VPP Object Model (VOM)

The VOM is a C++ library for use by clients/agents of VPP for programming
state. It uses the binary APIs to do so. Various other common client side
functions are also provided. Please see om.hpp for a more detailed description.

Change-Id: Ib756bfe99817093815a9e26ccf464aa5583fc523
Signed-off-by: Neale Ranns <neale.ranns@cisco.com>
Co-authored-by: Mohsin Kazmi <sykazmi@cisco.com>

1 files changed, 117 insertions, 0 deletions

diff --git a/src/vpp-api/vom/event_cmd.hpp b/src/vpp-api/vom/event_cmd.hpp
new file mode 100644
index 00000000000..a0e9b4af112
--- /dev/null
+++ b/src/vpp-api/vom/event_cmd.hpp
@@ -0,0 +1,117 @@
+/*
+ * Copyright (c) 2017 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef __VOM_EVENT_CMD_H__
+#define __VOM_EVENT_CMD_H__
+
+#include <mutex>
+
+#include "vom/rpc_cmd.hpp"
+
+#include <vapi/vapi.hpp>
+
+namespace VOM {
+/**
+ * An Event command base class.
+ * Events are one of the sub-set of command type to VPP.
+ * A client performs a one time 'registration/subsription' to VPP for the
+ * event in question and then is notified asynchronously when those events
+ * occur.
+ * The model here then is that the lifetime of the event command represensts
+ * the during of the clients subscription. When the command is 'issued' the
+ * subscription begins, when it is 'retired' the subscription ends. For the
+ * subscription duration the client will be notified as events are recieved.
+ * The client can then 'pop' these events from this command object.
+ */
+template <typename WANT, typename EVENT>
+class event_cmd : public rpc_cmd<HW::item<bool>, rc_t, WANT>
+{
+public:
+  /**
+   * Default constructor
+   */
+  event_cmd(HW::item<bool>& b)
+    : rpc_cmd<HW::item<bool>, rc_t, WANT>(b)
+  {
+  }
+
+  /**
+   * Default destructor
+   */
+  virtual ~event_cmd() {}
+
+  /**
+   * Typedef for the event type
+   */
+  typedef typename vapi::Event_registration<EVENT>::resp_type event_t;
+  typedef typename vapi::Event_registration<EVENT> reg_t;
+
+  typedef typename vapi::Result_set<typename reg_t::resp_type>::const_iterator
+    const_iterator;
+
+  const_iterator begin() { return (m_reg->get_result_set().begin()); }
+
+  const_iterator end() { return (m_reg->get_result_set().end()); }
+
+  void lock() { m_mutex.lock(); }
+  void unlock() { m_mutex.unlock(); }
+
+  /**
+   * flush/free all the events thus far reeived.
+   * Call with the lock held!
+   */
+  void flush() { m_reg->get_result_set().free_all_responses(); }
+
+  /**
+   * Retire the command. This is only appropriate for Event Commands
+   * As they persist until retired.
+   */
+  virtual void retire(connection& con) = 0;
+
+  vapi_error_e operator()(reg_t& dl)
+  {
+    notify();
+
+    return (VAPI_OK);
+  }
+
+protected:
+  /**
+   * Notify the command that data from VPP has arrived and been stored.
+   * The command should now inform its clients/listeners.
+   */
+  virtual void notify() = 0;
+
+  /**
+   * The VAPI event registration
+   */
+  std::unique_ptr<vapi::Event_registration<EVENT>> m_reg;
+
+  /**
+   * Mutex protection for the events
+   */
+  std::mutex m_mutex;
+};
+};
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "mozilla")
+ * End:
+ */
+
+#endif