fault_injecting_allocator.h

// Copyright 2025 The Pigweed Authors
//
// Licensed under the Apache License, Version 2.0 (the "License"); you may not
// use this file except in compliance with the License. You may obtain a copy of
// the License at
//
//     https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
// License for the specific language governing permissions and limitations under
// the License.
#pragma once
 
#include "pw_allocator/allocator.h"
#include "pw_allocator/first_fit.h"
 
namespace pw::allocator::test {
 
class FaultInjectingAllocator : public Allocator {
 public:
  explicit constexpr FaultInjectingAllocator(Allocator& allocator)
      : Allocator(allocator.capabilities()),
        allocator_(allocator),
        allow_allocate_(true),
        allow_resize_(true),
        allow_reallocate_(true) {}
 
  void EnableAll() {
    allow_allocate_ = allow_resize_ = allow_reallocate_ = true;
  }
 
  void DisableAll() {
    allow_allocate_ = allow_resize_ = allow_reallocate_ = false;
  }
 
  void EnableAllocate() { allow_allocate_ = true; }
 
  void DisableAllocate() { allow_allocate_ = false; }
 
  void EnableResize() { allow_resize_ = true; }
 
  void DisableResize() { allow_resize_ = false; }
 
  void EnableReallocate() { allow_reallocate_ = true; }
 
  void DisableReallocate() { allow_reallocate_ = false; }
 
  Allocator& real_allocator() { return allocator_; }
 
 private:
  void* DoAllocate(Layout layout) override {
    return allow_allocate_ ? allocator_.Allocate(layout) : nullptr;
  }
  void DoDeallocate(void* ptr) override { allocator_.Deallocate(ptr); }
 
  bool DoResize(void* ptr, size_t new_size) override {
    return allow_resize_ && allocator_.Resize(ptr, new_size);
  }
 
  void* DoReallocate(void* ptr, Layout new_layout) override {
    return allow_reallocate_ ? allocator_.Reallocate(ptr, new_layout) : nullptr;
  }
 
  Allocator& allocator_;
 
  // Flags for whether to allow calls to pass through.
  bool allow_allocate_;
  bool allow_resize_;
  bool allow_reallocate_;
};
 
}  // namespace pw::allocator::test