com.sun.rtsjx
Class SharedMemoryMapper

java.lang.Object
  com.sun.rtsjx.CoreRawMemoryType
      com.sun.rtsjx.SharedMemoryMapper

All Implemented Interfaces:

PhysicalMemoryMapper, javax.realtime.PhysicalMemoryTypeFilter

public class SharedMemoryMapper
extends CoreRawMemoryType
implements PhysicalMemoryMapper

Shared memory support.

PhysicalMemoryManager.SHARED provides the common addConstraints call

new instances are created for each physical memory request.

Constructor Summary

SharedMemoryMapper()

SharedMemoryMapper(long base, long size)

SharedMemoryMapper(java.lang.Object[] param)

Method Summary

void	addConstraints(PhysicalMemoryRequest request) Add new constraints to a physical memory request.
void	checkMapperConstraints(PhysicalMemoryRequest request) Check the constraints due to the mapper itself.
long	get_mapped_address() Get the mapped address, or 0 if unmapped.
int	get_shared_id() Get the shared identifier.
boolean	isCompatibleWithPhysicalMemory() Returns true if this mapper is compatible with ImmortalPhysicalMemory, LTPhysicalMemory and VTPhysicalMemory.
long	map(PhysicalMemoryRequest request) Map the shared memory.
void	unmap(PhysicalMemoryRequest request) Undo a mapping.

Methods inherited from class com.sun.rtsjx.CoreRawMemoryType

checkConstraints, contains, find, getVMAttributes, getVMFlags, initialize, isPresent, isRemovable, onInsertion, onInsertion, onRemoval, onRemoval, unregisterInsertionEvent, unregisterRemovalEvent, vFind

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SharedMemoryMapper

public SharedMemoryMapper()

SharedMemoryMapper

public SharedMemoryMapper(long base,
                          long size)

SharedMemoryMapper

public SharedMemoryMapper(java.lang.Object[] param)

Method Detail

get_mapped_address

public long get_mapped_address()

Description copied from interface: PhysicalMemoryMapper

Get the mapped address, or 0 if unmapped.

Specified by:

get_mapped_address in interface PhysicalMemoryMapper

Returns:

the mapped address, or 0 if unmapped.

addConstraints

public void addConstraints(PhysicalMemoryRequest request)
                    throws java.lang.SecurityException,
                           javax.realtime.OffsetOutOfBoundsException,
                           javax.realtime.SizeOutOfBoundsException,
                           javax.realtime.UnsupportedPhysicalMemoryException,
                           javax.realtime.MemoryTypeConflictException,
                           java.lang.OutOfMemoryError

Description copied from class: CoreRawMemoryType

Add new constraints to a physical memory request.

Overrides:

addConstraints in class CoreRawMemoryType

Parameters:

request - null or PhysicalMemoryRequest containing the previously parsed constraints.

Throws:

java.lang.SecurityException - Thrown if application doesn't have permissions to access physical memory, the specified range of addresses, or the given type of memory.

javax.realtime.OffsetOutOfBoundsException - Thrown if the address is invalid.

javax.realtime.SizeOutOfBoundsException - Thrown if the size is negative or extends into an invalid range of memory.

javax.realtime.UnsupportedPhysicalMemoryException - Thrown if the underlying hardware does not support the given type, or if no matching PhysicalMemoryTypeFilter has been registered with the PhysicalMemoryManager.

javax.realtime.MemoryTypeConflictException - Thrown if the specified base does not point to memory that matches the request type, or if type specifies incompatible memory attributes.

java.lang.OutOfMemoryError - Thrown if the requested type of memory exists, but there is not enough of it free to satisfy the request.

See Also:

PhysicalMemoryRequest

checkMapperConstraints

public void checkMapperConstraints(PhysicalMemoryRequest request)
                            throws javax.realtime.SizeOutOfBoundsException,
                                   javax.realtime.MemoryTypeConflictException

Description copied from interface: PhysicalMemoryMapper

Check the constraints due to the mapper itself.

The default implementation does nothing.

Specified by:

checkMapperConstraints in interface PhysicalMemoryMapper

Parameters:

request - constraints issued from the parsing of a memory type.

Throws:

javax.realtime.SizeOutOfBoundsException - Thrown if the size is negative or extends into an invalid range of memory.

javax.realtime.MemoryTypeConflictException - Thrown if the specified base does not point to memory that matches the request type, or if type specifies incompatible memory attributes.

get_shared_id

public int get_shared_id()

Get the shared identifier.

It is the result of the shmget UNIX call.

map

public long map(PhysicalMemoryRequest request)
         throws javax.realtime.OffsetOutOfBoundsException,
                javax.realtime.SizeOutOfBoundsException,
                javax.realtime.MemoryTypeConflictException,
                java.lang.OutOfMemoryError

Map the shared memory.

request.initial_pbase is used as the shared memory key.

request.get_len() provides the requested size.

request.get_flags() provides the flags for both the shmget and the shmat calls.

If the key is not -1, shmget and shmat are performed for each map call.

If the key is equal to -1, IPC_PRIVATE shared memory is created with shmget. Once successful, the same share memory identifier is reused and only shmat is called.

Specified by:

map in interface PhysicalMemoryMapper

Parameters:

request - constraints issued from the parsing of a memory type.

Throws:

javax.realtime.OffsetOutOfBoundsException - Thrown if the address is invalid.

javax.realtime.SizeOutOfBoundsException - Thrown if the size is negative or extends into an invalid range of memory.

javax.realtime.MemoryTypeConflictException - Thrown if the specified base does not point to memory that matches the request type, or if type specifies incompatible memory attributes.

java.lang.OutOfMemoryError - Thrown if the requested type of memory exists, but there is not enough of it free to satisfy the request.

unmap

public void unmap(PhysicalMemoryRequest request)

Description copied from interface: PhysicalMemoryMapper

Undo a mapping.

Specified by:

unmap in interface PhysicalMemoryMapper

Parameters:

request - constraints issued from the parsing of a memory type.

isCompatibleWithPhysicalMemory

public boolean isCompatibleWithPhysicalMemory()

Description copied from interface: PhysicalMemoryMapper

Returns true if this mapper is compatible with ImmortalPhysicalMemory, LTPhysicalMemory and VTPhysicalMemory. false otherwise

Specified by:

isCompatibleWithPhysicalMemory in interface PhysicalMemoryMapper