VxWorks Reference Manual : Wind Foundation Classes
VXWSm - support for shared memory objects
VXWSmBSem::VXWSmBSem( ) - create and initialize binary shared-memory semaphore (VxMP Option)
VXWSmBSem::VXWSmBSem( ) - build a binary shared-memory semaphore object (VxMP Option)
VXWSmCSem::VXWSmCSem( ) - create and initialize a shared memory counting semaphore (VxMP Option)
VXWSmCSem::VXWSmCSem( ) - build a shared-memory counting semaphore object (VxMP Option)
VXWSmMsgQ::VXWSmMsgQ( ) - create and initialize a shared-memory message queue (VxMP Option)
VXWSmMemPart::VXWSmMemPart( ) - create a shared memory partition (VxMP Option)
VXWSmMemBlock::VXWSmMemBlock( ) - allocate a block of memory from the shared memory system partition (VxMP Option)
VXWSmMemBlock::VXWSmMemBlock( ) - allocate memory for an array from the shared memory system partition (VxMP Option)
VXWSmMemBlock::~VXWSmMemBlock( ) - free a shared memory system partition block of memory (VxMP Option)
VXWSmMemBlock::baseAddress( ) - address of shared-memory block
This library defines wrapper classes for VxWorks shared-memory objects: VXWSmBSem (shared-memory binary semaphores), VXWSmCSem (shared-memory counting semaphores), VXWSmMsgQ (shared-memory message queues), VXWSmMemPart (shared memory partitions), and VXWSmMemBlock (shared memory blocks).
All of the shared-memory object wrappers inherit the public members of VXWSmNameLib.
The VXWSmBSem and VXWSmCSem classes also inherit from VXWSem; VXWSmMsgQ also inherits from VXWMsgQ; VXWSmMemPart also inherits from VXWMemPArt.
vxwSmLib.h
VXWSm, vxwSmNameLib, vxwMsgQLib, vxwMemPartLib, vxwSemLib, VxWorks Programmer's Guide: Shared-Memory Objects
VXWSmBSem::VXWSmBSem( ) - create and initialize binary shared-memory semaphore (VxMP Option)
VXWSmBSem ( int opts, SEM_B_STATE istate, char * name = 0 )
This routine allocates and initializes a shared memory binary semaphore. The semaphore is initialized to an initial state istate of either SEM_FULL (available) or SEM_EMPTY (not available). The shared semaphore structure is allocated from the shared semaphore dedicated memory partition. Use the optional name argument to identify the new semaphore by name.
The queuing style for blocked tasks is set by opts; the only supported queuing style for shared memory semaphores is first-in-first-out, selected by SEM_Q_FIFO.
The maximum number of shared memory semaphores (binary plus counting) that can be created is SM_OBJ_MAX_SEM, defined in configAll.h.
This routine depends on code distributed as a component of the unbundled shared memory support option, VxMP.
N/A.
S_smMemLib_NOT_ENOUGH_MEMORY
S_semLib_INVALID_QUEUE_TYPE
S_semLib_INVALID_STATE
S_smObjLib_LOCK_TIMEOUT
VXWSm, vxwSemLib, vxwSmNameLib
VXWSmBSem::VXWSmBSem( ) - build a binary shared-memory semaphore object (VxMP Option)
VXWSmBSem ( char * name, int waitType )
This routine builds a shared-memory binary semaphore object around an existing named shared-memory semaphore. The name argument identifies the existing semaphore; waitType specifies whether to wait if the desired name is not found in the shared-memory name database; see VXWSmName::nameGet( ).
Use this routine to take advantage of the VXWSmBSem class while working with semaphores created by some other means (for example, previously existing C code).
N/A.
VXWSmCSem::VXWSmCSem( ) - create and initialize a shared memory counting semaphore (VxMP Option)
VXWSmCSem ( int opts, int icount, char * name = 0 )
This routine allocates and initializes a shared memory counting semaphore. The initial count value of the semaphore (the number of times the semaphore must be taken before it can be given) is specified by icount.
The queuing style for blocked tasks is set by opts; the only supported queuing style for shared memory semaphores is first-in-first-out, selected by SEM_Q_FIFO.
The maximum number of shared memory semaphores (binary plus counting) that can be created is SM_OBJ_MAX_SEM, defined in configAll.h.
This routine depends on code distributed as a component of the unbundled shared memory support option, VxMP.
N/A.
S_smMemLib_NOT_ENOUGH_MEMORY
S_semLib_INVALID_QUEUE_TYPE
S_smObjLib_LOCK_TIMEOUT
VXWSm, vxwSemLib, vxwSmNameLib
VXWSmCSem::VXWSmCSem( ) - build a shared-memory counting semaphore object (VxMP Option)
VXWSmCSem ( char * name, int waitType )
This routine builds a shared-memory semaphore object around an existing named shared-memory counting semaphore. The name argument identifies the existing semaphore, and waitType specifies whether to wait if the desired name is not found in the shared-memory name database; see VXWSmName::nameGet( ).
Use this routine to take advantage of the VXWSmBSem class while working with semaphores created by some other means (for example, previously existing C code).
N/A.
VXWSmMsgQ::VXWSmMsgQ( ) - create and initialize a shared-memory message queue (VxMP Option)
VXWSmMsgQ ( int maxMsgs, int maxMsgLength, int options )
This routine creates a shared memory message queue capable of holding up to maxMsgs messages, each up to maxMsgLength bytes long. The queue can only be created with the option MSG_Q_FIFO (0), thus queuing pended tasks in FIFO order.
If there is insufficient memory to store the message queue structure in the shared memory message queue partition or if the shared memory system pool cannot handle the requested message queue size, shared memory message queue creation fails with errno set to S_smMemLib_NOT_ENOUGH_MEMORY. This problem can be solved by incrementing the SM_OBJ_MAX_MSG_Q value in configAll.h and/or the size of memory dedicated to shared-memory objects SM_OBJ_MEM_SIZE in config.h.
This routine depends on code distributed as a component of the unbundled shared memory objects support option, VxMP.
N/A.
S_smMemLib_NOT_ENOUGH_MEMORY
S_intLib_NOT_ISR_CALLABLE
S_msgQLib_INVALID_QUEUE_TYPE
S_smObjLib_LOCK_TIMEOUT
VXWSm, vxwMsgQLib, vxwSmNameLib
VXWSmMemPart::VXWSmMemPart( ) - create a shared memory partition (VxMP Option)
VXWSmMemPart ( char * pool, unsigned poolSize )
This routine creates a shared memory partition that can be used by tasks on all CPUs in the system to manage memory blocks . Because the VXWSmMemPart class inherits from VXWMemPart, you can use the general-purpose methods in that class to manage the partition (that is, to allocate and free memory blocks in the partition).
pool is a pointer to the global address of shared memory dedicated to the partition. The memory area where pool points must be in the same address space as the shared memory anchor and shared memory pool.
poolSize is the size in bytes of shared memory dedicated to the partition.
The descriptor for the new partition is allocated out of an internal dedicated shared memory partition. The maximum number of partitions that can be created is SM_OBJ_MAX_MEM_PART, defined in configAll.h.
Memory pool size is rounded down to a 16-byte boundary.
This routine depends on code distributed as a component of the unbundled shared memory objects support option, VxMP.
N/A.
S_memLib_NOT_ENOUGH_MEMORY
S_smObjLib_LOCK_TIMEOUT
VXWSm, vxwMemPartLib, vxwSmNameLib
VXWSmMemBlock::VXWSmMemBlock( ) - allocate a block of memory from the shared memory system partition (VxMP Option)
VXWSmMemBlock ( int nBytes )
This routine allocates, from the shared memory system partition, a block of memory whose size is equal to or greater than nBytes. The local address of the allocated shared memory block can be obtained from VXWSmMemBlock::baseAddress( ).
This routine depends on code distributed as a component of the unbundled shared memory objects support option, VxMP.
N/A.
S_memLib_NOT_ENOUGH_MEMORY
S_smObjLib_LOCK_TIMEOUT
VXWSmMemBlock::VXWSmMemBlock( ) - allocate memory for an array from the shared memory system partition (VxMP Option)
VXWSmMemBlock ( int nElems, int sizeOfElem )
This routine allocates a block of memory for an array that contains nElems elements of size sizeOfElem from the shared memory system partition. The local address of the allocated shared memory block can be obtained from VXWSmMemBlock::baseAddress( ).
This routine depends on code distributed as a component of the unbundled shared memory objects support option, VxMP.
A pointer to the block, or NULL if the memory cannot be allocated.
S_memLib_NOT_ENOUGH_MEMORY
S_smObjLib_LOCK_TIMEOUT
VXWSmMemBlock::~VXWSmMemBlock( ) - free a shared memory system partition block of memory (VxMP Option)
virtual ~VXWSmMemBlock ()
This routine returns a VXWSmMemBlock shared-memory block to the free-memory pool in the shared-memory system partition.
This routine depends on code distributed as a component of the unbundled shared memory objects support option, VxMP.
N/A.
S_smObjLib_LOCK_TIMEOUT
VXWSmMemBlock::VXWSmMemBlock( )
VXWSmMemBlock::baseAddress( ) - address of shared-memory block
void * baseAddress ()
This routine reports the local address of a block of shared memory managed as a VXWSmMemBlock object.
Local address of memory block in shared-memory system partition.