From eb46ba2646586047bcf99dcdf9952f7a19e2b572 Mon Sep 17 00:00:00 2001
From: nanavuletic <ana.vuletic@wolkabout.com>
Date: Thu, 24 Feb 2022 17:27:55 +0100
Subject: [PATCH] Even better waits

---
 core/utilities/Buffer.h          | 11 ++++++-----
 core/utilities/CommandBuffer.cpp | 15 +++++++--------
 core/utilities/CommandBuffer.h   |  2 +-
 3 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/core/utilities/Buffer.h b/core/utilities/Buffer.h
index a3c22a51..38656223 100644
--- a/core/utilities/Buffer.h
+++ b/core/utilities/Buffer.h
@@ -62,7 +62,10 @@ template <class T> Buffer<T>::~Buffer()
 
 template <class T> void Buffer<T>::stop()
 {
-    m_exitCondition = true;
+    {
+        std::lock_guard<std::mutex> lg{m_pushLock};
+        m_exitCondition = true;
+    }
     m_condition.notify_one();
 }
 
@@ -92,7 +95,7 @@ template <class T> T Buffer<T>::pop()
 
     if (m_popQueue.empty())
     {
-        LOG(ERROR) << "Poping from empty buffer";
+        LOG(ERROR) << "Popping from empty buffer";
         return {};
     }
 
@@ -106,10 +109,8 @@ template <class T> void Buffer<T>::swapBuffers()
 {
     std::unique_lock<std::mutex> pushGuard(m_pushLock);
 
-    if (m_pushQueue.empty() && !m_exitCondition)
-    {
+    if (m_pushQueue.empty())
         m_condition.wait(pushGuard, [&] { return !m_pushQueue.empty() || m_exitCondition; });
-    }
 
     std::lock_guard<std::mutex> popGuard{m_popLock};
     std::swap(m_pushQueue, m_popQueue);
diff --git a/core/utilities/CommandBuffer.cpp b/core/utilities/CommandBuffer.cpp
index 1f83b045..9808bb36 100644
--- a/core/utilities/CommandBuffer.cpp
+++ b/core/utilities/CommandBuffer.cpp
@@ -16,8 +16,6 @@
 
 #include "CommandBuffer.h"
 
-#include <atomic>
-#include <condition_variable>
 #include <functional>
 #include <memory>
 #include <mutex>
@@ -36,7 +34,7 @@ CommandBuffer::~CommandBuffer()
     stop();
 }
 
-void CommandBuffer::pushCommand(std::shared_ptr<Command> command)
+void CommandBuffer::pushCommand(const std::shared_ptr<Command>& command)
 {
     std::unique_lock<std::mutex> unique_lock(m_lock);
 
@@ -47,7 +45,10 @@ void CommandBuffer::pushCommand(std::shared_ptr<Command> command)
 
 void CommandBuffer::stop()
 {
-    m_isRunning = false;
+    {
+        std::lock_guard<std::mutex> lg{m_lock};
+        m_isRunning = false;
+    }
     notify();
 
     if (m_worker && m_worker->joinable())
@@ -79,10 +80,8 @@ void CommandBuffer::switchBuffers()
 {
     std::unique_lock<std::mutex> unique_lock(m_lock);
 
-    if (m_pushCommandQueue.empty() && m_isRunning)
-    {
-        m_condition.wait(unique_lock);
-    }
+    if (m_pushCommandQueue.empty())
+        m_condition.wait(unique_lock, [&] { return !m_pushCommandQueue.empty() || !m_isRunning; });
 
     std::swap(m_pushCommandQueue, m_popCommandQueue);
 }
diff --git a/core/utilities/CommandBuffer.h b/core/utilities/CommandBuffer.h
index bc7ba7aa..a2f8ef52 100644
--- a/core/utilities/CommandBuffer.h
+++ b/core/utilities/CommandBuffer.h
@@ -35,7 +35,7 @@ class CommandBuffer
     CommandBuffer();
     virtual ~CommandBuffer();
 
-    void pushCommand(std::shared_ptr<Command> command);
+    void pushCommand(const std::shared_ptr<Command>& command);
 
     void stop();