Ben Murdoch | bb1529c | 2013-08-08 10:24:53 +0100 | [diff] [blame^] | 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|. |
| 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 | |
| 45 | size_t bytes_used() const { return bytes_used_; } |
| 46 | size_t quota() const { return 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_ |