1/*
2 * Copyright (C) 2015 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
14 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
15 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
17 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
18 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
19 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
20 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
21 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
22 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
23 * THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#include "config.h"
27#include "NetworkCacheBlobStorage.h"
28
29#include "Logging.h"
30#include "NetworkCacheFileSystem.h"
31#include <fcntl.h>
32#include <wtf/FileSystem.h>
33#include <wtf/RunLoop.h>
34#include <wtf/SHA1.h>
35
36#if !OS(WINDOWS)
37#include <sys/mman.h>
38#include <sys/stat.h>
39#include <unistd.h>
40#endif
41
42namespace WebKit {
43namespace NetworkCache {
44
45BlobStorage::BlobStorage(const String& blobDirectoryPath, Salt salt)
46 : m_blobDirectoryPath(blobDirectoryPath)
47 , m_salt(salt)
48{
49}
50
51String BlobStorage::blobDirectoryPath() const
52{
53 return m_blobDirectoryPath.isolatedCopy();
54}
55
56void BlobStorage::synchronize()
57{
58 ASSERT(!RunLoop::isMain());
59
60 FileSystem::makeAllDirectories(blobDirectoryPath());
61
62 m_approximateSize = 0;
63 auto blobDirectory = blobDirectoryPath();
64 traverseDirectory(blobDirectory, [this, &blobDirectory](const String& name, DirectoryEntryType type) {
65 if (type != DirectoryEntryType::File)
66 return;
67 auto path = FileSystem::pathByAppendingComponent(blobDirectory, name);
68 auto filePath = FileSystem::fileSystemRepresentation(path);
69 struct stat stat;
70 ::stat(filePath.data(), &stat);
71 // No clients left for this blob.
72 if (stat.st_nlink == 1)
73 unlink(filePath.data());
74 else
75 m_approximateSize += stat.st_size;
76 });
77
78 LOG(NetworkCacheStorage, "(NetworkProcess) blob synchronization completed approximateSize=%zu", approximateSize());
79}
80
81String BlobStorage::blobPathForHash(const SHA1::Digest& hash) const
82{
83 auto hashAsString = SHA1::hexDigest(hash);
84 return FileSystem::pathByAppendingComponent(blobDirectoryPath(), String::fromUTF8(hashAsString));
85}
86
87BlobStorage::Blob BlobStorage::add(const String& path, const Data& data)
88{
89 ASSERT(!RunLoop::isMain());
90
91 auto hash = computeSHA1(data, m_salt);
92 if (data.isEmpty())
93 return { data, hash };
94
95 String blobPath = blobPathForHash(hash);
96
97 FileSystem::deleteFile(path);
98
99 bool blobExists = FileSystem::fileExists(blobPath);
100 if (blobExists) {
101 FileSystem::makeSafeToUseMemoryMapForPath(blobPath);
102 auto existingData = mapFile(blobPath);
103 if (bytesEqual(existingData, data)) {
104 if (!FileSystem::hardLink(blobPath, path))
105 WTFLogAlways("Failed to create hard link from %s to %s", blobPath.utf8().data(), path.utf8().data());
106 return { existingData, hash };
107 }
108 FileSystem::deleteFile(blobPath);
109 }
110
111 auto mappedData = data.mapToFile(blobPath);
112 if (mappedData.isNull())
113 return { };
114
115 FileSystem::makeSafeToUseMemoryMapForPath(blobPath);
116
117 if (!FileSystem::hardLink(blobPath, path))
118 WTFLogAlways("Failed to create hard link from %s to %s", blobPath.utf8().data(), path.utf8().data());
119
120 m_approximateSize += mappedData.size();
121
122 return { mappedData, hash };
123}
124
125BlobStorage::Blob BlobStorage::get(const String& path)
126{
127 ASSERT(!RunLoop::isMain());
128
129 auto linkPath = FileSystem::fileSystemRepresentation(path);
130 auto data = mapFile(linkPath.data());
131
132 return { data, computeSHA1(data, m_salt) };
133}
134
135void BlobStorage::remove(const String& path)
136{
137 ASSERT(!RunLoop::isMain());
138
139 FileSystem::deleteFile(path);
140}
141
142unsigned BlobStorage::shareCount(const String& path)
143{
144 ASSERT(!RunLoop::isMain());
145
146 auto linkPath = FileSystem::fileSystemRepresentation(path);
147 struct stat stat;
148 if (::stat(linkPath.data(), &stat) < 0)
149 return 0;
150 // Link count is 2 in the single client case (the blob file and a link).
151 return stat.st_nlink - 1;
152}
153
154}
155}
156