New cpp folder structure

Signed-off-by: Alexander Borsuk <me@alex.bio>

libs/base/thread_safe_queue.hpp

@@ -0,0 +1,75 @@
+#pragma once
+
+#include <condition_variable>
+#include <mutex>
+#include <queue>
+
+namespace threads
+{
+template <typename T>
+class ThreadSafeQueue
+{
+public:
+  ThreadSafeQueue() = default;
+  ThreadSafeQueue(ThreadSafeQueue const & other)
+  {
+    std::lock_guard<std::mutex> lk(other.m_mutex);
+    m_queue = other.m_queue;
+  }
+
+  void Push(T const & value)
+  {
+    {
+      std::lock_guard lk(m_mutex);
+      m_queue.push(value);
+    }
+    m_cond.notify_one();
+  }
+
+  void Push(T && value)
+  {
+    {
+      std::lock_guard lk(m_mutex);
+      m_queue.push(std::move(value));
+    }
+    m_cond.notify_one();
+  }
+
+  void WaitAndPop(T & value)
+  {
+    std::unique_lock lk(m_mutex);
+    m_cond.wait(lk, [this]{ return !m_queue.empty(); });
+    value = std::move(m_queue.front());
+    m_queue.pop();
+  }
+
+  bool TryPop(T & value)
+  {
+    std::lock_guard lk(m_mutex);
+    if (m_queue.empty())
+      return false;
+
+    value = std::move(m_queue.front());
+    m_queue.pop();
+    return true;
+
+  }
+
+  bool Empty() const
+  {
+    std::lock_guard lk(m_mutex);
+    return m_queue.empty();
+  }
+
+  size_t Size() const
+  {
+    std::lock_guard lk(m_mutex);
+    return m_queue.size();
+  }
+
+private:
+  mutable std::mutex m_mutex;
+  std::queue<T> m_queue;
+  std::condition_variable m_cond;
+};
+}  // namespace threads