1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
|
// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
#pragma once
#include <cinttypes>
#include <memory>
#include "db/blob/blob_read_request.h"
#include "file/random_access_file_reader.h"
#include "rocksdb/compression_type.h"
#include "rocksdb/rocksdb_namespace.h"
#include "util/autovector.h"
namespace ROCKSDB_NAMESPACE {
class Status;
struct ImmutableOptions;
struct FileOptions;
class HistogramImpl;
struct ReadOptions;
class Slice;
class FilePrefetchBuffer;
class BlobContents;
class Statistics;
class BlobFileReader {
public:
static Status Create(const ImmutableOptions& immutable_options,
const FileOptions& file_options,
uint32_t column_family_id,
HistogramImpl* blob_file_read_hist,
uint64_t blob_file_number,
const std::shared_ptr<IOTracer>& io_tracer,
std::unique_ptr<BlobFileReader>* reader);
BlobFileReader(const BlobFileReader&) = delete;
BlobFileReader& operator=(const BlobFileReader&) = delete;
~BlobFileReader();
Status GetBlob(const ReadOptions& read_options, const Slice& user_key,
uint64_t offset, uint64_t value_size,
CompressionType compression_type,
FilePrefetchBuffer* prefetch_buffer,
MemoryAllocator* allocator,
std::unique_ptr<BlobContents>* result,
uint64_t* bytes_read) const;
// offsets must be sorted in ascending order by caller.
void MultiGetBlob(
const ReadOptions& read_options, MemoryAllocator* allocator,
autovector<std::pair<BlobReadRequest*, std::unique_ptr<BlobContents>>>&
blob_reqs,
uint64_t* bytes_read) const;
CompressionType GetCompressionType() const { return compression_type_; }
uint64_t GetFileSize() const { return file_size_; }
private:
BlobFileReader(std::unique_ptr<RandomAccessFileReader>&& file_reader,
uint64_t file_size, CompressionType compression_type,
SystemClock* clock, Statistics* statistics);
static Status OpenFile(const ImmutableOptions& immutable_options,
const FileOptions& file_opts,
HistogramImpl* blob_file_read_hist,
uint64_t blob_file_number,
const std::shared_ptr<IOTracer>& io_tracer,
uint64_t* file_size,
std::unique_ptr<RandomAccessFileReader>* file_reader);
static Status ReadHeader(const RandomAccessFileReader* file_reader,
uint32_t column_family_id, Statistics* statistics,
CompressionType* compression_type);
static Status ReadFooter(const RandomAccessFileReader* file_reader,
uint64_t file_size, Statistics* statistics);
using Buffer = std::unique_ptr<char[]>;
static Status ReadFromFile(const RandomAccessFileReader* file_reader,
uint64_t read_offset, size_t read_size,
Statistics* statistics, Slice* slice, Buffer* buf,
AlignedBuf* aligned_buf,
Env::IOPriority rate_limiter_priority);
static Status VerifyBlob(const Slice& record_slice, const Slice& user_key,
uint64_t value_size);
static Status UncompressBlobIfNeeded(const Slice& value_slice,
CompressionType compression_type,
MemoryAllocator* allocator,
SystemClock* clock,
Statistics* statistics,
std::unique_ptr<BlobContents>* result);
std::unique_ptr<RandomAccessFileReader> file_reader_;
uint64_t file_size_;
CompressionType compression_type_;
SystemClock* clock_;
Statistics* statistics_;
};
} // namespace ROCKSDB_NAMESPACE
|
