point-to-point: Update example and documentation to new API
This commit is contained in:
Tom Henderson
@@ -263,25 +263,57 @@ Defining Attributes
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We provide a way for users to access values deep in the system, without having
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to plumb accessors (pointers) through the system and walk pointer chains to get
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to them. Consider a class :cpp:class:`DropTailQueue` that has a member variable
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that is an unsigned integer :cpp:member:`m_maxPackets`; this member variable controls
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the depth of the queue.
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to them. Consider a class :cpp:class:`QueueBase` that has a member variable
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:cpp:member:`m_maxSize` controlling the depth of the queue.
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If we look at the declaration of :cpp:class:`DropTailQueue`, we see
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If we look at the declaration of :cpp:class:`QueueBase`, we see
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the following::
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class DropTailQueue : public Queue {
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class QueueBase : public Object {
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public:
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static TypeId GetTypeId (void);
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...
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private:
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std::queue<Ptr<Packet> > m_packets;
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uint32_t m_maxPackets;
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...
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QueueSize m_maxSize; //!< max queue size
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...
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};
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:cpp:class:`QueueSize` is a special type in |ns3| that allows size
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to be represented in different units::
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enum QueueSizeUnit
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{
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PACKETS, /**< Use number of packets for queue size */
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BYTES, /**< Use number of bytes for queue size */
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};
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class QueueSize
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{
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...
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private:
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...
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QueueSizeUnit m_unit; //!< unit
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uint32_t m_value; //!< queue size [bytes or packets]
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};
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Finally, the class :cpp:class:`DropTailQueue` inherits from this base
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class and provides the semantics that packets that are submitted to
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a full queue will be dropped from the back of the queue ("drop tail").
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::
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/**
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* \ingroup queue
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*
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* \brief A FIFO packet queue that drops tail-end packets on overflow
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*/
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template <typename Item>
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class DropTailQueue : public Queue<Item>
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Let's consider things that a user may want to do with the value of
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:cpp:member:`m_maxPackets`:
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:cpp:member:`m_maxSize`:
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* Set a default value for the system, such that whenever a new
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:cpp:class:`DropTailQueue` is created, this member is initialized
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@@ -294,43 +326,45 @@ functions, and some type of global default value.
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In the |ns3| attribute system, these value definitions and accessor function
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registrations are moved into the :cpp:class:`TypeId` class; *e.g*.::
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NS_OBJECT_ENSURE_REGISTERED (DropTailQueue);
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NS_OBJECT_ENSURE_REGISTERED (QueueBase);
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TypeId
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DropTailQueue::GetTypeId (void)
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QueueBase::GetTypeId (void)
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{
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static TypeId tid = TypeId ("ns3::DropTailQueue")
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.SetParent<Queue> ()
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.SetGroupName ("Network")
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.AddConstructor<DropTailQueue> ()
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.AddAttribute ("MaxPackets",
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"The maximum number of packets accepted by this DropTailQueue.",
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UintegerValue (100),
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MakeUintegerAccessor (&DropTailQueue::m_maxPackets),
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MakeUintegerChecker<uint32_t> ())
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...
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.AddAttribute ("MaxSize",
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"The max queue size",
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QueueSizeValue (QueueSize ("100p")),
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MakeQueueSizeAccessor (&QueueBase::SetMaxSize,
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&QueueBase::GetMaxSize),
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MakeQueueSizeChecker ())
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...
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;
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return tid;
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}
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The :cpp:func:`AddAttribute ()` method is performing a number of things for the
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:cpp:member:`m_maxPackets` value:
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:cpp:member:`m_maxSize` value:
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* Binding the (usually private) member variable :cpp:member:`m_maxPackets`
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to a public string ``"MaxPackets"``.
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* Providing a default value (100 packets).
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* Binding the (usually private) member variable :cpp:member:`m_maxSize`
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to a public string ``"MaxSize"``.
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* Providing a default value (0 packets).
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* Providing some help text defining the meaning of the value.
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* Providing a "Checker" (not used in this example) that can be used to set
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bounds on the allowable range of values.
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The key point is that now the value of this variable and its default value are
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accessible in the attribute namespace, which is based on strings such as
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``"MaxPackets"`` and :cpp:class:`TypeId` name strings. In the next section,
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``"MaxSize"`` and :cpp:class:`TypeId` name strings. In the next section,
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we will provide an example script that shows how users may manipulate
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these values.
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Note that initialization of the attribute relies on the macro
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``NS_OBJECT_ENSURE_REGISTERED (DropTailQueue)`` being called; if you leave this
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``NS_OBJECT_ENSURE_REGISTERED (QueueBase)`` being called; if you leave this
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out of your new class implementation, your attributes will not be initialized
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correctly.
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@@ -359,50 +393,63 @@ script for illustration, with some details stripped out. The ``main``
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function begins::
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// This is a basic example of how to use the attribute system to
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// set and get a value in the underlying system; namely, an unsigned
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// integer of the maximum number of packets in a queue
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// set and get a value in the underlying system; namely, the maximum
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// size of the FIFO queue in the PointToPointNetDevice
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//
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int
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main (int argc, char *argv[])
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{
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// By default, the MaxPackets attribute has a value of 100 packets
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// (this default can be observed in the function DropTailQueue::GetTypeId)
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//
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// Queues in ns-3 are objects that hold items (other objects) in
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// a queue structure. The C++ implementation uses templates to
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// allow queues to hold various types of items, but the most
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// common is a pointer to a packet (Ptr<Packet>).
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//
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// The maximum queue size can either be enforced in bytes ('b') or
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// packets ('p'). A special type called the ns3::QueueSize can
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// hold queue size values in either unit (bytes or packets). The
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// queue base class ns3::QueueBase has a MaxSize attribute that can
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// be set to a QueueSize.
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// By default, the MaxSize attribute has a value of 100 packets ('100p')
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// (this default can be observed in the function QueueBase::GetTypeId)
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//
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// Here, we set it to 80 packets. We could use one of two value types:
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// a string-based value or a Uinteger value
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Config::SetDefault ("ns3::DropTailQueue::MaxPackets", StringValue ("80"));
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// a string-based value or a QueueSizeValue value
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Config::SetDefault ("ns3::QueueBase::MaxSize", StringValue ("80p"));
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// The below function call is redundant
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Config::SetDefault ("ns3::DropTailQueue::MaxPackets", UintegerValue (80));
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// Allow the user to override any of the defaults and the above
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// SetDefaults () at run-time, via command-line arguments
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// For example, via "--ns3::DropTailQueue::MaxPackets=80"
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CommandLine cmd;
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// This provides yet another way to set the value from the command line:
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cmd.AddValue ("maxPackets", "ns3::DropTailQueue::MaxPackets");
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cmd.Parse (argc, argv);
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Config::SetDefault ("ns3::QueueBase::MaxSize", QueueSizeValue (QueueSize (QueueSizeUnit::PACKETS, 80)));
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The main thing to notice in the above are the two equivalent calls to
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:cpp:func:`Config::SetDefault ()`. This is how we set the default value
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for all subsequently instantiated :cpp:class:`DropTailQueue`\s. We illustrate
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that two types of ``Value`` classes, a :cpp:class:`StringValue` and
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a :cpp:class:`UintegerValue` class, can be used to assign the value
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to the attribute named by "ns3::DropTailQueue::MaxPackets".
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a :cpp:class:`QueueSizeValue` class, can be used to assign the value
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to the attribute named by "ns3::QueueBase::MaxSize".
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It's also possible to manipulate Attributes using the :cpp:class:`CommandLine`;
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we saw some examples early in the Tutorial. In particular, it is
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straightforward to add a shorthand argument name, such as ``--maxPackets``,
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It is also possible to manipulate Attributes using the :cpp:class:`CommandLine`;
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we saw some examples early in the |ns3| Tutorial. In particular, it is
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straightforward to add a shorthand argument name, such as ``--maxSize``,
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for an Attribute that is particular relevant for your model, in this case
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``"ns3::DropTailQueue::MaxPackets"``. This has the additional feature that
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``"ns3::QueueBase::MaxSize"``. This has the additional feature that
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the help string for the Attribute will be printed as part of the usage
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message for the script. For more information see
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the :cpp:class:`CommandLine` API documentation.
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::
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// Allow the user to override any of the defaults and the above
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// SetDefaults() at run-time, via command-line arguments
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// For example, via "--ns3::QueueBase::MaxSize=80p"
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CommandLine cmd;
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// This provides yet another way to set the value from the command line:
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cmd.AddValue ("maxSize", "ns3::QueueBase::MaxSize");
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cmd.Parse (argc, argv);
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Now, we will create a few objects using the low-level API. Our
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newly created queues will not have :cpp:member:`m_maxPackets` initialized to
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100 packets, as defined in the :cpp:func:`DropTailQueue::GetTypeId ()`
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newly created queues will not have :cpp:member:`m_maxSize` initialized to
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0 packets, as defined in the :cpp:func:`QueueBase::GetTypeId ()`
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function, but to 80 packets, because of what we did above with
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default values.::
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@@ -411,7 +458,7 @@ default values.::
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Ptr<PointToPointNetDevice> net0 = CreateObject<PointToPointNetDevice> ();
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n0->AddDevice (net0);
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Ptr<Queue> q = CreateObject<DropTailQueue> ();
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Ptr<Queue<Packet> > q = CreateObject<DropTailQueue<Packet> > ();
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net0->AddQueue(q);
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At this point, we have created a single :cpp:class:`Node` (``n0``)
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@@ -460,10 +507,9 @@ class instances *to be created in the future:*
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But what if you've already created an instance, and you want
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to change the value of the attribute? In this example, how can we
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manipulate the :cpp:member:`m_maxPackets` value of the already instantiated
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manipulate the :cpp:member:`m_maxSize` value of the already instantiated
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:cpp:class:`DropTailQueue`? Here are various ways to do that.
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Changing Values
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+++++++++++++++
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@@ -481,39 +527,47 @@ First, we observe that we can get a pointer to the (base class)
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:cpp:class:`PointToPointNetDevice` attributes, where it is called
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``"TxQueue"``::
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PointerValue tmp;
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net0->GetAttribute ("TxQueue", tmp);
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Ptr<Object> txQueue = tmp.GetObject ();
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PointerValue ptr;
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net0->GetAttribute ("TxQueue", ptr);
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Ptr<Queue<Packet> > txQueue = ptr.Get<Queue<Packet> > ();
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Using the :cpp:func:`GetObject ()` function, we can perform a safe downcast
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to a :cpp:class:`DropTailQueue`, where ``"MaxPackets"`` is an attribute::
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to a :cpp:class:`DropTailQueue`. The `NS_ASSERT` checks that the pointer is
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valid.
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Ptr<DropTailQueue> dtq = txQueue->GetObject <DropTailQueue> ();
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::
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Ptr<DropTailQueue<Packet> > dtq = txQueue->GetObject <DropTailQueue<Packet> > ();
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NS_ASSERT (dtq != 0);
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Next, we can get the value of an attribute on this queue. We have introduced
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wrapper ``Value`` classes for the underlying data types, similar
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to Java wrappers around these types, since the attribute system stores values
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serialized to strings, and not disparate types. Here, the attribute value
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is assigned to a :cpp:class:`UintegerValue`, and the :cpp:func:`Get ()`
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method on this value produces the (unwrapped) ``uint32_t``.::
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is assigned to a :cpp:class:`QueueSizeValue`, and the :cpp:func:`Get ()`
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method on this value produces the (unwrapped) ``QueueSize``. That is,
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the variable `limit` is written into by the GetAttribute method.::
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UintegerValue limit;
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dtq->GetAttribute ("MaxPackets", limit);
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NS_LOG_INFO ("1. dtq limit: " << limit.Get () << " packets");
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QueueSizeValue limit;
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dtq->GetAttribute ("MaxSize", limit);
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NS_LOG_INFO ("1. dtq limit: " << limit.Get ());
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Note that the above downcast is not really needed; we could have gotten
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the attribute value directly from ``txQueue``, which is an :cpp:class:`Object`::
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the attribute value directly from ``txQueue``::
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txQueue->GetAttribute ("MaxPackets", limit);
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NS_LOG_INFO ("2. txQueue limit: " << limit.Get () << " packets");
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txQueue->GetAttribute ("MaxSize", limit);
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NS_LOG_INFO ("2. txQueue limit: " << limit.Get ());
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Now, let's set it to another value (60 packets)::
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Now, let's set it to another value (60 packets). Let's also make
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use of the StringValue shorthand notation to set the size by
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passing in a string (the string must be a positive integer suffixed
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by either the `p` or `b` character).
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txQueue->SetAttribute("MaxPackets", UintegerValue (60));
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txQueue->GetAttribute ("MaxPackets", limit);
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NS_LOG_INFO ("3. txQueue limit changed: " << limit.Get () << " packets");
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::
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txQueue->SetAttribute ("MaxSize", StringValue ("60p"));
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txQueue->GetAttribute ("MaxSize", limit);
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NS_LOG_INFO ("3. txQueue limit changed: " << limit.Get ());
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Config Namespace Path
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=====================
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@@ -523,11 +577,11 @@ namespace. Here, this attribute resides on a known path in this namespace; this
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approach is useful if one doesn't have access to the underlying pointers and
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would like to configure a specific attribute with a single statement.::
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Config::Set ("/NodeList/0/DeviceList/0/TxQueue/MaxPackets",
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UintegerValue (25));
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txQueue->GetAttribute ("MaxPackets", limit);
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Config::Set ("/NodeList/0/DeviceList/0/TxQueue/MaxSize",
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StringValue ("25p"));
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txQueue->GetAttribute ("MaxSize", limit);
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NS_LOG_INFO ("4. txQueue limit changed through namespace: "
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<< limit.Get () << " packets");
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<< limit.Get ());
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The configuration path often has the form of
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``".../<container name>/<index>/.../<attribute>/<attribute>"``
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@@ -535,18 +589,28 @@ to refer to a specific instance by index of an object in the container.
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In this case the first container is the list of all :cpp:class:`Node`\s;
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the second container is the list of all :cpp:class:`NetDevice`\s on
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the chosen :cpp:class:`Node`. Finally, the configuration path usually
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ends with a succession of member attributes, in this case the ``"MaxPackets"``
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ends with a succession of member attributes, in this case the ``"MaxSize"``
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attribute of the ``"TxQueue"`` of the chosen :cpp:class:`NetDevice`.
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We could have also used wildcards to set this value for all nodes and all net
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devices (which in this simple example has the same effect as the previous
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:cpp:func:`Config::Set ()`)::
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Config::Set ("/NodeList/*/DeviceList/*/TxQueue/MaxPackets",
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UintegerValue (15));
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txQueue->GetAttribute ("MaxPackets", limit);
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Config::Set ("/NodeList/*/DeviceList/*/TxQueue/MaxSize",
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StringValue ("15p"));
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txQueue->GetAttribute ("MaxSize", limit);
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NS_LOG_INFO ("5. txQueue limit changed through wildcarded namespace: "
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<< limit.Get () << " packets");
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<< limit.Get ());
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If you run this program from the command line, you should see the following
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output corresponding to the steps we took above::
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$ ./waf --run main-attribute-value
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1. dtq limit: 80p
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2. txQueue limit: 80p
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3. txQueue limit changed: 60p
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4. txQueue limit changed through namespace: 25p
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5. txQueue limit changed through wildcarded namespace: 15p
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Object Name Service
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===================
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@@ -936,32 +1000,37 @@ After running, you can open the ``output-attributes.txt`` file and see:
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.. sourcecode:: text
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default ns3::RealtimeSimulatorImpl::SynchronizationMode "BestEffort"
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default ns3::RealtimeSimulatorImpl::HardLimit "+100000000.0ns"
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default ns3::PcapFileWrapper::CaptureSize "65535"
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default ns3::PacketSocket::RcvBufSize "131072"
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...
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default ns3::ErrorModel::IsEnabled "true"
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default ns3::RateErrorModel::ErrorUnit "EU_BYTE"
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default ns3::RateErrorModel::ErrorUnit "ERROR_UNIT_BYTE"
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default ns3::RateErrorModel::ErrorRate "0"
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default ns3::RateErrorModel::RanVar "Uniform:0:1"
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default ns3::DropTailQueue::Mode "Packets"
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default ns3::DropTailQueue::MaxPackets "100"
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default ns3::DropTailQueue::MaxBytes "6553500"
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default ns3::Application::StartTime "+0.0ns"
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default ns3::Application::StopTime "+0.0ns"
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default ns3::RateErrorModel::RanVar "ns3::UniformRandomVariable[Min=0.0|Max=1.0]"
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default ns3::BurstErrorModel::ErrorRate "0"
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default ns3::BurstErrorModel::BurstStart "ns3::UniformRandomVariable[Min=0.0|Max=1.0]"
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default ns3::BurstErrorModel::BurstSize "ns3::UniformRandomVariable[Min=1|Max=4]"
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default ns3::PacketSocket::RcvBufSize "131072"
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default ns3::PcapFileWrapper::CaptureSize "65535"
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default ns3::PcapFileWrapper::NanosecMode "false"
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default ns3::SimpleNetDevice::PointToPointMode "false"
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default ns3::SimpleNetDevice::TxQueue "ns3::DropTailQueue<Packet>"
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default ns3::SimpleNetDevice::DataRate "0bps"
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default ns3::PacketSocketClient::MaxPackets "100"
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default ns3::PacketSocketClient::Interval "+1000000000.0ns"
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default ns3::PacketSocketClient::PacketSize "1024"
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default ns3::PacketSocketClient::Priority "0"
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default ns3::ConfigStore::Mode "Save"
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default ns3::ConfigStore::Filename "output-attributes.txt"
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default ns3::ConfigStore::FileFormat "RawText"
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default ns3::ConfigExample::TestInt16 "-5"
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global RngSeed "1"
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global RngRun "1"
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global SimulatorImplementationType "ns3::DefaultSimulatorImpl"
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global SchedulerType "ns3::MapScheduler"
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global RngSeed "1"
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global RngRun "1"
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global ChecksumEnabled "false"
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value /$ns3::ConfigExample/TestInt16 "-3"
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In the above, all of the default values for attributes for the core
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module are shown. Then, all the values for the |ns3| global values
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In the above, several of the default values for attributes for the core
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and network modules are shown. Then, all the values for the |ns3| global values
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are recorded. Finally, the value of the instance of :cpp:class:`ConfigExample`
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that was rooted in the configuration namespace is shown. In a real
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|ns3| program, many more models, attributes, and defaults would be shown.
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@@ -972,27 +1041,31 @@ An XML version also exists in ``output-attributes.xml``:
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<?xml version="1.0" encoding="UTF-8"?>
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<ns3>
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<default name="ns3::RealtimeSimulatorImpl::SynchronizationMode" value="BestEffort"/>
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<default name="ns3::RealtimeSimulatorImpl::HardLimit" value="+100000000.0ns"/>
|
||||
<default name="ns3::PcapFileWrapper::CaptureSize" value="65535"/>
|
||||
<default name="ns3::PacketSocket::RcvBufSize" value="131072"/>
|
||||
<default name="ns3::ErrorModel::IsEnabled" value="true"/>
|
||||
<default name="ns3::RateErrorModel::ErrorUnit" value="EU_BYTE"/>
|
||||
<default name="ns3::RateErrorModel::ErrorUnit" value="ERROR_UNIT_BYTE"/>
|
||||
<default name="ns3::RateErrorModel::ErrorRate" value="0"/>
|
||||
<default name="ns3::RateErrorModel::RanVar" value="Uniform:0:1"/>
|
||||
<default name="ns3::DropTailQueue::Mode" value="Packets"/>
|
||||
<default name="ns3::DropTailQueue::MaxPackets" value="100"/>
|
||||
<default name="ns3::DropTailQueue::MaxBytes" value="6553500"/>
|
||||
<default name="ns3::Application::StartTime" value="+0.0ns"/>
|
||||
<default name="ns3::Application::StopTime" value="+0.0ns"/>
|
||||
<default name="ns3::RateErrorModel::RanVar" value="ns3::UniformRandomVariable[Min=0.0|Max=1.0]"/>
|
||||
<default name="ns3::BurstErrorModel::ErrorRate" value="0"/>
|
||||
<default name="ns3::BurstErrorModel::BurstStart" value="ns3::UniformRandomVariable[Min=0.0|Max=1.0]"/>
|
||||
<default name="ns3::BurstErrorModel::BurstSize" value="ns3::UniformRandomVariable[Min=1|Max=4]"/>
|
||||
<default name="ns3::PacketSocket::RcvBufSize" value="131072"/>
|
||||
<default name="ns3::PcapFileWrapper::CaptureSize" value="65535"/>
|
||||
<default name="ns3::PcapFileWrapper::NanosecMode" value="false"/>
|
||||
<default name="ns3::SimpleNetDevice::PointToPointMode" value="false"/>
|
||||
<default name="ns3::SimpleNetDevice::TxQueue" value="ns3::DropTailQueue<Packet>"/>
|
||||
<default name="ns3::SimpleNetDevice::DataRate" value="0bps"/>
|
||||
<default name="ns3::PacketSocketClient::MaxPackets" value="100"/>
|
||||
<default name="ns3::PacketSocketClient::Interval" value="+1000000000.0ns"/>
|
||||
<default name="ns3::PacketSocketClient::PacketSize" value="1024"/>
|
||||
<default name="ns3::PacketSocketClient::Priority" value="0"/>
|
||||
<default name="ns3::ConfigStore::Mode" value="Save"/>
|
||||
<default name="ns3::ConfigStore::Filename" value="output-attributes.xml"/>
|
||||
<default name="ns3::ConfigStore::FileFormat" value="Xml"/>
|
||||
<default name="ns3::ConfigExample::TestInt16" value="-5"/>
|
||||
<global name="RngSeed" value="1"/>
|
||||
<global name="RngRun" value="1"/>
|
||||
<global name="SimulatorImplementationType" value="ns3::DefaultSimulatorImpl"/>
|
||||
<global name="SchedulerType" value="ns3::MapScheduler"/>
|
||||
<global name="RngSeed" value="1"/>
|
||||
<global name="RngRun" value="1"/>
|
||||
<global name="ChecksumEnabled" value="false"/>
|
||||
<value path="/$ns3::ConfigExample/TestInt16" value="-3"/>
|
||||
</ns3>
|
||||
@@ -1122,10 +1195,3 @@ Now, when you run the script, a GUI should pop up, allowing you to open menus of
|
||||
attributes on different nodes/objects, and then launch the simulation execution
|
||||
when you are done.
|
||||
|
||||
Future work
|
||||
+++++++++++
|
||||
There are a couple of possible improvements:
|
||||
|
||||
* Save a unique version number with date and time at start of file.
|
||||
* Save rng initial seed somewhere.
|
||||
* Make each RandomVariable serialize its own initial seed and re-read it later.
|
||||
|
||||
@@ -38,8 +38,8 @@ NS_LOG_COMPONENT_DEFINE ("AttributeValueSample");
|
||||
|
||||
//
|
||||
// This is a basic example of how to use the attribute system to
|
||||
// set and get a value in the underlying system; namely, an unsigned
|
||||
// integer of the maximum number of packets in a queue
|
||||
// set and get a value in the underlying system; namely, the maximum
|
||||
// size of the FIFO queue in the PointToPointNetDevice
|
||||
//
|
||||
|
||||
int
|
||||
@@ -47,15 +47,25 @@ main (int argc, char *argv[])
|
||||
{
|
||||
LogComponentEnable ("AttributeValueSample", LOG_LEVEL_INFO);
|
||||
|
||||
// By default, the MaxSize attribute has a value of 100 packets
|
||||
// (this default can be observed in the function DropTailQueue::GetTypeId)
|
||||
// Queues in ns-3 are objects that hold items (other objects) in
|
||||
// a queue structure. The C++ implementation uses templates to
|
||||
// allow queues to hold various types of items, but the most
|
||||
// common is a pointer to a packet (Ptr<Packet>).
|
||||
//
|
||||
// The maximum queue size can either be enforced in bytes ('b') or
|
||||
// packets ('p'). A special type called the ns3::QueueSize can
|
||||
// hold queue size values in either unit (bytes or packets). The
|
||||
// queue base class ns3::QueueBase has a MaxSize attribute that can
|
||||
// be set to a QueueSize.
|
||||
|
||||
// By default, the MaxSize attribute has a value of 100 packets ('100p')
|
||||
// (this default can be observed in the function QueueBase::GetTypeId)
|
||||
//
|
||||
// Here, we set it to 80 packets. We could use one of two value types:
|
||||
// a string-based value or a QueueSizeValue value
|
||||
Config::SetDefault ("ns3::QueueBase::MaxSize", StringValue ("80p"));
|
||||
// The below function call is redundant
|
||||
Config::SetDefault ("ns3::QueueBase::MaxSize",
|
||||
QueueSizeValue (QueueSize (QueueSizeUnit::PACKETS, 80)));
|
||||
Config::SetDefault ("ns3::QueueBase::MaxSize", QueueSizeValue (QueueSize (QueueSizeUnit::PACKETS, 80)));
|
||||
|
||||
// Allow the user to override any of the defaults and the above
|
||||
// SetDefaults() at run-time, via command-line arguments
|
||||
@@ -97,7 +107,7 @@ main (int argc, char *argv[])
|
||||
Ptr<Queue<Packet> > txQueue = ptr.Get<Queue<Packet> > ();
|
||||
|
||||
// Using the GetObject function, we can perform a safe downcast
|
||||
// to a DropTailQueue, where MaxSize is a member
|
||||
// to a DropTailQueue
|
||||
Ptr<DropTailQueue<Packet> > dtq = txQueue->GetObject <DropTailQueue<Packet> > ();
|
||||
NS_ASSERT (dtq);
|
||||
|
||||
@@ -105,22 +115,25 @@ main (int argc, char *argv[])
|
||||
// We have introduced wrapper "Value" classes for the underlying
|
||||
// data types, similar to Java wrappers around these types, since
|
||||
// the attribute system stores values and not disparate types.
|
||||
// Here, the attribute value is assigned to a Uinteger, and
|
||||
// the Get() method on this value produces the (unwrapped) uint32_t.
|
||||
// Here, the attribute value is assigned to a QueueSizeValue, and
|
||||
// the Get() method on this value produces the (unwrapped) QueueSize.
|
||||
QueueSizeValue limit;
|
||||
dtq->GetAttribute ("MaxSize", limit);
|
||||
NS_LOG_INFO ("1. dtq limit: " << limit.Get ().GetValue () << " packets");
|
||||
NS_LOG_INFO ("1. dtq limit: " << limit.Get ());
|
||||
|
||||
// Note that the above downcast is not really needed; we could have
|
||||
// done the same using the Ptr<Queue> even though the attribute
|
||||
// is a member of the subclass
|
||||
txQueue->GetAttribute ("MaxSize", limit);
|
||||
NS_LOG_INFO ("2. txQueue limit: " << limit.Get () << " packets");
|
||||
NS_LOG_INFO ("2. txQueue limit: " << limit.Get ());
|
||||
|
||||
// Now, let's set it to another value (60 packets)
|
||||
// Now, let's set it to another value (60 packets). Let's also make
|
||||
// use of the StringValue shorthand notation to set the size by
|
||||
// passing in a string (the string must be a positive integer suffixed
|
||||
// by either the 'p' or 'b' character).
|
||||
txQueue->SetAttribute ("MaxSize", StringValue ("60p"));
|
||||
txQueue->GetAttribute ("MaxSize", limit);
|
||||
NS_LOG_INFO ("3. txQueue limit changed: " << limit.Get () << " packets");
|
||||
NS_LOG_INFO ("3. txQueue limit changed: " << limit.Get ());
|
||||
|
||||
// 2. Namespace-based access
|
||||
//
|
||||
@@ -132,7 +145,7 @@ main (int argc, char *argv[])
|
||||
Config::Set ("/NodeList/0/DeviceList/0/TxQueue/MaxSize", StringValue ("25p"));
|
||||
txQueue->GetAttribute ("MaxSize", limit);
|
||||
NS_LOG_INFO ("4. txQueue limit changed through namespace: " <<
|
||||
limit.Get () << " packets");
|
||||
limit.Get ());
|
||||
|
||||
// we could have also used wildcards to set this value for all nodes
|
||||
// and all net devices (which in this simple example has the same
|
||||
@@ -140,7 +153,7 @@ main (int argc, char *argv[])
|
||||
Config::Set ("/NodeList/*/DeviceList/*/TxQueue/MaxSize", StringValue ("15p"));
|
||||
txQueue->GetAttribute ("MaxSize", limit);
|
||||
NS_LOG_INFO ("5. txQueue limit changed through wildcarded namespace: " <<
|
||||
limit.Get () << " packets");
|
||||
limit.Get ());
|
||||
|
||||
Simulator::Destroy ();
|
||||
}
|
||||
|
||||
20
src/point-to-point/test/examples-to-run.py
Normal file
20
src/point-to-point/test/examples-to-run.py
Normal file
@@ -0,0 +1,20 @@
|
||||
#! /usr/bin/env python
|
||||
## -*- Mode: python; py-indent-offset: 4; indent-tabs-mode: nil; coding: utf-8; -*-
|
||||
|
||||
# A list of C++ examples to run in order to ensure that they remain
|
||||
# buildable and runnable over time. Each tuple in the list contains
|
||||
#
|
||||
# (example_name, do_run, do_valgrind_run).
|
||||
#
|
||||
# See test.py for more information.
|
||||
cpp_examples = [
|
||||
("main-attribute-value", "True", "True"),
|
||||
]
|
||||
|
||||
# A list of Python examples to run in order to ensure that they remain
|
||||
# runnable over time. Each tuple in the list contains
|
||||
#
|
||||
# (example_name, do_run).
|
||||
#
|
||||
# See test.py for more information.
|
||||
python_examples = []
|
||||
Reference in New Issue
Block a user