Seastar
High performance C++ framework for concurrent servers
layered_file.hh
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18 /*
19  * Copyright 2020 ScyllaDB
20  */
21 
22 #pragma once
23 
24 #include <seastar/core/file.hh>
25 
26 namespace seastar {
27 
30 
39 class layered_file_impl : public file_impl {
40 protected:
41  file _underlying_file;
42 public:
46  : _underlying_file(std::move(underlying_file)) {
47  _memory_dma_alignment = _underlying_file.memory_dma_alignment();
48  _disk_read_dma_alignment = _underlying_file.disk_read_dma_alignment();
49  _disk_write_dma_alignment = _underlying_file.disk_write_dma_alignment();
50  _disk_overwrite_dma_alignment = _underlying_file.disk_overwrite_dma_alignment();
51  }
52 
54  file& underlying_file() noexcept {
55  return _underlying_file;
56  }
57 
59  const file& underlying_file() const noexcept {
60  return _underlying_file;
61  }
62 };
63 
64 
66 
67 
68 }
Definition: file.hh:101
Definition: file.hh:166
uint64_t memory_dma_alignment() const noexcept
Alignment requirement for data buffers.
Definition: file.hh:237
uint64_t disk_read_dma_alignment() const noexcept
Alignment requirement for file offsets (for reads)
Definition: file.hh:217
uint64_t disk_overwrite_dma_alignment() const noexcept
Definition: file.hh:232
uint64_t disk_write_dma_alignment() const noexcept
Alignment requirement for file offsets (for writes)
Definition: file.hh:222
Definition: layered_file.hh:39
const file & underlying_file() const noexcept
The underlying file which can be used to back I/O methods.
Definition: layered_file.hh:59
layered_file_impl(file underlying_file) noexcept
Definition: layered_file.hh:45
file & underlying_file() noexcept
The underlying file which can be used to back I/O methods.
Definition: layered_file.hh:54
Seastar API namespace.
Definition: abort_on_ebadf.hh:24