1 // Copyright 2024 The Pigweed Authors 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); you may not 4 // use this file except in compliance with the License. You may obtain a copy of 5 // the License at 6 // 7 // https://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, WITHOUT 11 // WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the 12 // License for the specific language governing permissions and limitations under 13 // the License. 14 #pragma once 15 16 #include "pw_allocator/config.h" 17 #include "pw_allocator/first_fit.h" 18 19 namespace pw::allocator { 20 21 /// Alias for a default block type that is compatible with 22 /// `LastFitBlockAllocator`. 23 template <typename OffsetType> 24 using LastFitBlock = FirstFitBlock<OffsetType>; 25 26 /// Legacy last fit allocator. 27 /// 28 /// New usages should prefer to use `FirstFitAllocator` directly. 29 /// 30 /// This allocator sets the base type's threshold to value to the maximum value, 31 /// ensuring that all allocations come from the end of the region. 32 template <typename OffsetType = uintptr_t> 33 class PW_ALLOCATOR_DEPRECATED LastFitBlockAllocator 34 : public FirstFitAllocator<LastFitBlock<OffsetType>> { 35 public: 36 using BlockType = LastFitBlock<OffsetType>; 37 38 private: 39 using Base = FirstFitAllocator<BlockType>; 40 41 public: LastFitBlockAllocator()42 constexpr LastFitBlockAllocator() { 43 Base::set_threshold(std::numeric_limits<size_t>::max()); 44 } 45 LastFitBlockAllocator(ByteSpan region)46 explicit LastFitBlockAllocator(ByteSpan region) 47 : Base(region, std::numeric_limits<size_t>::max()) {} 48 }; 49 50 } // namespace pw::allocator 51