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// Provides an efficient blocking version of moodycamel::ConcurrentQueue. |
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// ©2015-2020 Cameron Desrochers. Distributed under the terms of the simplified |
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// BSD license, available at the top of concurrentqueue.h. |
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// Also dual-licensed under the Boost Software License (see LICENSE.md) |
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// Uses Jeff Preshing's semaphore implementation (under the terms of its |
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// separate zlib license, see lightweightsemaphore.h). |
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#pragma once |
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#include "concurrentqueue.h" |
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#include "lightweightsemaphore.h" |
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#include <type_traits> |
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#include <cerrno> |
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#include <memory> |
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#include <chrono> |
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#include <ctime> |
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namespace moodycamel |
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{ |
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// This is a blocking version of the queue. It has an almost identical interface to |
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// the normal non-blocking version, with the addition of various wait_dequeue() methods |
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// and the removal of producer-specific dequeue methods. |
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template<typename T, typename Traits = ConcurrentQueueDefaultTraits> |
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class BlockingConcurrentQueue |
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{ |
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private: |
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typedef ::moodycamel::ConcurrentQueue<T, Traits> ConcurrentQueue; |
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typedef ::moodycamel::LightweightSemaphore LightweightSemaphore; |
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public: |
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typedef typename ConcurrentQueue::producer_token_t producer_token_t; |
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typedef typename ConcurrentQueue::consumer_token_t consumer_token_t; |
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typedef typename ConcurrentQueue::index_t index_t; |
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typedef typename ConcurrentQueue::size_t size_t; |
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typedef typename std::make_signed<size_t>::type ssize_t; |
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static const size_t BLOCK_SIZE = ConcurrentQueue::BLOCK_SIZE; |
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static const size_t EXPLICIT_BLOCK_EMPTY_COUNTER_THRESHOLD = ConcurrentQueue::EXPLICIT_BLOCK_EMPTY_COUNTER_THRESHOLD; |
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static const size_t EXPLICIT_INITIAL_INDEX_SIZE = ConcurrentQueue::EXPLICIT_INITIAL_INDEX_SIZE; |
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static const size_t IMPLICIT_INITIAL_INDEX_SIZE = ConcurrentQueue::IMPLICIT_INITIAL_INDEX_SIZE; |
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static const size_t INITIAL_IMPLICIT_PRODUCER_HASH_SIZE = ConcurrentQueue::INITIAL_IMPLICIT_PRODUCER_HASH_SIZE; |
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static const std::uint32_t EXPLICIT_CONSUMER_CONSUMPTION_QUOTA_BEFORE_ROTATE = ConcurrentQueue::EXPLICIT_CONSUMER_CONSUMPTION_QUOTA_BEFORE_ROTATE; |
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static const size_t MAX_SUBQUEUE_SIZE = ConcurrentQueue::MAX_SUBQUEUE_SIZE; |
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public: |
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// Creates a queue with at least `capacity` element slots; note that the |
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// actual number of elements that can be inserted without additional memory |
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// allocation depends on the number of producers and the block size (e.g. if |
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// the block size is equal to `capacity`, only a single block will be allocated |
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// up-front, which means only a single producer will be able to enqueue elements |
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// without an extra allocation -- blocks aren't shared between producers). |
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// This method is not thread safe -- it is up to the user to ensure that the |
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// queue is fully constructed before it starts being used by other threads (this |
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// includes making the memory effects of construction visible, possibly with a |
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// memory barrier). |
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explicit BlockingConcurrentQueue(size_t capacity = 6 * BLOCK_SIZE) |
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: inner(capacity), sema(create<LightweightSemaphore, ssize_t, int>(0, (int)Traits::MAX_SEMA_SPINS), &BlockingConcurrentQueue::template destroy<LightweightSemaphore>) |
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{ |
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assert(reinterpret_cast<ConcurrentQueue*>((BlockingConcurrentQueue*)1) == &((BlockingConcurrentQueue*)1)->inner && "BlockingConcurrentQueue must have ConcurrentQueue as its first member"); |
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if (!sema) { |
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MOODYCAMEL_THROW(std::bad_alloc()); |
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} |
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} |
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BlockingConcurrentQueue(size_t minCapacity, size_t maxExplicitProducers, size_t maxImplicitProducers) |
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: inner(minCapacity, maxExplicitProducers, maxImplicitProducers), sema(create<LightweightSemaphore, ssize_t, int>(0, (int)Traits::MAX_SEMA_SPINS), &BlockingConcurrentQueue::template destroy<LightweightSemaphore>) |
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{ |
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assert(reinterpret_cast<ConcurrentQueue*>((BlockingConcurrentQueue*)1) == &((BlockingConcurrentQueue*)1)->inner && "BlockingConcurrentQueue must have ConcurrentQueue as its first member"); |
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if (!sema) { |
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MOODYCAMEL_THROW(std::bad_alloc()); |
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} |
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} |
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// Disable copying and copy assignment |
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BlockingConcurrentQueue(BlockingConcurrentQueue const&) MOODYCAMEL_DELETE_FUNCTION; |
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BlockingConcurrentQueue& operator=(BlockingConcurrentQueue const&) MOODYCAMEL_DELETE_FUNCTION; |
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// Moving is supported, but note that it is *not* a thread-safe operation. |
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// Nobody can use the queue while it's being moved, and the memory effects |
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// of that move must be propagated to other threads before they can use it. |
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// Note: When a queue is moved, its tokens are still valid but can only be |
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// used with the destination queue (i.e. semantically they are moved along |
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// with the queue itself). |
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BlockingConcurrentQueue(BlockingConcurrentQueue&& other) MOODYCAMEL_NOEXCEPT |
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: inner(std::move(other.inner)), sema(std::move(other.sema)) |
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{ } |
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inline BlockingConcurrentQueue& operator=(BlockingConcurrentQueue&& other) MOODYCAMEL_NOEXCEPT |
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{ |
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return swap_internal(other); |
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} |
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// Swaps this queue's state with the other's. Not thread-safe. |
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// Swapping two queues does not invalidate their tokens, however |
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// the tokens that were created for one queue must be used with |
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// only the swapped queue (i.e. the tokens are tied to the |
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// queue's movable state, not the object itself). |
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inline void swap(BlockingConcurrentQueue& other) MOODYCAMEL_NOEXCEPT |
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{ |
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swap_internal(other); |
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} |
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private: |
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BlockingConcurrentQueue& swap_internal(BlockingConcurrentQueue& other) |
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{ |
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if (this == &other) { |
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return *this; |
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} |
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inner.swap(other.inner); |
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sema.swap(other.sema); |
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return *this; |
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} |
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public: |
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// Enqueues a single item (by copying it). |
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// Allocates memory if required. Only fails if memory allocation fails (or implicit |
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// production is disabled because Traits::INITIAL_IMPLICIT_PRODUCER_HASH_SIZE is 0, |
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// or Traits::MAX_SUBQUEUE_SIZE has been defined and would be surpassed). |
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// Thread-safe. |
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inline bool enqueue(T const& item) |
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{ |
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if ((details::likely)(inner.enqueue(item))) { |
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sema->signal(); |
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return true; |
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} |
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return false; |
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} |
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// Enqueues a single item (by moving it, if possible). |
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// Allocates memory if required. Only fails if memory allocation fails (or implicit |
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// production is disabled because Traits::INITIAL_IMPLICIT_PRODUCER_HASH_SIZE is 0, |
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// or Traits::MAX_SUBQUEUE_SIZE has been defined and would be surpassed). |
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// Thread-safe. |
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inline bool enqueue(T&& item) |
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{ |
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if ((details::likely)(inner.enqueue(std::move(item)))) { |
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sema->signal(); |
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return true; |
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} |
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return false; |
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} |
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// Enqueues a single item (by copying it) using an explicit producer token. |
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// Allocates memory if required. Only fails if memory allocation fails (or |
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// Traits::MAX_SUBQUEUE_SIZE has been defined and would be surpassed). |
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// Thread-safe. |
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inline bool enqueue(producer_token_t const& token, T const& item) |
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{ |
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if ((details::likely)(inner.enqueue(token, item))) { |
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sema->signal(); |
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return true; |
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} |
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return false; |
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} |
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// Enqueues a single item (by moving it, if possible) using an explicit producer token. |
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// Allocates memory if required. Only fails if memory allocation fails (or |
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// Traits::MAX_SUBQUEUE_SIZE has been defined and would be surpassed). |
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// Thread-safe. |
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inline bool enqueue(producer_token_t const& token, T&& item) |
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{ |
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if ((details::likely)(inner.enqueue(token, std::move(item)))) { |
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sema->signal(); |
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return true; |
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} |
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return false; |
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} |
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// Enqueues several items. |
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// Allocates memory if required. Only fails if memory allocation fails (or |
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// implicit production is disabled because Traits::INITIAL_IMPLICIT_PRODUCER_HASH_SIZE |
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// is 0, or Traits::MAX_SUBQUEUE_SIZE has been defined and would be surpassed). |
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// Note: Use std::make_move_iterator if the elements should be moved instead of copied. |
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// Thread-safe. |
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template<typename It> |
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inline bool enqueue_bulk(It itemFirst, size_t count) |
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{ |
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if ((details::likely)(inner.enqueue_bulk(std::forward<It>(itemFirst), count))) { |
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sema->signal((LightweightSemaphore::ssize_t)(ssize_t)count); |
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return true; |
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} |
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return false; |
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} |
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// Enqueues several items using an explicit producer token. |
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// Allocates memory if required. Only fails if memory allocation fails |
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// (or Traits::MAX_SUBQUEUE_SIZE has been defined and would be surpassed). |
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// Note: Use std::make_move_iterator if the elements should be moved |
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// instead of copied. |
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// Thread-safe. |
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template<typename It> |
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inline bool enqueue_bulk(producer_token_t const& token, It itemFirst, size_t count) |
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{ |
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if ((details::likely)(inner.enqueue_bulk(token, std::forward<It>(itemFirst), count))) { |
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sema->signal((LightweightSemaphore::ssize_t)(ssize_t)count); |
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return true; |
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} |
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return false; |
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} |
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// Enqueues a single item (by copying it). |
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// Does not allocate memory. Fails if not enough room to enqueue (or implicit |
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// production is disabled because Traits::INITIAL_IMPLICIT_PRODUCER_HASH_SIZE |
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// is 0). |
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// Thread-safe. |
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inline bool try_enqueue(T const& item) |
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{ |
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if (inner.try_enqueue(item)) { |
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sema->signal(); |
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return true; |
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} |
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return false; |
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} |
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// Enqueues a single item (by moving it, if possible). |
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// Does not allocate memory (except for one-time implicit producer). |
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// Fails if not enough room to enqueue (or implicit production is |
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// disabled because Traits::INITIAL_IMPLICIT_PRODUCER_HASH_SIZE is 0). |
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// Thread-safe. |
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inline bool try_enqueue(T&& item) |
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{ |
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if (inner.try_enqueue(std::move(item))) { |
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sema->signal(); |
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return true; |
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} |
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return false; |
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} |
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// Enqueues a single item (by copying it) using an explicit producer token. |
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// Does not allocate memory. Fails if not enough room to enqueue. |
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// Thread-safe. |
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inline bool try_enqueue(producer_token_t const& token, T const& item) |
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{ |
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if (inner.try_enqueue(token, item)) { |
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sema->signal(); |
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return true; |
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} |
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return false; |
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} |
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// Enqueues a single item (by moving it, if possible) using an explicit producer token. |
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// Does not allocate memory. Fails if not enough room to enqueue. |
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// Thread-safe. |
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inline bool try_enqueue(producer_token_t const& token, T&& item) |
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{ |
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if (inner.try_enqueue(token, std::move(item))) { |
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sema->signal(); |
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return true; |
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} |
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return false; |
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} |
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// Enqueues several items. |
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// Does not allocate memory (except for one-time implicit producer). |
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// Fails if not enough room to enqueue (or implicit production is |
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// disabled because Traits::INITIAL_IMPLICIT_PRODUCER_HASH_SIZE is 0). |
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// Note: Use std::make_move_iterator if the elements should be moved |
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// instead of copied. |
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// Thread-safe. |
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template<typename It> |
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inline bool try_enqueue_bulk(It itemFirst, size_t count) |
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{ |
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if (inner.try_enqueue_bulk(std::forward<It>(itemFirst), count)) { |
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sema->signal((LightweightSemaphore::ssize_t)(ssize_t)count); |
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return true; |
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} |
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return false; |
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} |
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// Enqueues several items using an explicit producer token. |
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// Does not allocate memory. Fails if not enough room to enqueue. |
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// Note: Use std::make_move_iterator if the elements should be moved |
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// instead of copied. |
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// Thread-safe. |
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template<typename It> |
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inline bool try_enqueue_bulk(producer_token_t const& token, It itemFirst, size_t count) |
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{ |
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if (inner.try_enqueue_bulk(token, std::forward<It>(itemFirst), count)) { |
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sema->signal((LightweightSemaphore::ssize_t)(ssize_t)count); |
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return true; |
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} |
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return false; |
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} |
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// Attempts to dequeue from the queue. |
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// Returns false if all producer streams appeared empty at the time they |
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// were checked (so, the queue is likely but not guaranteed to be empty). |
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// Never allocates. Thread-safe. |
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template<typename U> |
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inline bool try_dequeue(U& item) |
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{ |
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if (sema->tryWait()) { |
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while (!inner.try_dequeue(item)) { |
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continue; |
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} |
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return true; |
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} |
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return false; |
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} |
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// Attempts to dequeue from the queue using an explicit consumer token. |
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// Returns false if all producer streams appeared empty at the time they |
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// were checked (so, the queue is likely but not guaranteed to be empty). |
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// Never allocates. Thread-safe. |
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template<typename U> |
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inline bool try_dequeue(consumer_token_t& token, U& item) |
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{ |
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if (sema->tryWait()) { |
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while (!inner.try_dequeue(token, item)) { |
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continue; |
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} |
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return true; |
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} |
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return false; |
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} |
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// Attempts to dequeue several elements from the queue. |
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// Returns the number of items actually dequeued. |
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// Returns 0 if all producer streams appeared empty at the time they |
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// were checked (so, the queue is likely but not guaranteed to be empty). |
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// Never allocates. Thread-safe. |
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template<typename It> |
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inline size_t try_dequeue_bulk(It itemFirst, size_t max) |
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{ |
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size_t count = 0; |
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max = (size_t)sema->tryWaitMany((LightweightSemaphore::ssize_t)(ssize_t)max); |
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while (count != max) { |
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count += inner.template try_dequeue_bulk<It&>(itemFirst, max - count); |
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} |
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return count; |
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} |
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// Attempts to dequeue several elements from the queue using an explicit consumer token. |
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// Returns the number of items actually dequeued. |
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// Returns 0 if all producer streams appeared empty at the time they |
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// were checked (so, the queue is likely but not guaranteed to be empty). |
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// Never allocates. Thread-safe. |
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template<typename It> |
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inline size_t try_dequeue_bulk(consumer_token_t& token, It itemFirst, size_t max) |
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{ |
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size_t count = 0; |
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max = (size_t)sema->tryWaitMany((LightweightSemaphore::ssize_t)(ssize_t)max); |
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while (count != max) { |
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count += inner.template try_dequeue_bulk<It&>(token, itemFirst, max - count); |
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} |
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return count; |
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} |
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// Blocks the current thread until there's something to dequeue, then |
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// dequeues it. |
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// Never allocates. Thread-safe. |
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template<typename U> |
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inline void wait_dequeue(U& item) |
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{ |
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while (!sema->wait()) { |
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continue; |
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} |
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while (!inner.try_dequeue(item)) { |
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continue; |
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} |
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} |
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// Blocks the current thread until either there's something to dequeue |
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// or the timeout (specified in microseconds) expires. Returns false |
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// without setting `item` if the timeout expires, otherwise assigns |
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// to `item` and returns true. |
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// Using a negative timeout indicates an indefinite timeout, |
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// and is thus functionally equivalent to calling wait_dequeue. |
|
|
|
// Never allocates. Thread-safe. |
|
|
|
template<typename U> |
|
|
|
inline bool wait_dequeue_timed(U& item, std::int64_t timeout_usecs) |
|
|
|
{ |
|
|
|
if (!sema->wait(timeout_usecs)) { |
|
|
|
return false; |
|
|
|
} |
|
|
|
while (!inner.try_dequeue(item)) { |
|
|
|
continue; |
|
|
|
} |
|
|
|
return true; |
|
|
|
} |
|
|
|
|
|
|
|
// Blocks the current thread until either there's something to dequeue |
|
|
|
// or the timeout expires. Returns false without setting `item` if the |
|
|
|
// timeout expires, otherwise assigns to `item` and returns true. |
|
|
|
// Never allocates. Thread-safe. |
|
|
|
template<typename U, typename Rep, typename Period> |
|
|
|
inline bool wait_dequeue_timed(U& item, std::chrono::duration<Rep, Period> const& timeout) |
|
|
|
{ |
|
|
|
return wait_dequeue_timed(item, std::chrono::duration_cast<std::chrono::microseconds>(timeout).count()); |
|
|
|
} |
|
|
|
|
|
|
|
// Blocks the current thread until there's something to dequeue, then |
|
|
|
// dequeues it using an explicit consumer token. |
|
|
|
// Never allocates. Thread-safe. |
|
|
|
template<typename U> |
|
|
|
inline void wait_dequeue(consumer_token_t& token, U& item) |
|
|
|
{ |
|
|
|
while (!sema->wait()) { |
|
|
|
continue; |
|
|
|
} |
|
|
|
while (!inner.try_dequeue(token, item)) { |
|
|
|
continue; |
|
|
|
} |
|
|
|
} |
|
|
|
|
|
|
|
// Blocks the current thread until either there's something to dequeue |
|
|
|
// or the timeout (specified in microseconds) expires. Returns false |
|
|
|
// without setting `item` if the timeout expires, otherwise assigns |
|
|
|
// to `item` and returns true. |
|
|
|
// Using a negative timeout indicates an indefinite timeout, |
|
|
|
// and is thus functionally equivalent to calling wait_dequeue. |
|
|
|
// Never allocates. Thread-safe. |
|
|
|
template<typename U> |
|
|
|
inline bool wait_dequeue_timed(consumer_token_t& token, U& item, std::int64_t timeout_usecs) |
|
|
|
{ |
|
|
|
if (!sema->wait(timeout_usecs)) { |
|
|
|
return false; |
|
|
|
} |
|
|
|
while (!inner.try_dequeue(token, item)) { |
|
|
|
continue; |
|
|
|
} |
|
|
|
return true; |
|
|
|
} |
|
|
|
|
|
|
|
// Blocks the current thread until either there's something to dequeue |
|
|
|
// or the timeout expires. Returns false without setting `item` if the |
|
|
|
// timeout expires, otherwise assigns to `item` and returns true. |
|
|
|
// Never allocates. Thread-safe. |
|
|
|
template<typename U, typename Rep, typename Period> |
|
|
|
inline bool wait_dequeue_timed(consumer_token_t& token, U& item, std::chrono::duration<Rep, Period> const& timeout) |
|
|
|
{ |
|
|
|
return wait_dequeue_timed(token, item, std::chrono::duration_cast<std::chrono::microseconds>(timeout).count()); |
|
|
|
} |
|
|
|
|
|
|
|
// Attempts to dequeue several elements from the queue. |
|
|
|
// Returns the number of items actually dequeued, which will |
|
|
|
// always be at least one (this method blocks until the queue |
|
|
|
// is non-empty) and at most max. |
|
|
|
// Never allocates. Thread-safe. |
|
|
|
template<typename It> |
|
|
|
inline size_t wait_dequeue_bulk(It itemFirst, size_t max) |
|
|
|
{ |
|
|
|
size_t count = 0; |
|
|
|
max = (size_t)sema->waitMany((LightweightSemaphore::ssize_t)(ssize_t)max); |
|
|
|
while (count != max) { |
|
|
|
count += inner.template try_dequeue_bulk<It&>(itemFirst, max - count); |
|
|
|
} |
|
|
|
return count; |
|
|
|
} |
|
|
|
|
|
|
|
// Attempts to dequeue several elements from the queue. |
|
|
|
// Returns the number of items actually dequeued, which can |
|
|
|
// be 0 if the timeout expires while waiting for elements, |
|
|
|
// and at most max. |
|
|
|
// Using a negative timeout indicates an indefinite timeout, |
|
|
|
// and is thus functionally equivalent to calling wait_dequeue_bulk. |
|
|
|
// Never allocates. Thread-safe. |
|
|
|
template<typename It> |
|
|
|
inline size_t wait_dequeue_bulk_timed(It itemFirst, size_t max, std::int64_t timeout_usecs) |
|
|
|
{ |
|
|
|
size_t count = 0; |
|
|
|
max = (size_t)sema->waitMany((LightweightSemaphore::ssize_t)(ssize_t)max, timeout_usecs); |
|
|
|
while (count != max) { |
|
|
|
count += inner.template try_dequeue_bulk<It&>(itemFirst, max - count); |
|
|
|
} |
|
|
|
return count; |
|
|
|
} |
|
|
|
|
|
|
|
// Attempts to dequeue several elements from the queue. |
|
|
|
// Returns the number of items actually dequeued, which can |
|
|
|
// be 0 if the timeout expires while waiting for elements, |
|
|
|
// and at most max. |
|
|
|
// Never allocates. Thread-safe. |
|
|
|
template<typename It, typename Rep, typename Period> |
|
|
|
inline size_t wait_dequeue_bulk_timed(It itemFirst, size_t max, std::chrono::duration<Rep, Period> const& timeout) |
|
|
|
{ |
|
|
|
return wait_dequeue_bulk_timed<It&>(itemFirst, max, std::chrono::duration_cast<std::chrono::microseconds>(timeout).count()); |
|
|
|
} |
|
|
|
|
|
|
|
// Attempts to dequeue several elements from the queue using an explicit consumer token. |
|
|
|
// Returns the number of items actually dequeued, which will |
|
|
|
// always be at least one (this method blocks until the queue |
|
|
|
// is non-empty) and at most max. |
|
|
|
// Never allocates. Thread-safe. |
|
|
|
template<typename It> |
|
|
|
inline size_t wait_dequeue_bulk(consumer_token_t& token, It itemFirst, size_t max) |
|
|
|
{ |
|
|
|
size_t count = 0; |
|
|
|
max = (size_t)sema->waitMany((LightweightSemaphore::ssize_t)(ssize_t)max); |
|
|
|
while (count != max) { |
|
|
|
count += inner.template try_dequeue_bulk<It&>(token, itemFirst, max - count); |
|
|
|
} |
|
|
|
return count; |
|
|
|
} |
|
|
|
|
|
|
|
// Attempts to dequeue several elements from the queue using an explicit consumer token. |
|
|
|
// Returns the number of items actually dequeued, which can |
|
|
|
// be 0 if the timeout expires while waiting for elements, |
|
|
|
// and at most max. |
|
|
|
// Using a negative timeout indicates an indefinite timeout, |
|
|
|
// and is thus functionally equivalent to calling wait_dequeue_bulk. |
|
|
|
// Never allocates. Thread-safe. |
|
|
|
template<typename It> |
|
|
|
inline size_t wait_dequeue_bulk_timed(consumer_token_t& token, It itemFirst, size_t max, std::int64_t timeout_usecs) |
|
|
|
{ |
|
|
|
size_t count = 0; |
|
|
|
max = (size_t)sema->waitMany((LightweightSemaphore::ssize_t)(ssize_t)max, timeout_usecs); |
|
|
|
while (count != max) { |
|
|
|
count += inner.template try_dequeue_bulk<It&>(token, itemFirst, max - count); |
|
|
|
} |
|
|
|
return count; |
|
|
|
} |
|
|
|
|
|
|
|
// Attempts to dequeue several elements from the queue using an explicit consumer token. |
|
|
|
// Returns the number of items actually dequeued, which can |
|
|
|
// be 0 if the timeout expires while waiting for elements, |
|
|
|
// and at most max. |
|
|
|
// Never allocates. Thread-safe. |
|
|
|
template<typename It, typename Rep, typename Period> |
|
|
|
inline size_t wait_dequeue_bulk_timed(consumer_token_t& token, It itemFirst, size_t max, std::chrono::duration<Rep, Period> const& timeout) |
|
|
|
{ |
|
|
|
return wait_dequeue_bulk_timed<It&>(token, itemFirst, max, std::chrono::duration_cast<std::chrono::microseconds>(timeout).count()); |
|
|
|
} |
|
|
|
|
|
|
|
|
|
|
|
// Returns an estimate of the total number of elements currently in the queue. This |
|
|
|
// estimate is only accurate if the queue has completely stabilized before it is called |
|
|
|
// (i.e. all enqueue and dequeue operations have completed and their memory effects are |
|
|
|
// visible on the calling thread, and no further operations start while this method is |
|
|
|
// being called). |
|
|
|
// Thread-safe. |
|
|
|
inline size_t size_approx() const |
|
|
|
{ |
|
|
|
return (size_t)sema->availableApprox(); |
|
|
|
} |
|
|
|
|
|
|
|
|
|
|
|
// Returns true if the underlying atomic variables used by |
|
|
|
// the queue are lock-free (they should be on most platforms). |
|
|
|
// Thread-safe. |
|
|
|
static constexpr bool is_lock_free() |
|
|
|
{ |
|
|
|
return ConcurrentQueue::is_lock_free(); |
|
|
|
} |
|
|
|
|
|
|
|
|
|
|
|
private: |
|
|
|
template<typename U, typename A1, typename A2> |
|
|
|
static inline U* create(A1&& a1, A2&& a2) |
|
|
|
{ |
|
|
|
void* p = (Traits::malloc)(sizeof(U)); |
|
|
|
return p != nullptr ? new (p) U(std::forward<A1>(a1), std::forward<A2>(a2)) : nullptr; |
|
|
|
} |
|
|
|
|
|
|
|
template<typename U> |
|
|
|
static inline void destroy(U* p) |
|
|
|
{ |
|
|
|
if (p != nullptr) { |
|
|
|
p->~U(); |
|
|
|
} |
|
|
|
(Traits::free)(p); |
|
|
|
} |
|
|
|
|
|
|
|
private: |
|
|
|
ConcurrentQueue inner; |
|
|
|
std::unique_ptr<LightweightSemaphore, void (*)(LightweightSemaphore*)> sema; |
|
|
|
}; |
|
|
|
|
|
|
|
|
|
|
|
template<typename T, typename Traits> |
|
|
|
inline void swap(BlockingConcurrentQueue<T, Traits>& a, BlockingConcurrentQueue<T, Traits>& b) MOODYCAMEL_NOEXCEPT |
|
|
|
{ |
|
|
|
a.swap(b); |
|
|
|
} |
|
|
|
|
|
|
|
} // end namespace moodycamel |