1 // Copyright 2023 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 
15 #pragma once
16 #include "pw_bluetooth_sapphire/internal/host/common/byte_buffer.h"
17 
18 namespace bt {
19 
20 // NOTE: Tweak these as needed.
21 constexpr size_t kSmallBufferSize = 64;
22 constexpr size_t kLargeBufferSize = 2048;
23 
24 constexpr size_t kMaxNumSlabs = 100;
25 constexpr size_t kSlabSize = 32767;
26 
27 // Returns a slab-allocated byte buffer with |size| bytes of capacity. The
28 // underlying allocation occupies |kSmallBufferSize| or |kLargeBufferSize| bytes
29 // of memory, unless:
30 //  * |size| is 0, which returns a zero-sized byte buffer with no underlying
31 //  slab allocation.
32 //  * |size| exceeds |kLargeBufferSize|, which falls back to the system
33 //  allocator.
34 //    NOTE: In this case, if allocation fails, panic.
35 //
36 // Returns nullptr for failures to allocate.
37 [[nodiscard]] MutableByteBufferPtr NewBuffer(size_t size);
38 
39 }  // namespace bt
40