1 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "net/disk_cache/simple/simple_util.h"
6
7 #include <limits>
8
9 #include "base/files/file_util.h"
10 #include "base/format_macros.h"
11 #include "base/logging.h"
12 #include "base/sha1.h"
13 #include "base/strings/string_number_conversions.h"
14 #include "base/strings/stringprintf.h"
15 #include "base/threading/thread_restrictions.h"
16 #include "base/time/time.h"
17 #include "net/disk_cache/simple/simple_entry_format.h"
18
19 namespace {
20
21 // Size of the uint64 hash_key number in Hex format in a string.
22 const size_t kEntryHashKeyAsHexStringSize = 2 * sizeof(uint64);
23
24 // TODO(clamy, gavinp): this should go in base
GetNanoSecsFromStat(const struct stat & st,time_t * out_sec,long * out_nsec)25 bool GetNanoSecsFromStat(const struct stat& st,
26 time_t* out_sec,
27 long* out_nsec) {
28 #if defined(OS_ANDROID)
29 *out_sec = st.st_mtime;
30 *out_nsec = st.st_mtime_nsec;
31 return true;
32 #elif defined(OS_LINUX)
33 *out_sec = st.st_mtim.tv_sec;
34 *out_nsec = st.st_mtim.tv_nsec;
35 return true;
36 #elif defined(OS_MACOSX) || defined(OS_IOS) || defined(OS_BSD)
37 *out_sec = st.st_mtimespec.tv_sec;
38 *out_nsec = st.st_mtimespec.tv_nsec;
39 return true;
40 #else
41 return false;
42 #endif
43 }
44
45 } // namespace
46
47 namespace disk_cache {
48
49 namespace simple_util {
50
ConvertEntryHashKeyToHexString(uint64 hash_key)51 std::string ConvertEntryHashKeyToHexString(uint64 hash_key) {
52 const std::string hash_key_str = base::StringPrintf("%016" PRIx64, hash_key);
53 DCHECK_EQ(kEntryHashKeyAsHexStringSize, hash_key_str.size());
54 return hash_key_str;
55 }
56
GetEntryHashKeyAsHexString(const std::string & key)57 std::string GetEntryHashKeyAsHexString(const std::string& key) {
58 std::string hash_key_str =
59 ConvertEntryHashKeyToHexString(GetEntryHashKey(key));
60 DCHECK_EQ(kEntryHashKeyAsHexStringSize, hash_key_str.size());
61 return hash_key_str;
62 }
63
GetEntryHashKeyFromHexString(const base::StringPiece & hash_key,uint64 * hash_key_out)64 bool GetEntryHashKeyFromHexString(const base::StringPiece& hash_key,
65 uint64* hash_key_out) {
66 if (hash_key.size() != kEntryHashKeyAsHexStringSize) {
67 return false;
68 }
69 return base::HexStringToUInt64(hash_key, hash_key_out);
70 }
71
GetEntryHashKey(const std::string & key)72 uint64 GetEntryHashKey(const std::string& key) {
73 union {
74 unsigned char sha_hash[base::kSHA1Length];
75 uint64 key_hash;
76 } u;
77 base::SHA1HashBytes(reinterpret_cast<const unsigned char*>(key.data()),
78 key.size(), u.sha_hash);
79 return u.key_hash;
80 }
81
GetFilenameFromEntryHashAndFileIndex(uint64 entry_hash,int file_index)82 std::string GetFilenameFromEntryHashAndFileIndex(uint64 entry_hash,
83 int file_index) {
84 return base::StringPrintf("%016" PRIx64 "_%1d", entry_hash, file_index);
85 }
86
GetSparseFilenameFromEntryHash(uint64 entry_hash)87 std::string GetSparseFilenameFromEntryHash(uint64 entry_hash) {
88 return base::StringPrintf("%016" PRIx64 "_s", entry_hash);
89 }
90
GetFilenameFromKeyAndFileIndex(const std::string & key,int file_index)91 std::string GetFilenameFromKeyAndFileIndex(const std::string& key,
92 int file_index) {
93 return GetEntryHashKeyAsHexString(key) +
94 base::StringPrintf("_%1d", file_index);
95 }
96
GetDataSizeFromKeyAndFileSize(const std::string & key,int64 file_size)97 int32 GetDataSizeFromKeyAndFileSize(const std::string& key, int64 file_size) {
98 int64 data_size = file_size - key.size() - sizeof(SimpleFileHeader) -
99 sizeof(SimpleFileEOF);
100 DCHECK_GE(implicit_cast<int64>(std::numeric_limits<int32>::max()), data_size);
101 return data_size;
102 }
103
GetFileSizeFromKeyAndDataSize(const std::string & key,int32 data_size)104 int64 GetFileSizeFromKeyAndDataSize(const std::string& key, int32 data_size) {
105 return data_size + key.size() + sizeof(SimpleFileHeader) +
106 sizeof(SimpleFileEOF);
107 }
108
GetFileIndexFromStreamIndex(int stream_index)109 int GetFileIndexFromStreamIndex(int stream_index) {
110 return (stream_index == 2) ? 1 : 0;
111 }
112
113 // TODO(clamy, gavinp): this should go in base
GetMTime(const base::FilePath & path,base::Time * out_mtime)114 bool GetMTime(const base::FilePath& path, base::Time* out_mtime) {
115 DCHECK(out_mtime);
116 #if defined(OS_POSIX)
117 base::ThreadRestrictions::AssertIOAllowed();
118 struct stat file_stat;
119 if (stat(path.value().c_str(), &file_stat) != 0)
120 return false;
121 time_t sec;
122 long nsec;
123 if (GetNanoSecsFromStat(file_stat, &sec, &nsec)) {
124 int64 usec = (nsec / base::Time::kNanosecondsPerMicrosecond);
125 *out_mtime = base::Time::FromTimeT(sec)
126 + base::TimeDelta::FromMicroseconds(usec);
127 return true;
128 }
129 #endif
130 base::File::Info file_info;
131 if (!base::GetFileInfo(path, &file_info))
132 return false;
133 *out_mtime = file_info.last_modified;
134 return true;
135 }
136
137 } // namespace simple_backend
138
139 } // namespace disk_cache
140