ceph/src/seastar/tests/unit/mock_file.hh

   1 /*
   2  * This file is open source software, licensed to you under the terms
   3  * of the Apache License, Version 2.0 (the "License").  See the NOTICE file
   4  * distributed with this work for additional information regarding copyright
   5  * ownership.  You may not use this file except in compliance with the License.
   6  *
   7  * You may obtain a copy of the License at
   8  *
   9  *   http://www.apache.org/licenses/LICENSE-2.0
  10  *
  11  * Unless required by applicable law or agreed to in writing,
  12  * software distributed under the License is distributed on an
  13  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
  14  * KIND, either express or implied.  See the License for the
  15  * specific language governing permissions and limitations
  16  * under the License.
  17  */
  18 /*
  19  * Copyright (C) 2017 ScyllaDB Ltd.
  20  */
  21
  22 #pragma once
  23
  24 #include <boost/range/numeric.hpp>
  25
  26 #include <seastar/testing/seastar_test.hh>
  27 #include <seastar/core/file.hh>
  28
  29 namespace seastar {
  30
  31 class mock_read_only_file final : public file_impl {
  32     bool _closed = false;
  33     uint64_t _total_file_size;
  34     size_t _allowed_read_requests = 0;
  35     std::function<void(size_t)> _verify_length;
  36 private:
  37     size_t verify_read(uint64_t position, size_t length) {
  38         BOOST_CHECK(!_closed);
  39         BOOST_CHECK_LE(position, _total_file_size);
  40         BOOST_CHECK_LE(position + length, _total_file_size);
  41         if (position + length != _total_file_size) {
  42             _verify_length(length);
  43         }
  44         BOOST_CHECK(_allowed_read_requests);
  45         assert(_allowed_read_requests);
  46         _allowed_read_requests--;
  47         return length;
  48     }
  49 public:
  50     explicit mock_read_only_file(uint64_t file_size) noexcept
  51         : _total_file_size(file_size)
  52         , _verify_length([] (auto) { })
  53     { }
  54
  55     void set_read_size_verifier(std::function<void(size_t)> fn) {
  56         _verify_length = fn;
  57     }
  58     void set_expected_read_size(size_t expected) {
  59         _verify_length = [expected] (auto length) {
  60             BOOST_CHECK_EQUAL(length, expected);
  61         };
  62     }
  63     void set_allowed_read_requests(size_t requests) {
  64         _allowed_read_requests = requests;
  65     }
  66
  67     virtual future<size_t> write_dma(uint64_t, const void*, size_t, const io_priority_class&) override {
  68         throw std::bad_function_call();
  69     }
  70     virtual future<size_t> write_dma(uint64_t, std::vector<iovec>, const io_priority_class&) override {
  71         throw std::bad_function_call();
  72     }
  73     virtual future<size_t> read_dma(uint64_t pos, void*, size_t len, const io_priority_class&) override {
  74         return make_ready_future<size_t>(verify_read(pos, len));
  75     }
  76     virtual future<size_t> read_dma(uint64_t pos, std::vector<iovec> iov, const io_priority_class&) override {
  77         auto length = boost::accumulate(iov | boost::adaptors::transformed([] (auto&& iov) { return iov.iov_len; }),
  78                                         size_t(0), std::plus<size_t>());
  79         return make_ready_future<size_t>(verify_read(pos, length));
  80     }
  81     virtual future<> flush() override {
  82         return make_ready_future<>();
  83     }
  84     virtual future<struct stat> stat() override {
  85         throw std::bad_function_call();
  86     }
  87     virtual future<> truncate(uint64_t) {
  88         throw std::bad_function_call();
  89     }
  90     virtual future<> discard(uint64_t offset, uint64_t length) override {
  91         throw std::bad_function_call();
  92     }
  93     virtual future<> allocate(uint64_t position, uint64_t length) override {
  94         throw std::bad_function_call();
  95     }
  96     virtual future<uint64_t> size() override {
  97         return make_ready_future<uint64_t>(_total_file_size);
  98     }
  99     virtual future<> close() override {
 100         BOOST_CHECK(!_closed);
 101         _closed = true;
 102         return make_ready_future<>();
 103     }
 104     virtual subscription<directory_entry> list_directory(std::function<future<> (directory_entry de)>) override {
 105         throw std::bad_function_call();
 106     }
 107     virtual future<temporary_buffer<uint8_t>> dma_read_bulk(uint64_t offset, size_t range_size, const io_priority_class&) override {
 108         auto length = verify_read(offset, range_size);
 109         return make_ready_future<temporary_buffer<uint8_t>>(temporary_buffer<uint8_t>(length));
 110     }
 111 };
 112
 113 }