1// Copyright (c) 2012 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#ifndef NET_BASE_DIRECTORY_LISTER_H_
6#define NET_BASE_DIRECTORY_LISTER_H_
7
8#include <vector>
9
10#include "base/files/file_enumerator.h"
11#include "base/files/file_path.h"
12#include "base/memory/ref_counted.h"
13#include "base/message_loop/message_loop_proxy.h"
14#include "net/base/net_export.h"
15
16namespace net {
17
18//
19// This class provides an API for listing the contents of a directory on the
20// filesystem asynchronously.  It spawns a background thread, and enumerates
21// the specified directory on that thread.  It marshalls WIN32_FIND_DATA
22// structs over to the main application thread.  The consumer of this class
23// is insulated from any of the multi-threading details.
24//
25class NET_EXPORT DirectoryLister  {
26 public:
27  // Represents one file found.
28  struct DirectoryListerData {
29    base::FileEnumerator::FileInfo info;
30    base::FilePath path;
31  };
32
33  // Implement this class to receive directory entries.
34  class DirectoryListerDelegate {
35   public:
36    // Called for each file found by the lister.
37    virtual void OnListFile(const DirectoryListerData& data) = 0;
38
39    // Called when the listing is complete.
40    virtual void OnListDone(int error) = 0;
41
42   protected:
43    virtual ~DirectoryListerDelegate() {}
44  };
45
46  // Sort options
47  // ALPHA_DIRS_FIRST is the default sort :
48  //   directories first in name order, then files by name order
49  // FULL_PATH sorts by paths as strings, ignoring files v. directories
50  // DATE sorts by last modified date
51  enum SortType {
52    NO_SORT,
53    DATE,
54    ALPHA_DIRS_FIRST,
55    FULL_PATH
56  };
57
58  DirectoryLister(const base::FilePath& dir,
59                  DirectoryListerDelegate* delegate);
60
61  DirectoryLister(const base::FilePath& dir,
62                  bool recursive,
63                  SortType sort,
64                  DirectoryListerDelegate* delegate);
65
66  // Will invoke Cancel().
67  ~DirectoryLister();
68
69  // Call this method to start the directory enumeration thread.
70  bool Start();
71
72  // Call this method to asynchronously stop directory enumeration.  The
73  // delegate will not be called back.
74  void Cancel();
75
76 private:
77  class Core : public base::RefCountedThreadSafe<Core> {
78   public:
79    Core(const base::FilePath& dir,
80         bool recursive,
81         SortType sort,
82         DirectoryLister* lister);
83
84    bool Start();
85
86    void Cancel();
87
88   private:
89    friend class base::RefCountedThreadSafe<Core>;
90    class DataEvent;
91
92    ~Core();
93
94    // This method runs on a WorkerPool thread.
95    void StartInternal();
96
97    void SendData(const std::vector<DirectoryListerData>& data);
98
99    void OnDone(int error);
100
101    base::FilePath dir_;
102    bool recursive_;
103    SortType sort_;
104    scoped_refptr<base::MessageLoopProxy> origin_loop_;
105
106    // |lister_| gets set to NULL when canceled.
107    DirectoryLister* lister_;
108
109    DISALLOW_COPY_AND_ASSIGN(Core);
110  };
111
112  void OnReceivedData(const DirectoryListerData& data);
113  void OnDone(int error);
114
115  const scoped_refptr<Core> core_;
116  DirectoryListerDelegate* const delegate_;
117
118  DISALLOW_COPY_AND_ASSIGN(DirectoryLister);
119};
120
121}  // namespace net
122
123#endif  // NET_BASE_DIRECTORY_LISTER_H_
124