ceph/src/rocksdb/file/read_write_util.cc

   1 //  Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.
   2 //  This source code is licensed under both the GPLv2 (found in the
   3 //  COPYING file in the root directory) and Apache 2.0 License
   4 //  (found in the LICENSE.Apache file in the root directory).
   5 //
   6 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
   7 // Use of this source code is governed by a BSD-style license that can be
   8 // found in the LICENSE file. See the AUTHORS file for names of contributors.
   9
  10 #include "file/read_write_util.h"
  11
  12 #include <sstream>
  13 #include "test_util/sync_point.h"
  14
  15 namespace ROCKSDB_NAMESPACE {
  16
  17 IOStatus NewWritableFile(FileSystem* fs, const std::string& fname,
  18                          std::unique_ptr<FSWritableFile>* result,
  19                          const FileOptions& options) {
  20   IOStatus s = fs->NewWritableFile(fname, options, result, nullptr);
  21   TEST_KILL_RANDOM("NewWritableFile:0", rocksdb_kill_odds * REDUCE_ODDS2);
  22   return s;
  23 }
  24
  25 bool ReadOneLine(std::istringstream* iss, SequentialFileReader* seq_file_reader,
  26                  std::string* output, bool* has_data, Status* result) {
  27   const int kBufferSize = 8192;
  28   char buffer[kBufferSize + 1];
  29   Slice input_slice;
  30
  31   std::string line;
  32   bool has_complete_line = false;
  33   while (!has_complete_line) {
  34     if (std::getline(*iss, line)) {
  35       has_complete_line = !iss->eof();
  36     } else {
  37       has_complete_line = false;
  38     }
  39     if (!has_complete_line) {
  40       // if we're not sure whether we have a complete line,
  41       // further read from the file.
  42       if (*has_data) {
  43         *result = seq_file_reader->Read(kBufferSize, &input_slice, buffer);
  44       }
  45       if (input_slice.size() == 0) {
  46         // meaning we have read all the data
  47         *has_data = false;
  48         break;
  49       } else {
  50         iss->str(line + input_slice.ToString());
  51         // reset the internal state of iss so that we can keep reading it.
  52         iss->clear();
  53         *has_data = (input_slice.size() == kBufferSize);
  54         continue;
  55       }
  56     }
  57   }
  58   *output = line;
  59   return *has_data || has_complete_line;
  60 }
  61
  62 #ifndef NDEBUG
  63 bool IsFileSectorAligned(const size_t off, size_t sector_size) {
  64   return off % sector_size == 0;
  65 }
  66 #endif  // NDEBUG
  67 }  // namespace ROCKSDB_NAMESPACE