1 // Copyright (c) 2011 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 CHROME_COMMON_PERSISTENT_PREF_STORE_H_ 6 #define CHROME_COMMON_PERSISTENT_PREF_STORE_H_ 7 #pragma once 8 9 #include <string> 10 11 #include <chrome/common/pref_store.h> 12 13 // This interface is complementary to the PrefStore interface, declaring 14 // additional functionality that adds support for setting values and persisting 15 // the data to some backing store. 16 class PersistentPrefStore : public PrefStore { 17 public: ~PersistentPrefStore()18 virtual ~PersistentPrefStore() {} 19 20 // Unique integer code for each type of error so we can report them 21 // distinctly in a histogram. 22 // NOTE: Don't change the order here as it will change the server's meaning 23 // of the histogram. 24 enum PrefReadError { 25 PREF_READ_ERROR_NONE = 0, 26 PREF_READ_ERROR_JSON_PARSE, 27 PREF_READ_ERROR_JSON_TYPE, 28 PREF_READ_ERROR_ACCESS_DENIED, 29 PREF_READ_ERROR_FILE_OTHER, 30 PREF_READ_ERROR_FILE_LOCKED, 31 PREF_READ_ERROR_NO_FILE, 32 PREF_READ_ERROR_JSON_REPEAT, 33 PREF_READ_ERROR_OTHER, 34 PREF_READ_ERROR_FILE_NOT_SPECIFIED 35 }; 36 37 // Equivalent to PrefStore::GetValue but returns a mutable value. 38 virtual ReadResult GetMutableValue(const std::string& key, 39 Value** result) = 0; 40 41 // Triggers a value changed notification. This function needs to be called 42 // if one retrieves a list or dictionary with GetMutableValue and change its 43 // value. SetValue takes care of notifications itself. Note that 44 // ReportValueChanged will trigger notifications even if nothing has changed. 45 virtual void ReportValueChanged(const std::string& key) = 0; 46 47 // Sets a |value| for |key| in the store. Assumes ownership of |value|, which 48 // must be non-NULL. 49 virtual void SetValue(const std::string& key, Value* value) = 0; 50 51 // Same as SetValue, but doesn't generate notifications. This is used by 52 // PrefService::GetMutableUserPref() in order to put empty entries 53 // into the user pref store. Using SetValue is not an option since existing 54 // tests rely on the number of notifications generated. 55 virtual void SetValueSilently(const std::string& key, Value* value) = 0; 56 57 // Removes the value for |key|. 58 virtual void RemoveValue(const std::string& key) = 0; 59 60 // Whether the store is in a pseudo-read-only mode where changes are not 61 // actually persisted to disk. This happens in some cases when there are 62 // read errors during startup. 63 virtual bool ReadOnly() const = 0; 64 65 // Reads the preferences from disk. 66 virtual PrefReadError ReadPrefs() = 0; 67 68 // Writes the preferences to disk immediately. 69 virtual bool WritePrefs() = 0; 70 71 // Schedules an asynchronous write operation. 72 virtual void ScheduleWritePrefs() = 0; 73 74 // Lands any pending writes to disk. 75 virtual void CommitPendingWrite() = 0; 76 }; 77 78 #endif // CHROME_COMMON_PERSISTENT_PREF_STORE_H_ 79