5 * Copyright (c) 2021 Samsung Electronics Co., Ltd.
7 * Licensed under the Apache License, Version 2.0 (the "License");
8 * you may not use this file except in compliance with the License.
9 * You may obtain a copy of the License at
11 * http://www.apache.org/licenses/LICENSE-2.0
13 * Unless required by applicable law or agreed to in writing, software
14 * distributed under the License is distributed on an "AS IS" BASIS,
15 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 * See the License for the specific language governing permissions and
17 * limitations under the License.
22 #include <cstdint> // uint32_t
25 #include <dali/public-api/common/dali-vector.h>
32 * FreeList operates by connecting unused elements of a vector together in a linked list using the
33 * value of each unused cell as a pointer to the next. When a new element is added, it will be added
34 * to the first free index of the vector and the new free index will be the value which was on that
51 ~FreeList() = default;
54 * Adds a new item to the list. If there is no more space in the vector it will
55 * allocate more space, otherwise, it will use the first free cell to store the
56 * new value and will update the first free index.
58 * @param[in] value The value to add
59 * @return The index where the value has been added
61 uint32_t Add(uint32_t value)
63 const uint32_t size = static_cast<uint32_t>(mData.Size()); // 4,294,967,295 entries is enough
64 if(mData.Empty() || mFirstFreeIndex == size)
66 //Make room for another item
67 mData.PushBack(size + 1);
68 mFirstFreeIndex = size;
71 //Update first free index
72 uint32_t index = mFirstFreeIndex;
73 mFirstFreeIndex = mData[mFirstFreeIndex];
80 * Removes the item at position "index" from the list and
81 * updates the first free index
83 * @param[in] index The index of the element to remove
85 void Remove(uint32_t index)
87 mData[index] = mFirstFreeIndex;
88 mFirstFreeIndex = index;
94 * @param[in] index Index of the element.
95 * @return Reference to the element for given index.
97 uint32_t& operator[](uint32_t index)
103 * Subscript operator (const).
105 * @param[in] index Index of the element.
106 * @return Reference to the element for given index.
108 uint32_t operator[](uint32_t index) const
114 Dali::Vector<uint32_t> mData; ///< data
115 uint32_t mFirstFreeIndex; ///< Index where a new element will be added
118 } // namespace Internal
121 #endif /* FREE_LIST_H_ */