parsing_cocci/top_level.ml

   1 (*
   2  * Copyright 2010, INRIA, University of Copenhagen
   3  * Julia Lawall, Rene Rydhof Hansen, Gilles Muller, Nicolas Palix
   4  * Copyright 2005-2009, Ecole des Mines de Nantes, University of Copenhagen
   5  * Yoann Padioleau, Julia Lawall, Rene Rydhof Hansen, Henrik Stuart, Gilles Muller, Nicolas Palix
   6  * This file is part of Coccinelle.
   7  *
   8  * Coccinelle is free software: you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation, according to version 2 of the License.
  11  *
  12  * Coccinelle 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.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with Coccinelle.  If not, see <http://www.gnu.org/licenses/>.
  19  *
  20  * The authors reserve the right to distribute this or future versions of
  21  * Coccinelle under other licenses.
  22  *)
  23
  24
  25 (* Reorganize the top level of a rule to be a list of either top-level
  26 declarations or code dots.  A function declaration is always considered top
  27 level.  A statement is always considered code dots.  A variable declaration
  28 is ambiguous.  We use the heuristic that if there are code dots somewhere
  29 else, then the variable declaration is at top level, otherwise it applies
  30 both at top level and to all code. *)
  31
  32 (* This is assumed to be done before compute_lines, and thus the info on a
  33 complex term is assumed to be Ast0.default_info *)
  34
  35 module Ast0 = Ast0_cocci
  36
  37 let top_dots l =
  38   let circle x =
  39     match Ast0.unwrap x with Ast0.Circles(_) -> true | _ -> false in
  40   let star x =
  41     match Ast0.unwrap x with Ast0.Stars(_) -> true | _ -> false in
  42   if List.exists circle l
  43   then Ast0.wrap (Ast0.CIRCLES(l))
  44   else if List.exists star l
  45   then Ast0.wrap (Ast0.STARS(l))
  46   else Ast0.wrap (Ast0.DOTS(l))
  47
  48 let scan_code l =
  49   let statements = ref false in
  50   let rec loop = function
  51       [] -> ([],[])
  52     | (x::xs) as all ->
  53         (match Ast0.unwrap x with
  54           (Ast0.OTHER(code)) ->
  55             (match Ast0.unwrap code with
  56               Ast0.Decl(_) ->
  57                 let (front,rest) = loop xs in
  58                 (code::front,rest)
  59             | _ ->
  60                 statements := true;
  61                 let (front,rest) = loop xs in
  62                 (code::front,rest))
  63         | _ -> ([],all)) in
  64   match loop l with
  65     ([],_) as res -> res
  66   | (code,rest) ->
  67       if !statements = true
  68       then ([Ast0.wrap(Ast0.CODE(top_dots code))],rest)
  69       else
  70         (List.map
  71            (function d ->
  72              match Ast0.unwrap d with
  73                Ast0.Decl(bef,x) -> Ast0.wrap (Ast0.DECL(d))
  74              | _ -> failwith "impossible")
  75            code,
  76          rest)
  77
  78 let rec scan_top_decl = function
  79     [] -> ([],[])
  80   | ((topdecl::rest) as all) ->
  81       (match Ast0.unwrap topdecl with
  82         Ast0.OTHER(_) -> ([],all)
  83       | _ -> let (front,rest) = scan_top_decl rest in (topdecl::front,rest))
  84
  85 (* for debugging *)
  86 let l2c l =
  87   match Ast0.unwrap l with
  88     Ast0.DECL(_) -> "decl"
  89   | Ast0.CODE(_) -> "code"
  90   | Ast0.FILEINFO(_,_) -> "fileinfo"
  91   | Ast0.ERRORWORDS(_) -> "errorwords"
  92   | Ast0.OTHER(_) -> "other"
  93
  94 let rec top_level l =
  95   match scan_code l with
  96     (code,[]) -> code
  97   | (code,rest) ->
  98       (match scan_top_decl rest with
  99         (top_decls,[]) -> code@top_decls
 100       | (top_decls,rest) -> code @ top_decls @ (top_level rest))