A class which provides a simple way to implement a Critical Section. More...

#include "system-mutex.h"

Collaboration diagram for ns3::CriticalSection:

Public Member Functions
	CriticalSection (SystemMutex &mutex)
	Construct with the required SystemMutex. More...

	~CriticalSection ()
	Destructor. More...

Private Attributes
SystemMutex &	m_mutex
	The mutex. More...

Detailed Description

A class which provides a simple way to implement a Critical Section.

When more than one SystemThread needs to access a shared resource, we control access by acquiring a SystemMutex. The CriticalSection class uses the C++ scoping rules to automatically perform the required Lock and Unlock operations on the shared SystemMutex to implement a Critical Section.

If one wants to treat an entire method call as a critical section, one would do something like,

Class::Method ()
{
  CriticalSection cs (mutex);
  ...
}

In this case, the critical section is entered when the CriticalSection object is created, and the critical section is exited when the CriticalSection object goes out of scope at the end of the method.

Finer granularity is achieved by using local scope blocks.

Class::Method ()
{
  ...
  {
    CriticalSection cs (mutex);
  }
  ...
}

Here, the critical section is entered partway through the method when the CriticalSection object is created in the local scope block (the braces). The critical section is exited when the CriticalSection object goes out of scope at the end of block.