SmallVector.h

/*
Open Asset Import Library (assimp)
----------------------------------------------------------------------
 
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All rights reserved.
 
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* Redistributions of source code must retain the above
  copyright notice, this list of conditions and the
  following disclaimer.
 
* Redistributions in binary form must reproduce the above
  copyright notice, this list of conditions and the
  following disclaimer in the documentation and/or other
  materials provided with the distribution.
 
* Neither the name of the assimp team, nor the names of its
  contributors may be used to endorse or promote products
  derived from this software without specific prior
  written permission of the assimp team.
 
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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*/
 
#pragma once
#ifndef AI_SMALLVECTOR_H_INC
#define AI_SMALLVECTOR_H_INC
 
#ifdef __GNUC__
#   pragma GCC system_header
#endif
 
namespace Assimp {
 
// --------------------------------------------------------------------------------------------
// --------------------------------------------------------------------------------------------
template<typename T, unsigned int Capacity>
class SmallVector {
public:
    SmallVector() : 
            mStorage(mInplaceStorage),
            mSize(0),
            mCapacity(Capacity) {
        // empty
    }
 
    ~SmallVector() {
        if (mStorage != mInplaceStorage) {
            delete [] mStorage;
        }
    }
 
    void push_back(const T& item) {
        if (mSize < mCapacity) {
            mStorage[mSize++] = item;
            return;
        }
        
        push_back_and_grow(item);
    }
 
    void resize(size_t newSize) {
        if (newSize > mCapacity) {
            grow(newSize);
        }
        mSize = newSize;
    }
 
    size_t size() const {
        return mSize;
    }
 
    T* begin() {
        return mStorage;
    }
 
    T* end() {
        return &mStorage[mSize];
    }
 
    T* begin() const {
        return mStorage;
    }
 
    T* end() const {
        return &mStorage[mSize];
    }
 
    SmallVector(const SmallVector &) = delete;
    SmallVector(SmallVector &&) = delete;
    SmallVector &operator = (const SmallVector &) = delete;
    SmallVector &operator = (SmallVector &&) = delete;
 
private:
    void grow( size_t newCapacity) {
        T* oldStorage = mStorage;
        T* newStorage = new T[newCapacity];
 
        std::memcpy(newStorage, oldStorage, mSize * sizeof(T));
 
        mStorage = newStorage;
        mCapacity = newCapacity;
 
        if (oldStorage != mInplaceStorage) {
            delete [] oldStorage;
        }
    }
 
    void push_back_and_grow(const T& item) {
        grow(mCapacity + Capacity);
 
        mStorage[mSize++] = item;
    }
 
    T* mStorage;
    size_t mSize;
    size_t mCapacity;
    T mInplaceStorage[Capacity];
};
 
} // end namespace Assimp
 
#endif // !! AI_SMALLVECTOR_H_INC