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/*
* Copyright (C) 2013, 2015-2016 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. ``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 APPLE INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#pragma once
namespace WTF {
template<typename T>
class Insertion {
WTF_MAKE_FAST_ALLOCATED;
public:
Insertion() { }
template<typename U>
Insertion(size_t index, U&& element)
: m_index(index)
, m_element(std::forward<U>(element))
{
}
size_t index() const { return m_index; }
const T& element() const { return m_element; }
T& element() { return m_element; }
bool operator<(const Insertion& other) const
{
return m_index < other.m_index;
}
private:
size_t m_index { 0 };
T m_element { };
};
template<typename TargetVectorType, typename InsertionVectorType>
size_t executeInsertions(TargetVectorType& target, InsertionVectorType& insertions)
{
size_t numInsertions = insertions.size();
if (!numInsertions)
return 0;
size_t originalTargetSize = target.size();
target.grow(target.size() + numInsertions);
size_t lastIndex = target.size();
for (size_t indexInInsertions = numInsertions; indexInInsertions--;) {
ASSERT(!indexInInsertions || insertions[indexInInsertions].index() >= insertions[indexInInsertions - 1].index());
ASSERT_UNUSED(originalTargetSize, insertions[indexInInsertions].index() <= originalTargetSize);
size_t firstIndex = insertions[indexInInsertions].index() + indexInInsertions;
size_t indexOffset = indexInInsertions + 1;
for (size_t i = lastIndex; --i > firstIndex;)
target[i] = WTFMove(target[i - indexOffset]);
target[firstIndex] = WTFMove(insertions[indexInInsertions].element());
lastIndex = firstIndex;
}
insertions.shrink(0);
return numInsertions;
}
} // namespace WTF
using WTF::Insertion;
using WTF::executeInsertions;