infer_clone/infer/src/backend/exe_env.ml

(*
 * Copyright (c) 2009 - 2013 Monoidics ltd.
 * Copyright (c) 2013 - present Facebook, Inc.
 * All rights reserved.
 *
 * This source code is licensed under the BSD style license found in the
 * LICENSE file in the root directory of this source tree. An additional grant
 * of patent rights can be found in the PATENTS file in the same directory.
 *)

open! IStd
open! PVariant
module Hashtbl = Caml.Hashtbl

(** Support for Execution environments *)

module L = Logging
module F = Format

(** per-file data: type environment and cfg *)
type file_data =
  { source: SourceFile.t;
    tenv_file: DB.filename;
    mutable tenv: Tenv.t option;
    cfg_file: DB.filename;
    mutable cfg: Cfg.cfg option;
  }

(** get the path to the tenv file, which either one tenv file per source file or a global tenv file *)
let tenv_filename file_base =
  let per_source_tenv_filename = DB.filename_add_suffix file_base ".tenv" in
  if Sys.file_exists (DB.filename_to_string per_source_tenv_filename) = `Yes then
    per_source_tenv_filename
  else
    DB.global_tenv_fname

module FilenameHash = Hashtbl.Make(
  struct
    type t = DB.filename
    let equal file1 file2 = DB.equal_filename file1 file2
    let hash = Hashtbl.hash
  end)

(** create a new file_data *)
let new_file_data source cg_fname =
  let file_base = DB.chop_extension cg_fname in
  let tenv_file = tenv_filename file_base in
  let cfg_file = DB.filename_add_suffix file_base ".cfg" in
  { source = source;
    tenv_file = tenv_file;
    tenv = None; (* Sil.load_tenv_from_file tenv_file *)
    cfg_file = cfg_file;
    cfg = None; (* Cfg.load_cfg_from_file cfg_file *)
  }

let create_file_data table source cg_fname =
  match FilenameHash.find table cg_fname with
  | file_data ->
      file_data
  | exception Not_found ->
      let file_data = new_file_data source cg_fname in
      FilenameHash.add table cg_fname file_data;
      file_data

(** execution environment *)
type t =
  { cg: Cg.t; (** global call graph *)
    proc_map: file_data Typ.Procname.Hash.t; (** map from procedure name to file data *)
    file_map: file_data FilenameHash.t; (** map from cg fname to file data *)
    mutable source_files : SourceFile.Set.t; (** Source files in the execution environment *)
  }

(** initial state, used to add cg's *)
type initial = t

(** create a new execution environment *)
let create () =
  { cg = Cg.create (SourceFile.invalid __FILE__);
    proc_map = Typ.Procname.Hash.create 17;
    file_map = FilenameHash.create 1;
    source_files = SourceFile.Set.empty;
  }

(** add call graph from fname in the spec db,
    with relative tenv and cfg, to the execution environment *)
let add_cg (exe_env: t) (source_dir : DB.source_dir) =
  let cg_fname = DB.source_dir_get_internal_file source_dir ".cg" in
  match Cg.load_from_file cg_fname with
  | None ->
      L.internal_error "Error: cannot load %s@." (DB.filename_to_string cg_fname)
  | Some cg ->
      let source = Cg.get_source cg in
      exe_env.source_files <- SourceFile.Set.add source exe_env.source_files;
      let defined_procs = Cg.get_defined_nodes cg in
      let duplicate_procs_to_print = List.filter_map defined_procs
          ~f:(fun pname ->
              (match AttributesTable.find_file_capturing_procedure ~cache:false pname with
               | None -> None
               | Some (source_captured, origin) ->
                   let multiply_defined = SourceFile.compare source source_captured <> 0 in
                   if multiply_defined then Cg.remove_node_defined cg pname;
                   if multiply_defined && origin <> `Include then
                     Some (pname, source_captured)
                   else None
              )) in
      (if Config.dump_duplicate_symbols then
         Out_channel.with_file (Config.results_dir ^/ Config.duplicates_filename)
           ~append:true ~perm:0o666 ~f:(fun outc ->
               let fmt = F.formatter_of_out_channel outc in
               List.iter duplicate_procs_to_print ~f:(fun (pname, source_captured) ->
                   F.fprintf fmt "@.DUPLICATE_SYMBOLS source: %a source_captured:%a pname:%a@."
                     SourceFile.pp source
                     SourceFile.pp source_captured
                     Typ.Procname.pp pname
                 );
             )
      );
      Cg.extend exe_env.cg cg

(** get the global call graph *)
let get_cg exe_env =
  exe_env.cg

let get_file_data exe_env pname =
  try
    Some (Typ.Procname.Hash.find exe_env.proc_map pname)
  with Not_found ->
    begin
      let source_file_opt =
        match AttributesTable.load_attributes ~cache:true pname with
        | None ->
            L.(debug Analysis Medium) "can't find tenv_cfg_object for %a@." Typ.Procname.pp pname;
            None
        | Some proc_attributes when Config.reactive_capture ->
            let get_captured_file {ProcAttributes.source_file_captured} = source_file_captured in
            OndemandCapture.try_capture proc_attributes |> Option.map ~f:get_captured_file
        | Some proc_attributes ->
            Some proc_attributes.ProcAttributes.source_file_captured in
      let get_file_data_for_source source_file =
        let source_dir = DB.source_dir_from_source_file source_file in
        let cg_fname = DB.source_dir_get_internal_file source_dir ".cg" in
        let file_data = create_file_data exe_env.file_map source_file cg_fname in
        Typ.Procname.Hash.replace exe_env.proc_map pname file_data;
        file_data in
      Option.map ~f:get_file_data_for_source source_file_opt
    end

(** return the source file associated to the procedure *)
let get_source exe_env pname =
  Option.map
    ~f:(fun file_data -> file_data.source)
    (get_file_data exe_env pname)

let file_data_to_tenv file_data =
  if is_none file_data.tenv
  then file_data.tenv <- Tenv.load_from_file file_data.tenv_file;
  file_data.tenv

let file_data_to_cfg file_data =
  if is_none file_data.cfg
  then file_data.cfg <- Cfg.load_cfg_from_file file_data.cfg_file;
  file_data.cfg

let java_global_tenv =
  lazy
    (match Tenv.load_from_file DB.global_tenv_fname with
     | None ->
         failwithf
           "Could not load the global tenv at path %s@."
           (DB.filename_to_string DB.global_tenv_fname)
     | Some tenv -> tenv)

(** return the type environment associated to the procedure *)
let get_tenv exe_env proc_name =
  match proc_name with
  | Typ.Procname.Java _ ->
      Lazy.force java_global_tenv
  | _ ->
      begin
        match get_file_data exe_env proc_name with
        | Some file_data -> (
            match file_data_to_tenv file_data with
            | Some tenv ->
                tenv
            | None ->
                failwithf "get_tenv: tenv not found for %a in file %s"
                  Typ.Procname.pp proc_name (DB.filename_to_string file_data.tenv_file)
          )
        | None ->
            failwithf "get_tenv: file_data not found for %a" Typ.Procname.pp proc_name
      end

(** return the cfg associated to the procedure *)
let get_cfg exe_env pname =
  match get_file_data exe_env pname with
  | None ->
      None
  | Some file_data ->
      file_data_to_cfg file_data

(** return the proc desc associated to the procedure *)
let get_proc_desc exe_env pname =
  match get_cfg exe_env pname with
  | Some cfg ->
      Cfg.find_proc_desc_from_name cfg pname
  | None ->
      None

(** Create an exe_env from a source dir *)
let from_cluster cluster =
  let exe_env = create () in
  add_cg exe_env cluster;
  exe_env

(** [iter_files f exe_env] applies [f] to the filename and tenv and cfg for each file in [exe_env] *)
let iter_files f exe_env =
  let do_file _ file_data seen_files_acc =
    let fname = file_data.source in
    if SourceFile.Set.mem fname seen_files_acc ||
       (* only files added with add_cg* functions *)
       not (SourceFile.Set.mem fname exe_env.source_files)
    then seen_files_acc
    else
      begin
        Option.iter ~f:(fun cfg -> f fname cfg) (file_data_to_cfg file_data);
        SourceFile.Set.add fname seen_files_acc
      end in
  ignore (Typ.Procname.Hash.fold do_file exe_env.proc_map SourceFile.Set.empty)