intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 86 insertions, 0 deletions

diff --git a/library/cpp/messagebus/futex_like.h b/library/cpp/messagebus/futex_like.h
new file mode 100644
index 00000000000..31d60c60f10
--- /dev/null
+++ b/library/cpp/messagebus/futex_like.h
@@ -0,0 +1,86 @@
+#pragma once
+
+#include <util/system/condvar.h>
+#include <util/system/mutex.h>
+#include <util/system/platform.h>
+
+class TFutexLike {
+private:
+#ifdef _linux_
+    int Value;
+#else
+    TAtomic Value;
+    TMutex Mutex;
+    TCondVar CondVar;
+#endif
+
+public:
+    TFutexLike()
+        : Value(0)
+    {
+    }
+
+    int AddAndGet(int add) {
+#ifdef _linux_
+        //return __atomic_add_fetch(&Value, add, __ATOMIC_SEQ_CST);
+        return __sync_add_and_fetch(&Value, add);
+#else
+        return AtomicAdd(Value, add);
+#endif
+    }
+
+    int GetAndAdd(int add) {
+        return AddAndGet(add) - add;
+    }
+
+// until we have modern GCC
+#if 0
+    int GetAndSet(int newValue) {
+#ifdef _linux_
+        return __atomic_exchange_n(&Value, newValue, __ATOMIC_SEQ_CST);
+#else
+        return AtomicSwap(&Value, newValue);
+#endif
+    }
+#endif
+
+    int Get() {
+#ifdef _linux_
+        //return __atomic_load_n(&Value, __ATOMIC_SEQ_CST);
+        __sync_synchronize();
+        return Value;
+#else
+        return AtomicGet(Value);
+#endif
+    }
+
+    void Set(int newValue) {
+#ifdef _linux_
+        //__atomic_store_n(&Value, newValue, __ATOMIC_SEQ_CST);
+        Value = newValue;
+        __sync_synchronize();
+#else
+        AtomicSet(Value, newValue);
+#endif
+    }
+
+    int GetAndIncrement() {
+        return AddAndGet(1) - 1;
+    }
+
+    int IncrementAndGet() {
+        return AddAndGet(1);
+    }
+
+    int GetAndDecrement() {
+        return AddAndGet(-1) + 1;
+    }
+
+    int DecrementAndGet() {
+        return AddAndGet(-1);
+    }
+
+    void Wake(size_t count = Max<size_t>());
+
+    void Wait(int expected);
+};