Revert of Add button to add new FSP services to Files app. (patchset #8 id:140001...
[chromium-blink-merge.git] / chrome / browser / chromeos / drive / resource_metadata_storage.h
blobd2b7a18de8c3c9911b6e613a46b4279cf8e6b011
1 // Copyright 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.
5 #ifndef CHROME_BROWSER_CHROMEOS_DRIVE_RESOURCE_METADATA_STORAGE_H_
6 #define CHROME_BROWSER_CHROMEOS_DRIVE_RESOURCE_METADATA_STORAGE_H_
8 #include <string>
9 #include <vector>
11 #include "base/basictypes.h"
12 #include "base/files/file_path.h"
13 #include "base/memory/ref_counted.h"
14 #include "base/memory/scoped_ptr.h"
15 #include "chrome/browser/chromeos/drive/drive.pb.h"
16 #include "chrome/browser/chromeos/drive/file_errors.h"
18 namespace base {
19 class SequencedTaskRunner;
22 namespace leveldb {
23 class DB;
24 class Iterator;
27 namespace drive {
29 class ResourceEntry;
30 class ResourceMetadataHeader;
32 namespace internal {
34 // Storage for ResourceMetadata which is responsible to manage resource
35 // entries and child-parent relationships between entries.
36 class ResourceMetadataStorage {
37 public:
38 // This should be incremented when incompatibility change is made to DB
39 // format.
40 static const int kDBVersion = 13;
42 // Object to iterate over entries stored in this storage.
43 class Iterator {
44 public:
45 explicit Iterator(scoped_ptr<leveldb::Iterator> it);
46 ~Iterator();
48 // Returns true if this iterator cannot advance any more and does not point
49 // to a valid entry. Get() and Advance() should not be called in such cases.
50 bool IsAtEnd() const;
52 // Returns the ID of the entry currently pointed by this object.
53 std::string GetID() const;
55 // Returns the entry currently pointed by this object.
56 const ResourceEntry& GetValue() const;
58 // Advances to the next entry.
59 void Advance();
61 // Returns true if this object has encountered any error.
62 bool HasError() const;
64 private:
65 ResourceEntry entry_;
66 scoped_ptr<leveldb::Iterator> it_;
68 DISALLOW_COPY_AND_ASSIGN(Iterator);
71 // Cache information recovered from trashed DB.
72 struct RecoveredCacheInfo {
73 RecoveredCacheInfo();
74 ~RecoveredCacheInfo();
76 bool is_dirty;
77 std::string md5;
78 std::string title;
80 typedef std::map<std::string, RecoveredCacheInfo> RecoveredCacheInfoMap;
82 // Returns true if the DB was successfully upgraded to the newest version.
83 static bool UpgradeOldDB(const base::FilePath& directory_path);
85 ResourceMetadataStorage(const base::FilePath& directory_path,
86 base::SequencedTaskRunner* blocking_task_runner);
88 const base::FilePath& directory_path() const { return directory_path_; }
90 // Returns true when cache entries were not loaded to the DB during
91 // initialization.
92 bool cache_file_scan_is_needed() const { return cache_file_scan_is_needed_; }
94 // Destroys this object.
95 void Destroy();
97 // Initializes this object.
98 bool Initialize();
100 // Collects cache info from trashed resource map DB.
101 void RecoverCacheInfoFromTrashedResourceMap(RecoveredCacheInfoMap* out_info);
103 // Sets the largest changestamp.
104 FileError SetLargestChangestamp(int64 largest_changestamp);
106 // Gets the largest changestamp.
107 FileError GetLargestChangestamp(int64* largest_changestamp);
109 // Puts the entry to this storage.
110 FileError PutEntry(const ResourceEntry& entry);
112 // Gets an entry stored in this storage.
113 FileError GetEntry(const std::string& id, ResourceEntry* out_entry);
115 // Removes an entry from this storage.
116 FileError RemoveEntry(const std::string& id);
118 // Returns an object to iterate over entries stored in this storage.
119 scoped_ptr<Iterator> GetIterator();
121 // Returns the ID of the parent's child.
122 FileError GetChild(const std::string& parent_id,
123 const std::string& child_name,
124 std::string* child_id);
126 // Returns the IDs of the parent's children.
127 FileError GetChildren(const std::string& parent_id,
128 std::vector<std::string>* children);
130 // Returns the local ID associated with the given resource ID.
131 FileError GetIdByResourceId(const std::string& resource_id,
132 std::string* out_id);
134 private:
135 friend class ResourceMetadataStorageTest;
137 // To destruct this object, use Destroy().
138 ~ResourceMetadataStorage();
140 // Used to implement Destroy().
141 void DestroyOnBlockingPool();
143 // Returns a string to be used as a key for child entry.
144 static std::string GetChildEntryKey(const std::string& parent_id,
145 const std::string& child_name);
147 // Puts header.
148 FileError PutHeader(const ResourceMetadataHeader& header);
150 // Gets header.
151 FileError GetHeader(ResourceMetadataHeader* out_header);
153 // Checks validity of the data.
154 bool CheckValidity();
156 // Path to the directory where the data is stored.
157 base::FilePath directory_path_;
159 bool cache_file_scan_is_needed_;
161 // Entries stored in this storage.
162 scoped_ptr<leveldb::DB> resource_map_;
164 scoped_refptr<base::SequencedTaskRunner> blocking_task_runner_;
166 DISALLOW_COPY_AND_ASSIGN(ResourceMetadataStorage);
169 } // namespace internal
170 } // namespace drive
172 #endif // CHROME_BROWSER_CHROMEOS_DRIVE_RESOURCE_METADATA_STORAGE_H_