1 // Copyright (c) 2011-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 "file/file_util.h"
7
8 #include <string>
9 #include <algorithm>
10
11 #include "file/random_access_file_reader.h"
12 #include "file/sequence_file_reader.h"
13 #include "file/sst_file_manager_impl.h"
14 #include "file/writable_file_writer.h"
15 #include "rocksdb/env.h"
16
17 namespace ROCKSDB_NAMESPACE {
18
19 // Utility function to copy a file up to a specified length
CopyFile(FileSystem * fs,const std::string & source,const std::string & destination,uint64_t size,bool use_fsync)20 Status CopyFile(FileSystem* fs, const std::string& source,
21 const std::string& destination, uint64_t size, bool use_fsync) {
22 const FileOptions soptions;
23 Status s;
24 std::unique_ptr<SequentialFileReader> src_reader;
25 std::unique_ptr<WritableFileWriter> dest_writer;
26
27 {
28 std::unique_ptr<FSSequentialFile> srcfile;
29 s = fs->NewSequentialFile(source, soptions, &srcfile, nullptr);
30 if (!s.ok()) {
31 return s;
32 }
33 std::unique_ptr<FSWritableFile> destfile;
34 s = fs->NewWritableFile(destination, soptions, &destfile, nullptr);
35 if (!s.ok()) {
36 return s;
37 }
38
39 if (size == 0) {
40 // default argument means copy everything
41 s = fs->GetFileSize(source, IOOptions(), &size, nullptr);
42 if (!s.ok()) {
43 return s;
44 }
45 }
46 src_reader.reset(new SequentialFileReader(std::move(srcfile), source));
47 dest_writer.reset(
48 new WritableFileWriter(std::move(destfile), destination, soptions));
49 }
50
51 char buffer[4096];
52 Slice slice;
53 while (size > 0) {
54 size_t bytes_to_read = std::min(sizeof(buffer), static_cast<size_t>(size));
55 s = src_reader->Read(bytes_to_read, &slice, buffer);
56 if (!s.ok()) {
57 return s;
58 }
59 if (slice.size() == 0) {
60 return Status::Corruption("file too small");
61 }
62 s = dest_writer->Append(slice);
63 if (!s.ok()) {
64 return s;
65 }
66 size -= slice.size();
67 }
68 return dest_writer->Sync(use_fsync);
69 }
70
71 // Utility function to create a file with the provided contents
CreateFile(FileSystem * fs,const std::string & destination,const std::string & contents,bool use_fsync)72 Status CreateFile(FileSystem* fs, const std::string& destination,
73 const std::string& contents, bool use_fsync) {
74 const EnvOptions soptions;
75 Status s;
76 std::unique_ptr<WritableFileWriter> dest_writer;
77
78 std::unique_ptr<FSWritableFile> destfile;
79 s = fs->NewWritableFile(destination, soptions, &destfile, nullptr);
80 if (!s.ok()) {
81 return s;
82 }
83 dest_writer.reset(
84 new WritableFileWriter(std::move(destfile), destination, soptions));
85 s = dest_writer->Append(Slice(contents));
86 if (!s.ok()) {
87 return s;
88 }
89 return dest_writer->Sync(use_fsync);
90 }
91
DeleteDBFile(const ImmutableDBOptions * db_options,const std::string & fname,const std::string & dir_to_sync,const bool force_bg,const bool force_fg)92 Status DeleteDBFile(const ImmutableDBOptions* db_options,
93 const std::string& fname, const std::string& dir_to_sync,
94 const bool force_bg, const bool force_fg) {
95 #ifndef ROCKSDB_LITE
96 SstFileManagerImpl* sfm =
97 static_cast<SstFileManagerImpl*>(db_options->sst_file_manager.get());
98 if (sfm && !force_fg) {
99 return sfm->ScheduleFileDeletion(fname, dir_to_sync, force_bg);
100 } else {
101 return db_options->env->DeleteFile(fname);
102 }
103 #else
104 (void)dir_to_sync;
105 (void)force_bg;
106 (void)force_fg;
107 // SstFileManager is not supported in ROCKSDB_LITE
108 // Delete file immediately
109 return db_options->env->DeleteFile(fname);
110 #endif
111 }
112
IsWalDirSameAsDBPath(const ImmutableDBOptions * db_options)113 bool IsWalDirSameAsDBPath(const ImmutableDBOptions* db_options) {
114 bool same = false;
115 assert(!db_options->db_paths.empty());
116 Status s = db_options->env->AreFilesSame(db_options->wal_dir,
117 db_options->db_paths[0].path, &same);
118 if (s.IsNotSupported()) {
119 same = db_options->wal_dir == db_options->db_paths[0].path;
120 }
121 return same;
122 }
123
124 } // namespace ROCKSDB_NAMESPACE
125