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
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
|
// 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.
#ifndef BASE_FILES_FILE_UTIL_PROXY_H_
#define BASE_FILES_FILE_UTIL_PROXY_H_
#include "base/base_export.h"
#include "base/callback_forward.h"
#include "base/files/file_path.h"
#include "base/memory/ref_counted.h"
#include "base/platform_file.h"
namespace tracked_objects {
class Location;
};
namespace base {
class TaskRunner;
class Time;
// This class provides asynchronous access to common file routines.
class BASE_EXPORT FileUtilProxy {
public:
// This callback is used by methods that report only an error code. It is
// valid to pass a null callback to any function that takes a StatusCallback,
// in which case the operation will complete silently.
typedef Callback<void(PlatformFileError)> StatusCallback;
typedef Callback<void(PlatformFileError,
PassPlatformFile,
bool /* created */)> CreateOrOpenCallback;
typedef Callback<void(PlatformFileError,
PassPlatformFile,
const FilePath&)> CreateTemporaryCallback;
typedef Callback<void(PlatformFileError,
const PlatformFileInfo&)> GetFileInfoCallback;
typedef Callback<void(PlatformFileError,
const char* /* data */,
int /* bytes read */)> ReadCallback;
typedef Callback<void(PlatformFileError,
int /* bytes written */)> WriteCallback;
typedef Callback<PlatformFileError(PlatformFile*, bool*)> CreateOrOpenTask;
typedef Callback<PlatformFileError(PlatformFile)> CloseTask;
typedef Callback<PlatformFileError(void)> FileTask;
// Creates or opens a file with the given flags. It is invalid to pass a null
// callback. If PLATFORM_FILE_CREATE is set in |file_flags| it always tries to
// create a new file at the given |file_path| and calls back with
// PLATFORM_FILE_ERROR_FILE_EXISTS if the |file_path| already exists.
//
// This returns false if task posting to |task_runner| has failed.
static bool CreateOrOpen(TaskRunner* task_runner,
const FilePath& file_path,
int file_flags,
const CreateOrOpenCallback& callback);
// Creates a temporary file for writing. The path and an open file handle are
// returned. It is invalid to pass a null callback. The additional file flags
// will be added on top of the default file flags which are:
// base::PLATFORM_FILE_CREATE_ALWAYS
// base::PLATFORM_FILE_WRITE
// base::PLATFORM_FILE_TEMPORARY.
// Set |additional_file_flags| to 0 for synchronous writes and set to
// base::PLATFORM_FILE_ASYNC to support asynchronous file operations.
//
// This returns false if task posting to |task_runner| has failed.
static bool CreateTemporary(
TaskRunner* task_runner,
int additional_file_flags,
const CreateTemporaryCallback& callback);
// Close the given file handle.
// This returns false if task posting to |task_runner| has failed.
static bool Close(TaskRunner* task_runner,
PlatformFile,
const StatusCallback& callback);
// Retrieves the information about a file. It is invalid to pass a null
// callback.
// This returns false if task posting to |task_runner| has failed.
static bool GetFileInfo(
TaskRunner* task_runner,
const FilePath& file_path,
const GetFileInfoCallback& callback);
// Does the same as GetFileInfo but takes PlatformFile instead of FilePath.
// This returns false if task posting to |task_runner| has failed.
static bool GetFileInfoFromPlatformFile(
TaskRunner* task_runner,
PlatformFile file,
const GetFileInfoCallback& callback);
// Deletes a file or a directory.
// It is an error to delete a non-empty directory with recursive=false.
// This returns false if task posting to |task_runner| has failed.
static bool DeleteFile(TaskRunner* task_runner,
const FilePath& file_path,
bool recursive,
const StatusCallback& callback);
// Reads from a file. On success, the file pointer is moved to position
// |offset + bytes_to_read| in the file. The callback can be null.
//
// This returns false if |bytes_to_read| is less than zero, or
// if task posting to |task_runner| has failed.
static bool Read(
TaskRunner* task_runner,
PlatformFile file,
int64 offset,
int bytes_to_read,
const ReadCallback& callback);
// Writes to a file. If |offset| is greater than the length of the file,
// |false| is returned. On success, the file pointer is moved to position
// |offset + bytes_to_write| in the file. The callback can be null.
// |bytes_to_write| must be greater than zero.
//
// This returns false if |bytes_to_write| is less than or equal to zero,
// if |buffer| is NULL, or if task posting to |task_runner| has failed.
static bool Write(
TaskRunner* task_runner,
PlatformFile file,
int64 offset,
const char* buffer,
int bytes_to_write,
const WriteCallback& callback);
// Touches a file. The callback can be null.
// This returns false if task posting to |task_runner| has failed.
static bool Touch(
TaskRunner* task_runner,
PlatformFile file,
const Time& last_access_time,
const Time& last_modified_time,
const StatusCallback& callback);
// Touches a file. The callback can be null.
// This returns false if task posting to |task_runner| has failed.
static bool Touch(
TaskRunner* task_runner,
const FilePath& file_path,
const Time& last_access_time,
const Time& last_modified_time,
const StatusCallback& callback);
// Truncates a file to the given length. If |length| is greater than the
// current length of the file, the file will be extended with zeroes.
// The callback can be null.
// This returns false if task posting to |task_runner| has failed.
static bool Truncate(
TaskRunner* task_runner,
PlatformFile file,
int64 length,
const StatusCallback& callback);
// Truncates a file to the given length. If |length| is greater than the
// current length of the file, the file will be extended with zeroes.
// The callback can be null.
// This returns false if task posting to |task_runner| has failed.
static bool Truncate(
TaskRunner* task_runner,
const FilePath& path,
int64 length,
const StatusCallback& callback);
// Flushes a file. The callback can be null.
// This returns false if task posting to |task_runner| has failed.
static bool Flush(
TaskRunner* task_runner,
PlatformFile file,
const StatusCallback& callback);
// Relay helpers.
// They return false if posting a given task to |task_runner| has failed.
static bool RelayCreateOrOpen(
TaskRunner* task_runner,
const CreateOrOpenTask& open_task,
const CloseTask& close_task,
const CreateOrOpenCallback& callback);
static bool RelayClose(
TaskRunner* task_runner,
const CloseTask& close_task,
PlatformFile,
const StatusCallback& callback);
private:
DISALLOW_IMPLICIT_CONSTRUCTORS(FileUtilProxy);
};
} // namespace base
#endif // BASE_FILES_FILE_UTIL_PROXY_H_
|
