spdlog/include/spdlog/details/async_logger_impl.h

//
// Copyright(c) 2015 Gabi Melman.
// Distributed under the MIT License (http://opensource.org/licenses/MIT)
//

#pragma once

// async logger implementation
// uses a thread pool to perform the actual logging

#include "spdlog/details/thread_pool.h"

#include <chrono>
#include <memory>
#include <string>

template<typename It>
inline spdlog::async_logger::async_logger(
    std::string logger_name, const It &begin, const It &end, std::weak_ptr<details::thread_pool> tp, async_overflow_policy overflow_policy)
    : logger(std::move(logger_name), begin, end)
    , thread_pool_(tp)
    , overflow_policy_(overflow_policy)
{
}

inline spdlog::async_logger::async_logger(
    std::string logger_name, sinks_init_list sinks_list, std::weak_ptr<details::thread_pool> tp, async_overflow_policy overflow_policy)
    : async_logger(std::move(logger_name), sinks_list.begin(), sinks_list.end(), tp, overflow_policy)
{
}

inline spdlog::async_logger::async_logger(
    std::string logger_name, sink_ptr single_sink, std::weak_ptr<details::thread_pool> tp, async_overflow_policy overflow_policy)
    : async_logger(std::move(logger_name), {single_sink}, tp, overflow_policy)
{
}

// send the log message to the thread pool
inline void spdlog::async_logger::sink_it_(details::log_msg &msg)
{
#if defined(SPDLOG_ENABLE_MESSAGE_COUNTER)
    incr_msg_counter_(msg);
#endif
    if (auto pool_ptr = thread_pool_.lock())
    {
        pool_ptr->post_log(shared_from_this(), std::move(msg), overflow_policy_);
    }
    else
    {
        throw spdlog_ex("async log: thread pool doesn't exist anymore");
    }
}

// send flush request to the thread pool
inline void spdlog::async_logger::flush_()
{
    if (auto pool_ptr = thread_pool_.lock())
    {
        pool_ptr->post_flush(shared_from_this(), overflow_policy_);
    }
    else
    {
        throw spdlog_ex("async flush: thread pool doesn't exist anymore");
    }
}

//
// backend functions - called from the thread pool to do the actual job
//
inline void spdlog::async_logger::backend_log_(details::log_msg &incoming_log_msg)
{
    try
    {
        for (auto &s : sinks_)
        {
            if (s->should_log(incoming_log_msg.level))
            {
                s->log(incoming_log_msg);
            }
        }
    }
    SPDLOG_CATCH_AND_HANDLE

    if (should_flush_(incoming_log_msg))
    {
        backend_flush_();
    }
}

inline void spdlog::async_logger::backend_flush_()
{
    try
    {
        for (auto &sink : sinks_)
        {
            sink->flush();
        }
    }
    SPDLOG_CATCH_AND_HANDLE
}


inline std::shared_ptr<spdlog::logger> spdlog::async_logger::clone(std::string new_name)
{
    auto cloned = std::make_shared<spdlog::async_logger>(std::move(new_name),
                                                         sinks_.begin(), sinks_.end(),
                                                         thread_pool_,
                                                         overflow_policy_);

    cloned->set_level(this->level());
    cloned->flush_on(this->flush_level());
    cloned->set_error_handler(this->error_handler());
    return std::move(cloned);
}