xref: /aosp_15_r20/external/pigweed/pw_allocator/bump_allocator.cc (revision 61c4878ac05f98d0ceed94b57d316916de578985)
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 #include "pw_allocator/bump_allocator.h"
16 
17 #include "pw_allocator/buffer.h"
18 #include "pw_bytes/alignment.h"
19 
20 namespace pw::allocator {
21 
Init(ByteSpan region)22 void BumpAllocator::Init(ByteSpan region) {
23   Reset();
24   remaining_ = region;
25 }
26 
DoAllocate(Layout layout)27 void* BumpAllocator::DoAllocate(Layout layout) {
28   size_t remaining = remaining_.size();
29   ByteSpan region = GetAlignedSubspan(remaining_, layout.alignment());
30   if (region.size() < layout.size()) {
31     return nullptr;
32   }
33   remaining_ = region.subspan(layout.size());
34   allocated_ += remaining - remaining_.size();
35   return region.data();
36 }
37 
DoDeallocate(void *)38 void BumpAllocator::DoDeallocate(void*) {}
39 
Reset()40 void BumpAllocator::Reset() {
41   if (owned_ != nullptr) {
42     owned_->Destroy();
43   }
44   remaining_ = ByteSpan();
45 }
46 
47 }  // namespace pw::allocator
48