1 files changed, 46 insertions, 0 deletions
diff --git a/thirdparty/etcpak/Semaphore.hpp b/thirdparty/etcpak/Semaphore.hpp
new file mode 100644
index 0000000000..9e42dbb9e0
--- /dev/null
+++ b/thirdparty/etcpak/Semaphore.hpp
@@ -0,0 +1,46 @@
+#ifndef __DARKRL__SEMAPHORE_HPP__
+#define __DARKRL__SEMAPHORE_HPP__
+
+#include <condition_variable>
+#include <mutex>
+
+class Semaphore
+{
+public:
+    Semaphore( int count ) : m_count( count ) {}
+
+    void lock()
+    {
+        std::unique_lock<std::mutex> lock( m_mutex );
+        m_cv.wait( lock, [this](){ return m_count != 0; } );
+        m_count--;
+    }
+
+    void unlock()
+    {
+        std::lock_guard<std::mutex> lock( m_mutex );
+        m_count++;
+        m_cv.notify_one();
+    }
+
+    bool try_lock()
+    {
+        std::lock_guard<std::mutex> lock( m_mutex );
+        if( m_count == 0 )
+        {
+            return false;
+        }
+        else
+        {
+            m_count--;
+            return true;
+        }
+    }
+
+private:
+    std::mutex m_mutex;
+    std::condition_variable m_cv;
+    unsigned int m_count;
+};
+
+#endif