chrome/browser/profile_resetter/jtl_interpreter.h

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CHROME_BROWSER_PROFILE_RESETTER_JTL_INTERPRETER_H_
   6 #define CHROME_BROWSER_PROFILE_RESETTER_JTL_INTERPRETER_H_
   7
   8 #include <string>
   9
  10 #include "base/basictypes.h"
  11 #include "base/values.h"
  12
  13 // Executes a JTL program on a given dictionary.
  14 //
  15 // JTL (Json Traversal Language) programs are defined in jtl_foundation.h
  16 class JtlInterpreter {
  17  public:
  18   enum Result {
  19     OK,
  20     PARSE_ERROR,
  21     RUNTIME_ERROR,
  22     RESULT_MAX,
  23   };
  24
  25   // |hasher_seed| is a value used in jtl_foundation::Hasher. All node names,
  26   // strings, integers and doubles are hashed before being compared to hash
  27   // values listed in |program|.
  28   // |program| is a byte array containing a JTL program.
  29   // |input| is a dictionary on which the program is evaluated.
  30   JtlInterpreter(const std::string& hasher_seed,
  31                  const std::string& program,
  32                  const base::DictionaryValue* input);
  33   ~JtlInterpreter();
  34
  35   void Execute();
  36
  37   Result result() const { return result_; }
  38   const base::DictionaryValue* working_memory() const {
  39     return working_memory_.get();
  40   }
  41   bool GetOutputBoolean(const std::string& unhashed_key, bool* output) const;
  42   bool GetOutputString(const std::string& unhashed_key,
  43                        std::string* output) const;
  44
  45   // Generates a checksum of the loaded program, defined as the first 3 bytes of
  46   // the program's SHA-256 hash interpreted as a big-endian integer.
  47   int CalculateProgramChecksum() const;
  48
  49  private:
  50   // Input.
  51   std::string hasher_seed_;
  52   std::string program_;
  53   const base::DictionaryValue* input_;
  54   // Output.
  55   scoped_ptr<base::DictionaryValue> working_memory_;
  56   Result result_;
  57
  58   DISALLOW_COPY_AND_ASSIGN(JtlInterpreter);
  59 };
  60
  61 #endif  // CHROME_BROWSER_PROFILE_RESETTER_JTL_INTERPRETER_H_