--- /dev/null
+(******************************************************************************)
+(* SXSI : XPath evaluator *)
+(* Kim Nguyen (Kim.Nguyen@nicta.com.au) *)
+(* Copyright NICTA 2008 *)
+(* Distributed under the terms of the LGPL (see LICENCE) *)
+(******************************************************************************)
+INCLUDE "debug.ml"
+INCLUDE "utils.ml"
+
+
+external init_lib : unit -> unit = "caml_init_lib"
+
+exception CPlusPlusError of string
+
+let () = Callback.register_exception "CPlusPlusError" (CPlusPlusError "")
+
+let () = init_lib ()
+
+type node = [ `Tree ] Node.t
+
+type tree
+
+type bit_vector = string
+
+external bool_of_int : int -> bool = "%identity"
+
+let bit_vector_unsafe_get v i =
+ bool_of_int
+ (((Char.code (String.unsafe_get v (i lsr 3))) lsr (i land 7)) land 1)
+
+type t = {
+ doc : tree;
+ elements: Ptset.Int.t;
+ attributes: Ptset.Int.t;
+ attribute_array : Tag.t array;
+ children : Ptset.Int.t array;
+ siblings : Ptset.Int.t array;
+ descendants: Ptset.Int.t array;
+ followings: Ptset.Int.t array;
+}
+
+
+
+external parse_xml_uri : string -> int -> bool -> bool -> int -> tree = "caml_call_shredder_uri"
+external parse_xml_string : string -> int -> bool -> bool -> int -> tree = "caml_call_shredder_string"
+external tree_print_xml_fast3 : tree -> [`Tree ] Node.t -> Unix.file_descr -> unit = "caml_xml_tree_print"
+let print_xml t n fd =
+ tree_print_xml_fast3 t.doc n fd
+
+
+external tree_save : tree -> Unix.file_descr -> string -> unit = "caml_xml_tree_save"
+external tree_load : Unix.file_descr -> string -> bool -> int -> tree = "caml_xml_tree_load"
+
+external nullt : unit -> 'a Node.t = "caml_xml_tree_nullt"
+
+let nil : [`Tree ] Node.t = Node.nil
+let root : [`Tree ] Node.t = Node.null
+
+type unordered_set
+
+external unordered_set_alloc : int -> unordered_set = "caml_unordered_set_alloc"
+external unordered_set_length : unordered_set -> int = "caml_unordered_set_length"
+external unordered_set_insert : unordered_set -> int -> unit = "caml_unordered_set_set" "noalloc"
+
+module HPtset = Hashtbl.Make(Ptset.Int)
+
+let vector_htbl = HPtset.create MED_H_SIZE
+
+let unordered_set_of_set s =
+ try
+ HPtset.find vector_htbl s
+ with
+ Not_found ->
+ let v = unordered_set_alloc (Ptset.Int.cardinal s) in
+ let _ = Ptset.Int.iter (fun e -> unordered_set_insert v e) s in
+ HPtset.add vector_htbl s v; v
+
+let ptset_to_vector = unordered_set_of_set
+
+(** tree interface *)
+
+external tree_root : tree -> [`Tree] Node.t = "caml_xml_tree_root" "noalloc"
+
+
+external tree_first_child : tree -> [`Tree] Node.t -> [`Tree] Node.t = "caml_xml_tree_first_child" "noalloc"
+let first_child t n = tree_first_child t.doc n
+
+external tree_first_element : tree -> [`Tree] Node.t -> [`Tree] Node.t = "caml_xml_tree_first_element" "noalloc"
+let first_element t n = tree_first_element t.doc n
+
+external tree_tagged_child : tree -> [`Tree] Node.t -> Tag.t -> [`Tree] Node.t = "caml_xml_tree_tagged_child" "noalloc"
+let tagged_child t n tag = tree_tagged_child t.doc n tag
+
+external tree_select_child : tree -> [`Tree ] Node.t -> unordered_set -> [`Tree] Node.t = "caml_xml_tree_select_child" "noalloc"
+let select_child t n tag_set = tree_select_child t.doc n tag_set
+
+external tree_last_child : tree -> [`Tree] Node.t -> [`Tree] Node.t = "caml_xml_tree_last_child" "noalloc"
+let last_child t n = tree_last_child t.doc n
+
+
+
+external tree_next_sibling : tree -> [`Tree] Node.t -> [`Tree] Node.t = "caml_xml_tree_next_sibling" "noalloc"
+let next_sibling t n = tree_next_sibling t.doc n
+
+external tree_next_element : tree -> [`Tree] Node.t -> [`Tree] Node.t = "caml_xml_tree_next_element" "noalloc"
+let next_element t n = tree_next_element t.doc n
+
+external tree_tagged_following_sibling : tree -> [`Tree] Node.t -> Tag.t -> [`Tree] Node.t = "caml_xml_tree_tagged_following_sibling" "noalloc"
+let tagged_following_sibling t n tag = tree_tagged_following_sibling t.doc n tag
+
+external tree_select_following_sibling : tree -> [`Tree ] Node.t -> unordered_set -> [`Tree] Node.t = "caml_xml_tree_select_following_sibling" "noalloc"
+let select_following_sibling t n tag_set = tree_select_following_sibling t.doc n tag_set
+
+external tree_prev_sibling : tree -> [`Tree] Node.t -> [`Tree] Node.t = "caml_xml_tree_prev_sibling" "noalloc"
+let prev_sibling t n = tree_prev_sibling t.doc n
+
+
+
+external tree_tagged_descendant : tree -> [`Tree ] Node.t -> Tag.t -> [`Tree ] Node.t = "caml_xml_tree_tagged_descendant" "noalloc"
+let tagged_descendant t n tag = tree_tagged_descendant t.doc n tag
+
+external tree_select_descendant : tree -> [`Tree ] Node.t -> unordered_set -> [`Tree] Node.t = "caml_xml_tree_select_descendant" "noalloc"
+let select_descendant t n tag_set = tree_select_descendant t.doc n tag_set
+
+external tree_tagged_following_before : tree -> [`Tree ] Node.t -> Tag.t -> [`Tree ] Node.t -> [`Tree ] Node.t = "caml_xml_tree_tagged_following_before" "noalloc"
+let tagged_following_before t n tag ctx = tree_tagged_following_before t.doc n tag ctx
+
+external tree_select_following_before : tree -> [`Tree ] Node.t -> unordered_set -> [`Tree] Node.t -> [`Tree] Node.t = "caml_xml_tree_select_following_before" "noalloc"
+let select_following_before t n tag_set ctx = tree_select_following_before t.doc n tag_set ctx
+
+external tree_parent : tree -> [`Tree] Node.t -> [`Tree] Node.t = "caml_xml_tree_parent" "noalloc"
+let parent t n = tree_parent t.doc n
+
+external tree_binary_parent : tree -> [`Tree] Node.t -> [`Tree] Node.t = "caml_xml_tree_binary_parent"
+ "noalloc"
+let binary_parent t n = tree_binary_parent t.doc n
+
+
+external tree_tag : tree -> [`Tree] Node.t -> Tag.t = "caml_xml_tree_tag" "noalloc"
+let tag t n = tree_tag t.doc n
+
+external tree_is_first_child : tree -> [ `Tree ] Node.t -> bool = "caml_xml_tree_is_first_child" "noalloc"
+let is_first_child t n = tree_is_first_child t.doc n
+
+external tree_is_right_descendant : tree -> [ `Tree ] Node.t -> [`Tree] Node.t -> bool =
+ "caml_xml_tree_is_right_descendant" "noalloc"
+
+let is_right_descendant t n1 n2 = tree_is_right_descendant t.doc n1 n2
+;;
+
+let node_tags t = Ptset.Int.add Tag.document_node t.descendants.(Tag.document_node)
+
+let attribute_tags t = t.attributes
+
+let element_tags t = t.elements
+
+let tags t tag =
+ t.children.(tag), t.descendants.(tag), t.siblings.(tag), t.followings.(tag)
+
+open Format
+let dump_tag_table t =
+ eprintf "Child tags:\n%!";
+ Array.iteri
+ (fun tag set -> eprintf "%s: %a\n%!"
+ (Tag.to_string tag) TagSet.print (TagSet.inj_positive set))
+ t.children;
+ eprintf "-----------------------------\n%!";
+ eprintf "Descendant tags:\n%!";
+ Array.iteri
+ (fun tag set -> eprintf "%s: %a\n%!"
+ (Tag.to_string tag) TagSet.print (TagSet.inj_positive set))
+ t.descendants;
+ eprintf "-----------------------------\n%!";
+ eprintf "Sibling tags:\n%!";
+ Array.iteri
+ (fun tag set -> eprintf "%s: %a\n%!"
+ (Tag.to_string tag) TagSet.print (TagSet.inj_positive set))
+ t.siblings;
+ eprintf "-----------------------------\n%!";
+ eprintf "Following tags:\n%!";
+ Array.iteri
+ (fun tag set -> eprintf "%s: %a\n%!"
+ (Tag.to_string tag) TagSet.print (TagSet.inj_positive set))
+ t.followings;
+ eprintf "-----------------------------\n%!"
+
+
+external tree_subtree_tags : tree -> [`Tree] Node.t -> Tag.t -> int = "caml_xml_tree_subtree_tags" "noalloc"
+let subtree_tags t n tag = tree_subtree_tags t.doc n tag
+
+external tree_subtree_size : tree -> [`Tree] Node.t -> int = "caml_xml_tree_subtree_size" "noalloc"
+let subtree_size t n = tree_subtree_size t.doc n
+
+let subtree_elements t node =
+ let size = tree_subtree_size t.doc node - 1 in
+ if size == 0 then 0
+ else let size = size - (tree_subtree_tags t.doc node Tag.pcdata) in
+ if size < 2 then size else
+ let acc = ref size in
+ for i = 0 to Array.length t.attribute_array - 1 do
+ acc := !acc - tree_subtree_tags t.doc node t.attribute_array.(i)
+ done;
+ !acc
+
+external tree_closing : tree -> [`Tree] Node.t -> [`Tree] Node.t = "caml_xml_tree_closing" "noalloc"
+let closing t n = tree_closing t.doc n
+
+external tree_num_tags : tree -> int = "caml_xml_tree_num_tags" "noalloc"
+let num_tags t = tree_num_tags t.doc
+
+external tree_size : tree -> int = "caml_xml_tree_size" "noalloc"
+let size t = tree_size t.doc
+
+
+let stats t =
+ let tree = t.doc in
+ let rec loop left node acc_d total_d num_leaves =
+ if node == nil then
+ (acc_d+total_d,if left then num_leaves+1 else num_leaves)
+ else
+ let d,td = loop true (tree_first_child tree node) (acc_d+1) total_d num_leaves in
+ loop false (tree_next_sibling tree node) (acc_d) d td
+ in
+ let a,b = loop true root 0 0 0
+ in
+ Printf.eprintf "Average depth: %f, number of leaves %i\n%!" ((float_of_int a)/. (float_of_int b)) b
+;;
+
+module TagS =
+ struct
+ include Ptset.Make (
+ struct type t = int
+ type data = t
+ external hash : t -> int = "%identity"
+ external uid : t -> Uid.t = "%identity"
+ external equal : t -> t -> bool = "%eq"
+ external make : t -> int = "%identity"
+ external node : t -> int = "%identity"
+ external stats : unit -> unit = "%identity"
+ end
+ )
+ let to_ptset s = fold (Ptset.Int.add) s Ptset.Int.empty
+ end
+
+module TSTSCache =
+ Hashtbl.Make(struct type t = TagS.t * TagS.t
+ let hash (x, y) =
+ HASHINT2(Uid.to_int x.TagS.Node.id,
+ Uid.to_int y.TagS.Node.id)
+ let equal u v =
+ let u1,u2 = u
+ and v1,v2 = v in
+ u1 == v1 && u2 == v2
+ end)
+module TagTSCache =
+ Hashtbl.Make(struct type t = Tag.t * TagS.t
+ let hash (x, y) =
+ HASHINT2(x, Uid.to_int y.TagS.Node.id)
+ let equal u v =
+ let u1,u2 = u
+ and v1,v2 = v in
+ u1 == v1 && u2 == v2
+ end)
+
+let add_cache = TagTSCache.create 1023
+let union_cache = TSTSCache.create 1023
+let subset_cache = TSTSCache.create 1023
+
+let clear_cache () =
+ TSTSCache.clear union_cache;
+ TSTSCache.clear subset_cache;
+ TagTSCache.clear add_cache
+
+let _subset x y =
+ (x == y) || (x == TagS.empty) ||
+ if y == TagS.empty then false
+ else
+ let key = (x, y) in
+ try
+ TSTSCache.find subset_cache key
+ with
+ | Not_found ->
+ let z = TagS.subset x y in
+ TSTSCache.add subset_cache key z; z
+
+let order ((x, y) as z) =
+ if x.TagS.Node.id <= y.TagS.Node.id then z
+ else (y, x)
+
+let _union x y =
+ if _subset x y then y
+ else if _subset y x then x
+ else
+ let key = order (x, y) in
+ try
+ TSTSCache.find union_cache key
+ with
+ | Not_found ->
+ let z = TagS.union x y in
+ TSTSCache.add union_cache key z; z
+
+let _add t s =
+ let key = (t,s) in
+ try
+ TagTSCache.find add_cache key
+ with
+ | Not_found ->
+ let z = TagS.add t s in
+ TagTSCache.add add_cache key z;z
+
+let child_sibling_labels tree =
+ let table_c = Array.create (tree_num_tags tree) TagS.empty in
+ let table_n = Array.copy table_c in
+ let rec loop node =
+ if node == nil then TagS.empty
+ else
+ let children = loop (tree_first_child tree node) in
+ let tag = tree_tag tree node in
+ let () =
+ let tc = table_c.(tag) in
+ if _subset children tc then ()
+ else table_c.(tag) <- _union tc children
+ in
+ let siblings = loop (tree_next_sibling tree node) in
+ let () =
+ let tn = table_n.(tag) in
+ if _subset siblings tn then ()
+ else table_n.(tag) <- _union tn siblings
+ in
+ _add tag siblings
+ in
+ ignore (loop root);
+ table_c, table_n
+
+let descendant_labels tree =
+ let table_d = Array.create (tree_num_tags tree) TagS.empty in
+ let rec loop node =
+ if node == nil then TagS.empty else
+ let d1 = loop (tree_first_child tree node) in
+ let d2 = loop (tree_next_sibling tree node) in
+ let tag = tree_tag tree node in
+ let () =
+ let td = table_d.(tag) in
+ if _subset d1 td then ()
+ else table_d.(tag) <- _union td d1;
+ in
+ _add tag (_union d1 d2)
+ in
+ ignore (loop root);
+ table_d
+
+let collect_labels tree =
+ let table_f = Array.create (tree_num_tags tree) TagS.empty in
+ let table_n = Array.copy table_f in
+ let table_c = Array.copy table_f in
+ let table_d = Array.copy table_f in
+ let rec loop node foll_siblings descendants followings =
+ if node == nil then foll_siblings, descendants, followings else
+ let tag = tree_tag tree node in
+ let () =
+ let tf = table_f.(tag) in
+ if _subset followings tf then ()
+ else table_f.(tag) <- _union tf followings in
+ let () =
+ let tn = table_n.(tag) in
+ if _subset foll_siblings tn then ()
+ else table_n.(tag) <- _union tn foll_siblings in
+ let children, n_descendants, n_followings =
+ loop (tree_last_child tree node) TagS.empty TagS.empty followings
+ in
+ let () =
+ let tc = table_c.(tag) in
+ if _subset children tc then ()
+ else table_c.(tag) <- _union tc children
+ in
+ let () =
+ let td = table_d.(tag) in
+ if _subset n_descendants td then ()
+ else table_d.(tag) <- _union td n_descendants
+ in
+ loop (tree_prev_sibling tree node)
+ (_add tag foll_siblings)
+ (_add tag (_union n_descendants descendants))
+ (_add tag n_followings)
+ in
+ ignore (loop root TagS.empty TagS.empty TagS.empty);
+ table_f, table_n, table_c, table_d
+
+
+let is_nil t = t == nil
+let is_node t = t != nil
+let is_root t = t == root
+
+let node_of_t t =
+ let _ = Tag.init (Obj.magic t) in
+ let f, n, c, d = time collect_labels t ~msg:"Building tag relationship table" in
+ let c = Array.map TagS.to_ptset c in
+ let n = Array.map TagS.to_ptset n in
+ let f = Array.map TagS.to_ptset f in
+ let d = Array.map TagS.to_ptset d in
+ let () = clear_cache () in
+ let attributes = Ptset.Int.add Tag.attribute d.(Tag.attribute) in
+ let elements = Ptset.Int.add Tag.document_node
+ (Ptset.Int.remove Tag.pcdata
+ (Ptset.Int.diff d.(Tag.document_node) attributes))
+ in
+ { doc= t;
+ attributes = attributes;
+ attribute_array = Array.of_list (Ptset.Int.elements attributes);
+ elements = elements;
+ children = c;
+ siblings = n;
+ descendants = d;
+ followings = f
+
+ }
+
+let parse f str =
+ node_of_t
+ (f str !Options.sample_factor
+ !Options.index_empty_texts
+ !Options.disable_text_collection
+ !Options.text_index_type
+ )
+
+let parse_xml_uri str = parse parse_xml_uri str
+let parse_xml_string str = parse parse_xml_string str
+
+let size t = tree_size t.doc;;
+
+external pool : tree -> Tag.pool = "%identity"
+
+let magic_string = "SXSI_INDEX"
+let version_string = "3"
+
+let pos fd =
+ Unix.lseek fd 0 Unix.SEEK_CUR
+
+let pr_pos fd = Printf.eprintf "At position %i\n%!" (pos fd)
+
+let write fd s =
+ let sl = String.length s in
+ let ssl = Printf.sprintf "%020i" sl in
+ ignore (Unix.write fd ssl 0 20);
+ ignore (Unix.write fd s 0 (String.length s))
+
+let rec really_read fd buffer start length =
+ if length <= 0 then () else
+ match Unix.read fd buffer start length with
+ 0 -> raise End_of_file
+ | r -> really_read fd buffer (start + r) (length - r);;
+
+let read fd =
+ let buffer = String.create 20 in
+ let _ = really_read fd buffer 0 20 in
+ let size = int_of_string buffer in
+ let buffer = String.create size in
+ let _ = really_read fd buffer 0 size in
+ buffer
+
+let save_tag_table channel t =
+ let t = Array.map (fun s -> Array.of_list (Ptset.Int.elements s)) t in
+ Marshal.to_channel channel t []
+
+let save t str =
+ let fd = Unix.openfile str [ Unix.O_WRONLY;Unix.O_TRUNC;Unix.O_CREAT] 0o644 in
+ let out_c = Unix.out_channel_of_descr fd in
+ let _ = set_binary_mode_out out_c true in
+ output_string out_c magic_string;
+ output_char out_c '\n';
+ output_string out_c version_string;
+ output_char out_c '\n';
+ save_tag_table out_c t.children;
+ save_tag_table out_c t.siblings;
+ save_tag_table out_c t.descendants;
+ save_tag_table out_c t.followings;
+ (* we need to move the fd to the correct position *)
+ flush out_c;
+ ignore (Unix.lseek fd (pos_out out_c) Unix.SEEK_SET);
+ tree_save t.doc fd str;
+ close_out out_c
+;;
+let load_tag_table channel =
+ let table : int array array = Marshal.from_channel channel in
+ Array.map (fun a -> Ptset.Int.from_list (Array.to_list a)) table
+
+let load ?(sample=64) ?(load_text=true) str =
+ let fd = Unix.openfile str [ Unix.O_RDONLY ] 0o644 in
+ let in_c = Unix.in_channel_of_descr fd in
+ let _ = set_binary_mode_in in_c true in
+ let load_table () =
+ (let ms = input_line in_c in if ms <> magic_string then failwith "Invalid index file");
+ (let vs = input_line in_c in if vs <> version_string then failwith "Invalid version file");
+ let c = load_tag_table in_c in
+ let s = load_tag_table in_c in
+ let d = load_tag_table in_c in
+ let f = load_tag_table in_c in
+ c,s,d,f
+ in
+ let c, s, d, f = time ~msg:"Loading tag table"(load_table) () in
+ ignore(Unix.lseek fd (pos_in in_c) Unix.SEEK_SET);
+ let xml_tree = tree_load fd str load_text sample in
+ let () = Tag.init (Obj.magic xml_tree) in
+ let attributes = Ptset.Int.add Tag.attribute d.(Tag.attribute) in
+ let elements = Ptset.Int.add Tag.document_node
+ (Ptset.Int.remove Tag.pcdata
+ (Ptset.Int.diff d.(Tag.document_node) attributes))
+ in
+ let tree = { doc = xml_tree;
+ attributes = attributes;
+ attribute_array = Array.of_list (Ptset.Int.elements attributes);
+ elements = elements;
+ children = c;
+ siblings = s;
+ descendants = d;
+ followings = f
+ }
+ in close_in in_c;
+ tree
+
+
+
+
+let tag_pool t = pool t.doc
+
+let equal a b = a == b
+
+let nts = function
+ -1 -> "Nil"
+ | i -> Printf.sprintf "Node (%i)" i
+
+let dump_node t = nts (Node.to_int t)
+
+
+
+type query_result = { bv : bit_vector;
+ pos : node array;
+ }
+
+external tree_flush : tree -> Unix.file_descr -> unit = "caml_xml_tree_flush"
+let flush t fd = tree_flush t.doc fd
+
+external text_prefix : tree -> string -> query_result = "caml_text_collection_prefix_bv"
+let text_prefix t s = text_prefix t.doc s
+
+external text_suffix : tree -> string -> query_result = "caml_text_collection_suffix_bv"
+let text_suffix t s = text_suffix t.doc s
+
+external text_equals : tree -> string -> query_result = "caml_text_collection_equals_bv"
+let text_equals t s = text_equals t.doc s
+
+external text_contains : tree -> string -> query_result = "caml_text_collection_contains_bv"
+let text_contains t s = text_contains t.doc s
+
+
+module Predicate = Hcons.Make (
+ struct
+ type _t = t
+ type t = (_t -> node -> bool) ref
+ let hash t = Hashtbl.hash t
+ let equal t1 t2 = t1 == t2
+end)
+
+let string_of_query query =
+ match query with
+ | `Prefix -> "starts-with"
+ | `Suffix -> "ends-with"
+ | `Equals -> "equals"
+ | `Contains -> "contains"
+;;
+
+let query_fun = function
+ | `Prefix -> text_prefix
+ | `Suffix -> text_suffix
+ | `Equals -> text_equals
+ | `Contains -> text_contains
+;;
+
+let _pred_cache = Hashtbl.create 17
+;;
+let mk_pred query s =
+ let f = query_fun query in
+ let memo = ref (fun _ _ -> failwith "Undefined") in
+ memo := begin fun tree node ->
+ let results =
+ try Hashtbl.find _pred_cache (query,s) with
+ Not_found ->
+ time ~count:1 ~msg:(Printf.sprintf "Computing text query %s(%s)"
+ (string_of_query query) s)
+ (f tree) s
+ in
+ let bv = results.bv in
+ memo := begin fun _ n ->
+ let b =
+ bit_vector_unsafe_get bv (Node.to_int n)
+ in
+ D_TRACE_(Printf.eprintf "Result of memoized call to query %s is %b for node %i\n" s b (Node.to_int n));
+ b
+ end;
+ let b = bit_vector_unsafe_get bv (Node.to_int node) in
+ D_TRACE_(Printf.eprintf "Result is %b for node %i\n" b (Node.to_int node));
+ b
+ end;
+ Predicate.make memo
+
+
+let full_text_prefix t s = (text_prefix t s).pos
+
+let full_text_suffix t s = (text_suffix t s).pos
+
+let full_text_equals t s = (text_equals t s).pos
+
+let full_text_contains t s = (text_contains t s).pos
+
+let full_text_query q t s =
+ let res = (query_fun q) t s in
+ Hashtbl.replace _pred_cache (q,s) res;
+ res.pos