#include <e32base.h>
| class CBufFlat : public CBufBase |
| Public Member Functions | |
|---|---|
| ~CBufFlat() | |
| virtual IMPORT_C TPtr8 | BackPtr(TInt) |
| TInt | Capacity() |
| virtual IMPORT_C void | Compress() |
| virtual IMPORT_C void | Delete(TInt, TInt) |
| IMPORT_C CBufFlat * | NewL(TInt) |
| virtual IMPORT_C TPtr8 | Ptr(TInt) |
| IMPORT_C void | SetReserveL(TInt) |
| Protected Member Functions | |
|---|---|
| CBufFlat(TInt) | |
| Inherited Attributes | |
|---|---|
| CBufBase::iExpandSize | |
| CBufBase::iSize | |
Provides a flat storage dynamic buffer.
This class should be used when high-speed pointer lookup is an important consideration, and you are reasonably confident that the insertion of data will not fail.
This class is an implementation of the abstract buffer interface provided by CBufBase and uses a single heap cell to contain the data.
| IMPORT_C | ~CBufFlat | ( | ) |
Destructor.
Frees all resources owned by the object, prior to its destruction. Specifically, it frees the allocated cell used as a buffer.
Reimplemented from CBufBase::BackPtr(TInt)
Gets a pointer descriptor to represent the data starting at the beginning of the contiguous region containing that byte through to the byte immediately preceding the specified byte.
The descriptor always points to the beginning of the buffer containing the specified byte. Calculation of the pointer and length involves only a few machine instructions and is independent of the data contained in the buffer.
See also: CBufBase::BackPtr
| Parameter | Description |
|---|---|
| aPos | Buffer position: must be in range zero to Size(). |
Returns: Descriptor representing the back contiguous region.
| TInt | Capacity | ( | ) | const [inline] |
Gets the size to which the buffer may expand without re-allocation.
Returns: The size of the allocated cell associated with the buffer. This is the maximum size the buffer may be expanded to without re-allocation.
| IMPORT_C void | Compress | ( | ) | [virtual] |
Reimplemented from CBufBase::Compress()
Compresses the buffer so as to occupy minimal space.
This frees any unused memory at the end of the buffer.
See also: CBufBase::Compress
Reimplemented from CBufBase::Delete(TInt,TInt)
Deletes data from the buffer.
During deletion, any data beyond the deleted data is shuffled up so that the buffer contents are contiguous. No memory is freed.
See also: CBufBase::Delete
| Parameter | Description |
|---|---|
| aPos | Buffer position where the deletion will begin; must be in the range zero to (Size() minus the length of the data to be deleted). |
| aLength | The number of bytes to be deleted. |
Allocates and constructs a flat buffer.
If there is insufficient memory available to allocate the flat buffer, the function leaves.
| Parameter | Description |
|---|---|
| anExpandSize | The granularity of buffer expansion. Additional space, when required, is always allocated in multiples of this number. Note: although a value of zero is permitted by this interface, it has no meaning, and risks raising panics later during execution. We suggest that you pass a positive value. |
Returns: A pointer to the flat buffer object.
Reimplemented from CBufBase::Ptr(TInt)
Gets a pointer descriptor to represent the data starting at the specified data byte through to the end of the contiguous region containing that byte.
Calculation of the pointer and length involves only a few machine instructions and is independent of the data contained in the buffer.
| Parameter | Description |
|---|---|
| aPos | Buffer position: must be in range zero to Size(). |
Returns: Descriptor representing the data starting at aPos to the end of the buffer.
| IMPORT_C void | SetReserveL | ( | TInt | aSize | ) |
Specifies a minimum amount of space which the flat buffer should occupy.
If the required size is zero, the heap cell is deleted. If it is different from the current size, the heap cell is rellocated accordingly.
| Parameter | Description |
|---|---|
| aSize | The size of the buffer required. If there is no data in the buffer, i.e. Size() returns zero, then this value can be zero, which causes the buffer's allocated heap cell to be deleted. |