From 041b977523e203c26c139ae4bdfa31a113072cd0 Mon Sep 17 00:00:00 2001
From: Stenzek <stenzek@gmail.com>
Date: Thu, 31 May 2018 04:22:20 -0700
Subject: [PATCH] Common: Use GCD semaphores on macOS

Unnamed semaphores are not supported.
---
 Source/Core/Common/Semaphore.h | 26 +++++++++++++++++++++++++-
 1 file changed, 25 insertions(+), 1 deletion(-)

diff --git a/Source/Core/Common/Semaphore.h b/Source/Core/Common/Semaphore.h
index 0c48d2fb4d..d132288f2a 100644
--- a/Source/Core/Common/Semaphore.h
+++ b/Source/Core/Common/Semaphore.h
@@ -30,7 +30,31 @@ private:
 };
 }  // namespace Common
 
-#else  // _WIN32
+#elif defined(__APPLE__)
+
+#include <dispatch/dispatch.h>
+
+namespace Common
+{
+class Semaphore
+{
+public:
+  Semaphore(int initial_count, int maximum_count)
+  {
+    m_handle = dispatch_semaphore_create(0);
+    for (int i = 0; i < initial_count; i++)
+      dispatch_semaphore_signal(m_handle);
+  }
+  ~Semaphore() { dispatch_release(m_handle); }
+  void Wait() { dispatch_semaphore_wait(m_handle, DISPATCH_TIME_FOREVER); }
+  void Post() { dispatch_semaphore_signal(m_handle); }
+
+private:
+  dispatch_semaphore_t m_handle;
+};
+}  // namespace Common
+
+#else
 
 #include <semaphore.h>