A Discrete-Event Network Simulator
API
wall-clock-synchronizer.h
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18 
19 #ifndef WALL_CLOCK_CLOCK_SYNCHRONIZER_H
20 #define WALL_CLOCK_CLOCK_SYNCHRONIZER_H
21 
22 #include "system-condition.h"
23 #include "synchronizer.h"
24 
31 namespace ns3 {
32 
71 {
72 public:
77  static TypeId GetTypeId (void);
78 
82  virtual ~WallClockSynchronizer ();
83 
85  static const uint64_t US_PER_NS = (uint64_t)1000;
87  static const uint64_t US_PER_SEC = (uint64_t)1000000;
89  static const uint64_t NS_PER_SEC = (uint64_t)1000000000;
90 
91 protected:
104  bool SpinWait (uint64_t ns);
128  bool SleepWait (uint64_t ns);
129 
130  // Inherited from Synchronizer
131  virtual void DoSetOrigin (uint64_t ns);
132  virtual bool DoRealtime (void);
133  virtual uint64_t DoGetCurrentRealtime (void);
134  virtual bool DoSynchronize (uint64_t nsCurrent, uint64_t nsDelay);
135  virtual void DoSignal (void);
136  virtual void DoSetCondition (bool cond);
137  virtual int64_t DoGetDrift (uint64_t ns);
138  virtual void DoEventStart (void);
139  virtual uint64_t DoEventEnd (void);
140 
150  uint64_t DriftCorrect (uint64_t nsNow, uint64_t nsDelay);
151 
157  uint64_t GetRealtime (void);
163  uint64_t GetNormalizedRealtime (void);
164 
171  void NsToTimeval (int64_t ns, struct timeval *tv);
178  uint64_t TimevalToNs (struct timeval *tv);
179 
187  void TimevalAdd (
188  struct timeval *tv1,
189  struct timeval *tv2,
190  struct timeval *result);
191 
193  uint64_t m_jiffy;
195  uint64_t m_nsEventStart;
196 
199 };
200 
201 } // namespace ns3
202 
203 #endif /* WALL_CLOCK_SYNCHRONIZER_H */
uint64_t m_jiffy
Size of the system clock tick, as reported by clock_getres, in ns.
ns3::SystemCondition declaration.
uint64_t TimevalToNs(struct timeval *tv)
Convert a timeval to absolute time, in ns.
A class which provides a relatively platform-independent conditional-wait thread synchronization prim...
static const uint64_t NS_PER_SEC
Conversion constant between ns and s.
uint64_t m_nsEventStart
Time recorded by DoEventStart.
bool SleepWait(uint64_t ns)
Put our process to sleep for some number of nanoseconds.
static const uint64_t US_PER_NS
Conversion constant between μs and ns.
uint64_t GetRealtime(void)
Get the current absolute real time (in ns since the epoch).
virtual int64_t DoGetDrift(uint64_t ns)
Get the drift between the real time clock used to synchronize the simulation and the current simulati...
virtual bool DoRealtime(void)
Return true if this synchronizer is actually synchronizing to a realtime clock.
virtual uint64_t DoGetCurrentRealtime(void)
Retrieve the value of the origin of the underlying normalized wall clock time in Time resolution unit...
virtual bool DoSynchronize(uint64_t nsCurrent, uint64_t nsDelay)
Wait until the real time is in sync with the specified simulation time.
Every class exported by the ns3 library is enclosed in the ns3 namespace.
virtual ~WallClockSynchronizer()
Destructor.
Base class used for synchronizing the simulation events to some real time "wall clock.".
Definition: synchronizer.h:51
virtual void DoSetOrigin(uint64_t ns)
Establish a correspondence between a simulation time and a wall-clock (real) time.
static const uint64_t US_PER_SEC
Conversion constant between μs and seconds.
ns3::Synchronizer declaration.
virtual void DoEventStart(void)
Record the normalized real time at which the current event is starting execution. ...
virtual void DoSetCondition(bool cond)
Set the condition variable to tell a possible simulator thread waiting in the Synchronize method that...
void NsToTimeval(int64_t ns, struct timeval *tv)
Convert an absolute time in ns to a timeval.
static TypeId GetTypeId(void)
Get the registered TypeId for this class.
void TimevalAdd(struct timeval *tv1, struct timeval *tv2, struct timeval *result)
Add two timeval.
SystemCondition m_condition
Thread synchronizer.
Class used for synchronizing the simulation events to a real-time "wall clock" using Posix clock func...
a unique identifier for an interface.
Definition: type-id.h:58
uint64_t GetNormalizedRealtime(void)
Get the current normalized real time, in ns.
bool SpinWait(uint64_t ns)
Do a busy-wait until the normalized realtime equals the argument or the condition variable becomes tr...
virtual void DoSignal(void)
Tell a possible simulator thread waiting in the DoSynchronize method that an event has happened which...
virtual uint64_t DoEventEnd(void)
Return the amount of real time elapsed since the last call to EventStart.
uint64_t DriftCorrect(uint64_t nsNow, uint64_t nsDelay)
Compute a correction to the nominal delay to account for realtime drift since the last DoSynchronize...