third_party/android_crazy_linker/src/src/crazy_linker_line_reader.h

   1 // Copyright 2014 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 CRAZY_LINKER_LINE_READER_H
   6 #define CRAZY_LINKER_LINE_READER_H
   7
   8 #include <string.h>
   9
  10 #include "crazy_linker_system.h"
  11
  12 namespace crazy {
  13
  14 // A class used to read text files line-by-line.
  15 // Usage:
  16 //    LineReader reader("/path/to/file");
  17 //    while (reader.GetNextLine()) {
  18 //       const char* line = reader.line();
  19 //       size_t line_len = reader.length();
  20 //       ... line is not necessarily zero-terminated.
  21 //    }
  22
  23 class LineReader {
  24  public:
  25   LineReader();
  26   explicit LineReader(const char* path);
  27   ~LineReader();
  28
  29   // Open a new file for testing. Doesn't fail. If there was an error
  30   // opening the file, GetNextLine() will simply return false.
  31   void Open(const char* file_path);
  32
  33   // Grab next line. Returns true on success, or false otherwise.
  34   bool GetNextLine();
  35
  36   // Return the start of the current line, this is _not_ zero-terminated
  37   // and always contains a final newline (\n).
  38   // Only call this after a successful GetNextLine().
  39   const char* line() const;
  40
  41   // Return the line length, this includes the final \n.
  42   // Only call this after a successful GetNextLine().
  43   size_t length() const;
  44
  45  private:
  46   void Reset(bool eof);
  47
  48   FileDescriptor fd_;
  49   bool eof_;
  50   size_t line_start_;
  51   size_t line_len_;
  52   size_t buff_size_;
  53   size_t buff_capacity_;
  54   char* buff_;
  55 };
  56
  57 }  // namespace crazy
  58
  59 #endif  // CRAZY_LINKER_LINE_READER_H