Stefan Scholz
Containers (STL-compatible) StateMachines MessageBus and more for Embedded Systems. See www.etlcpp.com
Diff: cyclic_value.h
- Revision:
- 0:b47c2a7920c2
diff -r 000000000000 -r b47c2a7920c2 cyclic_value.h
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/cyclic_value.h Fri Mar 16 16:34:18 2018 +0000
@@ -0,0 +1,582 @@
+///\file
+
+/******************************************************************************
+The MIT License(MIT)
+
+Embedded Template Library.
+https://github.com/ETLCPP/etl
+http://www.etlcpp.com
+
+Copyright(c) 2014 jwellbelove
+
+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.
+******************************************************************************/
+
+#ifndef __ETL_CYCLIC_VALUE__
+#define __ETL_CYCLIC_VALUE__
+
+#include <stddef.h>
+
+///\defgroup cyclic_value cyclic_value
+/// Provides a value that cycles between two limits.
+/// \ingroup utilities
+
+#include <algorithm>
+
+#include "platform.h"
+#include "static_assert.h"
+#include "exception.h"
+#include "static_assert.h"
+#include "type_traits.h"
+
+namespace etl
+{
+ //***************************************************************************
+ /// Provides a value that cycles between two limits.
+ /// Supports incrementing and decrementing.
+ ///\tparam T The type of the variable.
+ ///\tparam FIRST The first value of the range.
+ ///\tparam LAST The last value of the range.
+ ///\ingroup cyclic_value
+ //***************************************************************************
+ template <typename T, T FIRST = 0, T LAST = 0, typename = void>
+ class cyclic_value
+ {
+ public:
+
+ //*************************************************************************
+ /// Constructor.
+ /// The initial value is set to the first value.
+ //*************************************************************************
+ cyclic_value()
+ : value(FIRST)
+ {
+ }
+
+ //*************************************************************************
+ /// Copy constructor.
+ //*************************************************************************
+ cyclic_value(const cyclic_value<T, FIRST, LAST>& other)
+ : value(other.value)
+ {
+ }
+
+ //*************************************************************************
+ /// Sets the value.
+ ///\param value The value.
+ //*************************************************************************
+ void set(T value_)
+ {
+ if (value_ > LAST)
+ {
+ value_ = LAST;
+ }
+ else if (value_ < FIRST)
+ {
+ value_ = FIRST;
+ }
+
+ value = value_;
+ }
+
+ //*************************************************************************
+ /// Resets the value to the first in the range.
+ //*************************************************************************
+ void to_first()
+ {
+ value = FIRST;
+ }
+
+ //*************************************************************************
+ /// Resets the value to the last in the range.
+ //*************************************************************************
+ void to_last()
+ {
+ value = LAST;
+ }
+
+ //*************************************************************************
+ /// Advances to value by a number of steps.
+ ///\param n The number of steps to advance.
+ //*************************************************************************
+ void advance(int n)
+ {
+ T range = LAST - FIRST + T(1);
+
+ n = n % range;
+
+ if (n > 0)
+ {
+ for (int i = 0; i < n; ++i)
+ {
+ operator ++();
+ }
+ }
+ else
+ {
+ for (int i = 0; i < -n; ++i)
+ {
+ operator --();
+ }
+ }
+ }
+
+ //*************************************************************************
+ /// Conversion operator.
+ /// \return The value of the underlying type.
+ //*************************************************************************
+ operator T()
+ {
+ return value;
+ }
+
+ //*************************************************************************
+ /// Const conversion operator.
+ /// \return The value of the underlying type.
+ //*************************************************************************
+ operator const T() const
+ {
+ return value;
+ }
+
+ //*************************************************************************
+ /// ++ operator.
+ //*************************************************************************
+ cyclic_value& operator ++()
+ {
+ if (value >= LAST)
+ {
+ value = FIRST;
+ }
+ else
+ {
+ ++value;
+ }
+
+ return *this;
+ }
+
+ //*************************************************************************
+ /// ++ operator.
+ //*************************************************************************
+ cyclic_value operator ++(int)
+ {
+ cyclic_value temp(*this);
+
+ operator++();
+
+ return temp;
+ }
+
+ //*************************************************************************
+ /// -- operator.
+ //*************************************************************************
+ cyclic_value& operator --()
+ {
+ if (value <= FIRST)
+ {
+ value = LAST;
+ }
+ else
+ {
+ --value;
+ }
+
+ return *this;
+ }
+
+ //*************************************************************************
+ /// -- operator.
+ //*************************************************************************
+ cyclic_value operator --(int)
+ {
+ cyclic_value temp(*this);
+
+ operator--();
+
+ return temp;
+ }
+
+ //*************************************************************************
+ /// = operator.
+ //*************************************************************************
+ cyclic_value& operator =(T t)
+ {
+ set(t);
+ return *this;
+ }
+
+ //*************************************************************************
+ /// = operator.
+ //*************************************************************************
+ template <const T FIRST2, const T LAST2>
+ cyclic_value& operator =(const cyclic_value<T, FIRST2, LAST2>& other)
+ {
+ set(other.get());
+ return *this;
+ }
+
+ //*************************************************************************
+ /// Gets the value.
+ //*************************************************************************
+ T get() const
+ {
+ return value;
+ }
+
+ //*************************************************************************
+ /// Gets the first value.
+ //*************************************************************************
+ const T first() const
+ {
+ return FIRST;
+ }
+
+ //*************************************************************************
+ /// Gets the last value.
+ //*************************************************************************
+ const T last() const
+ {
+ return LAST;
+ }
+
+ //*************************************************************************
+ /// Swaps the values.
+ //*************************************************************************
+ void swap(cyclic_value<T, FIRST, LAST>& other)
+ {
+ std::swap(value, other.value);
+ }
+
+ //*************************************************************************
+ /// Swaps the values.
+ //*************************************************************************
+ friend void swap(cyclic_value<T, FIRST, LAST>& lhs, cyclic_value<T, FIRST, LAST>& rhs)
+ {
+ lhs.swap(rhs);
+ }
+
+ //*************************************************************************
+ /// Operator ==.
+ //*************************************************************************
+ friend bool operator == (const cyclic_value<T, FIRST, LAST>& lhs, const cyclic_value<T, FIRST, LAST>& rhs)
+ {
+ return lhs.value == rhs.value;
+ }
+
+ //*************************************************************************
+ /// Operator !=.
+ //*************************************************************************
+ friend bool operator != (const cyclic_value<T, FIRST, LAST>& lhs, const cyclic_value<T, FIRST, LAST>& rhs)
+ {
+ return !(lhs == rhs);
+ }
+
+ private:
+
+ T value; ///< The current value.
+ };
+
+ //***************************************************************************
+ /// Provides a value that cycles between two limits.
+ /// Supports incrementing and decrementing.
+ ///\tparam T The type of the variable.
+ ///\tparam FIRST The first value of the range.
+ ///\tparam LAST The last value of the range.
+ ///\ingroup cyclic_value
+ //***************************************************************************
+ template <typename T, const T FIRST, const T LAST>
+ class cyclic_value<T, FIRST, LAST, typename etl::enable_if<(FIRST == 0) && (LAST == 0)>::type>
+ {
+ public:
+
+ //*************************************************************************
+ /// Constructor.
+ /// Sets 'first' and 'last' to the template parameter values.
+ /// The initial value is set to the first value.
+ //*************************************************************************
+ cyclic_value()
+ : value(FIRST),
+ first_value(FIRST),
+ last_value(LAST)
+ {
+ }
+
+ //*************************************************************************
+ /// Constructor.
+ /// Sets the value to the first of the range.
+ ///\param first The first value in the range.
+ ///\param last The last value in the range.
+ //*************************************************************************
+ cyclic_value(T first_, T last_)
+ : value(first_),
+ first_value(first_),
+ last_value(last_)
+ {
+ }
+
+ //*************************************************************************
+ /// Copy constructor.
+ //*************************************************************************
+ cyclic_value(const cyclic_value& other)
+ : value(other.value),
+ first_value(other.first_value),
+ last_value(other.last_value)
+ {
+ }
+
+ //*************************************************************************
+ /// Sets the range.
+ /// Sets the value to the first of the range.
+ ///\param first The first value in the range.
+ ///\param last The last value in the range.
+ //*************************************************************************
+ void set(T first_, T last_)
+ {
+ first_value = first_;
+ last_value = last_;
+ value = first_;
+ }
+
+ //*************************************************************************
+ /// Sets the value.
+ ///\param value The value.
+ //*************************************************************************
+ void set(T value_)
+ {
+ if (value_ > last_value)
+ {
+ value_ = last_value;
+ }
+ else if (value_ < first_value)
+ {
+ value_ = first_value;
+ }
+
+ value = value_;
+ }
+
+ //*************************************************************************
+ /// Resets the value to the first in the range.
+ //*************************************************************************
+ void to_first()
+ {
+ value = first_value;
+ }
+
+ //*************************************************************************
+ /// Resets the value to the last in the range.
+ //*************************************************************************
+ void to_last()
+ {
+ value = last_value;
+ }
+
+ //*************************************************************************
+ /// Advances to value by a number of steps.
+ ///\param n The number of steps to advance.
+ //*************************************************************************
+ void advance(int n)
+ {
+ T range = last_value - first_value + T(1);
+
+ n = n % range;
+
+ if (n > 0)
+ {
+ for (int i = 0; i < n; ++i)
+ {
+ operator ++();
+ }
+ }
+ else
+ {
+ for (int i = 0; i < -n; ++i)
+ {
+ operator --();
+ }
+ }
+ }
+
+ //*************************************************************************
+ /// Conversion operator.
+ /// \return The value of the underlying type.
+ //*************************************************************************
+ operator T()
+ {
+ return value;
+ }
+
+ //*************************************************************************
+ /// Const conversion operator.
+ /// \return The value of the underlying type.
+ //*************************************************************************
+ operator const T() const
+ {
+ return value;
+ }
+
+ //*************************************************************************
+ /// ++ operator.
+ //*************************************************************************
+ cyclic_value& operator ++()
+ {
+ if (value >= last_value)
+ {
+ value = first_value;
+ }
+ else
+ {
+ ++value;
+ }
+
+ return *this;
+ }
+
+ //*************************************************************************
+ /// ++ operator.
+ //*************************************************************************
+ cyclic_value operator ++(int)
+ {
+ cyclic_value temp(*this);
+
+ operator++();
+
+ return temp;
+ }
+
+ //*************************************************************************
+ /// -- operator.
+ //*************************************************************************
+ cyclic_value& operator --()
+ {
+ if (value <= first_value)
+ {
+ value = last_value;
+ }
+ else
+ {
+ --value;
+ }
+
+ return *this;
+ }
+
+ //*************************************************************************
+ /// -- operator.
+ //*************************************************************************
+ cyclic_value operator --(int)
+ {
+ cyclic_value temp(*this);
+
+ operator--();
+
+ return temp;
+ }
+
+ //*************************************************************************
+ /// = operator.
+ //*************************************************************************
+ cyclic_value& operator =(T t)
+ {
+ set(t);
+ return *this;
+ }
+
+ //*************************************************************************
+ /// = operator.
+ //*************************************************************************
+ cyclic_value& operator =(const cyclic_value& other)
+ {
+ value = other.value;
+ first_value = other.first_value;
+ last_value = other.last_value;
+ return *this;
+ }
+
+ //*************************************************************************
+ /// Gets the value.
+ //*************************************************************************
+ T get() const
+ {
+ return value;
+ }
+
+ //*************************************************************************
+ /// Gets the first value.
+ //*************************************************************************
+ T first() const
+ {
+ return first_value;
+ }
+
+ //*************************************************************************
+ /// Gets the last value.
+ //*************************************************************************
+ T last() const
+ {
+ return last_value;
+ }
+
+ //*************************************************************************
+ /// Swaps the values.
+ //*************************************************************************
+ void swap(cyclic_value<T, FIRST, LAST>& other)
+ {
+ std::swap(first_value, other.first_value);
+ std::swap(last_value, other.last_value);
+ std::swap(value, other.value);
+ }
+
+ //*************************************************************************
+ /// Swaps the values.
+ //*************************************************************************
+ friend void swap(cyclic_value<T, FIRST, LAST>& lhs, cyclic_value<T, FIRST, LAST>& rhs)
+ {
+ lhs.swap(rhs);
+ }
+
+ //*************************************************************************
+ /// Operator ==.
+ //*************************************************************************
+ friend bool operator == (const cyclic_value<T, FIRST, LAST>& lhs, const cyclic_value<T, FIRST, LAST>& rhs)
+ {
+ return (lhs.value == rhs.value) &&
+ (lhs.first_value == rhs.first_value) &&
+ (lhs.last_value == rhs.last_value);
+ }
+
+ //*************************************************************************
+ /// Operator !=.
+ //*************************************************************************
+ friend bool operator != (const cyclic_value<T, FIRST, LAST>& lhs, const cyclic_value<T, FIRST, LAST>& rhs)
+ {
+ return !(lhs == rhs);
+ }
+
+ private:
+
+ T value; ///< The current value.
+ T first_value; ///< The first value in the range.
+ T last_value; ///< The last value in the range.
+ };
+}
+
+#endif
+