1 (* Copyright (C) 2002-2008 Yoann Padioleau
3 * This program is free software; you can redistribute it and/or
4 * modify it under the terms of the GNU General Public License (GPL)
5 * version 2 as published by the Free Software Foundation.
7 * This program is distributed in the hope that it will be useful,
8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10 * file license.txt for more details.
14 (* Tricks used to handle the ambiguity in the grammar with the typedef
15 * which impose a cooperation between the lexer and the parser.
17 * An example by hughes casse: "in the symbol table, local
18 * definition must replace type definition in order to correctly parse
19 * local variable in functions body. This is the only way to correctly
20 * handle this kind of exception, that is,
22 * typedef ... ID; int f(int *p) {int ID; return (ID) * *p;} If ID
23 * isn't overload, last expression is parsed as a type cast, if it
24 * isn't, this a multiplication."
26 * Why parse_typedef_fix2 ? Cos when introduce new variable, for
27 * instance when declare parameters for a function such as int var_t,
28 * then the var_t must not be lexed as a typedef, so we must disable
29 * temporaly the typedef mechanism to allow variable with same name as
32 (* parse_typedef_fix *)
33 let _handle_typedef = ref true
35 (* parse_typedef_fix2 *)
36 let enable_typedef () = _handle_typedef := true
37 let disable_typedef () = _handle_typedef := false
39 let is_enabled_typedef () = !_handle_typedef
44 type identkind
= TypeDefI
| IdentI
46 (* Ca marche ce code ? on peut avoir un typedef puis un ident puis
47 * un typedef nested ? oui car Hashtbl (dans scoped_h_env) gere l'historique.
49 * oldsimple: but slow, take 2 secondes on some C files
50 * let (typedef: typedef list list ref) = ref [[]]
52 let (_typedef
: (string, identkind
) Common.scoped_h_env
ref) =
53 ref (Common.empty_scoped_h_env
())
55 let is_typedef s
= if !_handle_typedef then
56 (match (Common.optionise
(fun () -> Common.lookup_h_env s
!_typedef
)) with
57 | Some TypeDefI
-> true
58 | Some IdentI
-> false
63 let new_scope() = Common.new_scope_h _typedef
64 let del_scope() = Common.del_scope_h _typedef
66 let add_typedef s
= Common.add_in_scope_h _typedef
(s
, TypeDefI
)
67 let add_ident s
= Common.add_in_scope_h _typedef
(s
, IdentI
)
69 let add_typedef_root s
=
70 if !Flag_parsing_c.add_typedef_root
72 Hashtbl.add
!_typedef
.scoped_h s TypeDefI
73 else add_typedef s
(* have far more .failed without this *)
76 (* Used by parse_c when do some error recovery. The parse error may
77 * have some bad side effects on typedef hash, so recover this.
79 let _old_state = ref (Common.clone_scoped_h_env
!_typedef
)
81 let save_typedef_state () =
82 _old_state := Common.clone_scoped_h_env
!_typedef
84 let restore_typedef_state () =
85 _typedef
:= !_old_state
98 let is_top_or_struct = function
105 mutable context_stack
: context
Common.stack
;
108 let default_hint () = {
109 context_stack
= [InTopLevel
];
112 let _lexer_hint = ref (default_hint())
114 let current_context () = List.hd
!_lexer_hint.context_stack
115 let push_context ctx
=
116 !_lexer_hint.context_stack
<- ctx
::!_lexer_hint.context_stack
118 !_lexer_hint.context_stack
<- List.tl
!_lexer_hint.context_stack
122 let lexer_reset_typedef () =
124 _handle_typedef := true;
125 _typedef
:= Common.empty_scoped_h_env
();
126 _lexer_hint := (default_hint ());