1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
|
// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "webkit/blob/shareable_file_reference.h"
#include <map>
#include "base/file_util.h"
#include "base/files/file_util_proxy.h"
#include "base/lazy_instance.h"
#include "base/task_runner.h"
#include "base/threading/thread_checker.h"
namespace webkit_blob {
namespace {
// A shareable file map with enforcement of thread checker.
// This map may get deleted on a different thread in AtExitManager at the
// very end on the main thread (at the point all other threads must be
// terminated), so we use ThreadChecker rather than NonThreadSafe and do not
// check thread in the dtor.
class ShareableFileMap {
public:
typedef std::map<base::FilePath, ShareableFileReference*> FileMap;
typedef FileMap::iterator iterator;
typedef FileMap::key_type key_type;
typedef FileMap::value_type value_type;
ShareableFileMap() {}
iterator Find(key_type key) {
DCHECK(CalledOnValidThread());
return file_map_.find(key);
}
iterator End() {
DCHECK(CalledOnValidThread());
return file_map_.end();
}
std::pair<iterator, bool> Insert(value_type value) {
DCHECK(CalledOnValidThread());
return file_map_.insert(value);
}
void Erase(key_type key) {
DCHECK(CalledOnValidThread());
file_map_.erase(key);
}
bool CalledOnValidThread() const {
return thread_checker_.CalledOnValidThread();
}
private:
FileMap file_map_;
base::ThreadChecker thread_checker_;
DISALLOW_COPY_AND_ASSIGN(ShareableFileMap);
};
base::LazyInstance<ShareableFileMap> g_file_map = LAZY_INSTANCE_INITIALIZER;
} // namespace
// static
scoped_refptr<ShareableFileReference> ShareableFileReference::Get(
const base::FilePath& path) {
ShareableFileMap::iterator found = g_file_map.Get().Find(path);
ShareableFileReference* reference =
(found == g_file_map.Get().End()) ? NULL : found->second;
return scoped_refptr<ShareableFileReference>(reference);
}
// static
scoped_refptr<ShareableFileReference> ShareableFileReference::GetOrCreate(
const base::FilePath& path, FinalReleasePolicy policy,
base::TaskRunner* file_task_runner) {
DCHECK(file_task_runner);
typedef std::pair<ShareableFileMap::iterator, bool> InsertResult;
// Required for VS2010: http://connect.microsoft.com/VisualStudio/feedback/details/520043/error-converting-from-null-to-a-pointer-type-in-std-pair
webkit_blob::ShareableFileReference* null_reference = NULL;
InsertResult result = g_file_map.Get().Insert(
ShareableFileMap::value_type(path, null_reference));
if (result.second == false)
return scoped_refptr<ShareableFileReference>(result.first->second);
// Wasn't in the map, create a new reference and store the pointer.
scoped_refptr<ShareableFileReference> reference(
new ShareableFileReference(path, policy, file_task_runner));
result.first->second = reference.get();
return reference;
}
void ShareableFileReference::AddFinalReleaseCallback(
const FinalReleaseCallback& callback) {
DCHECK(g_file_map.Get().CalledOnValidThread());
final_release_callbacks_.push_back(callback);
}
ShareableFileReference::ShareableFileReference(
const base::FilePath& path, FinalReleasePolicy policy,
base::TaskRunner* file_task_runner)
: path_(path),
final_release_policy_(policy),
file_task_runner_(file_task_runner) {
DCHECK(g_file_map.Get().Find(path_)->second == NULL);
}
ShareableFileReference::~ShareableFileReference() {
DCHECK(g_file_map.Get().Find(path_)->second == this);
g_file_map.Get().Erase(path_);
for (size_t i = 0; i < final_release_callbacks_.size(); i++)
final_release_callbacks_[i].Run(path_);
if (final_release_policy_ == DELETE_ON_FINAL_RELEASE) {
base::FileUtilProxy::Delete(file_task_runner_, path_, false /* recursive */,
base::FileUtilProxy::StatusCallback());
}
}
} // namespace webkit_blob
|
