From ae6fda8638d9abd2e02d8d4b57c8e5494e0847e3 Mon Sep 17 00:00:00 2001
From: Wunkolo <Wunkolo@gmail.com>
Date: Sat, 24 Jun 2023 11:43:10 +0300
Subject: [PATCH] logging: Convert backend_thread into an std::jthread

Was getting an unhandled `invalid_argument` [exception](https://en.cppreference.com/w/cpp/thread/thread/join) during
shutdown on my linux machine. This removes the need for a `StopBackendThread` function entirely since `jthread`
[automatically handles both checking if the thread is joinable and stopping the token before attempting to join](https://en.cppreference.com/w/cpp/thread/jthread/~jthread) in the case that `StartBackendThread` was never called.
---
 src/common/logging/backend.cpp | 18 ++++++------------
 1 file changed, 6 insertions(+), 12 deletions(-)

diff --git a/src/common/logging/backend.cpp b/src/common/logging/backend.cpp
index ad01c2437..d342ff466 100644
--- a/src/common/logging/backend.cpp
+++ b/src/common/logging/backend.cpp
@@ -265,7 +265,8 @@ private:
             if (sig <= 0) {
                 abort();
             }
-            StopBackendThread();
+            backend_thread.request_stop();
+            backend_thread.join();
             const auto signal_entry =
                 CreateEntry(Class::Log, Level::Critical, "?", 0, "?",
                             fmt::vformat("Received signal {}", fmt::make_format_args(sig)));
@@ -308,18 +309,17 @@ private:
             SleepForever();
         }
 #endif
-        StopBackendThread();
     }
 
     void StartBackendThread() {
-        backend_thread = std::thread([this] {
+        backend_thread = std::jthread([this](std::stop_token stop_token) {
             Common::SetCurrentThreadName("citra:Log");
             Entry entry;
             const auto write_logs = [this, &entry]() {
                 ForEachBackend([&entry](Backend& backend) { backend.Write(entry); });
             };
-            while (!stop.stop_requested()) {
-                entry = message_queue.PopWait(stop.get_token());
+            while (!stop_token.stop_requested()) {
+                entry = message_queue.PopWait(stop_token);
                 if (entry.filename != nullptr) {
                     write_logs();
                 }
@@ -333,11 +333,6 @@ private:
         });
     }
 
-    void StopBackendThread() {
-        stop.request_stop();
-        backend_thread.join();
-    }
-
     Entry CreateEntry(Class log_class, Level log_level, const char* filename, unsigned int line_nr,
                       const char* function, std::string&& message) const {
         using std::chrono::duration_cast;
@@ -402,8 +397,7 @@ private:
     ColorConsoleBackend color_console_backend{};
     FileBackend file_backend;
 
-    std::stop_source stop;
-    std::thread backend_thread;
+    std::jthread backend_thread;
     MPSCQueue<Entry, true> message_queue{};
     std::chrono::steady_clock::time_point time_origin{std::chrono::steady_clock::now()};