circular_buffer

A fixed capacity circular buffer.

STL equivalent: none

etl::circular_buffer<typename T, size_t SIZE>

etl::circular_buffer_ext<typename T>

Inherits from etl::icircular_buffer<T>

etl::icircular_buffer may be used as a size independent pointer or reference type for any etl::circular_buffer

instance.

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External buffer

etl::circular_buffer_ext<typename T>

For this template the constructor expects pointer and size parameters to the externally provided buffer. This buffer

must not be shared concurrently with any other vector.

When a circular with an external buffer is moved, the data is moved, not the pointer to the buffer.

The external buffer MUST be declared one item larger that the intended capacity of the circular buffer.

A swap on a circular buffer with an external buffer is fast as it will swap buffer pointers rather than copying items.

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Template deduction guides

C++17 and above

template <typename T, typename... Ts>

etl::circular_buffer(T, Ts...)

-> etl::circular_buffer<etl::enable_if_t<(etl::is_same_v<T, Ts> && ...), T>, 1U + sizeof...(Ts)>;

Example

etl::circular_buffer data{ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 };

Defines data as an circular_buffer of int, of length 10, containing the supplied data.

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Member types

value_type T

size_type std::size_t

difference_type std::ptrdiff_t

reference value_type&

const_reference const value_type&

rvalue_reference value_type&&

pointer value_type*

const_pointer const value_type*

iterator Random access iterator

const_iterator Constant random access iterator

reverse_iterator reverse_iterator<iterator>

const_reverse_iterator reverse_iterator<const_iterator>

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Static Constants

MAX_SIZE The maximum size of the circular_buffer.

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Constructor

circular_buffer<typename T, size_t SIZE>();

circular_buffer<typename T, size_t SIZE>(const etl::circular_buffer<typename T, size_t SIZE>& other);

circular_buffer<typename T, size_t SIZE>(etl::circular_buffer<typename T, size_t SIZE>&& other);

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circular_buffer_ext(void* buffer, size_t max_size)

circular_buffer_ext(size_t max_size) 20.32.1

template <typename TIterator>

circular_buffer_ext(TIterator first, const TIterator& last, void* buffer, size_t max_size)

circular_buffer_ext(std::initializer_list<T> init, void* buffer, size_t max_size)

circular_buffer_ext(const circular_buffer_ext& other, void* buffer, size_t max_size)

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Status

bool is_valid() const

Returns true if the buffer has been set through the constructor or set_buffer.

For circular_buffer_ext only.

20.32.1

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Element access

reference operator[](size_t i)

const_reference operator[](size_t i) const

Returns a reference or const reference to the indexed element

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reference front()

const_reference front() const

Returns a reference or const reference to the first element.

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reference back()

const_reference back() const

Returns a reference or const reference to the last element.

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void fill(value_type value)

Fill the current size of the buffer with value

20.24.0

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Iterators

iterator begin()

const_iterator begin() const

const_iterator cbegin() const

Returns an iterator to the beginning of the circular_buffer.

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iterator end()

const_iterator end() const

const_iterator cend() const

Returns an iterator to the end of the circular_buffer.

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iterator rbegin()

const_reverse_iterator rbegin() const

const_reverse_iterator crbegin() const

Returns a reverse iterator to the beginning of the circular_buffer.

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iterator rend()

const_reverse_iterator rend() const

const_reverse_iterator crend() const

Returns a reverse iterator to the end of the circular_buffer.

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Capacity

bool empty() const

Returns true if the size of the circular_buffer is zero, otherwise false.

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bool full() const

Returns true if the size of the circular_buffer is SIZE, otherwise false.

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size_t size() const

Returns the size of the circular_buffer.

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size_t max_size() const

Returns the maximum possible size of the circular_buffer.

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size_t capacity() const

Returns the maximum possible size of the circular_buffer.

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size_t available() const

Returns the remaining available capacity in the circular_buffer.

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Modifiers

void set_buffer(void* buffer)

Sets the associated buffer.

For circular_buffer_ext only.

20.32.1

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void push(const_reference value)

void push(rvalue_reference value)

Pushes a value to the back of the circular_buffer.

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template <typename TIterator>

void push(TIterator first, const TIterator& last)

Pushes values to the back of the circular_buffer.

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void pop()

Pop a value from the front of the circular_buffer.

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void clear()

Clears the circular_buffer to a size of zero.

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void swap(circular_buffer<T, SIZE>& other)

Swaps the circular_buffer with other.

void swap(circular_buffer_ext<T> other)

Swaps the circular_buffer_ext with other.

The internal pointers to the external buffers are swapped.

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Non-member functions

== true if the contents of the vectors are equal, otherwise false.

!= true if the contents of the vectors are not equal, otherwise false.

swap Swaps two circular buffers. A circular buffer with internal storage copies items while one with an external buffer

will swap pointers.

circular_buffer.h