1 // Copyright (c) 2019-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 #include "env/composite_env_wrapper.h"
7 #include "rocksdb/file_system.h"
8 #include "options/db_options.h"
9 #include "rocksdb/utilities/object_registry.h"
10
11 namespace ROCKSDB_NAMESPACE {
12
FileSystem()13 FileSystem::FileSystem() {}
14
~FileSystem()15 FileSystem::~FileSystem() {}
16
Load(const std::string & value,std::shared_ptr<FileSystem> * result)17 Status FileSystem::Load(const std::string& value,
18 std::shared_ptr<FileSystem>* result) {
19 Status s;
20 #ifndef ROCKSDB_LITE
21 s = ObjectRegistry::NewInstance()->NewSharedObject<FileSystem>(value, result);
22 #else
23 (void)result;
24 s = Status::NotSupported("Cannot load FileSystem in LITE mode: ", value);
25 #endif
26 return s;
27 }
28
ReuseWritableFile(const std::string & fname,const std::string & old_fname,const FileOptions & opts,std::unique_ptr<FSWritableFile> * result,IODebugContext * dbg)29 IOStatus FileSystem::ReuseWritableFile(const std::string& fname,
30 const std::string& old_fname,
31 const FileOptions& opts,
32 std::unique_ptr<FSWritableFile>* result,
33 IODebugContext* dbg) {
34 IOStatus s = RenameFile(old_fname, fname, opts.io_options, dbg);
35 if (!s.ok()) {
36 return s;
37 }
38 return NewWritableFile(fname, opts, result, dbg);
39 }
40
OptimizeForLogRead(const FileOptions & file_options) const41 FileOptions FileSystem::OptimizeForLogRead(
42 const FileOptions& file_options) const {
43 FileOptions optimized_file_options(file_options);
44 optimized_file_options.use_direct_reads = false;
45 return optimized_file_options;
46 }
47
OptimizeForManifestRead(const FileOptions & file_options) const48 FileOptions FileSystem::OptimizeForManifestRead(
49 const FileOptions& file_options) const {
50 FileOptions optimized_file_options(file_options);
51 optimized_file_options.use_direct_reads = false;
52 return optimized_file_options;
53 }
54
OptimizeForLogWrite(const FileOptions & file_options,const DBOptions & db_options) const55 FileOptions FileSystem::OptimizeForLogWrite(const FileOptions& file_options,
56 const DBOptions& db_options) const {
57 FileOptions optimized_file_options(file_options);
58 optimized_file_options.bytes_per_sync = db_options.wal_bytes_per_sync;
59 optimized_file_options.writable_file_max_buffer_size =
60 db_options.writable_file_max_buffer_size;
61 return optimized_file_options;
62 }
63
OptimizeForManifestWrite(const FileOptions & file_options) const64 FileOptions FileSystem::OptimizeForManifestWrite(
65 const FileOptions& file_options) const {
66 return file_options;
67 }
68
OptimizeForCompactionTableWrite(const FileOptions & file_options,const ImmutableDBOptions & db_options) const69 FileOptions FileSystem::OptimizeForCompactionTableWrite(
70 const FileOptions& file_options,
71 const ImmutableDBOptions& db_options) const {
72 FileOptions optimized_file_options(file_options);
73 optimized_file_options.use_direct_writes =
74 db_options.use_direct_io_for_flush_and_compaction;
75 return optimized_file_options;
76 }
77
OptimizeForCompactionTableRead(const FileOptions & file_options,const ImmutableDBOptions & db_options) const78 FileOptions FileSystem::OptimizeForCompactionTableRead(
79 const FileOptions& file_options,
80 const ImmutableDBOptions& db_options) const {
81 FileOptions optimized_file_options(file_options);
82 optimized_file_options.use_direct_reads = db_options.use_direct_reads;
83 return optimized_file_options;
84 }
85
WriteStringToFile(FileSystem * fs,const Slice & data,const std::string & fname,bool should_sync)86 IOStatus WriteStringToFile(FileSystem* fs, const Slice& data,
87 const std::string& fname, bool should_sync) {
88 std::unique_ptr<FSWritableFile> file;
89 EnvOptions soptions;
90 IOStatus s = fs->NewWritableFile(fname, soptions, &file, nullptr);
91 if (!s.ok()) {
92 return s;
93 }
94 s = file->Append(data, IOOptions(), nullptr);
95 if (s.ok() && should_sync) {
96 s = file->Sync(IOOptions(), nullptr);
97 }
98 if (!s.ok()) {
99 fs->DeleteFile(fname, IOOptions(), nullptr);
100 }
101 return s;
102 }
103
ReadFileToString(FileSystem * fs,const std::string & fname,std::string * data)104 IOStatus ReadFileToString(FileSystem* fs, const std::string& fname,
105 std::string* data) {
106 FileOptions soptions;
107 data->clear();
108 std::unique_ptr<FSSequentialFile> file;
109 IOStatus s = status_to_io_status(
110 fs->NewSequentialFile(fname, soptions, &file, nullptr));
111 if (!s.ok()) {
112 return s;
113 }
114 static const int kBufferSize = 8192;
115 char* space = new char[kBufferSize];
116 while (true) {
117 Slice fragment;
118 s = file->Read(kBufferSize, IOOptions(), &fragment, space,
119 nullptr);
120 if (!s.ok()) {
121 break;
122 }
123 data->append(fragment.data(), fragment.size());
124 if (fragment.empty()) {
125 break;
126 }
127 }
128 delete[] space;
129 return s;
130 }
131
132 #ifdef OS_WIN
Default()133 std::shared_ptr<FileSystem> FileSystem::Default() {
134 static LegacyFileSystemWrapper default_fs(Env::Default());
135 static std::shared_ptr<LegacyFileSystemWrapper> default_fs_ptr(
136 &default_fs, [](LegacyFileSystemWrapper*) {});
137 return default_fs_ptr;
138 }
139 #endif
140
141 } // namespace ROCKSDB_NAMESPACE
142