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. 4 5 #ifndef CONTENT_BROWSER_DOM_STORAGE_DOM_STORAGE_DATABASE_H_ 6 #define CONTENT_BROWSER_DOM_STORAGE_DOM_STORAGE_DATABASE_H_ 7 8 #include <map> 9 10 #include "base/files/file_path.h" 11 #include "base/gtest_prod_util.h" 12 #include "base/memory/scoped_ptr.h" 13 #include "base/strings/nullable_string16.h" 14 #include "base/strings/string16.h" 15 #include "content/common/content_export.h" 16 #include "content/common/dom_storage/dom_storage_types.h" 17 #include "sql/connection.h" 18 19 namespace content { 20 21 // Represents a SQLite based backing for DOM storage data. This 22 // class is designed to be used on a single thread. 23 class CONTENT_EXPORT DOMStorageDatabase { 24 public: 25 static base::FilePath GetJournalFilePath(const base::FilePath& database_path); 26 27 explicit DOMStorageDatabase(const base::FilePath& file_path); 28 virtual ~DOMStorageDatabase(); // virtual for unit testing 29 30 // Reads all the key, value pairs stored in the database and returns 31 // them. |result| is assumed to be empty and any duplicate keys will 32 // be overwritten. If the database exists on disk then it will be 33 // opened. If it does not exist then it will not be created and 34 // |result| will be unmodified. 35 void ReadAllValues(DOMStorageValuesMap* result); 36 37 // Updates the backing database. Will remove all keys before updating 38 // the database if |clear_all_first| is set. Then all entries in 39 // |changes| will be examined - keys mapped to a null NullableString16 40 // will be removed and all others will be inserted/updated as appropriate. 41 bool CommitChanges(bool clear_all_first, const DOMStorageValuesMap& changes); 42 43 // Simple getter for the path we were constructed with. file_path()44 const base::FilePath& file_path() const { return file_path_; } 45 46 protected: 47 // Constructor that uses an in-memory sqlite database, for testing. 48 DOMStorageDatabase(); 49 50 private: 51 friend class LocalStorageDatabaseAdapter; 52 FRIEND_TEST_ALL_PREFIXES(DOMStorageDatabaseTest, SimpleOpenAndClose); 53 FRIEND_TEST_ALL_PREFIXES(DOMStorageDatabaseTest, TestLazyOpenIsLazy); 54 FRIEND_TEST_ALL_PREFIXES(DOMStorageDatabaseTest, TestDetectSchemaVersion); 55 FRIEND_TEST_ALL_PREFIXES(DOMStorageDatabaseTest, 56 TestLazyOpenUpgradesDatabase); 57 FRIEND_TEST_ALL_PREFIXES(DOMStorageDatabaseTest, SimpleWriteAndReadBack); 58 FRIEND_TEST_ALL_PREFIXES(DOMStorageDatabaseTest, WriteWithClear); 59 FRIEND_TEST_ALL_PREFIXES(DOMStorageDatabaseTest, 60 UpgradeFromV1ToV2WithData); 61 FRIEND_TEST_ALL_PREFIXES(DOMStorageDatabaseTest, TestSimpleRemoveOneValue); 62 FRIEND_TEST_ALL_PREFIXES(DOMStorageDatabaseTest, 63 TestCanOpenAndReadWebCoreDatabase); 64 FRIEND_TEST_ALL_PREFIXES(DOMStorageDatabaseTest, 65 TestCanOpenFileThatIsNotADatabase); 66 FRIEND_TEST_ALL_PREFIXES(DOMStorageAreaTest, BackingDatabaseOpened); 67 FRIEND_TEST_ALL_PREFIXES(DOMStorageAreaTest, CommitTasks); 68 FRIEND_TEST_ALL_PREFIXES(DOMStorageAreaTest, PurgeMemory); 69 70 enum SchemaVersion { 71 INVALID, 72 V1, 73 V2 74 }; 75 76 // Open the database at file_path_ if it exists already and creates it if 77 // |create_if_needed| is true. 78 // Ensures we are at the correct database version and creates or updates 79 // tables as necessary. Returns false on failure. 80 bool LazyOpen(bool create_if_needed); 81 82 // Analyses the database to verify that the connection that is open is indeed 83 // a valid database and works out the schema version. 84 SchemaVersion DetectSchemaVersion(); 85 86 // Creates the database table at V2. Returns true if the table was created 87 // successfully, false otherwise. Will return false if the table already 88 // exists. 89 bool CreateTableV2(); 90 91 // If we have issues while trying to open the file (corrupted databse, 92 // failing to upgrade, that sort of thing) this function will remove 93 // the file from disk and attempt to create a new database from 94 // scratch. 95 bool DeleteFileAndRecreate(); 96 97 // Version 1 -> 2 migrates the value column in the ItemTable from a TEXT 98 // to a BLOB. Exisitng data is preserved on success. Returns false if the 99 // upgrade failed. If true is returned, the database is guaranteed to be at 100 // version 2. 101 bool UpgradeVersion1To2(); 102 103 void Close(); IsOpen()104 bool IsOpen() const { return db_.get() ? db_->is_open() : false; } 105 106 // Initialization code shared between the two constructors of this class. 107 void Init(); 108 109 // Path to the database on disk. 110 const base::FilePath file_path_; 111 scoped_ptr<sql::Connection> db_; 112 bool failed_to_open_; 113 bool tried_to_recreate_; 114 bool known_to_be_empty_; 115 }; 116 117 } // namespace content 118 119 #endif // CONTENT_BROWSER_DOM_STORAGE_DOM_STORAGE_DATABASE_H_ 120