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, 146 insertions, 0 deletions

diff --git a/src/vpp-api/vom/object_base.hpp b/src/vpp-api/vom/object_base.hpp
new file mode 100644
index 00000000000..2edafc58466
--- /dev/null
+++ b/src/vpp-api/vom/object_base.hpp
@@ -0,0 +1,146 @@
+/*
+ * 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_OBJECT_H__
+#define __VOM_OBJECT_H__
+
+#include <memory>
+#include <string>
+
+#include "vom/types.hpp"
+
+namespace VOM {
+/**
+ * A base class for all object_base in the VPP object_base-Model.
+ *  provides the abstract interface.
+ */
+class object_base
+{
+public:
+  /**
+   * convert to string format for debug purposes
+   */
+  virtual std::string to_string() const = 0;
+
+  /**
+   * Sweep/reap the object if still stale
+   */
+  virtual void sweep(void) = 0;
+
+  /**
+   * replay the object to create it in hardware
+   */
+  virtual void replay(void) = 0;
+
+protected:
+  /**
+   * Constructable by derived classes only
+   */
+  object_base() = default;
+  /**
+   * Destructor
+   */
+  virtual ~object_base() = default;
+
+private:
+  /**
+   * note we are not maintaining dependencies back to the
+   * keys. i.e. this object does not know all the keys that
+   * refer to it.
+   */
+};
+
+/**
+ * object state
+ */
+enum obj_state_t
+{
+  OBJECT_STATE_NONE = 0,
+  /**
+   * indicates the object is stale. This flag is set
+   * when a new epoch is declared. the flag is cleared
+   * when the object is updated in the new epoch. If the
+   * flag is still set after convergence is declared then
+   * the object is deleted
+   */
+  OBJECT_STATE_STALE,
+};
+
+/**
+ * A represenation of a reference to a VPP object.
+ *  the reference counting is held through the use of shared pointers.
+ * We also maintain the state of the object ready for mark n' sweep.
+ */
+class object_ref
+{
+public:
+  /**
+   * Constructor
+   */
+  object_ref(std::shared_ptr<object_base> obj);
+
+  /**
+   * less than operator
+   */
+  bool operator<(const object_ref& other) const;
+
+  /**
+   * Return the shared pointer
+   */
+  std::shared_ptr<object_base> obj() const;
+
+  /**
+   * Mark the reference object as stale
+   */
+  void mark() const;
+
+  /**
+   * Clear the stale flag on the object
+   */
+  void clear() const;
+
+  /**
+   * Query if the object is stale
+   */
+  bool stale() const;
+
+private:
+  /**
+   * The reference object
+   */
+  std::shared_ptr<object_base> m_obj;
+
+  /**
+   * Not part of the key (in the set) so we can change it
+   * whilst iterating
+   */
+  mutable obj_state_t m_state;
+};
+
+/**
+ * ostream print of a VPP Obect
+ */
+std::ostream& operator<<(std::ostream& os, const object_base& o);
+};
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "mozilla")
+ * End:
+ */
+
+#endif