From 0c27d95e760d2a30b287f913a4d238c7af63c724 Mon Sep 17 00:00:00 2001
From: Oleg Kosenkov <oleg@kosenkov.ca>
Date: Sun, 30 Oct 2022 02:34:38 -0400
Subject: [PATCH] Userland: Use Threading::MutexLocker to lock/unlock mutexes

---
 .../PixelPaint/ImageProcessor.cpp             |  4 +---
 .../Libraries/LibAudio/ConnectionToServer.cpp |  7 ++----
 Userland/Services/AudioServer/Mixer.cpp       | 24 +++++++++----------
 3 files changed, 15 insertions(+), 20 deletions(-)

diff --git a/Userland/Applications/PixelPaint/ImageProcessor.cpp b/Userland/Applications/PixelPaint/ImageProcessor.cpp
index ab16a604ddd..7e5c31eef84 100644
--- a/Userland/Applications/PixelPaint/ImageProcessor.cpp
+++ b/Userland/Applications/PixelPaint/ImageProcessor.cpp
@@ -59,10 +59,8 @@ ErrorOr<void> ImageProcessor::enqueue_command(NonnullRefPtr<ImageProcessingComma
         m_processor_thread->detach();
     }
 
-    m_wakeup_mutex.lock();
+    Threading::MutexLocker const locker(m_wakeup_mutex);
     m_wakeup_variable.signal();
-    m_wakeup_mutex.unlock();
-
     return {};
 }
 
diff --git a/Userland/Libraries/LibAudio/ConnectionToServer.cpp b/Userland/Libraries/LibAudio/ConnectionToServer.cpp
index 7f063f8502d..5d61fa19e0b 100644
--- a/Userland/Libraries/LibAudio/ConnectionToServer.cpp
+++ b/Userland/Libraries/LibAudio/ConnectionToServer.cpp
@@ -27,9 +27,8 @@ ConnectionToServer::ConnectionToServer(NonnullOwnPtr<Core::Stream::LocalSocket>
         Core::EventLoop enqueuer_loop;
         m_enqueuer_loop = &enqueuer_loop;
         enqueuer_loop.exec();
-        m_enqueuer_loop_destruction.lock();
+        Threading::MutexLocker const locker(m_enqueuer_loop_destruction);
         m_enqueuer_loop = nullptr;
-        m_enqueuer_loop_destruction.unlock();
         return (intptr_t) nullptr;
     }))
 {
@@ -45,12 +44,10 @@ ConnectionToServer::~ConnectionToServer()
 void ConnectionToServer::die()
 {
     // We're sometimes getting here after the other thread has already exited and its event loop does no longer exist.
-    m_enqueuer_loop_destruction.lock();
-    if (m_enqueuer_loop != nullptr) {
+    if (Threading::MutexLocker const locker(m_enqueuer_loop_destruction); m_enqueuer_loop != nullptr) {
         m_enqueuer_loop->wake();
         m_enqueuer_loop->quit(0);
     }
-    m_enqueuer_loop_destruction.unlock();
     (void)m_background_audio_enqueuer->join();
 }
 
diff --git a/Userland/Services/AudioServer/Mixer.cpp b/Userland/Services/AudioServer/Mixer.cpp
index 9e8cf14d8b1..4b5cdc41bee 100644
--- a/Userland/Services/AudioServer/Mixer.cpp
+++ b/Userland/Services/AudioServer/Mixer.cpp
@@ -45,11 +45,10 @@ Mixer::Mixer(NonnullRefPtr<Core::ConfigFile> config)
 NonnullRefPtr<ClientAudioStream> Mixer::create_queue(ConnectionFromClient& client)
 {
     auto queue = adopt_ref(*new ClientAudioStream(client));
-    m_pending_mutex.lock();
-
-    m_pending_mixing.append(*queue);
-
-    m_pending_mutex.unlock();
+    {
+        Threading::MutexLocker const locker(m_pending_mutex);
+        m_pending_mixing.append(*queue);
+    }
     // Signal the mixer thread to start back up, in case nobody was connected before.
     m_mixing_necessary.signal();
 
@@ -61,14 +60,15 @@ void Mixer::mix()
     decltype(m_pending_mixing) active_mix_queues;
 
     for (;;) {
-        m_pending_mutex.lock();
-        // While we have nothing to mix, wait on the condition.
-        m_mixing_necessary.wait_while([this, &active_mix_queues]() { return m_pending_mixing.is_empty() && active_mix_queues.is_empty(); });
-        if (!m_pending_mixing.is_empty()) {
-            active_mix_queues.extend(move(m_pending_mixing));
-            m_pending_mixing.clear();
+        {
+            Threading::MutexLocker const locker(m_pending_mutex);
+            // While we have nothing to mix, wait on the condition.
+            m_mixing_necessary.wait_while([this, &active_mix_queues]() { return m_pending_mixing.is_empty() && active_mix_queues.is_empty(); });
+            if (!m_pending_mixing.is_empty()) {
+                active_mix_queues.extend(move(m_pending_mixing));
+                m_pending_mixing.clear();
+            }
         }
-        m_pending_mutex.unlock();
 
         active_mix_queues.remove_all_matching([&](auto& entry) { return !entry->client(); });