Initial checkin of gRPC to third_party/

third_party/grpc/include/grpc++/alarm.h

+/*
+ *
+ * Copyright 2015-2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+/// An Alarm posts the user provided tag to its associated completion queue upon
+/// expiry or cancellation.
+#ifndef GRPCXX_ALARM_H
+#define GRPCXX_ALARM_H
+
+#include <grpc++/impl/codegen/completion_queue.h>
+#include <grpc++/impl/codegen/completion_queue_tag.h>
+#include <grpc++/impl/codegen/grpc_library.h>
+#include <grpc++/impl/codegen/time.h>
+#include <grpc++/impl/grpc_library.h>
+#include <grpc/grpc.h>
+
+struct grpc_alarm;
+
+namespace grpc {
+
+class CompletionQueue;
+
+/// A thin wrapper around \a grpc_alarm (see / \a / src/core/surface/alarm.h).
+class Alarm : private GrpcLibrary {
+ public:
+  /// Create a completion queue alarm instance associated to \a cq.
+  ///
+  /// Once the alarm expires (at \a deadline) or it's cancelled (see \a Cancel),
+  /// an event with tag \a tag will be added to \a cq. If the alarm expired, the
+  /// event's success bit will be true, false otherwise (ie, upon cancellation).
+  /// \internal We rely on the presence of \a cq for grpc initialization. If \a
+  /// cq were ever to be removed, a reference to a static
+  /// internal::GrpcLibraryInitializer instance would need to be introduced
+  /// here. \endinternal.
+  template <typename T>
+  Alarm(CompletionQueue* cq, const T& deadline, void* tag)
+      : tag_(tag),
+        alarm_(grpc_alarm_create(cq->cq(), TimePoint<T>(deadline).raw_time(),
+                                 static_cast<void*>(&tag_))) {}
+
+  /// Destroy the given completion queue alarm, cancelling it in the process.
+  ~Alarm() { grpc_alarm_destroy(alarm_); }
+
+  /// Cancel a completion queue alarm. Calling this function over an alarm that
+  /// has already fired has no effect.
+  void Cancel() { grpc_alarm_cancel(alarm_); }
+
+ private:
+  class AlarmEntry : public CompletionQueueTag {
+   public:
+    AlarmEntry(void* tag) : tag_(tag) {}
+    bool FinalizeResult(void** tag, bool* status) GRPC_OVERRIDE {
+      *tag = tag_;
+      return true;
+    }
+
+   private:
+    void* tag_;
+  };
+
+  AlarmEntry tag_;
+  grpc_alarm* const alarm_;  // owned
+};
+
+}  // namespace grpc
+
+#endif  // GRPCXX_ALARM_H