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
|
// Copyright 2014 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef COMPONENTS_PREFS_WRITEABLE_PREF_STORE_H_
#define COMPONENTS_PREFS_WRITEABLE_PREF_STORE_H_
#include <stdint.h>
#include <memory>
#include <set>
#include <string>
#include <vector>
#include "components/prefs/pref_store.h"
namespace base {
class Value;
}
// A pref store that can be written to as well as read from.
class COMPONENTS_PREFS_EXPORT WriteablePrefStore : public PrefStore {
public:
// PrefWriteFlags can be used to change the way a pref will be written to
// storage.
enum PrefWriteFlags : uint32_t {
// No flags are specified.
DEFAULT_PREF_WRITE_FLAGS = 0,
// This marks the pref as "lossy". There is no strict time guarantee on when
// a lossy pref will be persisted to permanent storage when it is modified.
LOSSY_PREF_WRITE_FLAG = 1 << 1
};
WriteablePrefStore() {}
WriteablePrefStore(const WriteablePrefStore&) = delete;
WriteablePrefStore& operator=(const WriteablePrefStore&) = delete;
// Sets a |value| for |key| in the store. |flags| is a bitmask of
// PrefWriteFlags.
virtual void SetValue(const std::string& key,
base::Value value,
uint32_t flags) = 0;
// Removes the value for |key|.
virtual void RemoveValue(const std::string& key, uint32_t flags) = 0;
// Equivalent to PrefStore::GetValue but returns a mutable value.
virtual bool GetMutableValue(const std::string& key,
base::Value** result) = 0;
// Triggers a value changed notification. This function or
// ReportSubValuesChanged needs to be called if one retrieves a list or
// dictionary with GetMutableValue and change its value. SetValue takes care
// of notifications itself. Note that ReportValueChanged will trigger
// notifications even if nothing has changed. |flags| is a bitmask of
// PrefWriteFlags.
virtual void ReportValueChanged(const std::string& key, uint32_t flags) = 0;
// Triggers a value changed notification for |path_components| in the |key|
// pref. This function or ReportValueChanged needs to be called if one
// retrieves a list or dictionary with GetMutableValue and change its value.
// SetValue takes care of notifications itself. Note that
// ReportSubValuesChanged will trigger notifications even if nothing has
// changed. |flags| is a bitmask of PrefWriteFlags.
virtual void ReportSubValuesChanged(
const std::string& key,
std::set<std::vector<std::string>> path_components,
uint32_t flags);
// Same as SetValue, but doesn't generate notifications. This is used by
// PrefService::GetMutableUserPref() in order to put empty entries
// into the user pref store. Using SetValue is not an option since existing
// tests rely on the number of notifications generated. |flags| is a bitmask
// of PrefWriteFlags.
virtual void SetValueSilently(const std::string& key,
base::Value value,
uint32_t flags) = 0;
// Clears all the preferences which names start with |prefix| and doesn't
// generate update notifications.
virtual void RemoveValuesByPrefixSilently(const std::string& prefix) = 0;
protected:
~WriteablePrefStore() override {}
};
#endif // COMPONENTS_PREFS_WRITEABLE_PREF_STORE_H_
|
