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
19namespace {
20
21// Size of the uint64 hash_key number in Hex format in a string.
22const size_t kEntryHashKeyAsHexStringSize = 2 * sizeof(uint64);
23
24// TODO(clamy, gavinp): this should go in base
25bool 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
47namespace disk_cache {
48
49namespace simple_util {
50
51std::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
57std::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
64bool 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
72uint64 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
82std::string GetFilenameFromEntryHashAndFileIndex(uint64 entry_hash,
83                                                 int file_index) {
84  return base::StringPrintf("%016" PRIx64 "_%1d", entry_hash, file_index);
85}
86
87std::string GetSparseFilenameFromEntryHash(uint64 entry_hash) {
88  return base::StringPrintf("%016" PRIx64 "_s", entry_hash);
89}
90
91std::string GetFilenameFromKeyAndFileIndex(const std::string& key,
92                                           int file_index) {
93  return GetEntryHashKeyAsHexString(key) +
94         base::StringPrintf("_%1d", file_index);
95}
96
97int32 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
104int64 GetFileSizeFromKeyAndDataSize(const std::string& key, int32 data_size) {
105  return data_size + key.size() + sizeof(SimpleFileHeader) +
106      sizeof(SimpleFileEOF);
107}
108
109int GetFileIndexFromStreamIndex(int stream_index) {
110  return (stream_index == 2) ? 1 : 0;
111}
112
113// TODO(clamy, gavinp): this should go in base
114bool 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