X-Git-Url: http://matita.cs.unibo.it/gitweb/?p=helm.git;a=blobdiff_plain;f=components%2Fregistry%2Fhelm_registry.ml;fp=components%2Fregistry%2Fhelm_registry.ml;h=fd0df50136add3246c4e2f1aff7734fad05c0d7f;hp=0000000000000000000000000000000000000000;hb=f61af501fb4608cc4fb062a0864c774e677f0d76;hpb=58ae1809c352e71e7b5530dc41e2bfc834e1aef1

diff --git a/components/registry/helm_registry.ml b/components/registry/helm_registry.ml
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+++ b/components/registry/helm_registry.ml
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+(* Copyright (C) 2004-2005, HELM Team.
+ * 
+ * This file is part of HELM, an Hypertextual, Electronic
+ * Library of Mathematics, developed at the Computer Science
+ * Department, University of Bologna, Italy.
+ * 
+ * HELM is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ * 
+ * HELM is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HELM; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA  02111-1307, USA.
+ * 
+ * For details, see the HELM World-Wide-Web page,
+ * http://helm.cs.unibo.it/
+ *)
+
+(* $Id$ *)
+
+open Printf
+
+let debug = false
+let debug_print s =
+  if debug then prerr_endline ("Helm_registry debugging: " ^ (Lazy.force s))
+
+  (** <helpers> *)
+
+let list_uniq l =
+  let rec aux last_element = function
+    | [] -> []
+    | hd :: tl ->
+        (match last_element with
+        | Some elt when elt = hd -> aux last_element tl
+        | _ -> hd :: aux (Some hd) tl)
+  in
+  aux None l
+
+let starts_with prefix =
+(*
+  let rex = Str.regexp (Str.quote prefix) in
+  fun s -> Str.string_match rex s 0
+*)
+  let prefix_len = String.length prefix in
+  fun s ->
+    try
+      String.sub s 0 prefix_len = prefix
+    with Invalid_argument _ -> false
+
+let hashtbl_keys tbl = Hashtbl.fold (fun k _ acc -> k :: acc) tbl []
+let hashtbl_pairs tbl = Hashtbl.fold (fun k v acc -> (k,v) :: acc) tbl []
+
+  (** </helpers> *)
+
+exception Malformed_key of string
+exception Key_not_found of string
+exception Cyclic_definition of string
+exception Type_error of string (* expected type, value, msg *)
+exception Parse_error of string * int * int * string  (* file, line, col, msg *)
+
+  (* root XML tag: used by save_to, ignored by load_from *)
+let root_tag = "helm_registry"
+
+let magic_size = 127
+
+let backup_registry registry = Hashtbl.copy registry
+let restore_registry backup registry =
+  Hashtbl.clear registry;
+  Hashtbl.iter (fun key value -> Hashtbl.add registry key value) backup
+
+  (* as \\w but:
+   * - no sequences of '_' longer than 1 are permitted
+   *)
+let valid_step_rex_raw = "[a-zA-Z0-9]+\\(_[a-z0A-Z-9]+\\)*"
+let valid_key_rex_raw =
+  sprintf "%s\\(\\.%s\\)*" valid_step_rex_raw valid_step_rex_raw
+let valid_key_rex = Str.regexp ("^" ^ valid_key_rex_raw ^ "$")
+let interpolated_key_rex = Str.regexp ("\\$(" ^ valid_key_rex_raw ^ ")")
+let dot_rex = Str.regexp "\\."
+let spaces_rex = Str.regexp "[ \t\n\r]+"
+let heading_spaces_rex = Str.regexp "^[ \t\n\r]+"
+let margin_blanks_rex =
+  Str.regexp "^\\([ \t\n\r]*\\)\\([^ \t\n\r]*\\)\\([ \t\n\r]*\\)$"
+
+let strip_blanks s = Str.global_replace margin_blanks_rex "\\2" s
+
+let split s =
+  (* trailing blanks are removed per default by split *)
+  Str.split spaces_rex (Str.global_replace heading_spaces_rex "" s)
+let merge l = String.concat " " l
+
+let handle_type_error f x =
+  try f x with exn -> raise (Type_error (Printexc.to_string exn))
+
+  (** marshallers/unmarshallers *)
+let string x = x
+let int = handle_type_error int_of_string
+let float = handle_type_error float_of_string
+let bool = handle_type_error bool_of_string
+let of_string x = x
+let of_int = handle_type_error string_of_int
+let of_float = handle_type_error string_of_float
+let of_bool = handle_type_error string_of_bool
+
+(* FG *)
+let pair fst_unmarshaller snd_unmarshaller v =
+  match Str.split spaces_rex v with
+  | [fst; snd] -> fst_unmarshaller fst, snd_unmarshaller snd
+  | _ -> raise (Type_error "not a pair")
+
+  (* escapes for xml configuration file *)
+let (escape, unescape) =
+  let (in_enc, out_enc) = (`Enc_utf8, `Enc_utf8) in
+  (Netencoding.Html.encode ~in_enc ~out_enc (),
+   Netencoding.Html.decode ~in_enc ~out_enc ~entity_base:`Xml ())
+
+let key_is_valid key =
+  if not (Str.string_match valid_key_rex key 0) then
+    raise (Malformed_key key)
+
+let set' ?(replace=false) registry ~key ~value =
+  debug_print (lazy(sprintf "Setting (replace: %b) %s = %s" replace key value));
+  key_is_valid key;
+  let add_fun = if replace then Hashtbl.replace else Hashtbl.add in
+  add_fun registry key value
+
+let unset registry = Hashtbl.remove registry
+
+let env_var_of_key s = String.uppercase (Str.global_replace dot_rex "_" s)
+
+let singleton = function
+  | [] ->
+      raise (Type_error ("empty list value found where singleton was expected"))
+  | hd :: _ -> hd
+
+let get registry key =
+  let rec aux stack key =
+    key_is_valid key;
+    if List.mem key stack then begin
+      let msg = (String.concat " -> " (List.rev stack)) ^ " -> " ^ key in
+      raise (Cyclic_definition msg)
+    end;
+      (* internal value *)
+    let registry_values = List.rev (Hashtbl.find_all registry key) in
+    let env_value = (* environment value *)
+      try
+        Some (Sys.getenv (env_var_of_key key))
+      with Not_found -> None
+    in
+    let values = (* resulting value *)
+      match registry_values, env_value with
+      | _, Some env -> [env]
+      | [], None ->
+          (try
+            [ Sys.getenv key ]
+          with Not_found -> raise (Key_not_found key))
+      | values, None -> values
+    in
+    List.map (interpolate (key :: stack)) values
+  and interpolate stack value =
+    Str.global_substitute interpolated_key_rex
+      (fun s ->
+        let matched = Str.matched_string s in
+          (* "$(var)" -> "var" *)
+        let key = String.sub matched 2 (String.length matched - 3) in
+        singleton (aux stack key))
+      value
+  in
+  List.map strip_blanks (aux [] key)
+
+let has registry key = Hashtbl.mem registry key
+
+let get_typed registry unmarshaller key =
+  let value = singleton (get registry key) in
+  unmarshaller value
+
+let set_typed registry marshaller ~key ~value =
+  set' ~replace:true registry ~key ~value:(marshaller value)
+
+let get_opt registry unmarshaller key =
+  try
+    Some (unmarshaller (singleton (get registry key)))
+  with Key_not_found _ -> None
+
+let get_opt_default registry unmarshaller ~default key =
+  match get_opt registry unmarshaller key with
+  | None -> default
+  | Some v -> v
+
+let set_opt registry marshaller ~key ~value =
+  match value with
+  | None -> unset registry key
+  | Some value -> set' ~replace:true registry ~key ~value:(marshaller value)
+
+let get_list registry unmarshaller key =
+  try
+    let tmp = get registry key in
+    let rc = List.map unmarshaller tmp in
+    rc
+  with Key_not_found _ -> []
+
+(* FG *)
+let get_pair registry fst_unmarshaller snd_unmarshaller =
+  get_typed registry (pair fst_unmarshaller snd_unmarshaller) 
+
+let set_list registry marshaller ~key ~value =
+  (* since ocaml hash table are crazy... *)
+  while Hashtbl.mem registry key do
+    Hashtbl.remove registry key
+  done;
+  List.iter (fun v -> set' registry ~key ~value:(marshaller v)) value
+
+type xml_tree =
+  | Cdata of string
+  | Element of string * (string * string) list * xml_tree list
+
+let dot_RE = Str.regexp "\\."
+
+let xml_tree_of_registry registry =
+  let has_child name elements =
+    List.exists
+      (function
+        | Element (_, ["name", name'], _) when name = name' -> true
+        | _ -> false)
+      elements
+  in
+  let rec get_child name = function
+    | [] -> assert false
+    | (Element (_, ["name", name'], _) as child) :: tl when name = name' ->
+        child, tl
+    | hd :: tl ->
+        let child, rest = get_child name tl in
+        child, hd :: rest
+  in
+  let rec add_key path value tree =
+    match path, tree with
+    | [key], Element (name, attrs, children) ->
+        Element (name, attrs,
+          Element ("key", ["name", key],
+            [Cdata (strip_blanks value)]) :: children)
+    | dir :: path, Element (name, attrs, children) ->
+        if has_child dir children then
+          let child, rest = get_child dir children in
+          Element (name, attrs, add_key path value child :: rest)
+        else
+          Element (name, attrs,
+            ((add_key path value (Element ("section", ["name", dir], [])))
+              :: children))
+    | _ -> assert false
+  in
+  Hashtbl.fold
+    (fun k v tree -> add_key ((Str.split dot_RE k)) v tree)
+    registry
+    (Element (root_tag, [], []))
+
+let rec stream_of_xml_tree = function
+  | Cdata s -> Xml.xml_cdata s
+  | Element (name, attrs, children) ->
+      Xml.xml_nempty name
+        (List.map (fun (n, v) -> (None, n, v)) attrs)
+        (stream_of_xml_trees children)
+and stream_of_xml_trees = function
+  | [] -> [< >]
+  | hd :: tl -> [< stream_of_xml_tree hd; stream_of_xml_trees tl >]
+
+let save_to registry fname =
+  let token_stream = stream_of_xml_tree (xml_tree_of_registry registry) in
+  let oc = open_out fname in
+  Xml.pp_to_outchan token_stream oc;
+  close_out oc
+
+let rec load_from_absolute ?path registry fname =
+  let _path = ref (match path with None -> [] | Some p -> p)in
+    (* <section> elements entered so far *)
+  let in_key = ref false in (* have we entered a <key> element? *)
+  let cdata = ref "" in     (* collected cdata (inside <key> *)
+  let push_path name = _path := name :: !_path in
+  let pop_path () = _path := List.tl !_path in
+  let start_element tag attrs =
+    match tag, attrs with
+    | "section", ["name", name] -> push_path name
+    | "key", ["name", name] -> in_key := true; push_path name
+    | "helm_registry", _ -> ()
+    | "include", ["href", fname] ->
+        debug_print (lazy ("including file " ^ fname));
+        load_from_absolute ~path:!_path registry fname
+    | tag, _ ->
+        raise (Parse_error (fname, ~-1, ~-1,
+          (sprintf "unexpected element <%s> or wrong attribute set" tag)))
+  in
+  let end_element tag =
+    match tag with
+    | "section" -> pop_path ()
+    | "key" ->
+        let key = String.concat "." (List.rev !_path) in
+        set' registry ~key ~value:!cdata;
+        cdata := "";
+        in_key := false;
+        pop_path ()
+    | "include" | "helm_registry" -> ()
+    | _ -> assert false
+  in
+  let character_data text =
+    if !in_key then cdata := !cdata ^ text
+  in
+  let callbacks = {
+    XmlPushParser.default_callbacks with
+      XmlPushParser.start_element = Some start_element;
+      XmlPushParser.end_element = Some end_element;
+      XmlPushParser.character_data = Some character_data;
+  } in
+  let xml_parser = XmlPushParser.create_parser callbacks in
+  let backup = backup_registry registry in
+(*   if path = None then Hashtbl.clear registry; *)
+  try
+    XmlPushParser.parse xml_parser (`File fname)
+  with exn ->
+    restore_registry backup registry;
+    raise exn
+
+let load_from registry ?path fname =
+  if Filename.is_relative fname then begin
+    let no_file_found = ref true in
+    let path =
+      match path with
+      | Some path -> path (* path given as argument *)
+      | None -> [ Sys.getcwd () ] (* no path given, try with cwd *)
+    in
+    List.iter
+      (fun dir ->
+        let conffile = dir ^ "/" ^ fname in
+        if Sys.file_exists conffile then begin
+          no_file_found := false;
+          load_from_absolute registry conffile
+        end)
+       path;
+    if !no_file_found then
+      failwith (sprintf
+        "Helm_registry.init: no configuration file named %s in [ %s ]"
+        fname (String.concat "; " path))
+  end else
+    load_from_absolute registry fname
+
+let fold registry ?prefix ?(interpolate = true) f init =
+  let value_of k v =
+    if interpolate then singleton (get registry k) else strip_blanks v
+  in
+  match prefix with
+  | None -> Hashtbl.fold (fun k v acc -> f acc k (value_of k v)) registry init
+  | Some s ->
+      let key_matches = starts_with (s ^ ".") in
+      let rec fold_filter acc = function
+        | [] -> acc
+        | (k,v) :: tl when key_matches k ->
+            fold_filter (f acc k (value_of k v)) tl
+        | _ :: tl -> fold_filter acc tl
+      in
+      fold_filter init (hashtbl_pairs registry)
+
+let iter registry ?prefix ?interpolate f =
+  fold registry ?prefix ?interpolate (fun _ k v -> f k v) ()
+let to_list registry ?prefix ?interpolate () =
+  fold registry ?prefix ?interpolate (fun acc k v -> (k, v) :: acc) []
+
+let ls registry prefix =
+  let prefix = prefix ^ "." in
+  let prefix_len = String.length prefix in
+  let key_matches = starts_with prefix in
+  let matching_keys = (* collect matching keys' _postfixes_ *)
+    fold registry
+      (fun acc key _ ->
+        if key_matches key then
+          String.sub key prefix_len (String.length key - prefix_len) :: acc
+        else
+          acc)
+      []
+  in
+  let (sections, keys) =
+    List.fold_left
+      (fun (sections, keys) postfix ->
+        match Str.split dot_rex postfix with
+        | [key] -> (sections, key :: keys)
+        | hd_key :: _ ->  (* length > 1 => nested section found *)
+            (hd_key :: sections, keys)
+        | _ -> assert false)
+      ([], []) matching_keys
+  in
+  (list_uniq (List.sort Pervasives.compare sections), keys)
+
+(** {2 API implementation}
+ * functional methods above are wrapped so that they work on a default
+ * (imperative) registry*)
+
+let default_registry = Hashtbl.create magic_size
+
+let get key = singleton (get default_registry key)
+let set = set' ~replace:true default_registry
+let has = has default_registry
+let fold ?prefix ?interpolate f init =
+  fold default_registry ?prefix ?interpolate f init
+let iter = iter default_registry
+let to_list = to_list default_registry
+let ls = ls default_registry
+let get_typed unmarshaller = get_typed default_registry unmarshaller
+let get_opt unmarshaller = get_opt default_registry unmarshaller
+let get_opt_default unmarshaller = get_opt_default default_registry unmarshaller
+let get_list unmarshaller = get_list default_registry unmarshaller
+let get_pair unmarshaller = get_pair default_registry unmarshaller
+let set_typed marshaller = set_typed default_registry marshaller
+let set_opt unmarshaller = set_opt default_registry unmarshaller
+let set_list marshaller = set_list default_registry marshaller
+let unset = unset default_registry
+let save_to = save_to default_registry
+let load_from = load_from default_registry
+let clear () = Hashtbl.clear default_registry
+
+let get_string = get_typed string
+let get_int = get_typed int
+let get_float = get_typed float
+let get_bool = get_typed bool
+let set_string = set_typed of_string
+let set_int = set_typed of_int
+let set_float = set_typed of_float
+let set_bool = set_typed of_bool
+