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 #ifndef SEASTAR_MODULE
25 #include <seastar/core/file.hh>
26 #include <seastar/util/modules.hh>
27 #endif
28 
29 namespace seastar {
30 
33 
42 SEASTAR_MODULE_EXPORT
43 class layered_file_impl : public file_impl {
44 protected:
45  file _underlying_file;
46 public:
50  : _underlying_file(std::move(underlying_file)) {
51  _memory_dma_alignment = _underlying_file.memory_dma_alignment();
52  _disk_read_dma_alignment = _underlying_file.disk_read_dma_alignment();
53  _disk_write_dma_alignment = _underlying_file.disk_write_dma_alignment();
54  _disk_overwrite_dma_alignment = _underlying_file.disk_overwrite_dma_alignment();
55  }
56 
58  file& underlying_file() noexcept {
59  return _underlying_file;
60  }
61 
63  const file& underlying_file() const noexcept {
64  return _underlying_file;
65  }
66 };
67 
68 
70 
71 
72 }
Definition: file.hh:118
Definition: file.hh:194
uint64_t memory_dma_alignment() const noexcept
Alignment requirement for data buffers.
Definition: file.hh:265
uint64_t disk_read_dma_alignment() const noexcept
Alignment requirement for file offsets (for reads)
Definition: file.hh:245
uint64_t disk_overwrite_dma_alignment() const noexcept
Definition: file.hh:260
uint64_t disk_write_dma_alignment() const noexcept
Alignment requirement for file offsets (for writes)
Definition: file.hh:250
Definition: layered_file.hh:43
const file & underlying_file() const noexcept
The underlying file which can be used to back I/O methods.
Definition: layered_file.hh:63
layered_file_impl(file underlying_file) noexcept
Definition: layered_file.hh:49
file & underlying_file() noexcept
The underlying file which can be used to back I/O methods.
Definition: layered_file.hh:58
Seastar API namespace.
Definition: abort_on_ebadf.hh:26