removed debug printf

include/spdlog/details/async_log_helper.h

@@ -14,11 +14,12 @@
 
 #include "../common.h"
 #include "../details/log_msg.h"
-#include "../details/mpmc_bounded_q.h"
+#include "../details/mpmc_blocking_q.h"
 #include "../details/os.h"
 #include "../formatter.h"
 #include "../sinks/sink.h"
 
+#include<iostream>
 #include <chrono>
 #include <exception>
 #include <functional>
@@ -27,12 +28,13 @@
 #include <thread>
 #include <utility>
 #include <vector>
+#include <condition_variable>
 
 namespace spdlog {
-namespace details {
+	namespace details {
 
-class async_log_helper
-{
+		class async_log_helper
+		{
 			// Async msg to move to/from the queue
 			// Movable only. should never be copied
 			enum class async_msg_type
@@ -115,9 +117,9 @@ class async_log_helper
 				}
 			};
 
-public:
+		public:
 			using item_type = async_msg;
-    using q_type = details::mpmc_bounded_queue<item_type>;
+			using q_type = details::mpmc_bounded_queue <item_type>;
 
 			using clock = std::chrono::steady_clock;
 
@@ -136,11 +138,11 @@ public:
 
 			void set_formatter(formatter_ptr msg_formatter);
 
-    void flush(bool wait_for_q);
+			void flush();
 
 			void set_error_handler(spdlog::log_err_handler err_handler);
 
-private:
+		private:
 			formatter_ptr _formatter;
 			std::vector<std::shared_ptr<sinks::sink>> _sinks;
 
@@ -149,9 +151,7 @@ private:
 
 			log_err_handler _err_handler;
 
-    bool _flush_requested;
-
-    bool _terminate_requested;
+			std::chrono::time_point<log_clock> _last_flush;
 
 			// overflow policy
 			const async_overflow_policy _overflow_policy;
@@ -165,27 +165,29 @@ private:
 			// worker thread teardown callback
 			const std::function<void()> _worker_teardown_cb;
 
+			std::mutex null_mutex_;
+			//null_mutex null_mutex_;
+			std::condition_variable_any not_empty_cv_;
+			std::condition_variable_any not_full_cv_;
+
 			// worker thread
 			std::thread _worker_thread;
 
-    void push_msg(async_msg &&new_msg);
+			void enqueue_msg(async_msg &&new_msg, async_overflow_policy policy);
 
 			// worker thread main loop
 			void worker_loop();
 
-    // pop next message from the queue and process it. will set the last_pop to the pop time
+			// dequeue next message from the queue and process it. 
 			// return false if termination of the queue is required
-    bool process_next_msg(log_clock::time_point &last_pop, log_clock::time_point &last_flush);
+			bool process_next_msg();
 
-    void handle_flush_interval(log_clock::time_point &now, log_clock::time_point &last_flush);
+			void handle_flush_interval();
 
-    // sleep,yield or return immediately using the time passed since last message as a hint
-    static void sleep_or_yield(const spdlog::log_clock::time_point &now, const log_clock::time_point &last_op_time);
+			void flush_sinks();
 			
-    // wait until the queue is empty
-    void wait_empty_q();
-};
-} // namespace details
+		};
+	} // namespace details
 } // namespace spdlog
 
 ///////////////////////////////////////////////////////////////////////////////
@@ -198,8 +200,7 @@ inline spdlog::details::async_log_helper::async_log_helper(formatter_ptr formatt
 	, _sinks(std::move(sinks))
 	, _q(queue_size)
 	, _err_handler(std::move(err_handler))
-    , _flush_requested(false)
-    , _terminate_requested(false)
+	, _last_flush(os::now())
 	, _overflow_policy(overflow_policy)
 	, _worker_warmup_cb(std::move(worker_warmup_cb))
 	, _flush_interval_ms(flush_interval_ms)
@@ -214,7 +215,7 @@ inline spdlog::details::async_log_helper::~async_log_helper()
 {
 	try
 	{
-        push_msg(async_msg(async_msg_type::terminate));
+		enqueue_msg(async_msg(async_msg_type::terminate), async_overflow_policy::block_retry);
 		_worker_thread.join();
 	}
 	catch (...) // don't crash in destructor
@@ -225,31 +226,28 @@ inline spdlog::details::async_log_helper::~async_log_helper()
 // Try to push and block until succeeded (if the policy is not to discard when the queue is full)
 inline void spdlog::details::async_log_helper::log(const details::log_msg &msg)
 {	
-    push_msg(async_msg(msg));
+	enqueue_msg(async_msg(msg), _overflow_policy);	
 }
 
-inline void spdlog::details::async_log_helper::push_msg(details::async_log_helper::async_msg &&new_msg)
+inline void spdlog::details::async_log_helper::enqueue_msg(details::async_log_helper::async_msg &&new_msg, async_overflow_policy policy)
 {
-    if (!_q.enqueue(std::move(new_msg)) && _overflow_policy != async_overflow_policy::discard_log_msg)
+
+	// block until succeeded pushing to the queue
+	if (policy == async_overflow_policy::block_retry)
 	{
-        auto last_op_time = details::os::now();
-        auto now = last_op_time;
-        do
+		_q.enqueue(std::move(new_msg));
+	}
+	else
 	{
-            now = details::os::now();
-            sleep_or_yield(now, last_op_time);
-        } while (!_q.enqueue(std::move(new_msg)));
+		_q.enqueue_nowait(std::move(new_msg));
 	}
+	
 }
 
 // optionally wait for the queue be empty and request flush from the sinks
-inline void spdlog::details::async_log_helper::flush(bool wait_for_q)
+inline void spdlog::details::async_log_helper::flush()
 {
-    push_msg(async_msg(async_msg_type::flush));
-    if (wait_for_q)
-    {
-        wait_empty_q(); // return when queue is empty
-    }
+	enqueue_msg(async_msg(async_msg_type::flush), _overflow_policy);
 }
 
 inline void spdlog::details::async_log_helper::worker_loop()
@@ -258,14 +256,12 @@ inline void spdlog::details::async_log_helper::worker_loop()
 	{
 		_worker_warmup_cb();
 	}
-    auto last_pop = details::os::now();
-    auto last_flush = last_pop;
 	auto active = true;
 	while (active)
 	{
 		try
 		{
-            active = process_next_msg(last_pop, last_flush);
+			active = process_next_msg();		
 		}
 		catch (const std::exception &ex)
 		{
@@ -284,23 +280,27 @@ inline void spdlog::details::async_log_helper::worker_loop()
 
 // process next message in the queue
 // return true if this thread should still be active (while no terminate msg was received)
-inline bool spdlog::details::async_log_helper::process_next_msg(log_clock::time_point &last_pop, log_clock::time_point &last_flush)
+inline bool spdlog::details::async_log_helper::process_next_msg()
 {
 	async_msg incoming_async_msg;
-
-    if (_q.dequeue(incoming_async_msg))
+	bool dequeued = _q.dequeue_for(incoming_async_msg, std::chrono::milliseconds(1000));		
+	if (!dequeued)
 	{	
-        last_pop = details::os::now();
+		handle_flush_interval();
+		return true;
+	}
+	
 	switch (incoming_async_msg.msg_type)
 	{
 	case async_msg_type::flush:
-            _flush_requested = true;
-            break;
+		flush_sinks();
+		return true;
+		
 
 	case async_msg_type::terminate:
-            _flush_requested = true;
-            _terminate_requested = true;
-            break;
+		//flush_sinks();
+		return false;
+		
 
 	default:
 		log_msg incoming_log_msg;
@@ -313,81 +313,47 @@ inline bool spdlog::details::async_log_helper::process_next_msg(log_clock::time_
 				s->log(incoming_log_msg);
 			}
 		}
-        }
 		return true;		
 	}
+	assert(false);
+	return true; // should not be reached
 
-    // Handle empty queue..
-    // This is the only place where the queue can terminate or flush to avoid losing messages already in the queue
-    auto now = details::os::now();
-    handle_flush_interval(now, last_flush);
-    sleep_or_yield(now, last_pop);
-    return !_terminate_requested;
 }
 
-// flush all sinks if _flush_interval_ms has expired
-inline void spdlog::details::async_log_helper::handle_flush_interval(log_clock::time_point &now, log_clock::time_point &last_flush)
+// flush all sinks if _flush_interval_ms has expired. only called if queue is empty
+inline void spdlog::details::async_log_helper::handle_flush_interval()
 {		
-    auto should_flush =
-        _flush_requested || (_flush_interval_ms != std::chrono::milliseconds::zero() && now - last_flush >= _flush_interval_ms);
-    if (should_flush)
+	if (_flush_interval_ms == std::chrono::milliseconds::zero())
 	{
-        for (auto &s : _sinks)
-        {
-            s->flush();
+		return;
 	}
-        now = last_flush = details::os::now();
-        _flush_requested = false;
+	auto delta = details::os::now() - _last_flush;;		
+	if (delta >= _flush_interval_ms)
+	{					
+		flush_sinks();
 	}
 }
 
+
 inline void spdlog::details::async_log_helper::set_formatter(formatter_ptr msg_formatter)
 {
 	_formatter = std::move(msg_formatter);
 }
 
-// spin, yield or sleep. use the time passed since last message as a hint
-inline void spdlog::details::async_log_helper::sleep_or_yield(
-    const spdlog::log_clock::time_point &now, const spdlog::log_clock::time_point &last_op_time)
-{
-    using std::chrono::microseconds;
-    using std::chrono::milliseconds;
-
-    auto time_since_op = now - last_op_time;
-
-    // spin upto 50 micros
-    if (time_since_op <= microseconds(50))
-    {
-        return;
-    }
-
-    // yield upto 150 micros
-    if (time_since_op <= microseconds(100))
-    {
-        return std::this_thread::yield();
-    }
 
-    // sleep for 20 ms upto 200 ms
-    if (time_since_op <= milliseconds(200))
-    {
-        return details::os::sleep_for_millis(20);
-    }
-
-    // sleep for 500 ms
-    return details::os::sleep_for_millis(500);
+inline void spdlog::details::async_log_helper::set_error_handler(spdlog::log_err_handler err_handler)
+{
+	_err_handler = std::move(err_handler);
 }
 
-// wait for the queue to be empty
-inline void spdlog::details::async_log_helper::wait_empty_q()
+
+// flush all sinks if _flush_interval_ms has expired. only called if queue is empty
+inline void spdlog::details::async_log_helper::flush_sinks()
 {	
-    auto last_op = details::os::now();
-    while (!_q.is_empty())
+	for (auto &s : _sinks)
 	{
-        sleep_or_yield(details::os::now(), last_op);
+		s->flush();
 	}
+	_last_flush = os::now();
 }
 
-inline void spdlog::details::async_log_helper::set_error_handler(spdlog::log_err_handler err_handler)
-{
-    _err_handler = std::move(err_handler);
-}