lib/magma/src/magma_util/simple_allocator.h

// Copyright 2016 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef SIMPLE_ALLOCATOR_H
#define SIMPLE_ALLOCATOR_H

#include "address_space_allocator.h"
#include <list>

namespace magma {

class SimpleAllocator final : public AddressSpaceAllocator {
public:
    static std::unique_ptr<SimpleAllocator> Create(uint64_t base, size_t size);

    bool Alloc(size_t size, uint8_t align_pow2, uint64_t* addr_out) override;
    bool Free(uint64_t addr) override;
    bool GetSize(uint64_t addr, size_t* size_out) override;

private:
    SimpleAllocator(uint64_t base, size_t size);

    struct Region {
        Region(uint64_t base, size_t size);
        uint64_t base;
        size_t size;
    };

    bool CheckGap(SimpleAllocator::Region* prev, SimpleAllocator::Region* next, uint64_t align,
                  size_t size, uint64_t* addr_out, bool* continue_search_out);

    DISALLOW_COPY_AND_ASSIGN(SimpleAllocator);

private:
    std::list<SimpleAllocator::Region>::iterator FindRegion(uint64_t addr);

    std::list<SimpleAllocator::Region> regions_;
};

} // namespace magma

#endif // SIMPLE_ALLOCATOR_H