base_univ u)
521 Cache.is_in_cooked uri || Cache.is_in_frozen uri || Cache.is_in_unchecked uri
523 let add_type_checked_obj uri (obj,ugraph,univlist) =
524 Cache.add_cooked ~key:uri (obj,ugraph,univlist)
526 let in_library uri = in_cache uri || Http_getter.exists' uri
528 let remove_obj = Cache.remove
531 Cache.list_all_cooked_uris ()
537 let o,ug = get_obj CicUniv.empty_ugraph u in
542 debug_print (lazy "Who has removed the uri in the meanwhile?");