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_COMMON_DOM_STORAGE_DOM_STORAGE_MAP_H_ 6 #define CONTENT_COMMON_DOM_STORAGE_DOM_STORAGE_MAP_H_ 7 8 #include <map> 9 10 #include "base/memory/ref_counted.h" 11 #include "base/strings/nullable_string16.h" 12 #include "base/strings/string16.h" 13 #include "content/common/content_export.h" 14 #include "content/common/dom_storage/dom_storage_types.h" 15 16 namespace content { 17 18 // A wrapper around a std::map that adds refcounting and 19 // tracks the size in bytes of the keys/values, enforcing a quota. 20 // See class comments for DOMStorageContextImpl for a larger overview. 21 class CONTENT_EXPORT DOMStorageMap 22 : public base::RefCountedThreadSafe<DOMStorageMap> { 23 public: 24 explicit DOMStorageMap(size_t quota); 25 26 unsigned Length() const; 27 base::NullableString16 Key(unsigned index); 28 base::NullableString16 GetItem(const base::string16& key) const; 29 bool SetItem(const base::string16& key, const base::string16& value, 30 base::NullableString16* old_value); 31 bool RemoveItem(const base::string16& key, base::string16* old_value); 32 33 // Swaps this instances values_ with |map|. 34 // Note: to grandfather in pre-existing files that are overbudget, 35 // this method does not do quota checking. 36 void SwapValues(DOMStorageValuesMap* map); 37 38 // Writes a copy of the current set of values_ to the |map|. ExtractValues(DOMStorageValuesMap * map)39 void ExtractValues(DOMStorageValuesMap* map) const { *map = values_; } 40 41 // Creates a new instance of DOMStorageMap containing 42 // a deep copy of values_. 43 DOMStorageMap* DeepCopy() const; 44 bytes_used()45 size_t bytes_used() const { return bytes_used_; } quota()46 size_t quota() const { return quota_; } set_quota(size_t quota)47 void set_quota(size_t quota) { quota_ = quota; } 48 49 private: 50 friend class base::RefCountedThreadSafe<DOMStorageMap>; 51 ~DOMStorageMap(); 52 53 void ResetKeyIterator(); 54 55 DOMStorageValuesMap values_; 56 DOMStorageValuesMap::const_iterator key_iterator_; 57 unsigned last_key_index_; 58 size_t bytes_used_; 59 size_t quota_; 60 }; 61 62 } // namespace content 63 64 #endif // CONTENT_COMMON_DOM_STORAGE_DOM_STORAGE_MAP_H_ 65