srsLTE/lib/include/srsran/adt/circular_buffer.h

601 lines
18 KiB
C++

/**
*
* \section COPYRIGHT
*
* Copyright 2013-2021 Software Radio Systems Limited
*
* By using this file, you agree to the terms and conditions set
* forth in the LICENSE file which can be found at the top level of
* the distribution.
*
*/
#ifndef SRSRAN_CIRCULAR_BUFFER_H
#define SRSRAN_CIRCULAR_BUFFER_H
#include "srsran/adt/detail/type_storage.h"
#include "srsran/adt/expected.h"
#include "srsran/adt/pool/pool_utils.h"
#include "srsran/support/srsran_assert.h"
#include <array>
#include <cassert>
#include <condition_variable>
#include <functional>
#include <mutex>
#include <thread>
#include <type_traits>
#include <vector>
namespace srsran {
namespace detail {
template <typename T, size_t N>
size_t get_max_size(const std::array<T, N>& a)
{
return a.max_size();
}
template <typename T>
size_t get_max_size(const std::vector<T>& a)
{
return a.capacity();
}
/**
* Base common class for definition of circular buffer data structures with the following features:
* - no allocations while pushing/popping new elements. Just an internal index update
* - it provides helper methods to add/remove objects
* - it provides an iterator interface to iterate over added elements in the buffer
* - not thread-safe
* @tparam Container underlying container type used as buffer (e.g. std::array<T, N> or std::vector<T>)
*/
template <typename Container>
class base_circular_buffer
{
using storage_t = typename Container::value_type;
using T = typename storage_t::value_type;
template <typename DataType>
class iterator_impl
{
using parent_type = typename std::conditional<std::is_same<DataType, T>::value,
base_circular_buffer<Container>,
const base_circular_buffer<Container> >::type;
public:
using value_type = DataType;
using reference = DataType&;
using pointer = DataType*;
using difference_type = std::ptrdiff_t;
using iterator_category = std::forward_iterator_tag;
iterator_impl(parent_type& parent_, size_t i) : parent(&parent_), idx(i) {}
iterator_impl<DataType>& operator++()
{
idx = (idx + 1) % parent->max_size();
return *this;
}
iterator_impl<DataType> operator++(int)
{
iterator_impl<DataType> tmp(*this);
++(*this);
return tmp;
}
iterator_impl<DataType> operator+(difference_type n)
{
iterator_impl<DataType> tmp(*this);
tmp += n;
return tmp;
}
iterator_impl<DataType>& operator+=(difference_type n)
{
idx = (idx + n) % parent->max_size();
return *this;
}
value_type* operator->() { return &get(); }
const value_type* operator->() const { return &get(); }
value_type& operator*() { return get(); }
const value_type& operator*() const { return get(); }
bool operator==(const iterator_impl<DataType>& it) const { return it.parent == parent and it.idx == idx; }
bool operator!=(const iterator_impl<DataType>& it) const { return not(*this == it); }
private:
void assert_idx_within_bounds()
{
srsran_assert(idx + (idx >= parent->rpos ? 0 : parent->max_size()) < parent->rpos + parent->count,
"index=%zd is out-of-bounds [%zd, %zd)",
idx,
parent->rpos,
parent->count);
}
value_type& get()
{
assert_idx_within_bounds();
return parent->buffer[idx].get();
}
const value_type& get() const
{
assert_idx_within_bounds();
return parent->buffer[idx].get();
}
parent_type* parent;
size_t idx;
};
public:
using value_type = T;
using difference_type = typename Container::difference_type;
using size_type = std::size_t;
using iterator = iterator_impl<T>;
using const_iterator = iterator_impl<const T>;
base_circular_buffer() = default;
~base_circular_buffer() { clear(); }
template <typename U>
typename std::enable_if<std::is_constructible<T, U>::value>::type push(U&& t)
{
srsran_assert(not full(), "Circular buffer is full.");
size_t wpos = (rpos + count) % max_size();
buffer[wpos].emplace(std::forward<U>(t));
count++;
}
bool try_push(T&& t)
{
if (full()) {
return false;
}
push(std::move(t));
return true;
}
bool try_push(const T& t)
{
if (full()) {
return false;
}
push(t);
return true;
}
void pop()
{
srsran_assert(not empty(), "Cannot call pop() in empty circular buffer");
buffer[rpos].destroy();
rpos = (rpos + 1) % max_size();
count--;
}
T& top()
{
srsran_assert(not empty(), "Cannot call top() in empty circular buffer");
return buffer[rpos].get();
}
const T& top() const
{
srsran_assert(not empty(), "Cannot call top() in empty circular buffer");
return buffer[rpos].get();
}
void clear()
{
for (size_t i = 0; i < count; ++i) {
buffer[(rpos + i) % max_size()].destroy();
}
count = 0;
}
bool full() const { return count == max_size(); }
bool empty() const { return count == 0; }
size_t size() const { return count; }
size_t max_size() const { return detail::get_max_size(buffer); }
T& operator[](size_t i)
{
srsran_assert(i < count, "Out-of-bounds access to circular buffer (%zd >= %zd)", i, count);
return buffer[(rpos + i) % max_size()].get();
}
const T& operator[](size_t i) const
{
srsran_assert(i < count, "Out-of-bounds access to circular buffer (%zd >= %zd)", i, count);
return buffer[(rpos + i) % max_size()].get();
}
iterator begin() { return iterator(*this, rpos); }
const_iterator begin() const { return const_iterator(*this, rpos); }
iterator end() { return iterator(*this, (rpos + count) % max_size()); }
const_iterator end() const { return const_iterator(*this, (rpos + count) % max_size()); }
template <typename F>
bool apply_first(const F& func)
{
for (auto it = begin(); it != end(); it++) {
if (func(*it)) {
return true;
}
}
return false;
}
protected:
base_circular_buffer(size_t rpos_, size_t count_) : rpos(rpos_), count(count_) {}
template <typename... BufferArgs>
base_circular_buffer(size_t rpos_, size_t count_, BufferArgs&&... args) :
rpos(rpos_), count(count_), buffer(std::forward<BufferArgs>(args)...)
{}
Container buffer;
size_t rpos = 0;
size_t count = 0;
};
/**
* Base common class for definition of blocking queue data structures with the following features:
* - it stores pushed/popped samples in an internal circular buffer
* - provides blocking and non-blocking push/pop APIs
* - thread-safe
* @tparam CircBuffer underlying circular buffer data type (e.g. static_circular_buffer<T, N> or dyn_circular_buffer<T>)
* @tparam PushingFunc function void(const T&) called while pushing an element to the queue
* @tparam PoppingFunc function void(const T&) called while popping an element from the queue
*/
template <typename CircBuffer, typename PushingFunc, typename PoppingFunc>
class base_blocking_queue
{
using T = typename CircBuffer::value_type;
public:
template <typename... Args>
base_blocking_queue(PushingFunc push_func_, PoppingFunc pop_func_, Args&&... args) :
circ_buffer(std::forward<Args>(args)...), push_func(push_func_), pop_func(pop_func_)
{}
base_blocking_queue(const base_blocking_queue&) = delete;
base_blocking_queue(base_blocking_queue&&) = delete;
base_blocking_queue& operator=(const base_blocking_queue&) = delete;
base_blocking_queue& operator=(base_blocking_queue&&) = delete;
void stop()
{
std::unique_lock<std::mutex> lock(mutex);
if (active) {
active = false;
if (nof_waiting > 0) {
// Stop pending pushing/popping threads
do {
lock.unlock();
cvar_empty.notify_all();
cvar_full.notify_all();
std::this_thread::yield();
lock.lock();
} while (nof_waiting > 0);
}
// Empty queue
circ_buffer.clear();
}
}
bool try_push(const T& t) { return push_(t, false); }
srsran::error_type<T> try_push(T&& t) { return push_(std::move(t), false); }
bool push_blocking(const T& t) { return push_(t, true); }
srsran::error_type<T> push_blocking(T&& t) { return push_(std::move(t), true); }
bool try_pop(T& obj) { return pop_(obj, false); }
T pop_blocking(bool* success = nullptr)
{
T obj{};
bool ret = pop_(obj, true);
if (success != nullptr) {
*success = ret;
}
return obj;
}
bool pop_wait_until(T& obj, const std::chrono::system_clock::time_point& until) { return pop_(obj, true, &until); }
void clear()
{
T obj;
while (pop_(obj, false)) {
}
}
size_t size() const
{
std::lock_guard<std::mutex> lock(mutex);
return circ_buffer.size();
}
bool empty() const
{
std::lock_guard<std::mutex> lock(mutex);
return circ_buffer.empty();
}
bool full() const
{
std::lock_guard<std::mutex> lock(mutex);
return circ_buffer.full();
}
size_t max_size() const
{
std::lock_guard<std::mutex> lock(mutex);
return circ_buffer.max_size();
}
bool is_stopped() const
{
std::lock_guard<std::mutex> lock(mutex);
return not active;
}
template <typename F>
bool try_call_on_front(F&& f)
{
std::lock_guard<std::mutex> lock(mutex);
if (not circ_buffer.empty()) {
f(circ_buffer.top());
return true;
}
return false;
}
template <typename F>
bool apply_first(const F& func)
{
std::lock_guard<std::mutex> lock(mutex);
return circ_buffer.apply_first(func);
}
PushingFunc push_func;
PoppingFunc pop_func;
protected:
bool active = true;
uint8_t nof_waiting = 0;
mutable std::mutex mutex;
std::condition_variable cvar_empty, cvar_full;
CircBuffer circ_buffer;
~base_blocking_queue() { stop(); }
bool push_(const T& t, bool block_mode)
{
std::unique_lock<std::mutex> lock(mutex);
if (not active) {
return false;
}
if (circ_buffer.full()) {
if (not block_mode) {
return false;
}
nof_waiting++;
while (circ_buffer.full() and active) {
cvar_full.wait(lock);
}
nof_waiting--;
if (not active) {
return false;
}
}
push_func(t);
circ_buffer.push(t);
lock.unlock();
cvar_empty.notify_one();
return true;
}
srsran::error_type<T> push_(T&& t, bool block_mode)
{
std::unique_lock<std::mutex> lock(mutex);
if (not active) {
return std::move(t);
}
if (circ_buffer.full()) {
if (not block_mode) {
return std::move(t);
}
nof_waiting++;
while (circ_buffer.full() and active) {
cvar_full.wait(lock);
}
nof_waiting--;
if (not active) {
return std::move(t);
}
}
push_func(t);
circ_buffer.push(std::move(t));
lock.unlock();
cvar_empty.notify_one();
return {};
}
bool pop_(T& obj, bool block, const std::chrono::system_clock::time_point* until = nullptr)
{
std::unique_lock<std::mutex> lock(mutex);
if (not active) {
return false;
}
if (circ_buffer.empty()) {
if (not block) {
return false;
}
nof_waiting++;
if (until == nullptr) {
cvar_empty.wait(lock, [this]() { return not circ_buffer.empty() or not active; });
} else {
cvar_empty.wait_until(lock, *until, [this]() { return not circ_buffer.empty() or not active; });
}
nof_waiting--;
if (circ_buffer.empty()) {
// either queue got deactivated or there was a timeout
return false;
}
}
obj = std::move(circ_buffer.top());
pop_func(obj);
circ_buffer.pop();
lock.unlock();
cvar_full.notify_one();
return true;
}
};
} // namespace detail
/**
* Circular buffer with fixed, embedded buffer storage via a std::array<T, N>.
* - Single allocation at object creation for std::array. Given that the buffer size is known at compile-time, the
* circular iteration over the buffer may be more optimized (e.g. when N is a power of 2, % operator can be avoided)
* - not thread-safe
* @tparam T value type stored by buffer
* @tparam N size of the queue
*/
template <typename T, size_t N>
class static_circular_buffer : public detail::base_circular_buffer<std::array<detail::type_storage<T>, N> >
{
using base_t = detail::base_circular_buffer<std::array<detail::type_storage<T>, N> >;
public:
static_circular_buffer() = default;
static_circular_buffer(const static_circular_buffer& other) : base_t(other.rpos, other.count)
{
static_assert(std::is_copy_constructible<T>::value, "T must be copy-constructible");
std::uninitialized_copy(other.begin(), other.end(), base_t::begin());
}
static_circular_buffer(static_circular_buffer<T, N>&& other) noexcept : base_t(other.rpos, other.count)
{
static_assert(std::is_move_constructible<T>::value, "T must be move-constructible");
for (size_t i = 0; i < other.count; ++i) {
size_t idx = (other.rpos + i) % other.max_size();
base_t::buffer[idx].move_ctor(std::move(other.buffer[idx]));
}
other.clear();
}
static_circular_buffer& operator=(const static_circular_buffer& other)
{
if (this == &other) {
return *this;
}
base_t::clear();
base_t::rpos = other.rpos;
base_t::count = other.count;
for (size_t i = 0; i < other.count; ++i) {
size_t idx = (other.rpos + i) % other.max_size();
base_t::buffer[idx].copy_ctor(other.buffer[idx]);
}
return *this;
}
static_circular_buffer& operator=(static_circular_buffer&& other) noexcept
{
base_t::clear();
base_t::rpos = other.rpos;
base_t::count = other.count;
for (size_t i = 0; i < other.count; ++i) {
size_t idx = (other.rpos + i) % other.max_size();
base_t::buffer[idx].move_ctor(std::move(other.buffer[idx]));
}
other.clear();
return *this;
}
};
/**
* Circular buffer with buffer storage via a std::vector<T>.
* - size can be defined at run-time.
* - not thread-safe
* @tparam T value type stored by buffer
*/
template <typename T>
class dyn_circular_buffer : public detail::base_circular_buffer<std::vector<detail::type_storage<T> > >
{
using base_t = detail::base_circular_buffer<std::vector<detail::type_storage<T> > >;
public:
dyn_circular_buffer() = default;
explicit dyn_circular_buffer(size_t max_size) : base_t(0, 0, max_size) {}
dyn_circular_buffer(dyn_circular_buffer&& other) noexcept : base_t(other.rpos, other.count, std::move(other.buffer))
{
other.count = 0;
other.rpos = 0;
}
dyn_circular_buffer(const dyn_circular_buffer& other) : base_t(other.rpos, other.count, other.max_size())
{
static_assert(std::is_copy_constructible<T>::value, "T must be copy-constructible");
for (size_t i = 0; i < other.count; ++i) {
size_t idx = (other.rpos + i) % other.max_size();
base_t::buffer[idx].copy_ctor(other.buffer[idx]);
}
}
dyn_circular_buffer& operator=(dyn_circular_buffer other) noexcept
{
swap(other);
other.clear();
return *this;
}
void swap(dyn_circular_buffer& other) noexcept
{
std::swap(base_t::rpos, other.rpos);
std::swap(base_t::count, other.count);
std::swap(base_t::buffer, other.buffer);
}
void set_size(size_t sz)
{
srsran_assert(base_t::empty() or sz == base_t::size(),
"Dynamic resizes not supported when circular buffer is not empty");
base_t::buffer.resize(sz);
}
};
/**
* Blocking queue with fixed, embedded buffer storage via a std::array<T, N>.
* - Blocking push/pop API via push_blocking(...) and pop_blocking(...) methods
* - Non-blocking push/pop API via try_push(...) and try_pop(...) methods
* - Only one initial allocation for the std::array<T, N>
* - thread-safe
* @tparam T value type stored by buffer
* @tparam N size of queue
* @tparam PushingCallback function void(const T&) called while pushing an element to the queue
* @tparam PoppingCallback function void(const T&) called while popping an element from the queue
*/
template <typename T,
size_t N,
typename PushingCallback = detail::noop_operator,
typename PoppingCallback = detail::noop_operator>
class static_blocking_queue
: public detail::base_blocking_queue<static_circular_buffer<T, N>, PushingCallback, PoppingCallback>
{
using base_t = detail::base_blocking_queue<static_circular_buffer<T, N>, PushingCallback, PoppingCallback>;
public:
explicit static_blocking_queue(PushingCallback push_callback = {}, PoppingCallback pop_callback = {}) :
base_t(push_callback, pop_callback)
{}
};
/**
* Blocking queue with buffer storage represented via a std::vector<T>. Features:
* - Blocking push/pop API via push_blocking(...) and pop_blocking(...) methods
* - Non-blocking push/pop API via try_push(...) and try_pop(...) methods
* - Size can be defined at runtime.
* - thread-safe
* @tparam T value type stored by buffer
* @tparam PushingCallback function void(const T&) called while pushing an element to the queue
* @tparam PoppingCallback function void(const T&) called while popping an element from the queue
*/
template <typename T,
typename PushingCallback = detail::noop_operator,
typename PoppingCallback = detail::noop_operator>
class dyn_blocking_queue : public detail::base_blocking_queue<dyn_circular_buffer<T>, PushingCallback, PoppingCallback>
{
using base_t = detail::base_blocking_queue<dyn_circular_buffer<T>, PushingCallback, PoppingCallback>;
public:
dyn_blocking_queue() = default;
explicit dyn_blocking_queue(size_t size, PushingCallback push_callback = {}, PoppingCallback pop_callback = {}) :
base_t(push_callback, pop_callback, size)
{}
void set_size(size_t size) { base_t::circ_buffer.set_size(size); }
};
} // namespace srsran
#endif // SRSRAN_CIRCULAR_BUFFER_H