vpr::RWMutexNSPR Class Reference

Read/write mutex implementation using NSPR read/write mutexes (PRRWLock). More...

#include <vpr/Sync/RWMutex.h>

List of all members.

Public Member Functions
	RWMutexNSPR ()
	~RWMutexNSPR ()
vpr::ReturnStatus	acquire ()
	Locks the mutex.
vpr::ReturnStatus	acquireRead ()
	Acquires a read mutex.
vpr::ReturnStatus	acquireWrite ()
	Acquires a write mutex.
vpr::ReturnStatus	tryAcquire ()
	Tries to acquire the mutex.
vpr::ReturnStatus	tryAcquireRead ()
	Tries to acquire a read mutex.
vpr::ReturnStatus	tryAcquireWrite ()
	Tries to acquire a write mutex.
vpr::ReturnStatus	release ()
	Releases the mutex.
Protected Member Functions
void	operator= (const RWMutexNSPR &)
	RWMutexNSPR (const RWMutexNSPR &)
Protected Attributes
int	numWaitingReaders
	Tests the current lock status. Number of waiting readers.
int	numWaitingWriters
	Number of waiting writers.
int	mRefCount
	Value is -1 if writer has the lock, else this keeps track of the number of readers holding the lock.
PRRWLock *	mRwLock

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Detailed Description

Read/write mutex implementation using NSPR read/write mutexes (PRRWLock).

This is typedef'd to vpr::RWMutex.

Definition at line 61 of file RWMutexNSPR.h.

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Constructor & Destructor Documentation

vpr::RWMutexNSPR::RWMutexNSPR

(

)

[inline]

Definition at line 64 of file RWMutexNSPR.h.

                 : mRwLock(NULL)
   {
      // Note the second argument "VPR RW Mutex" is for debug purposes only
      mRwLock = PR_NewRWLock(0, "VPR RW Mutex");
   }

vpr::RWMutexNSPR::~RWMutexNSPR

(

)

[inline]

Definition at line 70 of file RWMutexNSPR.h.

   {
      PR_DestroyRWLock(mRwLock);
   }

vpr::RWMutexNSPR::RWMutexNSPR

(

const RWMutexNSPR &

)

[inline, protected]

Definition at line 172 of file RWMutexNSPR.h.

   {
      /* Do nothing. */ ;
   }

---

Member Function Documentation

vpr::ReturnStatus vpr::RWMutexNSPR::acquire

(

)

[inline]

Locks the mutex.

Returns:

vpr::ReturnStatus::Succeed is returned if the mutex is acquired.

vpr::ReturnStatus::Fail is returned upon error.

Definition at line 81 of file RWMutexNSPR.h.

   {
      return acquireWrite();
   }

vpr::ReturnStatus vpr::RWMutexNSPR::acquireRead

(

)

[inline]

Acquires a read mutex.

Definition at line 89 of file RWMutexNSPR.h.

   {
      PR_RWLock_Rlock(mRwLock);
      return vpr::ReturnStatus();
   }

vpr::ReturnStatus vpr::RWMutexNSPR::acquireWrite

(

)

[inline]

Acquires a write mutex.

Definition at line 98 of file RWMutexNSPR.h.

   {
      PR_RWLock_Wlock(mRwLock);
      return vpr::ReturnStatus();
   }

vpr::ReturnStatus vpr::RWMutexNSPR::tryAcquire

(

)

[inline]

Tries to acquire the mutex.

Wait until the semaphore value is greater than 0. Then decrement by 1 and return. P operation.

Returns:

vpr::ReturnStatus::Succeed is returned if the mutex is acquired.

vpr::ReturnStatus::Fail is returned if the mutex is not acquired.

Definition at line 114 of file RWMutexNSPR.h.

   {
      return tryAcquireWrite();
   }

vpr::ReturnStatus vpr::RWMutexNSPR::tryAcquireRead

(

)

Tries to acquire a read mutex.

Definition at line 50 of file RWMutexNSPR.cpp.

References vpr::ReturnStatus::Fail.

{
   vpr::ReturnStatus retVal(vpr::ReturnStatus::Fail);

/*
   if (stateLock.acquire().success())
   {
      if (mRefCount == -1 || numWaitingWriters >0)
      {
         retVal.setCode(vpr::ReturnStatus::Fail);
      }
      else
      {
         mRefCount++;
         retVal.setCode(vpr::ReturnStatus::Succeed);
      }
      stateLock.release();
   }
*/
   return retVal;
}

vpr::ReturnStatus vpr::RWMutexNSPR::tryAcquireWrite

(

)

Tries to acquire a write mutex.

Definition at line 72 of file RWMutexNSPR.cpp.

References vpr::ReturnStatus::Fail.

{
   vpr::ReturnStatus retVal(vpr::ReturnStatus::Fail);

/*
   if (stateLock.acquire().success())
   {
      if ( mRefCount == 0 )
      {
         mRefCount = -1;
         retVal.setCode(vpr::ReturnStatus::Succeed);
      }
      stateLock.release();
   }
*/

   return retVal;
}

vpr::ReturnStatus vpr::RWMutexNSPR::release

(

)

[inline]

Releases the mutex.

Returns:

vpr::ReturnStatus::Succeed is returned on success.

vpr::ReturnStatus::Fail is returned on error.

Definition at line 135 of file RWMutexNSPR.h.

   {
      PR_RWLock_Unlock(mRwLock);
      return vpr::ReturnStatus();
   }

void vpr::RWMutexNSPR::operator=

(

const RWMutexNSPR &

)

[inline, protected]

Definition at line 167 of file RWMutexNSPR.h.

   {
      /* Do nothing. */ ;
   }

---

Member Data Documentation

int vpr::RWMutexNSPR::numWaitingReaders [protected]

Tests the current lock status. Number of waiting readers.

Returns:

0 is returned if this mutex is not locked.

1 is returned if this mutex is locked.

Definition at line 155 of file RWMutexNSPR.h.

int vpr::RWMutexNSPR::numWaitingWriters [protected]

Number of waiting writers.

Definition at line 156 of file RWMutexNSPR.h.

int vpr::RWMutexNSPR::mRefCount [protected]

Value is -1 if writer has the lock, else this keeps track of the number of readers holding the lock.

Definition at line 162 of file RWMutexNSPR.h.

PRRWLock* vpr::RWMutexNSPR::mRwLock [protected]

Definition at line 164 of file RWMutexNSPR.h.

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The documentation for this class was generated from the following files:

• RWMutexNSPR.h
• RWMutexNSPR.cpp

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