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-rw-r--r--NorthstarDLL/include/spdlog/details/circular_q.h141
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diff --git a/NorthstarDLL/include/spdlog/details/circular_q.h b/NorthstarDLL/include/spdlog/details/circular_q.h
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+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+// circular q view of std::vector.
+#pragma once
+
+#include <vector>
+#include <cassert>
+
+namespace spdlog {
+namespace details {
+template<typename T>
+class circular_q
+{
+ size_t max_items_ = 0;
+ typename std::vector<T>::size_type head_ = 0;
+ typename std::vector<T>::size_type tail_ = 0;
+ size_t overrun_counter_ = 0;
+ std::vector<T> v_;
+
+public:
+ using value_type = T;
+
+ // empty ctor - create a disabled queue with no elements allocated at all
+ circular_q() = default;
+
+ explicit circular_q(size_t max_items)
+ : max_items_(max_items + 1) // one item is reserved as marker for full q
+ , v_(max_items_)
+ {}
+
+ circular_q(const circular_q &) = default;
+ circular_q &operator=(const circular_q &) = default;
+
+ // move cannot be default,
+ // since we need to reset head_, tail_, etc to zero in the moved object
+ circular_q(circular_q &&other) SPDLOG_NOEXCEPT
+ {
+ copy_moveable(std::move(other));
+ }
+
+ circular_q &operator=(circular_q &&other) SPDLOG_NOEXCEPT
+ {
+ copy_moveable(std::move(other));
+ return *this;
+ }
+
+ // push back, overrun (oldest) item if no room left
+ void push_back(T &&item)
+ {
+ if (max_items_ > 0)
+ {
+ v_[tail_] = std::move(item);
+ tail_ = (tail_ + 1) % max_items_;
+
+ if (tail_ == head_) // overrun last item if full
+ {
+ head_ = (head_ + 1) % max_items_;
+ ++overrun_counter_;
+ }
+ }
+ }
+
+ // Return reference to the front item.
+ // If there are no elements in the container, the behavior is undefined.
+ const T &front() const
+ {
+ return v_[head_];
+ }
+
+ T &front()
+ {
+ return v_[head_];
+ }
+
+ // Return number of elements actually stored
+ size_t size() const
+ {
+ if (tail_ >= head_)
+ {
+ return tail_ - head_;
+ }
+ else
+ {
+ return max_items_ - (head_ - tail_);
+ }
+ }
+
+ // Return const reference to item by index.
+ // If index is out of range 0…size()-1, the behavior is undefined.
+ const T &at(size_t i) const
+ {
+ assert(i < size());
+ return v_[(head_ + i) % max_items_];
+ }
+
+ // Pop item from front.
+ // If there are no elements in the container, the behavior is undefined.
+ void pop_front()
+ {
+ head_ = (head_ + 1) % max_items_;
+ }
+
+ bool empty() const
+ {
+ return tail_ == head_;
+ }
+
+ bool full() const
+ {
+ // head is ahead of the tail by 1
+ if (max_items_ > 0)
+ {
+ return ((tail_ + 1) % max_items_) == head_;
+ }
+ return false;
+ }
+
+ size_t overrun_counter() const
+ {
+ return overrun_counter_;
+ }
+
+private:
+ // copy from other&& and reset it to disabled state
+ void copy_moveable(circular_q &&other) SPDLOG_NOEXCEPT
+ {
+ max_items_ = other.max_items_;
+ head_ = other.head_;
+ tail_ = other.tail_;
+ overrun_counter_ = other.overrun_counter_;
+ v_ = std::move(other.v_);
+
+ // put &&other in disabled, but valid state
+ other.max_items_ = 0;
+ other.head_ = other.tail_ = 0;
+ other.overrun_counter_ = 0;
+ }
+};
+} // namespace details
+} // namespace spdlog