chrome/tools/profile_reset/jtl_parser.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_TOOLS_PROFILE_RESET_JTL_PARSER_H_
   6 #define CHROME_TOOLS_PROFILE_RESET_JTL_PARSER_H_
   7
   8 #include <string>
   9 #include <vector>
  10
  11 #include "base/basictypes.h"
  12 #include "base/memory/scoped_ptr.h"
  13 #include "base/values.h"
  14
  15 // Parses text-based JTL source code into a stream of operation names, arguments
  16 // and separator kinds.
  17 class JtlParser {
  18  public:
  19   // Creates a new parser to parse |compacted_source_code|, which should already
  20   // be stripped of all comments and whitespace (except inside string literals).
  21   // Use RemoveCommentsAndAllWhitespace() to manufacture these arguments, also
  22   // see its comments for a description of |newline_indices|.
  23   JtlParser(const std::string& compacted_source_code,
  24             const std::vector<size_t>& newline_indices);
  25   ~JtlParser();
  26
  27   // Removes comments from |verbose_text| and compacts it into whitespace-free
  28   // format (except inside string literals). Elements in |newline_indices| will
  29   // be monotonically increasing and will refer to positions in |compacted_text|
  30   // such that a new line has been removed before that position.
  31   // Example:
  32   //   verbose_text = "H e l l o // my\n"
  33   //                  " dear \n"
  34   //                  "\n"
  35   //                  "world\" ! \""
  36   //   compacted_text = "Hellodearworld\" ! \""
  37   //                     01234567890123...
  38   //   newline_indices = {5, 9, 9}
  39   // Returns true on success, false if there were unmatched quotes in a line, in
  40   // which case |error_line_number| will be set accordingly if it is non-NULL.
  41   static bool RemoveCommentsAndAllWhitespace(
  42       const std::string& verbose_text,
  43       std::string* compacted_text,
  44       std::vector<size_t>* newline_indices,
  45       size_t* error_line_number);
  46
  47   // Returns true if the entire input has been successfully consumed. Note that
  48   // even when this returns false, a subsequent call to ParseNextOperation()
  49   // might still fail if the next operation cannot be parsed.
  50   bool HasFinished();
  51
  52   // Fetches the |name| and the |argument_list| of the next operation, and also
  53   // whether or not it |ends_the_sentence|, i.e. it is followed by the
  54   // end-of-sentence separator.
  55   // Returns false if there is a parsing error, in which case the values for the
  56   // output parameters are undefined, and |this| parser shall no longer be used.
  57   bool ParseNextOperation(std::string* name,
  58                           base::ListValue* argument_list,
  59                           bool* ends_the_sentence);
  60
  61   // Returns the compacted source code that was passed in to the constructor.
  62   const std::string& compacted_source() const { return compacted_source_; }
  63
  64   // Returns at which line the character at position |compacted_index| in the
  65   // |compacted_source()| was originally located.
  66   size_t GetOriginalLineNumber(size_t compacted_index) const;
  67
  68   size_t GetLastLineNumber() const;
  69   std::string GetLastContext() const;
  70
  71  private:
  72   // Contains pre-compiled regular expressions and related state. Factored out
  73   // to avoid this header depending on RE2 headers.
  74   struct ParsingState;
  75
  76   std::string compacted_source_;
  77   std::vector<size_t> newline_indices_;
  78   scoped_ptr<ParsingState> state_;
  79
  80   DISALLOW_COPY_AND_ASSIGN(JtlParser);
  81 };
  82
  83 #endif  // CHROME_TOOLS_PROFILE_RESET_JTL_PARSER_H_