libcryfs/vendor/spdlog/spdlog/details/thread_pool.h

121 lines
3.2 KiB
C++

// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
// Distributed under the MIT License (http://opensource.org/licenses/MIT)
#pragma once
#include "spdlog/details/log_msg_buffer.h"
#include "spdlog/details/mpmc_blocking_q.h"
#include "spdlog/details/os.h"
#include <chrono>
#include <memory>
#include <thread>
#include <vector>
#include <functional>
namespace spdlog {
class async_logger;
namespace details {
using async_logger_ptr = std::shared_ptr<spdlog::async_logger>;
enum class async_msg_type
{
log,
flush,
terminate
};
#include "spdlog/details/log_msg_buffer.h"
// Async msg to move to/from the queue
// Movable only. should never be copied
struct async_msg : log_msg_buffer
{
async_msg_type msg_type{async_msg_type::log};
async_logger_ptr worker_ptr;
async_msg() = default;
~async_msg() = default;
// should only be moved in or out of the queue..
async_msg(const async_msg &) = delete;
// support for vs2013 move
#if defined(_MSC_VER) && _MSC_VER <= 1800
async_msg(async_msg &&other)
: log_msg_buffer(std::move(other))
, msg_type(other.msg_type)
, worker_ptr(std::move(other.worker_ptr))
{}
async_msg &operator=(async_msg &&other)
{
*static_cast<log_msg_buffer *>(this) = std::move(other);
msg_type = other.msg_type;
worker_ptr = std::move(other.worker_ptr);
return *this;
}
#else // (_MSC_VER) && _MSC_VER <= 1800
async_msg(async_msg &&) = default;
async_msg &operator=(async_msg &&) = default;
#endif
// construct from log_msg with given type
async_msg(async_logger_ptr &&worker, async_msg_type the_type, const details::log_msg &m)
: log_msg_buffer{m}
, msg_type{the_type}
, worker_ptr{std::move(worker)}
{}
async_msg(async_logger_ptr &&worker, async_msg_type the_type)
: log_msg_buffer{}
, msg_type{the_type}
, worker_ptr{std::move(worker)}
{}
explicit async_msg(async_msg_type the_type)
: async_msg{nullptr, the_type}
{}
};
class thread_pool
{
public:
using item_type = async_msg;
using q_type = details::mpmc_blocking_queue<item_type>;
thread_pool(size_t q_max_items, size_t threads_n, std::function<void()> on_thread_start);
thread_pool(size_t q_max_items, size_t threads_n);
// message all threads to terminate gracefully join them
~thread_pool();
thread_pool(const thread_pool &) = delete;
thread_pool &operator=(thread_pool &&) = delete;
void post_log(async_logger_ptr &&worker_ptr, const details::log_msg &msg, async_overflow_policy overflow_policy);
void post_flush(async_logger_ptr &&worker_ptr, async_overflow_policy overflow_policy);
size_t overrun_counter();
private:
q_type q_;
std::vector<std::thread> threads_;
void post_async_msg_(async_msg &&new_msg, async_overflow_policy overflow_policy);
void worker_loop_();
// process next message in the queue
// return true if this thread should still be active (while no terminate msg
// was received)
bool process_next_msg_();
};
} // namespace details
} // namespace spdlog
#ifdef SPDLOG_HEADER_ONLY
#include "thread_pool-inl.h"
#endif