Defines, Structures, Typedefs, Functions. More...

Files
file	clBufferApi.h
	Header file of Buffer Management related APIs.

Classes
struct	ClBufferPoolConfigT
	The type of the buffer configuration info. More...

Typedefs
typedef ClPtrT	ClBufferHandleT
	The type of the handle for the buffer messages.
typedef enum ClBufferMode	ClBufferModeT
	The config mode of the Buffer.

Enumerations
enum	ClBufferMode { CL_BUFFER_NATIVE_MODE, CL_BUFFER_PREALLOCATED_MODE }
	The config mode of the Buffer. More...
enum	ClBufferSeekTypeT { CL_BUFFER_SEEK_SET = 0, CL_BUFFER_SEEK_CUR, CL_BUFFER_SEEK_END }

Functions
ClRcT	clBufferChecksum16Compute (ClBufferHandleT messageHandle, ClUint32T startOffset, ClUint32T length, ClUint16T *pChecksum)
	Computes a 16-bit checksum on a message.
ClRcT	clBufferChecksum32Compute (ClBufferHandleT messageHandle, ClUint32T startOffset, ClUint32T length, ClUint32T *pChecksum)
	Computes a 32-bit checksum on a message.
ClRcT	clBufferClear (ClBufferHandleT messageHandle)
	Deletes the content of the buffer message.
ClRcT	clBufferConcatenate (ClBufferHandleT destination, ClBufferHandleT *pSource)
	Concatenates source message to destination message.
ClRcT	clBufferCreate (ClBufferHandleT *pMessageHandle)
	Creates a new message.
ClRcT	clBufferCreateAndAllocate (ClUint32T size, ClBufferHandleT *pMessageHandle)
	Creates buffers for a requested size of a message.
ClRcT	clBufferDataPrepend (ClBufferHandleT messageHandle, ClUint8T *pByteBuffer, ClUint32T numberOfBytesToWrite)
	Prepends specified number of bytes at the begining of message.
ClRcT	clBufferDelete (ClBufferHandleT *pMessageHandle)
	Deletes the Buffers.
ClRcT	clBufferDuplicate (ClBufferHandleT messageHandle, ClBufferHandleT *pDuplicatedMessage)
	Duplicates a message.
ClRcT	clBufferFinalize (void)
	Cleans up the Buffer Management library.
ClRcT	clBufferFlatten (ClBufferHandleT messageHandle, ClUint8T **ppFlattenBuffer)
	Flattens message into a single buffer.
ClRcT	clBufferHeaderTrim (ClBufferHandleT messageHandle, ClUint32T numberOfBytes)
	Trims the start of the message.
ClRcT	clBufferInitialize (const ClBufferPoolConfigT *pConfig)
	Initializes the Buffer Management library.
ClRcT	clBufferKernelToUserCopy (ClBufferHandleT kernelMessageHandle, ClBufferHandleT userMessageHandle)
	Copies message from kernel-space to user-space.
ClRcT	clBufferLengthCalc (ClBufferHandleT bufferHandle)
	Recompute the message length & set internal variable.
ClRcT	clBufferLengthGet (ClBufferHandleT messageHandle, ClUint32T *pMessageLength)
	Returns the length of the message.
ClRcT	clBufferNBytesRead (ClBufferHandleT messageHandle, ClUint8T pByteBuffer, ClUint32T pNumberOfBytesToRead)
	Reads the specified number of bytes of data from a message.
ClRcT	clBufferNBytesWrite (ClBufferHandleT messageHandle, ClUint8T *pByteBuffer, ClUint32T numberOfBytesToWrite)
	Writes the specified number bytes of data from a message.
ClRcT	clBufferReadOffsetGet (ClBufferHandleT messageHandle, ClUint32T *pReadOffset)
	Returns current read offset of the message.
ClRcT	clBufferReadOffsetSet (ClBufferHandleT messageHandle, ClInt32T newReadOffset, ClBufferSeekTypeT seekType)
	Sets current read offset of the message.
ClRcT	clBufferShrink (ClPoolShrinkOptionsT *pShrinkOptions)
	Frees up the unused pools of all sizes.
ClRcT	clBufferToBufferCopy (ClBufferHandleT sourceMessage, ClUint32T sourceMessageOffset, ClBufferHandleT destinationMessage, ClUint32T numberOfBytes)
	Copies specific number of bytes from one message to another.
ClRcT	clBufferTrailerTrim (ClBufferHandleT messageHandle, ClUint32T numberOfBytes)
	Trims the tail of the message.
ClRcT	clBufferUserToKernelCopy (ClBufferHandleT userMessageHandle, ClBufferHandleT *pKernelMessageHandle)
	Copies message from user-space to kernel-space.
ClRcT	clBufferWriteOffsetGet (ClBufferHandleT messageHandle, ClUint32T *pWriteOffset)
	Returns current write offset of the message.
ClRcT	clBufferWriteOffsetSet (ClBufferHandleT messageHandle, ClInt32T newWriteOffset, ClBufferSeekTypeT seekType)
	Sets current write offset of the message.
ClRcT	clDbgBufferPrint (ClBufferHandleT buffer)
	Dumps the buffer for debugging, etc.

Detailed Description

Defines, Structures, Typedefs, Functions.

Typedef Documentation

typedef enum ClBufferMode ClBufferModeT

The config mode of the Buffer.

When configured in native mode, malloc is used for fetching the memory for the configured buffer pools instead of the clovis pool implementation.

Enumeration Type Documentation

enum ClBufferMode

The config mode of the Buffer.

When configured in native mode, malloc is used for fetching the memory for the configured buffer pools instead of the clovis pool implementation.

Enumerator:

CL_BUFFER_NATIVE_MODE	In this mode the buffer library uses the malloc and free for allocating and deallocating memory for buffers.
CL_BUFFER_PREALLOCATED_MODE	This mode makes buffer library uses Clovis implementation of Pool for allocating and deallocating memory for buffers.

enum ClBufferSeekTypeT

Enumerator:

CL_BUFFER_SEEK_SET	This is to set the read or write offset pointer to a position mentioned from the BEGINING of the Buffer message.
CL_BUFFER_SEEK_CUR	This is to set the read or write offset pointer to a position mentioned from the CURRENT position of the pointer of the Buffer message.
CL_BUFFER_SEEK_END	This is to set the read or write offset pointer to a position mentioned from the END of the Buffer message.

Function Documentation

ClRcT clBufferChecksum16Compute	(	ClBufferHandleT	messageHandle,
		ClUint32T	startOffset,
		ClUint32T	length,
		ClUint16T *	pChecksum
	)

Computes a 16-bit checksum on a message.

Header File:: clBufferApi.h

Parameters

messageHandle	Handle to the message returned by clBufferCreate() API for which the checksum is to be computed.
startOffset	Offset from the beginning of the message, from which the data for computing the checksum begins.
length	Number of bytes of data for which the checksum is to be computed.
pChecksum	(out) Pointer to variable of type ClUint32T in which the computed checksum is returned.

Return values

CL_OK	The API executed successfully.
CL_ERR_NULL_POINTER	On passing a NULL pointer.
CL_ERR_INVALID_HANDLE	On passing an invalid handle.
CL_ERR_NOT_INITIALIZED	If Buffer Management library is not initialized.

Description:: This API is used to compute a 16-bit checksum on a message from startOffset for length number of bytes in the message. This checksum can be used to check the validity of the buffer message after passing it through a network.

Library Files:: ClBuffer

See Also: clBufferCreate(), clBufferChecksum32Compute()

ClRcT clBufferChecksum32Compute	(	ClBufferHandleT	messageHandle,
		ClUint32T	startOffset,
		ClUint32T	length,
		ClUint32T *	pChecksum
	)

Computes a 32-bit checksum on a message.

Header File:: clBufferApi.h

Parameters

messageHandle	Handle to the message returned by clBufferCreate() API for which the checksum is to be computed.
startOffset	Offset from the beginning of the message, from which the data for computing the checksum begins.
length	Number of bytes of data for which the checksum is to be computed.
pChecksum	(out) Pointer to variable of type ClUint32T in which the computed checksum is returned.

Return values

CL_OK	The API executed successfully.
CL_ERR_NULL_POINTER	On passing a NULL pointer.
CL_ERR_INVALID_HANDLE	On passing an invalid handle.
CL_ERR_NOT_INITIALIZED	If Buffer Management library is not initialized.

Description:: This API is used to compute a 32-bit checksum on a message from startOffset for length number of bytes in the message. This checksum can be used to check the validity of the buffer message after passing it through a network.

Library Files:: ClBuffer

See Also: clBufferCreate(), clBufferChecksum16Compute()

ClRcT clBufferClear ( ClBufferHandleT messageHandle )

Deletes the content of the buffer message.

Header File:: clBufferApi.h

Parameters

pMessageHandle Pointer to the message handle returned by clBufferCreate() API.

Return values

CL_OK	The buffer message is cleared successfully.
CL_ERR_NULL_POINTER	On passing a NULL pointer.
CL_ERR_INVALID_HANDLE	On passing an invalid handle.
CL_ERR_NOT_INITIALIZED	If Buffer Management library is not initialized.

Description:: This API is used to delete message buffer(s) designated by the handle obtained through clBufferCreate() API. The handle is still available for re-use.

Library Files:: ClBuffer

See Also: clBufferDelete(), clBufferCreateAndAllocate(), clBufferCreate()

ClRcT clBufferConcatenate	(	ClBufferHandleT	destination,
		ClBufferHandleT *	pSource
	)

Concatenates source message to destination message.

Header File:: clBufferApi.h

Parameters

destination	This is buffer message handle to which the pSource buffer message will be concatinated. The handle of the concatenated message will be the same destination buffer message handle .
pSource	(in/out) Pointer to buffer message handle of the message, which is to be concatenated with destination buffer message.

Return values

CL_OK	The API executed successfully.
CL_ERR_NULL_POINTER	On passing a NULL pointer.
CL_ERR_INVALID_HANDLE	On passing an invalid handle.
CL_ERR_NOT_INITIALIZED	If Buffer Management library is not initialized.

Description:: This API is used to concatenate the pSource buffer message to the end of destination message. The pSource message handle will become not-usable after this concatination operation and the pSource message will be deleted. The write offset of the resultant destination message will be set to end of the message and the read offset of the to start of the message.

Library Files:: ClBuffer

See Also: clBufferCreate(), clBufferDataAppend(), clBufferDelete(), clBufferDataPrepend()

ClRcT clBufferCreate ( ClBufferHandleT * pMessageHandle )

Creates a new message.

Header File:: clBufferApi.h

Parameters

pMessageHandle (out) A pointer to the handle of type ClBufferHandleT designating the buffer for a message created.

Return values

CL_OK	The API successfully created a buffer for a message.
CL_ERR_NULL_POINTER	On passing a NULL pointer.
CL_ERR_NO_MEMORY	On memory allocation failure.
CL_ERR_NOT_INITIALIZED	If Buffer Management library is not initialized.

Description:: This API is used to create a buffer for a message. It allocates a buffer of 2 kilobytes size, even if a write operation on the buffer is to be performed at a later stage in the application. The write operation on the buffer handle provided by this API, the buffer management library will use this pre-allocated buffer.

Library Files:: ClBuffer

See Also: clBufferCreateAndAllocate(), clBufferDelete(), clBufferClear()

ClRcT clBufferCreateAndAllocate	(	ClUint32T	size,
		ClBufferHandleT *	pMessageHandle
	)

Creates buffers for a requested size of a message.

Header File:: clBufferApi.h

Parameters

size	Initial size of a message buffer in bytes.
pMessageHandle	A pointer to the buffer message of type ClBufferHandleT designating the message buffer created.

Return values

CL_OK	The buffers for a message are successfully created.
CL_ERR_NULL_POINTER	On passing a NULL pointer.
CL_ERR_NO_MEMORY	On memory allocation failure.
CL_ERR_NOT_INITIALIZED	If Buffer Management library is not initialized.

Description:: This API is used to create buffers to hold a message of size mentioned by size. It allocates the buffers even if the write operation is to be performed at a later stage in application. As a write is performed onto this buffer handle returned by this API, the buffer management library will use these pre-allocated buffers.

Library Files:: ClBuffer

See Also: clBufferDelete(), clBufferClear(), clBufferCreate()

ClRcT clBufferDataPrepend	(	ClBufferHandleT	messageHandle,
		ClUint8T *	pByteBuffer,
		ClUint32T	numberOfBytesToWrite
	)

Prepends specified number of bytes at the begining of message.

Header File:: clBufferApi.h

Parameters

messageHandle	Handle to the message returned by clBufferCreate() API.
pByteBuffer	Pointer to a variable of type ClUint8T, in which numberOfBytesToRead bytes of data is returned.
numberOfBytesToWrite	Number of bytes to be written.

Return values

CL_OK	The API executed successfully.
CL_ERR_NULL_POINTER	On passing a NULL pointer.
CL_ERR_INVALID_HANDLE	On passing an invalid handle.
CL_ERR_NOT_INITIALIZED	If Buffer Management library is not initialized.

Description:: This API is used to prepend numberOfBytesToWrite number of bytes at the beginning of the buffer message. The write offset of the buffer message will be updated and is set to numberOfBytesToWrite, i.e. the next write-operation performed will begin the write at numberOfBytesToWrite offset from the starting of the message. Note that the current write offset is lost. Hence, it is advisable to preserve the write offset before invoking this API.

Library Files:: ClBuffer

See Also: clBufferNBytesWrite(), clBufferConcatenate(), clBufferDelete()

ClRcT clBufferDelete ( ClBufferHandleT * pMessageHandle )

Deletes the Buffers.

Header File:: clBufferApi.h

Parameters

pMessageHandle Pointer to the message handle, which is to be deleted.

Return values

CL_OK	The Buffers are deleted successfully.
CL_ERR_NULL_POINTER	On passing a NULL pointer.
CL_ERR_INVALID_HANDLE	On passing an invalid handle.
CL_ERR_NOT_INITIALIZED	If Buffer Management library is not initialized.

Description:: This API is used to delete message buffer(s) designated by the handle obtained through clBufferCreate() API. Successful invocation of this API will make the handle invalid.

Library Files:: ClBuffer

See Also: clBufferClear(), clBufferCreateAndAllocate(), clBufferCreate()

ClRcT clBufferDuplicate	(	ClBufferHandleT	messageHandle,
		ClBufferHandleT *	pDuplicatedMessage
	)

Duplicates a message.

Header File:: clBufferApi.h

Parameters

messageHandle	Handle to the message returned by clBufferCreate() API, which is to be duplicated.
pDuplicatedMessage	(out) Pointer to variable of type ClBufferHandleT, in which handle of the duplicate message is returned.

Return values

CL_OK	The API executed successfully.
CL_ERR_NULL_POINTER	On passing a NULL pointer.
CL_ERR_INVALID_HANDLE	On passing an invalid handle.
CL_ERR_NOT_INITIALIZED	If Buffer Management library is not initialized.
CL_ERR_INVALID_PARAMETER	On passing an invalid parameter.
CL_ERR_NO_MEMORY	On memory allocation failure.

Description:: This API is used to make duplicate copy of messageHandle. The newly created buffer message handle will be returned in pDuplicateMessage. The read and write offsets of the newly created buffer message are set to the values same as that of the messageHandle.

Library Files:: ClBuffer

See Also: clBufferCreate(), clBufferDelete(), clBufferToBufferCopy()

ClRcT clBufferFinalize ( void )

Cleans up the Buffer Management library.

Header File:: clBufferApi.h

Parameters:: None

Return values

CL_OK	The API executed successfully.
CL_ERR_NOT_INITIALIZED	If Buffer Management library is not initialized.

Description:: This API is should be called when an application decides of not using the buffer management library any more. The application must have invoked clBufferInitialize() before it invokes this function. It is called typically when an application calling this function is shutting down and wants to releave all the resources used by it.

Library Files:: ClBuffer

See Also: clBufferInitialize()

ClRcT clBufferFlatten	(	ClBufferHandleT	messageHandle,
		ClUint8T **	ppFlattenBuffer
	)

Flattens message into a single buffer.

Header File:: clBufferApi.h

Parameters

messageHandle	Handle to message returned by clBufferCreate() API.
ppFlattenBuffer	(out) The flatten buffer would be returned in this location. This must be a valid pointer and cannot be NULL.

Return values

CL_OK	The API executed successfully.
CL_ERR_NULL_POINTER	On passing a NULL pointer.
CL_ERR_INVALID_HANDLE	On passing an invalid handle.
CL_ERR_NOT_INITIALIZED	If Buffer Management library is not initialized.
CL_ERR_NO_MEMORY	On memory allocation failure.

Description:: This API is used to copy the message from a buffer message into a single flat buffer stream. The buffer library will allocate the memory for the flat buffer stream and this has to be freed by the caller of this API.

Library Files:: ClBuffer

See Also: clBufferCreate(), clBufferDelete()

ClRcT clBufferHeaderTrim	(	ClBufferHandleT	messageHandle,
		ClUint32T	numberOfBytes
	)

Trims the start of the message.

Header File:: clBufferApi.h

Parameters

messageHandle	Handle to the message returned by clBufferCreate() API.
numberOfBytes	Number of bytes to delete from the start of the message.

Return values

CL_OK	The API executed successfully.
CL_ERR_NULL_POINTER	On passing a NULL pointer.
CL_ERR_INVALID_HANDLE	On passing an invalid handle.
CL_ERR_NOT_INITIALIZED	If Buffer Management library is not initialized.
CL_ERR_INVALID_PARAMETER	On passing an invalid parameter.

Description:: This API is used to delete a specific number of bytes from the start of the message pointed by messageHandle. If the read/write offset is in the region being deleted, the read/write offset will be set to 0, i.e, the beginning of the message, after performing the trim operation.

Library Files:: ClBuffer

See Also: clBufferCreate(), clBufferHeaderTrim(), clBufferDelete()

ClRcT clBufferInitialize ( const ClBufferPoolConfigT * pConfig )

Initializes the Buffer Management library.

Header File:: clBufferApi.h

Parameters:

Parameters

pConfig This should contain the pool configuration to be used by the Buffer library. If NULL is passed then the default pool configuration will be used.

Return values

CL_OK	The API executed successfully.
CL_ERR_NO_MEMORY	On memory allocation failure.
CL_ERR_INITIALIZED	If the Buffer Management library is already initialized.

Description:: This API is used to initialize the Buffer Management library. It must be called before calling any other Buffer library APIs. Since Buffer library uses OpenClovis OSAL APIs, the OSAL library should be initialized before intializing the Buffer library.

Library Files:: ClBuffer

See Also: clBufferFinalize()

ClRcT clBufferKernelToUserCopy	(	ClBufferHandleT	kernelMessageHandle,
		ClBufferHandleT	userMessageHandle
	)

Copies message from kernel-space to user-space.

Header File:: clBufferApi.h

Note: This API is available only inside the kernel. It cannot be invoked from the user-space.

Parameters

kernelMessageHandle	Handle to kernel-space message returned by clBufferCreate() API, from which data is to be copied into user-space message.
userMessageHandle	Handle to user-space message returned by clBufferCreate() API,into which data is to be copied from kernel-space message.

Return values

CL_OK	The API executed successfully.
CL_ERR_NULL_POINTER	On passing a NULL pointer.
CL_ERR_INVALID_HANDLE	On passing an invalid handle.
CL_ERR_NOT_INITIALIZED	If Buffer Management library is not initialized.
CL_ERR_NO_MEMORY	On memory allocation failure.

Description:: This API is used to copy a message from kernel-space to user-space. The user-space message must be created in user space. The contents of the kernel-space message will be copied into the user-space message.Write offset would be set to the end and read offset would point to the beginning of the user-space message.

Library Files:: ClBuffer

See Also: clBufferCreate(), clBufferDelete(), clBufferUserToKernelCopy()

ClRcT clBufferLengthCalc ( ClBufferHandleT bufferHandle )

Recompute the message length & set internal variable.

Parameters

messageHandle Handle to the message returned by clBufferCreate() API.

Return values

CL_OK	The API executed successfully.
CL_ERR_NULL_POINTER	On passing a NULL pointer.
CL_ERR_INVALID_HANDLE	On passing an invalid handle.
CL_ERR_NOT_INITIALIZED	If Buffer Management library is not initialized.

Description:: This API is used to recompute the total message length, to be used if another entity (IOC) fools with the buffers.

Library Files:: ClBuffer

ClRcT clBufferLengthGet	(	ClBufferHandleT	messageHandle,
		ClUint32T *	pMessageLength
	)

Returns the length of the message.

Header File:: clBufferApi.h

Parameters

messageHandle	Handle to the message returned by clBufferCreate() API.
pMessageLength	(out) Pointer to a variable of type ClUint32T, in which the total length of the message is returned.

Return values

CL_OK	The API executed successfully.
CL_ERR_NULL_POINTER	On passing a NULL pointer.
CL_ERR_INVALID_HANDLE	On passing an invalid handle.
CL_ERR_NOT_INITIALIZED	If Buffer Management library is not initialized.

Description:: This API is used to retrieve the total length of the message. There is no impact on the read and write offset of the message even on subsequent invocation of this API.

Library Files:: ClBuffer

See Also: clBufferCreate(), clBufferNBytesWrite()

ClRcT clBufferNBytesRead	(	ClBufferHandleT	messageHandle,
		ClUint8T *	pByteBuffer,
		ClUint32T *	pNumberOfBytesToRead
	)

Reads the specified number of bytes of data from a message.

Header File:: clBufferApi.h

Parameters

messageHandle	Handle to the message returned by clBufferCreate() API.
pByteBuffer	Pointer to a stream of memory of type ClUint8T, in which pNumberOfBytesToRead of the read data is returned. Memory allocation and deallocation for this parameter must be done by the caller.
pNumberOfBytesToRead	Pointer to variable of type ClUint32T, which contains number of bytes of data to be read. And the number of bytes of data that has been successfully read is returned in this parameter.

Return values

CL_OK	The API executed successfully.
CL_ERR_NULL_POINTER	On passing a NULL pointer.
CL_ERR_INVALID_HANDLE	On passing an invalid handle.
CL_ERR_NOT_INITIALIZED	If Buffer Management library is not initialized.

Description:: This API is used to read *pNumberOfBytesToRead number of bytes of data from a buffer message pointed by messageHandle, starting from the where the last read has stopped at in that buffer message. If the buffer doesnt contain *pNumberOfBytesToRead number of bytes of data then *pNumberOfBytesToRead parameter will be updated with actually read number of bytes. The current read offset(or pointer), is automatically updated by *pNumberOfBytesToRead bytes after every read, so that the next read operation starts from the point where this read has left at.

Library Files:: ClBuffer

See Also: clBufferClear(), clBufferNBytesWrite(), clBufferCreate()

ClRcT clBufferNBytesWrite	(	ClBufferHandleT	messageHandle,
		ClUint8T *	pByteBuffer,
		ClUint32T	numberOfBytesToWrite
	)

Writes the specified number bytes of data from a message.

Header File:: clBufferApi.h

Parameters

messageHandle	Handle to the message returned by clBufferCreate() API into which n bytes of data is to be written.
pByteBuffer	Pointer to the byte buffer from which numberOfBytesToWrite bytes are to be written into the buffer message.
numberOfBytesToWrite	Number of bytes to be written.

Return values

CL_OK	The API executed successfully.
CL_ERR_NULL_POINTER	On passing a NULL pointer.
CL_ERR_INVALID_HANDLE	On passing an invalid handle.
CL_ERR_NOT_INITIALIZED	If Buffer Management library is not initialized.

Description:: This API is used to write n bytes of data into the message referred by the message handle, starting from the current write offset. While writing data to a buffer message if the buffer gets full then a new buffer will be allocated automatically and then the write continues into that buffer. The write offset is automatically updated by numberOfBytesToWrite bytes after every write, so that the next write can continue from the point where this write ended at.

Library Files:: ClBuffer

See Also: clBufferClear(), clBufferNBytesRead(), clBufferCreate()

ClRcT clBufferReadOffsetGet	(	ClBufferHandleT	messageHandle,
		ClUint32T *	pReadOffset
	)

Returns current read offset of the message.

Header File:: clBufferApi.h

Parameters

messageHandle	Handle to the message returned by clBufferCreate() API.
pReadOffset	Pointer to a variable of type ClUint32T, in which the current read offset is returned.

Return values

CL_OK	The API executed successfully.
CL_ERR_NULL_POINTER	On passing a NULL pointer.
CL_ERR_INVALID_HANDLE	On passing an invalid handle.
CL_ERR_NOT_INITIALIZED	If Buffer Management library is not initialized.

Description:: This API is used to retrieve the current read offset of the buffer message. This offset is updated on invoking the clBufferNBytesRead() API or it can be set using clBufferReadOffsetSet().

Library Files:: ClBuffer

See Also: clBufferCreate(), clBufferWriteOffsetGet() clBufferDelete(), clBufferReadOffsetSet() clBufferWriteOffsetSet(), clBufferTrailerTrim() clBufferHeaderTrim(), clBufferNBytesRead()

ClRcT clBufferReadOffsetSet	(	ClBufferHandleT	messageHandle,
		ClInt32T	newReadOffset,
		ClBufferSeekTypeT	seekType
	)

Sets current read offset of the message.

Header File:: clBufferApi.h

Parameters

messageHandle	Handle to the message returned by clBufferCreate() API
seekType	This parameter accepts the following values: `CL_BUFFER_SEEK_SET:` The read offset should be set to a position from the beginning of the message. `CL_BUFFER_SEEK_CUR:` The read offset should be set to a position from its current location. `CL_BUFFER_SEEK_END:` The read offset should be set to a position from the the end of the message.
newReadOffset	The offset at which the current read offset is to be set. If seekType is set to CL_BUFFER_SEEK_SET then the value of newReadOffset should be 0 or greater, for CL_BUFFER_SEEK_CUR it can be a positive of negative number and for CL_BUFFER_END it should be 0 or a negative number.

Return values

CL_OK	The API executed successfully.
CL_ERR_NULL_POINTER	On passing a NULL pointer.
CL_ERR_INVALID_HANDLE	On passing an invalid handle.
CL_ERR_NOT_INITIALIZED	If Buffer Management library is not initialized.
CL_ERR_INVALID_PARAMETER	On passing an invalid parameter.

Description:: This API is used to set the read offset of the buffer message pointed by the messageHandle. This is used, when an application wants to read the data from the buffer message from a specific point onwards. This offset is also automatically updated on invoking the clBufferNBytesRead().

Library Files:: ClBuffer

See Also: clBufferCreate(), clBufferWriteOffsetGet(), clBufferDelete(), clBufferWriteOffsetSet(), clBufferTrailerTrim(), clBufferHeaderTrim(), clBufferNBytesRead()

ClRcT clBufferShrink ( ClPoolShrinkOptionsT * pShrinkOptions )

Frees up the unused pools of all sizes.

Header File:: clBufferApi.h

Parameters

pShrinkOptions

This is pointer to the shrik option parameter of type ClPoolShrinkOptionsT. The values that can be passed are

CL_POOL_SHRINK_DEFAULT: This option will free half of total unused pools.
CL_POOL_SHRINK_ONE: This option will free only one pool of all the unused pools.
CL_POOL_SHRINK_ALL: This option will free all the unused pools.

Return values

CL_OK	The API executed successfully.
CL_ERR_NOT_INITIALIZED	If Buffer Management library is not initialized.

Description:: This API is used to free the unused pools. The new pools of a size get allocated when there is shortage of space for creating new buffer messages. And after using the buffer messages they will be freed using clBufferDelete(), but the pool remains. So these pools are required to be freed up at times.

Library Files:: ClBuffer

See Also: clBufferCreate(), clBufferDelete()

ClRcT clBufferToBufferCopy	(	ClBufferHandleT	sourceMessage,
		ClUint32T	sourceMessageOffset,
		ClBufferHandleT	destinationMessage,
		ClUint32T	numberOfBytes
	)

Copies specific number of bytes from one message to another.

Header File:: clBufferApi.h

Parameters

sourceMessage	Handle to the message returned by clBufferCreate() API, from which data is to be copied.
sourceMessageOffset	Offset with respect to beginning of sourceMessage, from where the copying is to begin.
destinationMessage	Handle to the message returned by clBufferCreate() API, into which data is being copied.
numberOfBytes	Number of bytes to be copied from sourceMessage to destinationMessage.

Return values

CL_OK	The API executed successfully.
CL_ERR_NULL_POINTER	On passing a NULL pointer.
CL_ERR_INVALID_HANDLE	On passing an invalid handle.
CL_ERR_NOT_INITIALIZED	If Buffer Management library is not initialized.
CL_ERR_INVALID_PARAMETER	On passing an invalid parameter.
CL_ERR_NO_MEMORY	On memory allocation failure.

Description:: This API is used to copy the numberOfBytes bytes starting at sourceMessageOffset offset in sourceMessage. The data will be copied in destinationMessage starting at write offset of the message.

Library Files:: ClBuffer

See Also: clBufferCreate(), clBufferReadOffsetGet(), clBufferDelete(), clBufferWriteOffsetGet(), clBufferToBufferCopy(), clBufferDuplicate()

ClRcT clBufferTrailerTrim	(	ClBufferHandleT	messageHandle,
		ClUint32T	numberOfBytes
	)

Trims the tail of the message.

Header File:: clBufferApi.h

Parameters

messageHandle	Handle to the message returned by clBufferCreate() API.
numberOfBytes	Number of bytes to delete from the tail of the message.

Return values

CL_OK	The API executed successfully.
CL_ERR_NULL_POINTER	On passing a NULL pointer.
CL_ERR_INVALID_HANDLE	On passing an invalid handle.
CL_ERR_NOT_INITIALIZED	If Buffer Management library is not initialized.
CL_ERR_INVALID_PARAMETER	On passing an invalid parameter.

Description:: This API is used to delete a specific number of bytes from tail of the message pointed by messageHandle. If the read/write offset is in the region being deleted, the read/write offset will be set to length of the buffer message, i.e, the end of the message, after performing the trim operation.

Library Files:: ClBuffer

See Also: clBufferCreate(), clBufferHeaderTrim(), clBufferDelete()

ClRcT clBufferUserToKernelCopy	(	ClBufferHandleT	userMessageHandle,
		ClBufferHandleT *	pKernelMessageHandle
	)

Copies message from user-space to kernel-space.

Header File:: clBufferApi.h

Note: This API is available only inside the kernel. It cannot be invoked from the user-space.

Parameters

userMessageHandle	Handle to message returned by clBufferCreate() API, which is to be copied into kernel space.
pKernelMessageHandle	(out) Pointer to variable of type ClBufferHandleT, in which the handle to message in the kernel space is returned.

Return values

CL_OK	The API executed successfully.
CL_ERR_NULL_POINTER	On passing a NULL pointer.
CL_ERR_INVALID_HANDLE	On passing an invalid handle.
CL_ERR_NOT_INITIALIZED	If Buffer Management library is not initialized.
CL_ERR_NO_MEMORY	On memory allocation failure.

Description:: This API is used to copy a message from user-space to kernel-space. The kernel space message will be created by the Buffer Management Library and the handle to created message will be returned. Write offset would be set to the end and read offset would point to the beginning of the kernel space message.

Library Files:: ClBuffer

See Also: clBufferCreate(), clBufferDelete(), clBufferKernelToUserCopy()

ClRcT clBufferWriteOffsetGet	(	ClBufferHandleT	messageHandle,
		ClUint32T *	pWriteOffset
	)

Returns current write offset of the message.

Header File:: clBufferApi.h

Parameters

messageHandle	Handle to the message returned by clBufferCreate API
pWriteOffset	Pointer to a variable of type ClUint32T, in which the current write offset is returned.

Return values

CL_OK	The API executed successfully.
CL_ERR_NULL_POINTER	On passing a NULL pointer.
CL_ERR_INVALID_HANDLE	On passing an invalid handle.
CL_ERR_NOT_INITIALIZED	If Buffer Management library is not initialized.

Description:: This API is used to retrieve the current write offset of the message. This offset is updated on invoking the clBufferNBytesWrite() API or directly through clBufferWriteOffsetSet().

Library Files:: ClBuffer

See Also: clBufferCreate(), clBufferReadOffsetGet(), clBufferDelete(), clBufferReadOffsetSet(), clBufferWriteOffsetSet(), clBufferTrailerTrim(), clBufferHeaderTrim()

ClRcT clBufferWriteOffsetSet	(	ClBufferHandleT	messageHandle,
		ClInt32T	newWriteOffset,
		ClBufferSeekTypeT	seekType
	)

Sets current write offset of the message.

Header File:: clBufferApi.h

Parameters

messageHandle	Handle to the message returned by clBufferCreate() API.
seekType	This parameter can accept the following values: `CL_BUFFER_SEEK_SET:` The write offset should be set to a position from the beginning of the message. `CL_BUFFER_SEEK_CUR:` The write offset should be set to a position from its current location. `CL_BUFFER_SEEK_END:` The write offset should be set to a position from the the end of the message.
newWriteOffset	The offset at which the current write offset is to be set. If seekType is set to CL_BUFFER_SEEK_SET then the value of newWriteOffset should be 0 or greater, for CL_BUFFER_SEEK_CUR it can be a positive of negative number and for CL_BUFFER_END it should be 0 or a negative number.

Return values

CL_OK	The API executed successfully.
CL_ERR_NULL_POINTER	On passing a NULL pointer.
CL_ERR_INVALID_HANDLE	On passing an invalid handle.
CL_ERR_NOT_INITIALIZED	If Buffer Management library is not initialized.
CL_ERR_INVALID_PARAMETER	If an invalid parameter is passed.

Description:: This API is used to set the current write offset of the buffer message pointed by messageHandle. The application wanting to write some data to the buffer message starting at a perticular point in the buffer message should set the buffer message's current write offset to that point and then do the write operation. This offset is also automatically updated on invoking the clBufferNBytesWrite().

Library Files:: ClBuffer

See Also: clBufferCreate(), clBufferWriteOffsetGet(), clBufferDelete(), clBufferReadOffsetSet(), clBufferTrailerTrim(), clBufferHeaderTrim(), clBufferNBytesRead()

Files

Classes

Typedefs

Enumerations

Functions

Detailed Description

Typedef Documentation

Enumeration Type Documentation

Function Documentation