Class CCirBufBase

class CCirBufBase : public CBase;

Description

Base class for circular buffers.

The class is part of the implementation of circular buffers and is never instantiated.

The class provides member functions that form part of the interface.

Derivation

• CBase - Base class for all classes to be instantiated on the heap.

• CCirBufBase - Base class for circular buffers.

Members

Defined in CCirBufBase:

• CCirBufBase(TInt)Constructor taking the size of an object within the buffer.
• Count()constGets the current number of objects in this circular buffer.
• DoAdd(const TUint8 *)Implementation function for CCirBuf::Add(const T *)
• DoAdd(const TUint8 *,TInt)Implementation function for CCirBuf::Add(const T *,TInt)
• DoRemove(TUint8 *)Implementation function for CCirBuf::Remove(T *)
• DoRemove(TUint8 *,TInt)Implementation function for CCirBuf::Remove(T *,TInt)
• Length()constGets the maximum capacity of this circular buffer.
• Reset()Empties the buffer.
• SetLengthL(TInt)Sets the maximum capacity of this circular buffer, and resets all of the buffer ...
• iCount
• iHead
• iLength
• iPtr
• iPtrE
• iSize
• iTail
• ~CCirBufBase()Destructor.

Inherited from CBase:

• Delete(CBase *)Deletes the specified object.
• Extension_(TUint,TAny *&,TAny *)Extension function
• operator new(TUint)Allocates the object from the heap and then initialises its contents to binary z...
• operator new(TUint,TAny *)Initialises the object to binary zeroes.
• operator new(TUint,TLeave)Allocates the object from the heap and then initialises its contents to binary z...
• operator new(TUint,TLeave,TUint)Allocates the object from the heap and then initialises its contents to binary z...
• operator new(TUint,TUint)Allocates the object from the heap and then initialises its contents to binary z...

IMPORT_C ~CCirBufBase();

Description

Destructor.

This frees the memory allocated to the buffer.

protected: IMPORT_C CCirBufBase(TInt aSize);

Description

Constructor taking the size of an object within the buffer.

Parameters

Panic codes

inline TInt Count() const;

Description

Gets the current number of objects in this circular buffer.

Return value

inline TInt Length() const;

Description

Gets the maximum capacity of this circular buffer.

The capacity is the maximum number of elements that the buffer can hold.

Use CCirBufBase::SetLengthL(TInt) to change the capacity of the circular buffer.

Return value

See also:

• CCirBufBase::SetLengthL(TInt)Sets the maximum capacity of this circular buffer, and resets all of the buffer ...

IMPORT_C void SetLengthL(TInt aLength);

Description

Sets the maximum capacity of this circular buffer, and resets all of the buffer pointers.

The capacity is the maximum number of elements that the buffer can hold.

The buffer itself is allocated as a result of a call to this function. If the function has previously been called, then any existing buffer is freed and any information in it is lost.

Notes:

1. This function must be called before attempting to add any objects to the buffer.

2. The function can leave if there is insufficient memory available to allocate the buffer.

Parameters

Panic codes

IMPORT_C void Reset();

Description

Empties the buffer.

protected: IMPORT_C TInt DoAdd(const TUint8 *aPtr);

Description

Implementation function for CCirBuf::Add(const T *)

Adds a single object to the circular buffer, but only if there is space available.

Parameters

Return value

Panic codes

See also:

• CCirBuf::Add(const T *)Adds a single object to the circular buffer.
• CCirBufBase::SetLengthL(TInt)Sets the maximum capacity of this circular buffer, and resets all of the buffer ...

protected: IMPORT_C TInt DoAdd(const TUint8 *aPtr, TInt aCount);

Description

Implementation function for CCirBuf::Add(const T *,TInt)

Adds multiple objects to the circular buffer, but only if there is space available.

Parameters

Return value

Panic codes

See also:

• CCirBuf::Add(const T *)Adds a single object to the circular buffer.
• CCirBufBase::SetLengthL(TInt)Sets the maximum capacity of this circular buffer, and resets all of the buffer ...

protected: IMPORT_C TInt DoRemove(TUint8 *aPtr);

Description

Implementation function for CCirBuf::Remove(T *)

Removes a single object from the circular buffer, but only if there are objects in the buffer.

A binary copy of the object is made to aPtr.

Parameters

Return value

See also:

• CCirBuf::Remove(T *)Removes a single object from the circular buffer.

protected: IMPORT_C TInt DoRemove(TUint8 *aPtr, TInt aCount);

Description

Implementation function for CCirBuf::Remove(T *,TInt)

Attempts to remove aCount objects from the circular buffer, but only if there are objects in the buffer.

A binary copy of the objects is made to aPtr.

Parameters

Return value

Panic codes

See also:

• CCirBuf::Remove(T *)Removes a single object from the circular buffer.

protected: TInt iCount;

Description

protected: TInt iSize;

Description

protected: TInt iLength;

Description

protected: TUint8 * iPtr;

Description

protected: TUint8 * iPtrE;

Description

protected: TUint8 * iHead;

Description

protected: TUint8 * iTail;

Description