Coccinelle release 1.0.0-rc3

[bpt/coccinelle.git] / parsing_cocci / function_prototypes.ml

(*
 * Copyright 2010, INRIA, University of Copenhagen
 * Julia Lawall, Rene Rydhof Hansen, Gilles Muller, Nicolas Palix
 * Copyright 2005-2009, Ecole des Mines de Nantes, University of Copenhagen
 * Yoann Padioleau, Julia Lawall, Rene Rydhof Hansen, Henrik Stuart, Gilles Muller, Nicolas Palix
 * This file is part of Coccinelle.
 *
 * Coccinelle 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, according to version 2 of the License.
 *
 * Coccinelle 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 Coccinelle.  If not, see <http://www.gnu.org/licenses/>.
 *
 * The authors reserve the right to distribute this or future versions of
 * Coccinelle under other licenses.
 *)


module Ast0 = Ast0_cocci
module Ast = Ast_cocci
module V0 = Visitor_ast0
module VT0 = Visitor_ast0_types

type id = Id of string | Meta of Ast.meta_name

let rec get_name name =
  match Ast0.unwrap name with
    Ast0.Id(nm) -> [Id(Ast0.unwrap_mcode nm)]
  | Ast0.MetaId(nm,_,_,_) | Ast0.MetaFunc(nm,_,_)
  | Ast0.MetaLocalFunc(nm,_,_) -> [Meta(Ast0.unwrap_mcode nm)]
  | Ast0.DisjId(_,id_list,_,_) -> List.concat (List.map get_name id_list)
  | Ast0.OptIdent(id) | Ast0.UniqueIdent(id) ->
      get_name id

(* --------------------------------------------------------------------- *)
(* collect all of the functions *)

let brace_to_semi (_,arity,info,mcodekind,pos,adj) =
  let info =
    (* drop column information, so that with -smpl_spacing the semicolon
       will come out right after the close parenthesis *)
    {info with Ast0.pos_info = {info.Ast0.pos_info with Ast0.column = -1}} in
  (";",Ast0.NONE,info,mcodekind,pos,adj)

let collect_function (stm : Ast0.statement) =
  match Ast0.unwrap stm with
    Ast0.FunDecl(_,fninfo,name,lp,params,rp,lbrace,body,rbrace) ->
      let stg =
	match
	  List.filter (function Ast0.FStorage(_) -> true | _ -> false)
	    fninfo with [Ast0.FStorage(s)] -> Some s | _ -> None in
      let ty =
	match
	  List.filter (function Ast0.FType(_) -> true | _ -> false)
	    fninfo with [Ast0.FType(t)] -> Some t | _ -> None in
      List.map
	(function nm ->
	  (nm,stm,
	   Ast0.copywrap stm
	     (Ast0.Decl((Ast0.default_info(),Ast0.context_befaft()),
			Ast0.copywrap stm
			  (Ast0.UnInit
			     (stg,
			      Ast0.copywrap stm
				(Ast0.FunctionType(ty,lp,params,rp)),
			      name,brace_to_semi lbrace))))))
	(get_name name)
  | _ -> []

let collect_functions stmt_dots =
  List.concat (List.map collect_function (Ast0.undots stmt_dots))

let drop_positions =
  let mcode (term,arity,info,mc,_,adj) =
    (term,arity,info,mc,ref [],adj) in
  let donothing r k e = k e in
  let res =
    V0.flat_rebuilder
    mcode mcode mcode mcode mcode mcode mcode mcode mcode mcode mcode mcode
    donothing donothing donothing donothing donothing donothing
    donothing donothing donothing donothing donothing donothing donothing
    donothing donothing in
  res.VT0.rebuilder_rec_statement

let get_all_functions rule =
  let res =
    match Ast0.unwrap rule with
      Ast0.NONDECL(stmt) -> collect_function stmt
    | Ast0.CODE(rule_elem_dots) -> collect_functions rule_elem_dots
    | _ -> [] in
  List.map
    (function (nm,def,vl) ->
      (nm,
       (def,
	drop_positions
	  ((Iso_pattern.rebuild_mcode None).VT0.rebuilder_rec_statement vl))))
    res

(* --------------------------------------------------------------------- *)
(* try to match up the functions *)

(* pass through the - and + functions in lockstep, until one runs out.
Then process the remaining minuses, if any.  If we can find another
function of the same name for either the current - or + function, take that
one.  Otherwise, align the two current ones. *)

let rec align all_minus all_plus =
  let rec loop = function
      ([],_) -> []
    | ((mname,(mdef,mproto))::minus,[]) ->
	(try
	  let (_,pproto) = List.assoc mname all_plus in
	  (mname,mdef,mproto,Some pproto)::(loop (minus,[]))
	with Not_found -> (mname,mdef,mproto,None)::(loop (minus, [])))
    | ((mname,(mdef,mproto))::minus,(pname,(pdef,pproto))::plus) ->
	if mname = pname
	then (mname,mdef,mproto,Some pproto)::(loop (minus, []))
	else
	  (try
	    let (_,pproto_for_minus) = List.assoc mname all_plus in
	    (try
	      let _ = List.assoc mname all_plus in
	      (* protos that match both *)
	      (mname,mdef,mproto,Some pproto_for_minus)::(loop (minus, plus))
	    with Not_found ->
	      (* proto that matches only minus *)
	      (mname,mdef,mproto,Some pproto_for_minus)::
	      (loop (minus, ((pname,(pdef,pproto))::plus))))
	  with Not_found ->
	    (try
	      let _ = List.assoc mname all_plus in
	      (* proto only for plus *)
	      (mname,mdef,mproto,None)::(loop (minus, plus))
	    with Not_found ->
	      (* protos for no one *)
	      (mname,mdef,mproto,Some pproto)::(loop (minus, plus)))) in
  List.filter changed_proto (loop (all_minus, all_plus))

(* --------------------------------------------------------------------- *)

and strip =
  let donothing r k e =
    {(Ast0.wrap (Ast0.unwrap (k e))) with
      Ast0.mcodekind = ref  (Ast0.PLUS Ast.ONE)} in
  let mcode (mc,_,_,_,_,_) =
    (mc,Ast0.NONE,Ast0.default_info(),Ast0.PLUS Ast.ONE,
     ref [],-1) in

  (* need a case for everything that has an unvisited component and can be in
     a function prototype *)

  let ident r k e =
    donothing r k
      (Ast0.rewrap e
	 (match Ast0.unwrap e with
	   Ast0.MetaId(nm,constraints,seed,pure) ->
	     Ast0.MetaId(nm,constraints,seed,Ast0.Pure)
	 | Ast0.MetaFunc(nm,constraints,pure) ->
	     Ast0.MetaFunc(nm,constraints,Ast0.Pure)
	 | Ast0.MetaLocalFunc(nm,constraints,pure) ->
	     Ast0.MetaLocalFunc(nm,constraints,Ast0.Pure)
	 | e -> e)) in

  let typeC r k e =
    donothing r k
      (Ast0.rewrap e
	 (match Ast0.unwrap e with
	   Ast0.MetaType(nm,pure) -> Ast0.MetaType(nm,Ast0.Pure)
	 | e -> e)) in

  let param r k e =
    donothing r k
      (Ast0.rewrap e
	 (match Ast0.unwrap e with
	   Ast0.MetaParam(nm,pure) ->
	     Ast0.MetaParam(nm,Ast0.Pure)
	 | Ast0.MetaParamList(nm,lenname,pure) ->
	     Ast0.MetaParamList(nm,lenname,Ast0.Pure)
	 | e -> e)) in

  V0.flat_rebuilder
    mcode mcode mcode mcode mcode mcode mcode mcode mcode mcode mcode mcode
    donothing donothing donothing donothing donothing donothing
    ident donothing typeC donothing param donothing donothing
    donothing donothing

and changed_proto = function
    (mname,mdef,mproto,None) -> true
  | (mname,mdef,mproto,Some pproto) ->
      not ((strip.VT0.rebuilder_rec_statement mproto) =
	   (strip.VT0.rebuilder_rec_statement pproto))

(* --------------------------------------------------------------------- *)
(* make rules *)

let rec drop_param_name p =
  Ast0.rewrap p
    (match Ast0.unwrap p with
      Ast0.Param(p,_) -> Ast0.Param(p,None)
    | Ast0.OptParam(p) -> Ast0.OptParam(drop_param_name p)
    | Ast0.UniqueParam(p) -> Ast0.UniqueParam(p)
    | p -> p)

let drop_names dec =
  let dec = (Iso_pattern.rebuild_mcode None).VT0.rebuilder_rec_statement dec in
  match Ast0.unwrap dec with
    Ast0.Decl(info,uninit) ->
      (match Ast0.unwrap uninit with
	Ast0.UnInit(stg,typ,name,sem) ->
	  (match Ast0.unwrap typ with
	    Ast0.FunctionType(ty,lp,params,rp) ->
	      let params =
		match Ast0.unwrap params with
		  Ast0.DOTS(l) ->
		    Ast0.rewrap params (Ast0.DOTS(List.map drop_param_name l))
		| Ast0.CIRCLES(l) ->
		    Ast0.rewrap params
		      (Ast0.CIRCLES(List.map drop_param_name l))
		| Ast0.STARS(l) -> failwith "unexpected stars" in
	      Ast0.rewrap dec
		(Ast0.Decl
		   (info,
		    Ast0.rewrap uninit
		      (Ast0.UnInit
			 (stg,
			  Ast0.rewrap typ
			    (Ast0.FunctionType(ty,lp,params,rp)),
			  name,sem))))
	  | _ -> failwith "function prototypes: unexpected type")
      |	_ -> failwith "unexpected declaration")
  | _ -> failwith "unexpected term"

let ct = ref 0

let new_name name =
  let n = !ct in
  ct := !ct + 1;
  name^"__"^(string_of_int n)

let rec rename_param old_name all param =
  match Ast0.unwrap param with
    Ast0.Param(ty,Some id) when all ->
      (match Ast0.unwrap id with
	Ast0.MetaId
	  (((_,name),arity,info,mcodekind,pos,adj),constraints,seed,pure) ->
	  let nm = ("__no_name__",new_name name) in
	  let new_id =
	    Ast0.rewrap id
	      (Ast0.MetaId
		 ((nm,arity,info,mcodekind,pos,adj),constraints,seed,
		  Ast0.Pure)) in
	  ([Ast.MetaIdDecl(Ast.NONE,nm)],
	   Ast0.rewrap param (Ast0.Param(ty,Some new_id)))
      |	_ -> ([],param))
  | Ast0.Pdots(d) ->
      let nm = (old_name,new_name "__P") in
      let nml = (old_name,new_name "__n") in
      let new_id =
	Ast0.rewrap param
	  (Ast0.MetaParamList(Ast0.rewrap_mcode d nm,
			      Ast0.MetaListLen (Ast0.rewrap_mcode d nml),
			      Ast0.Pure)) in
      ([Ast.MetaParamListDecl(Ast.NONE,nm,Ast.MetaLen nml);
	 Ast.MetaListlenDecl(nml)],
       new_id)
  | Ast0.OptParam(p) ->
      let (metavars,p) = rename_param old_name all p in
      (metavars,Ast0.rewrap param (Ast0.OptParam(p)))
  | Ast0.UniqueParam(p) ->
      let (metavars,p) = rename_param old_name all p in
      (metavars,Ast0.rewrap param (Ast0.UniqueParam(p)))
  | _ -> ([],param)

(* try to convert names in the - parameter list to new metavariables, to
account for spelling mistakes on the part of the programmer *)
let fresh_names old_name mdef dec =
  let res = ([],[],dec,mdef) in
  match Ast0.unwrap dec with
    Ast0.Decl(info,uninit) ->
      (match Ast0.unwrap uninit with
	Ast0.UnInit(stg,typ,name,sem) ->
	  (match Ast0.unwrap typ with
	    Ast0.FunctionType(ty,lp,params,rp) ->
	      let (metavars,newdec) =
		let (metavars,l) =
		  List.split
		    (List.map (rename_param old_name true)
		       (Ast0.undots params)) in
		(List.concat metavars,
		 Ast0.rewrap dec
		   (Ast0.Decl
		      (info,
		       Ast0.rewrap uninit
			 (Ast0.UnInit
			    (stg,
			     Ast0.rewrap typ
			       (Ast0.FunctionType
				  (ty,lp,Ast0.rewrap params (Ast0.DOTS(l)),
				   rp)),
			     name,sem))))) in
	      let (def_metavars,newdef) =
		match Ast0.unwrap mdef with
		  Ast0.FunDecl(x,fninfo,name,lp,params,rp,lb,body,rb) ->
		    let (def_metavars,def_l) =
		      List.split
			(List.map (rename_param old_name false)
			   (Ast0.undots params)) in
		    (List.concat def_metavars,
		     Ast0.rewrap mdef
		       (Ast0.FunDecl(x,fninfo,name,lp,
				     Ast0.rewrap params (Ast0.DOTS(def_l)),
				     rp,lb,body,rb)))
		   | _ -> failwith "unexpected function definition" in
	      (metavars,def_metavars,newdec,newdef)
	  | _ -> res)
      |	_ -> res)
  | _ -> res

(* since there is no + counterpart, the function must be completely deleted *)
let no_names dec =
  match Ast0.unwrap dec with
    Ast0.Decl(info,uninit) ->
      (match Ast0.unwrap uninit with
	Ast0.UnInit(stg,typ,name,sem) ->
	  (match Ast0.unwrap typ with
	    Ast0.FunctionType(ty,lp,params,rp) ->
	      Ast0.rewrap dec
		(Ast0.Decl
		   (info,
		    Ast0.rewrap uninit
		      (Ast0.UnInit
			 (stg,
			  Ast0.rewrap typ
			    (Ast0.FunctionType
			       (ty,lp,
				Ast0.rewrap params
				  (let info = Ast0.get_info params in
				  let mcodekind =
				    (* use the mcodekind of an atomic minused
				       thing *)
				    Ast0.get_mcode_mcodekind lp in
				  let pdots =
				    ("...",Ast0.NONE,info,mcodekind,
				     ref [],-1) in
				  Ast0.DOTS
				    ([Ast0.rewrap params
					 (Ast0.Pdots(pdots))])),
				rp)),
			  name,sem))))
	  | _ -> dec)
      |	_ -> dec)
  | _ -> dec

let mkcode proto =
  Ast0.copywrap proto (Ast0.CODE(Ast0.copywrap proto (Ast0.DOTS [proto])))

let merge mproto pproto =
  let mproto = Compute_lines.compute_lines true [mkcode mproto] in
  let pproto = Compute_lines.compute_lines true [mkcode pproto] in
  let (m,p) = List.split(Context_neg.context_neg mproto pproto) in
  Insert_plus.insert_plus m p true (* no isos for protos *);
  (* convert to ast so that the + code will fall down to the tokens
     and off the artificially added Ast0.CODE *)
  let mproto = Ast0toast.ast0toast_toplevel (List.hd mproto) in
  (* clean up the wrapping added above *)
  match Ast.unwrap mproto with
    Ast.CODE mproto -> List.hd (Ast.undots mproto)
  | _ -> failwith "not possible"

let make_rule rule_name = function
    (mname,mdef,mproto,Some pproto) ->
      let (metavars,mdef_metavars,mproto,mdef) =
	fresh_names rule_name mdef mproto in
      let no_name_mproto = drop_names mproto in
      let no_name_pproto = drop_names pproto in
      (metavars,mdef_metavars,
       [merge mproto pproto; merge no_name_mproto no_name_pproto],mdef)
  | (mname,mdef,mproto,None) ->
      ([],[],[Ast0toast.statement(no_names mproto)],mdef)

(* --------------------------------------------------------------------- *)

let reinsert mdefs minus =
  let table =
    List.map
      (function x ->
	match Ast0.unwrap x with
	  Ast0.FunDecl(_,fninfo,name,lp,params,rp,lbrace,body,rbrace) ->
	    (name,x)
	| _ -> failwith "bad mdef")
      mdefs in
  List.map
    (function x ->
      match Ast0.unwrap x with
	Ast0.NONDECL(stmt) ->
	  (match Ast0.unwrap stmt with
	    Ast0.FunDecl(_,fninfo,name,lp,params,rp,lbrace,body,rbrace) ->
	      (try Ast0.rewrap x (Ast0.NONDECL(List.assoc name table))
	      with Not_found -> x)
	  | _ -> x)
      | Ast0.CODE(rule_elem_dots) ->
	  (* let's hope there are no functions in here... *)
	  x
      |	_ -> x)
    minus

(* --------------------------------------------------------------------- *)
(* entry point *)

let rec split4 = function
    [] -> ([],[],[],[])
  | (a,b,c,d)::rest ->
      let (ax,bx,cx,dx) = split4 rest in (a::ax,b::bx,c::cx,d::dx)

let mk_ast_code proto =
  Ast.rewrap proto (Ast.CODE(Ast.rewrap proto (Ast.DOTS [proto])))

let process rule_name rule_metavars dropped_isos minus plus ruletype =
  let minus_functions = List.concat (List.map get_all_functions minus) in
  match minus_functions with
    [] -> ((rule_metavars,minus),None)
  | _ ->
      let plus_functions =
	List.concat (List.map get_all_functions plus) in
      let protos = align minus_functions plus_functions in
      let (metavars,mdef_metavars,rules,mdefs) =
	split4(List.map (make_rule rule_name) protos) in
      let metavars = List.concat metavars in
      let mdef_metavars = (List.concat mdef_metavars) @ rule_metavars in
      let rules = List.concat rules in
      let minus = reinsert mdefs minus in
      match rules with
	[] -> ((rule_metavars,minus),None)
      | [x] ->
	  (* probably not possible, since there is always the version with
	     variables and the version without *)
	  ((mdef_metavars,minus),
	   Some
	     (metavars,
	      Ast.CocciRule
		("proto for "^rule_name,
		 (Ast.Dep rule_name,dropped_isos,Ast.Forall),
		 [mk_ast_code x],
		 [false],ruletype)))
      |	x::_ ->
	  let drules =
	    List.map (function x -> Ast.rewrap x (Ast.DOTS [x])) rules in
	  let res =
            Ast.CocciRule
	    ("proto for "^rule_name,
	     (Ast.Dep rule_name,dropped_isos,Ast.Forall),
	     [mk_ast_code (Ast.rewrap x (Ast.Disj drules))],
	     [false],ruletype) in
	  ((mdef_metavars,minus),Some(metavars,res))