a deque added

include/cont/deque.h

@@ -0,0 +1,193 @@
+/*!
+ * \file cont/deque.h
+ * \brief
+ *      A statically allocated deque based on a ring buffer.
+ *
+ * \copyright Copyright (C) 2021 Christos Choutouridis <christos@choutouridis.net>
+ *
+ * <dl class=\"section copyright\"><dt>License</dt><dd>
+ * The MIT License (MIT)
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ * </dd></dl>
+ */
+
+#ifndef TBX_CONT_DEQUE_H_
+#define TBX_CONT_DEQUE_H_
+
+#include <core/core.h>
+#include <core/ring_iterator.h>
+
+#include <array>
+
+namespace tbx {
+
+/*!
+ * \class deque
+ * \brief
+ *      A statically allocated deque based on a ring buffer
+ *
+ * The deque uses two ring_iterators one for the front and one for the rear. The iterators
+ * are pointing to the next available spot, not on the last inserted spot. This way at the
+ * initialization the iterators wont "pretend" to point to a valid item .
+ *
+ * We use a ring buffer of size \c N+1. We start the front iterator at the last location of the buffer
+ * and the rear on the first. This way when the queue is full the iterators are pointing to the same location.
+ *
+ * \tparam Data_t   The char-like queued item type. Usually \c char
+ * \tparam N        The size of deque
+ */
+template <typename Data_t, size_t N>
+class deque {
+    public:
+        // meta-identity type
+        using type              = deque<Data_t, N>;
+        using buffer_t          = std::array<Data_t, N+1>;  // We need N+1 spaces ring buffer for N spaces deque
+        using iterator_t        = ring_iterator<Data_t*, N+1>;
+
+        // STL
+        using value_type        = Data_t;
+        using reference         = Data_t&;
+        using const_reference   = const Data_t&;
+        using pointer           = Data_t*;
+        using const_pointer     = const Data_t*;
+        using iterator          = iterator_t;
+        using const_iterator    = const iterator_t;
+        using reverse_iterator  = std::reverse_iterator<iterator>;
+        using const_reverse_iterator = std::reverse_iterator<const_iterator>;
+
+    //! \name Constructor / Destructor
+    //! @{
+    public:
+        //! Default constructor
+        deque () noexcept :
+            data_{},
+            f{data_.data(), N},
+            r{data_.data()} { }
+
+        //! fill contructor
+        deque(const Data_t& value) noexcept {
+            data_.fill(value);
+            f = iterator(data_.data(), N);
+            r = iterator(data_.data(), N);
+        }
+
+        //! Initializer list contructor
+        template <typename ...It>
+        deque(It&& ...it) noexcept :
+            data_{{std::forward<It>(it)...}},
+            f(data_.data(), sizeof...(It)),
+            r(data_.data(), sizeof...(It)) { }
+
+        deque(const deque&) = delete;                   //!< No copies
+        deque& operator= (const deque&) = delete;       //!< No copy assignments
+        ~deque () = default;                            //!< default destructor
+    //! @}
+
+    //! \name Iterators
+    //! @{
+    public:
+        iterator begin() noexcept               { return f+1; }
+        const_iterator begin() const noexcept   { return f+1; }
+        const_iterator cbegin() const noexcept  { return f+1; }
+
+        iterator end() noexcept                 { return r; }
+        const_iterator end() const noexcept     { return r; }
+        const_iterator cend() const noexcept    { return r; }
+
+        reverse_iterator rbegin() noexcept              { return r; }
+        const_reverse_iterator rbegin() const noexcept  { return r; }
+        const_reverse_iterator crbegin() const noexcept { return r; }
+
+        reverse_iterator rend() noexcept                { return f+1; }
+        const_reverse_iterator rend() const noexcept    { return f+1; }
+        const_reverse_iterator crend() const noexcept   { return f+1; }
+    //! @}
+
+    //! \name Capacity
+    //! @{
+    public:
+        //! \return The size of the deque. The items currently in queue.
+        size_t size() noexcept {
+            return full() ? N: (r - f) -1;
+        }
+        //! \return The maximum size of the deque. The items the queue can hold.
+        size_t max_size() noexcept { return N; }
+        //! \return The capacity of the deque. The items the queue can hold.
+        size_t capacity() noexcept { return N; }
+        //! \return True if the deque is empty
+        bool   empty()    noexcept { return size() == 0 ? true : false; }
+        //! \return True if the deque is full
+        bool   full()     noexcept { return (r == f) ? true : false; }
+    //! @}
+
+    //! \name Member access
+    //! @{
+    public:
+        //! \brief  Clears-empty the deque and return it to init state, without
+        //!         really deleting the contents.
+        void clear() noexcept {
+            f = iterator_t(data_.data(), N);
+            r = iterator_t(data_.data());
+        }
+        //! \brief      Push an item in the front of the deque
+        //! \param it   The item to push
+        void push_front (const Data_t& it) {
+            if (full())     return;
+            *f-- = it;
+        }
+        //! \brief      Extract an item from the front of the deque and remove it from the deque
+        //! \param it   The item to push
+        Data_t pop_front () {
+            if (empty())    return Data_t{};
+            return *++f;
+        }
+        //! \brief      Push an item in the back of the deque
+        //! \param it   The item to push
+        void push_back (const Data_t& it) {
+            if (full())     return;
+            *r++ = it;
+        }
+        //! \brief      Extract an item from the back of the deque and remove it from the deque
+        //! \param it   The item to push
+        Data_t pop_back () {
+            if (empty())    return Data_t{};
+            return *--r;
+        }
+
+        //! \brief      Get a reference to the item in the front of the deque without extracting it.
+        //! \return     Reference to the item
+        Data_t& front() noexcept { return *(f+1); }
+        const Data_t& front() const noexcept { return *(f+1); }
+
+        //! \brief      Get a reference to the item in the front of the deque without extracting it.
+        //! \return     Reference to the item
+        Data_t& back() noexcept { return *(r-1); }
+        const Data_t& back() const noexcept { return *(r-1); }
+
+    //! @}
+    private:
+        buffer_t    data_{};            //!< The statically allocated buffer
+        iterator_t  f{data_.data(), N}; //!< A ring iterator for the front (points to the next available location)
+        iterator_t  r{data_.data()};    //!< A ring iterator for the rear (points to the next available location).
+};
+
+}
+
+#endif /* TBX_CONT_ADEQUE_H_ */

test/tests/deque.cpp

@@ -0,0 +1,191 @@
+/*!
+ * \file deque.cpp
+ * \brief
+ *      Unit tests for deque
+ *
+ * \copyright Copyright (C) 2020 Christos Choutouridis <christos@choutouridis.net>
+ *
+ * <dl class=\"section copyright\"><dt>License</dt><dd>
+ * The MIT License (MIT)
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ * </dd></dl>
+ *
+ */
+#include <cont/deque.h>
+#include <gtest/gtest.h>
+
+namespace Tdeque {
+    using namespace tbx;
+
+
+    // Test construction
+    TEST(Tdeque, contruct) {
+        deque<int, 8> q1;
+        deque<int, 8> q2{1, 2, 3, 4, 5, 6, 7, 8};
+
+        EXPECT_EQ (8UL, q1.capacity());
+        EXPECT_EQ (8UL, q2.capacity());
+    }
+
+    // simple push-pop functionality
+    TEST(Tdeque, push_pop) {
+        deque<int, 8> q1;
+        deque<int, 8> q2{1, 2, 3, 4, 5, 6, 7, 8};
+
+        q1.push_front(1);
+        q1.push_front(2);
+        EXPECT_EQ (1, q1.pop_back());
+        EXPECT_EQ (2, q1.pop_back());
+
+        q1.push_back(1);
+        q1.push_back(2);
+        EXPECT_EQ (1, q1.pop_front());
+        EXPECT_EQ (2, q1.pop_front());
+
+        q1.push_front(2);
+        q1.push_back(3);
+        q1.push_front(1);
+        q1.push_back(4);
+
+        for (int i=1 ; i<= 4 ; ++i)
+            EXPECT_EQ ((int)i, q1.pop_front());
+    }
+
+    // front-back
+    TEST(Tdeque, front_back) {
+        deque<int, 8> q1;
+        deque<int, 8> q2{1, 2, 3, 4, 5, 6, 7, 8};
+
+        q1.push_front(2);
+        q1.push_front(1);
+        q1.push_back(3);
+        q1.push_back(4);
+
+        EXPECT_EQ (1, q1.front());
+        EXPECT_EQ (4, q1.back());
+        EXPECT_EQ (1, q2.front());
+        EXPECT_EQ (8, q2.back());
+    }
+
+    // capacity
+    TEST(Tdeque, capacity) {
+        deque<int, 8> q1;
+        deque<int, 8> q2{1, 2, 3, 4, 5, 6, 7, 8};
+
+        q1.push_back(1);
+        q1.clear();
+        EXPECT_EQ (true, q1.empty());
+        EXPECT_EQ (true, q2.full());
+
+        EXPECT_EQ (8UL, q1.capacity());
+        EXPECT_EQ (8UL, q2.capacity());
+
+        EXPECT_EQ (0UL, q1.size());
+        EXPECT_EQ (8UL, q2.size());
+
+        q1.push_back(2);
+        EXPECT_EQ (1UL, q1.size());
+        q1.push_front(1);
+        EXPECT_EQ (2UL, q1.size());
+
+        q1.pop_back();
+        EXPECT_EQ (1UL, q1.size());
+        q1.pop_front();
+        EXPECT_EQ (0UL, q1.size());
+    }
+
+    // push-pop limits
+    TEST (Tdeque, push_pop_limits) {
+        deque<int, 8> q1;
+        deque<int, 8> q2{1, 2, 3, 4, 5, 6, 7, 8};
+
+        EXPECT_EQ (int{}, q1.pop_back());
+        EXPECT_EQ (0UL, q1.size());
+        EXPECT_EQ (true, q1.empty());
+        EXPECT_EQ (false, q1.full());
+
+        EXPECT_EQ (int{}, q1.pop_front());
+        EXPECT_EQ (0UL, q1.size());
+        EXPECT_EQ (true, q1.empty());
+        EXPECT_EQ (false, q1.full());
+
+        q2.push_front(0);
+        EXPECT_EQ (1, q2.front());
+        EXPECT_EQ (8, q2.back());
+        EXPECT_EQ (8UL, q2.size());
+        EXPECT_EQ (false, q2.empty());
+        EXPECT_EQ (true, q2.full());
+
+        q2.push_back(9);
+        EXPECT_EQ (1, q2.front());
+        EXPECT_EQ (8, q2.back());
+        EXPECT_EQ (8UL, q2.size());
+        EXPECT_EQ (false, q2.empty());
+        EXPECT_EQ (true, q2.full());
+    }
+
+    // iterators
+    TEST (Tdeque, iterators) {
+        deque<int, 8> q1{1, 2, 3, 4, 5, 6, 7, 8};
+        int check_it=1;
+
+        EXPECT_EQ (q1.begin().base(), q1.end().base());
+        EXPECT_NE (q1.begin().iter(), q1.end().iter());
+        EXPECT_EQ (1, *q1.begin());
+        EXPECT_EQ (true, (q1.begin() == ++q1.end()));   // loop edge iterators
+
+        for (auto it = q1.begin() ; it != q1.end() ; ++it)
+            EXPECT_EQ(*it, check_it++);
+        EXPECT_EQ(9, check_it);         // run through all
+
+        EXPECT_EQ (1, q1.front());      // queue stays intact
+        EXPECT_EQ (8, q1.back());
+        EXPECT_EQ (8UL, q1.size());
+        EXPECT_EQ (false, q1.empty());
+        EXPECT_EQ (true, q1.full());
+
+        q1.pop_front();
+        q1.pop_back();
+
+        check_it=2;
+        for (auto& it : q1)
+            EXPECT_EQ(it, check_it++);
+        EXPECT_EQ(8, check_it);         // run through all
+
+        EXPECT_EQ (2, q1.front());      // queue stays intact
+        EXPECT_EQ (7, q1.back());
+        EXPECT_EQ (6UL, q1.size());
+        EXPECT_EQ (false, q1.empty());
+        EXPECT_EQ (false, q1.full());
+
+        deque<int, 8> q2;
+        q2.push_front(2);
+        q2.push_front(1);
+        q2.push_back(3);
+        q2.push_back(4);
+        q2.push_back(5);
+        check_it =1;
+        for (auto& it : q2)
+            EXPECT_EQ(it, check_it++);
+        EXPECT_EQ(6, check_it);         // run through all
+
+    }
+
+}