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SYMBIAN OS V9.3

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Location: e32base.h

Class CCirBuf

class CCirBuf : public CCirBufBase;

Description

A circular buffer containing objects of a type defined by the template parameter.

Derivation

Members

Defined in CCirBuf:
Add(), Add(), CCirBuf(), Remove(), Remove()

Inherited from CBase:
Delete(), Extension_(), operator new()

Inherited from CCirBufBase:
Count(), DoAdd(), DoRemove(), Length(), Reset(), SetLengthL(), iCount, iHead, iLength, iPtr, iPtrE, iSize, iTail


Construction and destruction


CCirBuf()

inline CCirBuf();

Description

Default C++ constructor.

The size of each object in the buffer is fixed and is the length of the class passed as the template parameter.

Panic codes

E32USER-CBase

72, if the length of the template class is zero.

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Member functions


Add()

inline TInt Add(const T *aPtr);

Description

Adds a single object to the circular buffer.

The object is of type class T and is only added if there is space available.

Parameters

const T *aPtr

A pointer to the object of type class T to be added to the circular buffer.

Return value

TInt

1 if the object is successfully added. 0 if the object cannot be added because the circular buffer is full.

Panic codes

E32USER-CBase

74, if a call to CCirBufBase::SetLengthL() has not been made before calling this function.


Add()

inline TInt Add(const T *aPtr, TInt aCount);

Description

Adds multiple objects to the circular buffer.

The function attempts to add aCount objects of type class T. The objects are only added if there is space available.

Parameters

const T *aPtr

A pointer to a set of contiguous objects of type class T to be added to the circular buffer.

TInt aCount

The number of objects to be added to the circular buffer.

Return value

TInt

The number of objects successfully added to the buffer. This value may be less than the number requested and can range from 0 to aCount.

Panic codes

E32USER-CBase

74, if a call to CCirBufBase::SetLengthL() has not been made before calling this function.

E32USER-CBase

75, if aCount is not a positive value.


Remove()

inline TInt Remove(T *aPtr);

Description

Removes a single object from the circular buffer.

An object can only be removed if there are objects in the buffer.

A binary copy of the object is made to aPtr.

Parameters

T *aPtr

A pointer to an object of type class T supplied by the caller.

Return value

TInt

1 if an object is successfully removed. 0 if an object cannot be removed because the circular buffer is empty.


Remove()

inline TInt Remove(T *aPtr, TInt aCount);

Description

Removes multiple objects from the circular buffer.

The function attempts to remove aCount objects of type class T. Objects can only be removed if there are objects in the buffer

A binary copy of the objects is made to aPtr.

Parameters

T *aPtr

A pointer to contiguous memory able to hold aCount class T objects, supplied by the caller.

TInt aCount

The number of objects to be removed from the circular buffer.

Return value

TInt

The number of objects successfully removed from the buffer. This value may be less than the number requested, and can range from 0 to aCount.

Panic codes

E32USER-CBase

76, if aCount is not a positive value.