From 58a30fe347e2778514b48b0f2de3c4f2bcfec82d Mon Sep 17 00:00:00 2001
From: lisyarus <lisyarus@gmail.com>
Date: Wed, 30 Sep 2020 16:16:08 +0300
Subject: [PATCH] Fix thread registration

---
 libs/log/source/log.cpp | 31 ++++++++++++++++++++++---------
 1 file changed, 22 insertions(+), 9 deletions(-)

diff --git a/libs/log/source/log.cpp b/libs/log/source/log.cpp
index a3f7cc14..bae04605 100644
--- a/libs/log/source/log.cpp
+++ b/libs/log/source/log.cpp
@@ -19,6 +19,7 @@ namespace psemek::log
 		max_thread_name_length = length;
 	}
 
+	static std::mutex thread_names_mutex;
 	static std::unordered_map<std::thread::id, std::string> thread_names;
 
 	void register_thread(std::string name)
@@ -28,14 +29,18 @@ namespace psemek::log
 
 	void register_thread(std::thread::id id, std::string name)
 	{
-		auto it = thread_names.find(id);
-		if (it != thread_names.end())
-			throw std::runtime_error("Thread \"" + name + "\" already registered!");
+		{
+			std::lock_guard lock{thread_names_mutex};
 
-		if (name.size() > max_thread_name_length)
-			throw std::runtime_error("Thread \"" + name + "\" name is too long");
+			auto it = thread_names.find(id);
+			if (it != thread_names.end())
+				throw std::runtime_error("Thread \"" + name + "\" already registered!");
 
-		thread_names[id] = name;
+			if (name.size() > max_thread_name_length)
+				throw std::runtime_error("Thread \"" + name + "\" name is too long");
+
+			thread_names[id] = name;
+		}
 
 		put_message(level::info, "Thread \"" + name + "\" registered");
 	}
@@ -59,14 +64,22 @@ namespace psemek::log
 		auto const millis = std::chrono::duration_cast<std::chrono::milliseconds>(clock::now().time_since_epoch()).count() % 1000;
 
 		auto const id = std::this_thread::get_id();
-		auto const it = thread_names.find(id);
 
-		auto const & thread_name = (it == thread_names.end()) ? unknown_thread_name : it->second;
+
+		std::string const * thread_name;
+		{
+			std::lock_guard lock{thread_names_mutex};
+			auto const it = thread_names.find(id);
+			if (it == thread_names.end())
+				thread_name = &unknown_thread_name;
+			else
+				thread_name = &(it->second);
+		}
 
 		std::ostringstream os;
 		os
 			<< '[' << std::put_time(&tm, "%Y %b %d  %H:%M:%S.") << std::setw(3) << std::setfill('0') << millis << ']'
-			<< '[' << std::setw(max_thread_name_length) << std::setfill(' ') << thread_name << ']'
+			<< '[' << std::setw(max_thread_name_length) << std::setfill(' ') << *thread_name << ']'
 			<< '[' << std::setw(7) << l << ']'
 			<< ' ' << message;