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+/*
+ * Copyright (C) 2010 Max Kellermann <max@duempel.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - 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.
+ *
+ * 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
+ * FOUNDATION 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.
+ */
+
+#ifndef ALLOCATED_ARRAY_HPP
+#define ALLOCATED_ARRAY_HPP
+
+#include "gcc.h"
+
+#include <assert.h>
+#include <algorithm>
+
+/**
+ * An array allocated on the heap with a length determined at runtime.
+ */
+template<class T>
+class AllocatedArray {
+public:
+ typedef size_t size_type;
+
+protected:
+ size_type the_size;
+ T *restrict data;
+
+public:
+ typedef T *iterator;
+ typedef const T *const_iterator;
+
+public:
+ constexpr AllocatedArray():the_size(0), data(nullptr) {}
+
+ explicit AllocatedArray(size_type _size)
+ :the_size(_size), data(new T[the_size]) {
+ assert(size() == 0 || data != nullptr);
+ }
+
+ explicit AllocatedArray(const AllocatedArray &other)
+ :the_size(other.size()), data(new T[the_size]) {
+ assert(size() == 0 || data != nullptr);
+ assert(other.size() == 0 || other.data != nullptr);
+
+ std::copy(other.data, other.data + the_size, data);
+ }
+
+ explicit AllocatedArray(AllocatedArray &&other)
+ :the_size(other.the_size), data(other.data) {
+ other.the_size = 0;
+ other.data = nullptr;
+ }
+
+ ~AllocatedArray() {
+ delete[] data;
+ }
+
+ AllocatedArray &operator=(const AllocatedArray &other) {
+ assert(size() == 0 || data != nullptr);
+ assert(other.size() == 0 || other.data != nullptr);
+
+ if (&other == this)
+ return *this;
+
+ ResizeDiscard(other.size());
+ std::copy(other.begin(), other.end(), data);
+ return *this;
+ }
+
+ AllocatedArray &operator=(AllocatedArray &&other) {
+ std::swap(the_size, other.the_size);
+ std::swap(data, other.data);
+ return *this;
+ }
+
+ /**
+ * Returns true if no memory was allocated so far.
+ */
+ constexpr bool empty() const {
+ return the_size == 0;
+ }
+
+ /**
+ * Returns the number of allocated elements.
+ */
+ constexpr size_type size() const {
+ return the_size;
+ }
+
+ /**
+ * Returns one element. No bounds checking.
+ */
+ T &operator[](size_type i) {
+ assert(i < size());
+
+ return data[i];
+ }
+
+ /**
+ * Returns one constant element. No bounds checking.
+ */
+ const T &operator[](size_type i) const {
+ assert(i < size());
+
+ return data[i];
+ }
+
+ iterator begin() {
+ return data;
+ }
+
+ constexpr const_iterator begin() const {
+ return data;
+ }
+
+ iterator end() {
+ return data + the_size;
+ }
+
+ constexpr const_iterator end() const {
+ return data + the_size;
+ }
+
+ /**
+ * Resizes the array, discarding old data.
+ */
+ void ResizeDiscard(size_type _size) {
+ if (_size == the_size)
+ return;
+
+ delete[] data;
+ the_size = _size;
+ data = new T[the_size];
+
+ assert(size() == 0 || data != nullptr);
+ }
+
+ /**
+ * Grows the array to the specified size, discarding old data.
+ * Similar to ResizeDiscard(), but will never shrink the array to
+ * avoid expensive heap operations.
+ */
+ void GrowDiscard(size_type _size) {
+ if (_size > the_size)
+ ResizeDiscard(_size);
+ }
+
+ /**
+ * Grows the array to the specified size, preserving the value of a
+ * range of elements, starting from the beginning.
+ */
+ void GrowPreserve(size_type _size, size_type preserve) {
+ if (_size <= the_size)
+ return;
+
+ T *new_data = new T[_size];
+ assert(_size == 0 || new_data != nullptr);
+
+ std::move(data, data + preserve, new_data);
+
+ delete[] data;
+ data = new_data;
+ the_size = _size;
+ }
+};
+
+#endif