--- a/src/common/trace-root.h Thu Sep 06 15:18:14 2007 +0100
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,335 +0,0 @@
-/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
-/*
- * Copyright (c) 2007 INRIA
- * All rights reserved.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation;
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- *
- * Author: Mathieu Lacage <mathieu.lacage@sophia.inria.fr>
- */
-#ifndef TRACE_ROOT_H
-#define TRACE_ROOT_H
-
-#include <string>
-#include "ns3/callback.h"
-
-/**
- * \defgroup lowleveltracing Low-level tracing
- *
- * This low-level API is built around a few concepts:
- * - There can be any number of trace source objects. Each trace source
- * object can generate any number of trace events. The current
- * trace source objects are: ns3::CallbackTraceSourceSource, ns3::UVTraceSource,
- * ns3::SVTraceSource, and, ns3::FVTraceSource.
- * - Each trace source can be connected to any number of trace sinks.
- * A trace sink is a ns3::Callback with a very special signature. Its
- * first argument is always a ns3::TraceContext.
- * - Every trace source is uniquely identified by a ns3::TraceContext. Every
- * trace sink can query a ns3::TraceContext for information. This allows
- * a trace sink which is connected to multiple trace sources to identify
- * from which source each event is coming from.
- *
- * To define new trace sources, a model author needs to instante one trace source
- * object for each kind of tracing event he wants to export. The trace source objects
- * currently defined are:
- * - ns3::CallbackTraceSourceSource: this trace source can be used to convey any kind of
- * trace event to the user. It is a functor, that is, it is a variable
- * which behaves like a function which will forward every event to every
- * connected trace sink (i.e., ns3::Callback). This trace source takes
- * up to four arguments and forwards these 4 arguments together with the
- * ns3::TraceContext which identifies this trace source to the connected
- * trace sinks.
- * - ns3::UVTraceSource: this trace source is used to convey key state variable
- * changes to the user. It behaves like a normal integer unsigned variable:
- * you can apply every normal arithmetic operator to it. It will forward
- * every change in the value of the variable back to every connected trace
- * sink by providing a TraceContext, the old value and the new value.
- * - ns3::SVTraceSource: this is the signed integer equivalent of
- * ns3::UVTraceSource.
- * - ns3::FVTraceSource: this is the floating point equivalent of
- * ns3::UVTraceSource and ns3::SVTraceSource.
- *
- * For example, to define a trace source which notifies you of a new packet
- * being transmitted, you would have to:
- * \code
- * class MyModel
- * {
- * public:
- * void Tx (Packet const &p);
- * private:
- * CallbackTraceSource<Packet const &> m_txTrace;
- * };
- *
- * void
- * MyModel::Tx (Packet const &p)
- * {
- * // trace packet tx event.
- * m_txTrace (p);
- * // ... send the packet for real.
- * }
- * \endcode
- *
- * Once the model author has instantiated these objects and has wired them
- * in his simulation code (that is, he calls them wherever he wants to trigger
- * a trace event), he needs to make these trace sources available to users
- * to allow them to connect any number of trace sources to any number
- * of user trace sinks. While it would be possible to make each model
- * export directly each of his trace source instances and request users to
- * invoke a source->Connect (callback) method to perform the connection
- * explicitely, it was felt that this was a bit cumbersome to do.
- *
- * As such, the ``connection'' between a set of sources and a sink is
- * performed through a third-party class, the TraceResolver, which
- * can be used to automate the connection of multiple matching trace sources
- * to a single sink. This TraceResolver works by defining a hierarchical
- * tracing namespace: the root of this namespace is accessed through the
- * ns3::TraceRoot class. The namespace is represented as a string made of
- * multiple elements, each of which is separated from the other elements
- * by the '/' character. A namespace string always starts with a '/'.
- *
- * By default, the current simulation models provide a '/nodes' tracing root.
- * This '/nodes' namespace is structured as follows:
- * \code
- * /nodes/n/arp
- * /nodes/n/udp
- * /nodes/n/ipv4
- * /tx
- * /rx
- * /drop
- * /interfaces/n/netdevice
- * /queue/
- * /enque
- * /deque
- * /drop
- * \endcode
- *
- * The 'n' element which follows the /nodes and /interfaces namespace elements
- * identify a specific node and interface through their index within the
- * ns3::NodeList and ns3::Ipv4 objects respectively.
- *
- * To connect a trace sink to a trace source identified by a namespace string,
- * a user can call the ns3::TraceRoot::Connect method (the ns3::TraceRoot::Disconnect
- * method does the symmetric operation). This connection method can accept
- * fully-detailed namespace strings but it can also perform pattern matching
- * on the user-provided namespace strings to connect multiple trace sources
- * to a single trace sink in a single connection operation.
- *
- * The syntax of the pattern matching rules are loosely based on regular
- * expressions:
- * - the '*' character matches every element
- * - the (a|b) construct matches element 'a' or 'b'
- * - the [ss-ee] construct matches all numerical values which belong
- * to the interval which includes ss and ee
- *
- * For example, the user could use the following to connect a single sink
- * to the ipv4 tx, rx, and drop trace events:
- *
- * \code
- * void MyTraceSink (TraceContext const &context, Packet &packet);
- * TraceRoot::Connect ("/nodes/ * /ipv4/ *", MakeCallback (&MyTraceSink));
- * \endcode
- *
- * Of course, this code would work only if the signature of the trace sink
- * is exactly equal to the signature of all the trace sources which match
- * the namespace string (if one of the matching trace source does not match
- * exactly, a fatal error will be triggered at runtime during the connection
- * process). The ns3::TraceContext extra argument contains
- * information on where the trace source is located in the namespace tree.
- * In that example, if there are multiple nodes in this scenario, each
- * call to the MyTraceSink function would receive a different TraceContext,
- * each of which would contain a different NodeList::NodeIndex object.
- *
- * It is important to understand exactly what an ns3::TraceContext
- * is. It is a container for a number of type instances. Each instance of
- * a ns3::TraceContext contains one and only one instance of a given type.
- * ns3::TraceContext::Add can be called to add a type instance into a
- * TraceContext instance and ns3::TraceContext::Get can be called to get
- * a copy of a type instance stored into the ns3::TraceContext. If ::Get
- * cannot retrieve the requested type, a fatal error is triggered at
- * runtime. The values stored into an ns3::TraceContext attached to a
- * trace source are automatically determined during the namespace
- * resolution process. To retrieve a value from a ns3::TraceContext, the
- * code can be as simple as this:
- * \code
- * void MyTraceSink (TraceContext const &context, Packet &packet)
- * {
- * NodeList::NodeIndex index;
- * context.Get (index);
- * std::cout << "node id=" << NodeList::GetNode (index)->GetId () << std::endl;
- * }
- * \endcode
- *
- * The hierarchical global namespace described here is not implemented
- * in a single central location: it was felt that doing this would make
- * it too hard to introduce user-specific models which could hook
- * automatically into the overal tracing system. If the tracing
- * namespace was implemented in a single central location, every model
- * author would have had to modify this central component to make
- * his own model available to trace users.
- *
- * Instead, the handling of the namespace is distributed across every relevant
- * model: every model implements only the part of the namespace it is
- * really responsible for. To do this, every model is expected
- * to provide an instance of a TraceResolver whose
- * responsability is to recursively provide access to the trace sources
- * defined in its model. Each TraceResolver instance should be a subclass
- * of the TraceResolver base class which implements either the DoLookup
- * or the DoConnect and DoDisconnect methods. Because implementing these
- * methods can be a bit tedious, our tracing framework provides a number
- * of helper template classes which should save the model author from
- * having to implement his own in most cases:
- * - ns3::CompositeTraceResolver: this subclass of ns3::TraceResolver can
- * be used to aggregate together multiple trace sources and multiple other
- * ns3::TraceResolver instances.
- * - ns3::ArrayTraceResolver: this subclass of ns3::TraceResolver can be
- * used to match any number of elements within an array where every element
- * is identified by its index.
- *
- * Once you can instantiate your own ns3::TraceResolver object instance, you
- * have to hook it up into the global namespace. There are two ways to do this:
- * - you can hook your ns3::TraceResolver creation method as a new trace
- * root by using the ns3::TraceRoot::Register method
- * - you can hook your new ns3::TraceResolver creation method into the
- * container of your model. This step will obvsiouly depend on which model
- * contains your own model but, if you wrote a new l3 protocol, all you
- * would have to do to hook into your container L3Demux class is to implement
- * the pure virtual method inherited from the L3Protocol class whose name is
- * ns3::L3protocol::CreateTraceResolver.
- *
- * So, in most cases, exporting a model's trace sources is a matter of
- * implementing a method CreateTraceResolver as shown below:
- * \code
- * class MyModel
- * {
- * public:
- * enum TraceType {
- * TX,
- * RX,
- * ...
- * };
- * TraceResolver *CreateTraceResolver (TraceContext const &context);
- * void Tx (Packet const &p);
- * private:
- * CallbackTraceSource<Packet const &> m_txTrace;
- * };
- *
- * TraceResolver *
- * MyModel::CreateTraceResolver (TraceContext const &context)
- * {
- * CompositeTraceResolver *resolver = new CompositeTraceResolver (context);
- * resolver->Add ("tx", m_txTrace, MyModel::TX);
- * return resolver;
- * }
- * void
- * MyModel::Tx (Packet const &p)
- * {
- * m_txTrace (p);
- * }
- * \endcode
- *
- * If you really want to have fun and implement your own ns3::TraceResolver
- * subclass, you need to understand the basic Connection and Disconnection
- * algorithm. The code of that algorithm is wholy contained in the
- * ns3::TraceResolver::Connect and ns3::TraceResolver::Disconnect methods.
- * The idea is that we recursively parse the input namespace string by removing
- * the first namespace element. This element is 'resolved' is calling
- * the ns3::TraceResolver::DoLookup method which returns a list of
- * TraceResolver instances. Each of the returned TraceResolver instance is
- * then given what is left of the namespace by calling ns3::TraceResolver::Connect
- * until the last namespace element is processed. At this point, we invoke
- * the ns3::TraceResolver::DoConnect or ns3::TraceResolver::DoDisconnect
- * methods to break the recursion. A good way to understand this algorithm
- * is to trace its behavior. Let's say that you want to connect to
- * '/nodes/ * /ipv4/interfaces/ * /netdevice/queue/ *'. It would generate
- * the following call traces:
- *
- * \code
- * TraceRoot::Connect ("/nodes/ * /ipv4/interfaces/ * /netdevice/queue/ *", callback);
- * traceContext = TraceContext ();
- * rootResolver = CompositeTraceResolver (traceContext);
- * rootResolver->Connect ("/nodes/ * /ipv4/interfaces/ * /netdevice/queue/ *", callback);
- * resolver = CompositeTraceResolver::DoLookup ("nodes");
- * return NodeList::CreateTraceResolver (GetContext ());
- * return ArrayTraceResolver (context);
- * resolver->Connect ("/ * /ipv4/interfaces/ * /netdevice/queue/ *", callback);
- * ArrayTraceResolver::DoLookup ("*");
- * for (i = 0; i < n_nodes; i++)
- * resolver = nodes[i]->CreateTraceResolver (GetContext ());
- * return CompositeTraceResolver (context);
- * resolvers.add (resolver);
- * return resolvers;
- * for resolver in (resolvers)
- * resolver->Connect ("/ipv4/interfaces/ * /netdevice/queue/ *", callback);
- * CompositeTraceResolver::DoLookup ("ipv4");
- * resolver = ipv4->CreateTraceResolver (GetContext ());
- * return CompositeTraceResolver (context);
- * return resolver;
- * resolver->Connect ("/interfaces/ * /netdevice/queue/ *", callback);
- * CompositeTraceResolver::DoLookup ("interfaces");
- * resolver = ArrayTraceResolver (GetContext ());
- * resolver->Connect ("/ * /netdevice/queue/ *", callback);
- * ArrayTraceResolver::DoLookup ("*");
- * for (i = 0; i < n_interfaces; i++)
- * resolver = interfaces[i]->CreateTraceResolver (GetContext ());
- * return CompositeTraceResolver ()
- * resolvers.add (resolver);
- * return resolvers;
- * resolver->Connect ("/netdevice/queue/ *", callback);
- * CompositeTraceResolver::DoLookup ("netdevice");
- * resolver = NetDevice::CreateTraceResolver (GetContext ());
- * return CompositeTraceResolver ();
- * return resolver;
- * resolver->Connect ("/queue/ *", callback);
- * CompositeTraceResolver::DoLookup ("queue");
- * resolver = Queue::CreateTraceResolver (GetContext ());
- * return CompositeTraceResolver ();
- * return resolver
- * resolver->Connect ("*", callback);
- * CompositeTraceResolver::DoLookup ("*");
- * for match in (matches)
- * resolver = TerminalTraceResolver ("match");
- * resolvers.add (resolver)
- * return resolvers;
- * for resolver in (resolvers)
- * TerminalTraceResolver->DoConnect (callback);
- * \endcode
- */
-
-namespace ns3 {
-
-class CompositeTraceResolver;
-class TraceResolver;
-class TraceContext;
-class CallbackBase;
-
-/**
- * \brief The main class used to access tracing functionality for
- * a user.
- *
- * \ingroup lowleveltracing
- */
-class TraceRoot
-{
-public:
- static void Connect (std::string path, CallbackBase const &cb);
- static void Disconnect (std::string path, CallbackBase const &cb);
- static void Register (std::string name,
- Callback<TraceResolver *,TraceContext const &> createResolver);
-private:
- static CompositeTraceResolver *GetComposite (void);
-};
-
-}// namespace ns3
-
-#endif /* TRACE_ROOT_H */