Index: services/preferences/public/cpp/scoped_pref_update.h |
diff --git a/services/preferences/public/cpp/scoped_pref_update.h b/services/preferences/public/cpp/scoped_pref_update.h |
new file mode 100644 |
index 0000000000000000000000000000000000000000..9c2dd0c6d949e78e093cc86628014a2336ded45a |
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+++ b/services/preferences/public/cpp/scoped_pref_update.h |
@@ -0,0 +1,197 @@ |
+// Copyright 2017 The Chromium Authors. All rights reserved. |
+// Use of this source code is governed by a BSD-style license that can be |
+// found in the LICENSE file. |
+ |
+#ifndef SERVICES_PREFERENCES_PUBLIC_CPP_SCOPED_PREF_UPDATE_H_ |
+#define SERVICES_PREFERENCES_PUBLIC_CPP_SCOPED_PREF_UPDATE_H_ |
+ |
+#include <memory> |
+#include <set> |
+#include <string> |
+#include <vector> |
+ |
+#include "base/strings/string16.h" |
+#include "base/strings/string_piece.h" |
+#include "base/values.h" |
+ |
+class PrefService; |
+ |
+namespace prefs { |
+class DictionaryValueUpdate; |
+ |
+// An update to a dictionary value pref. |
+class ScopedDictionaryPrefUpdate { |
+ public: |
+ ScopedDictionaryPrefUpdate(PrefService* service, base::StringPiece path); |
+ |
+ // Notifies if necessary. |
+ virtual ~ScopedDictionaryPrefUpdate(); |
+ |
+ virtual DictionaryValueUpdate* Get(); |
+ |
+ DictionaryValueUpdate* operator->(); |
+ |
+ private: |
+ friend class DictionaryValueUpdate; |
+ // If |value_| is not null, triggers a notification of PrefObservers and |
+ // resets |value_|. |
+ void Notify(); |
+ |
+ void RecordPath(const std::vector<std::string>& path); |
+ DictionaryValueUpdate* Insert( |
+ std::unique_ptr<DictionaryValueUpdate> dictionary_value_update); |
+ |
+ // Weak pointer. |
+ PrefService* service_; |
+ // Path of the preference being updated. |
+ std::string path_; |
+ // Cache of value from user pref store (set between Get() and Notify() calls). |
+ DictionaryValueUpdate* value_; |
+ |
+ std::set<std::vector<std::string>> updated_paths_; |
+ |
+ std::vector<std::unique_ptr<DictionaryValueUpdate>> updates_; |
+ |
+ DISALLOW_COPY_AND_ASSIGN(ScopedDictionaryPrefUpdate); |
+}; |
+ |
+// A wrapper around base::DictionaryValue that reports changes to its contents |
+// to a ScopedDictionaryPrefUpdate. |
+class DictionaryValueUpdate { |
+ public: |
+ ~DictionaryValueUpdate(); |
+ bool HasKey(base::StringPiece key) const; |
+ |
+ // Returns the number of Values in this dictionary. |
+ size_t size() const; |
+ |
+ // Returns whether the dictionary is empty. |
+ bool empty() const; |
+ |
+ // Clears any current contents of this dictionary. |
+ void Clear(); |
+ |
+ // Sets the Value associated with the given path starting from this object. |
+ // A path has the form "<key>" or "<key>.<key>.[...]", where "." indexes |
+ // into the next DictionaryValue down. Obviously, "." can't be used |
+ // within a key, but there are no other restrictions on keys. |
+ // If the key at any step of the way doesn't exist, or exists but isn't |
+ // a DictionaryValue, a new DictionaryValue will be created and attached |
+ // to the path in that location. |in_value| must be non-null. |
+ void Set(base::StringPiece path, std::unique_ptr<base::Value> in_value); |
+ |
+ // Convenience forms of Set(). These methods will replace any existing |
+ // value at that path, even if it has a different type. |
+ void SetBoolean(base::StringPiece path, bool in_value); |
+ void SetInteger(base::StringPiece path, int in_value); |
+ void SetDouble(base::StringPiece path, double in_value); |
+ void SetString(base::StringPiece path, base::StringPiece in_value); |
+ void SetString(base::StringPiece path, const base::string16& in_value); |
+ DictionaryValueUpdate* SetDictionary( |
+ base::StringPiece path, |
+ std::unique_ptr<base::DictionaryValue> in_value); |
+ |
+ // Like Set(), but without special treatment of '.'. This allows e.g. URLs to |
+ // be used as paths. |
+ void SetWithoutPathExpansion(base::StringPiece key, |
+ std::unique_ptr<base::Value> in_value); |
+ |
+ // Convenience forms of SetWithoutPathExpansion(). |
+ void SetBooleanWithoutPathExpansion(base::StringPiece path, bool in_value); |
+ void SetIntegerWithoutPathExpansion(base::StringPiece path, int in_value); |
+ void SetDoubleWithoutPathExpansion(base::StringPiece path, double in_value); |
+ void SetStringWithoutPathExpansion(base::StringPiece path, |
+ base::StringPiece in_value); |
+ void SetStringWithoutPathExpansion(base::StringPiece path, |
+ const base::string16& in_value); |
+ DictionaryValueUpdate* SetDictionaryWithoutPathExpansion( |
+ base::StringPiece path, |
+ std::unique_ptr<base::DictionaryValue> in_value); |
+ |
+ // These are convenience forms of Get(). The value will be retrieved |
+ // and the return value will be true if the path is valid and the value at |
+ // the end of the path can be returned in the form specified. |
+ // |out_value| is optional and will only be set if non-NULL. |
+ bool GetBoolean(base::StringPiece path, bool* out_value) const; |
+ bool GetInteger(base::StringPiece path, int* out_value) const; |
+ // Values of both type Type::INTEGER and Type::DOUBLE can be obtained as |
+ // doubles. |
+ bool GetDouble(base::StringPiece path, double* out_value) const; |
+ bool GetString(base::StringPiece path, std::string* out_value) const; |
+ bool GetString(base::StringPiece path, base::string16* out_value) const; |
+ bool GetBinary(base::StringPiece path, const base::Value** out_value) const; |
+ bool GetDictionary(base::StringPiece path, |
+ const base::DictionaryValue** out_value) const; |
+ bool GetDictionary(base::StringPiece path, DictionaryValueUpdate** out_value); |
+ bool GetList(base::StringPiece path, const base::ListValue** out_value) const; |
+ bool GetList(base::StringPiece path, base::ListValue** out_value); |
+ |
+ // Like Get(), but without special treatment of '.'. This allows e.g. URLs to |
+ // be used as paths. |
+ bool GetBooleanWithoutPathExpansion(base::StringPiece key, |
+ bool* out_value) const; |
+ bool GetIntegerWithoutPathExpansion(base::StringPiece key, |
+ int* out_value) const; |
+ bool GetDoubleWithoutPathExpansion(base::StringPiece key, |
+ double* out_value) const; |
+ bool GetStringWithoutPathExpansion(base::StringPiece key, |
+ std::string* out_value) const; |
+ bool GetStringWithoutPathExpansion(base::StringPiece key, |
+ base::string16* out_value) const; |
+ bool GetDictionaryWithoutPathExpansion( |
+ base::StringPiece key, |
+ const base::DictionaryValue** out_value) const; |
+ bool GetDictionaryWithoutPathExpansion(base::StringPiece key, |
+ DictionaryValueUpdate** out_value); |
+ bool GetListWithoutPathExpansion(base::StringPiece key, |
+ const base::ListValue** out_value) const; |
+ bool GetListWithoutPathExpansion(base::StringPiece key, |
+ base::ListValue** out_value); |
+ |
+ // Removes the Value with the specified path from this dictionary (or one |
+ // of its child dictionaries, if the path is more than just a local key). |
+ // If |out_value| is non-NULL, the removed Value will be passed out via |
+ // |out_value|. If |out_value| is NULL, the removed value will be deleted. |
+ // This method returns true if |path| is a valid path; otherwise it will |
+ // return false and the DictionaryValue object will be unchanged. |
+ bool Remove(base::StringPiece path, std::unique_ptr<base::Value>* out_value); |
+ |
+ // Like Remove(), but without special treatment of '.'. This allows e.g. URLs |
+ // to be used as paths. |
+ bool RemoveWithoutPathExpansion(base::StringPiece key, |
+ std::unique_ptr<base::Value>* out_value); |
+ |
+ // Removes a path, clearing out all dictionaries on |path| that remain empty |
+ // after removing the value at |path|. |
+ bool RemovePath(base::StringPiece path, |
+ std::unique_ptr<base::Value>* out_value); |
+ |
+ base::DictionaryValue* AsDictionary(); |
+ const base::DictionaryValue* AsConstDictionary() const; |
+ |
+ private: |
+ friend class ScopedDictionaryPrefUpdate; |
+ |
+ DictionaryValueUpdate(ScopedDictionaryPrefUpdate* update, |
+ base::DictionaryValue* value, |
+ std::vector<std::string> path); |
+ |
+ void RecordPath(base::StringPiece path); |
+ void RecordSplitPath(const std::vector<base::StringPiece>& path); |
+ void RecordKey(base::StringPiece key); |
+ |
+ std::vector<base::StringPiece> SplitPath(base::StringPiece path); |
+ std::vector<std::string> ConcatPath(const std::vector<std::string>& base_path, |
+ base::StringPiece path); |
+ std::vector<std::string> ConcatPath( |
+ const std::vector<std::string>& base_path, |
+ const std::vector<base::StringPiece>& path); |
+ |
+ ScopedDictionaryPrefUpdate* update_; |
+ base::DictionaryValue* value_; |
+ const std::vector<std::string> path_; |
+}; |
+ |
+} // namespace prefs |
+ |
+#endif // SERVICES_PREFERENCES_PUBLIC_CPP_SCOPED_PREF_UPDATE_H_ |