intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 39 insertions, 0 deletions

diff --git a/library/cpp/messagebus/session_job_count.h b/library/cpp/messagebus/session_job_count.h
new file mode 100644
index 0000000000..23aca618b1
--- /dev/null
+++ b/library/cpp/messagebus/session_job_count.h
@@ -0,0 +1,39 @@
+#pragma once
+
+#include <util/system/atomic.h>
+#include <util/system/condvar.h>
+#include <util/system/mutex.h>
+
+namespace NBus {
+    namespace NPrivate {
+        class TBusSessionJobCount {
+        private:
+            TAtomic JobCount;
+
+            TMutex Mutex;
+            TCondVar CondVar;
+
+        public:
+            TBusSessionJobCount();
+            ~TBusSessionJobCount();
+
+            void Add(unsigned delta) {
+                AtomicAdd(JobCount, delta);
+            }
+
+            void Increment() {
+                Add(1);
+            }
+
+            void Decrement() {
+                if (AtomicDecrement(JobCount) == 0) {
+                    TGuard<TMutex> guard(Mutex);
+                    CondVar.BroadCast();
+                }
+            }
+
+            void WaitForZero();
+        };
+
+    }
+}