ACE_MEM_IO Class Reference

Defines the methods for the ACE shared memory wrapper I/O routines (e.g., send/recv). The shared memory transport uses ACE_SOCK_* class to implement the signaling mechanism so we can easily use the new mechanism with the Reactor pattern (which uses select under the hood.) ACE_MEM_Acceptor and ACE_MEM_Connector are used to establish connections. When a connection is established, ACE_MEM_Acceptor creates the MMAP file for data exchange and sends the location of the file (complete path name) to ACE_MEM_Connector thru the socket. ACE_MEM_Connector then reads the location of the file off the socket and opens up the same MMAP file. ACE_MEM_Stream at each side then contains a reference to the ACE_Mallo object using the same MMAP file. When sending information using methods provided in this class, ACE_MEM_IO requests a chunk of memory from the MALLOC_TYPE object, copy the data into the shared memory and send the memory offset (from the start of the ACE_Malloc) across the socket. This action also servers as a signal to the other end. The receiving side then reverses the procedures and copies the information into user buffer. More...

#include <MEM_IO.h>

Inheritance diagram for ACE_MEM_IO:

Collaboration diagram for ACE_MEM_IO:

Public Types
enum	Signal_Strategy { Reactive , MT }

Public Member Functions
	ACE_MEM_IO ()
	Constructor.
	~ACE_MEM_IO ()
	Destructor.
int	init (const ACE_TCHAR *name, ACE_MEM_IO::Signal_Strategy type=ACE_MEM_IO::Reactive, ACE_MEM_SAP::MALLOC_OPTIONS *options=0)
int	fini ()
ssize_t	send (const void *buf, size_t n, int flags)
ssize_t	recv (void *buf, size_t n, int flags)
	Recv an n byte buffer from the shm_malloc_ thru connected socket.
ssize_t	send (const void *buf, size_t n)
ssize_t	recv (void *buf, size_t n)
	Recv an n byte buffer from the shm_malloc_ thru connected socket.
ssize_t	send (const void *buf, size_t n, const ACE_Time_Value *timeout)
ssize_t	send (const void *buf, size_t n, int flags, const ACE_Time_Value *timeout)
ssize_t	send (const ACE_Message_Block *message_block, const ACE_Time_Value *timeout)
ssize_t	recv (void *buf, size_t n, const ACE_Time_Value *timeout)
ssize_t	recv (void *buf, size_t n, int flags, const ACE_Time_Value *timeout)
void	dump () const
	Dump the state of an object.
Public Member Functions inherited from ACE_SOCK
int	set_option (int level, int option, void *optval, int optlen) const
	Wrapper around the setsockopt system call.
int	get_option (int level, int option, void *optval, int *optlen) const
	Wrapper around the getsockopt system call.
int	close ()
int	get_local_addr (ACE_Addr &) const
int	get_remote_addr (ACE_Addr &) const
void	dump () const
	Dump the state of an object.
int	open (int type, int protocol_family, int protocol, int reuse_addr)
	Wrapper around the BSD-style socket system call (no QoS).
int	open (int type, int protocol_family, int protocol, ACE_Protocol_Info *protocolinfo, ACE_SOCK_GROUP g, u_long flags, int reuse_addr)
	Wrapper around the QoS-enabled WSASocket function.
Public Member Functions inherited from ACE_IPC_SAP
int	control (int cmd, void *) const
	Interface for <ioctl>.
int	enable (int value) const
int	disable (int value) const
ACE_HANDLE	get_handle () const
	Get the underlying handle.
void	set_handle (ACE_HANDLE handle)
	Set the underlying handle.
void	dump () const
	Dump the state of an object.

Public Attributes
	ACE_ALLOC_HOOK_DECLARE
	Declare the dynamic allocation hooks.
Public Attributes inherited from ACE_SOCK
	ACE_ALLOC_HOOK_DECLARE
	Declare the dynamic allocation hooks.
Public Attributes inherited from ACE_IPC_SAP
	ACE_ALLOC_HOOK_DECLARE
	Declare the dynamic allocation hooks.

Private Member Functions
ssize_t	fetch_recv_buf (int flag, const ACE_Time_Value *timeout)

Private Attributes
ACE_MEM_SAP *	deliver_strategy_
	Actual deliverying mechanism.
ACE_MEM_SAP_Node *	recv_buffer_
	Internal pointer for support recv/send.
ssize_t	buf_size_
	Record the current total buffer size of <recv_buffer_>.
ssize_t	cur_offset_
	Record the current read pointer location in <recv_buffer_>.

Additional Inherited Members
Protected Member Functions inherited from ACE_SOCK
	ACE_SOCK (int type, int protocol_family, int protocol=0, int reuse_addr=0)
	ACE_SOCK (int type, int protocol_family, int protocol, ACE_Protocol_Info *protocolinfo, ACE_SOCK_GROUP g, u_long flags, int reuse_addr)
	ACE_SOCK ()
	~ACE_SOCK ()=default
	Protected destructor.
Protected Member Functions inherited from ACE_IPC_SAP
	ACE_IPC_SAP ()
	Default constructor.
	~ACE_IPC_SAP ()
	Protected destructor.

Detailed Description

Defines the methods for the ACE shared memory wrapper I/O routines (e.g., send/recv). The shared memory transport uses ACE_SOCK_* class to implement the signaling mechanism so we can easily use the new mechanism with the Reactor pattern (which uses select under the hood.) ACE_MEM_Acceptor and ACE_MEM_Connector are used to establish connections. When a connection is established, ACE_MEM_Acceptor creates the MMAP file for data exchange and sends the location of the file (complete path name) to ACE_MEM_Connector thru the socket. ACE_MEM_Connector then reads the location of the file off the socket and opens up the same MMAP file. ACE_MEM_Stream at each side then contains a reference to the ACE_Mallo object using the same MMAP file. When sending information using methods provided in this class, ACE_MEM_IO requests a chunk of memory from the MALLOC_TYPE object, copy the data into the shared memory and send the memory offset (from the start of the ACE_Malloc) across the socket. This action also servers as a signal to the other end. The receiving side then reverses the procedures and copies the information into user buffer.

Member Enumeration Documentation

Signal_Strategy

enum ACE_MEM_IO::Signal_Strategy

Enumerator
Reactive
MT

Constructor & Destructor Documentation

ACE_MEM_IO()

ACE_MEM_IO::ACE_MEM_IO ( )

inline

Constructor.

~ACE_MEM_IO()

ACE_MEM_IO::~ACE_MEM_IO ( )

inline

Destructor.

Member Function Documentation

dump()

void ACE_MEM_IO::dump

(

)

const

Dump the state of an object.

fetch_recv_buf()

ssize_t ACE_MEM_IO::fetch_recv_buf ( int flag, const ACE_Time_Value * timeout )

inlineprivate

Return the local endpoint port number. Returns 0 if successful, else -1.

fini()

int ACE_MEM_IO::fini

(

)

Finalizing the MEM_IO object. This method doesn't invoke the <remove> method.

init()

int ACE_MEM_IO::init	(	const ACE_TCHAR *	name,
		ACE_MEM_IO::Signal_Strategy	type = ACE_MEM_IO::Reactive,
		ACE_MEM_SAP::MALLOC_OPTIONS *	options = 0 )

Initialize the MEM_SAP object.

recv() [1/4]

ssize_t ACE_MEM_IO::recv ( void * buf, size_t n )

inline

Recv an n byte buffer from the shm_malloc_ thru connected socket.

recv() [2/4]

ssize_t ACE_MEM_IO::recv ( void * buf, size_t n, const ACE_Time_Value * timeout )

inline

Wait up to timeout amount of time to receive up to n bytes into buf from <handle> (uses the <recv> call). If <recv> times out a -1 is returned with errno == ETIME. If it succeeds the number of bytes received is returned.

recv() [3/4]

ssize_t ACE_MEM_IO::recv ( void * buf, size_t n, int flags )

inline

Recv an n byte buffer from the shm_malloc_ thru connected socket.

recv() [4/4]

ssize_t ACE_MEM_IO::recv ( void * buf, size_t n, int flags, const ACE_Time_Value * timeout )

inline

Wait up to timeout amount of time to receive up to n bytes into buf from <handle> (uses the <recv> call). If <recv> times out a -1 is returned with errno == ETIME. If it succeeds the number of bytes received is returned.

send() [1/5]

ssize_t ACE_MEM_IO::send	(	const ACE_Message_Block *	message_block,
		const ACE_Time_Value *	timeout )

Wait to to timeout amount of time to send the message_block. If <send> times out a -1 is returned with errno == ETIME. If it succeeds the number of bytes sent is returned.

send() [2/5]

ssize_t ACE_MEM_IO::send ( const void * buf, size_t n )

inline

Send an n byte buffer to the other process using shm_malloc_ connected thru the socket.

send() [3/5]

ssize_t ACE_MEM_IO::send ( const void * buf, size_t n, const ACE_Time_Value * timeout )

inline

Wait to to timeout amount of time to send up to n bytes into buf from <handle> (uses the <send> call). If <send> times out a -1 is returned with errno == ETIME. If it succeeds the number of bytes sent is returned.

send() [4/5]

ssize_t ACE_MEM_IO::send ( const void * buf, size_t n, int flags )

inline

Send an n byte buffer to the other process using shm_malloc_ connected thru the socket.

send() [5/5]

ssize_t ACE_MEM_IO::send ( const void * buf, size_t n, int flags, const ACE_Time_Value * timeout )

inline

Wait to to timeout amount of time to send up to n bytes into buf from <handle> (uses the <send> call). If <send> times out a -1 is returned with errno == ETIME. If it succeeds the number of bytes sent is returned.

Member Data Documentation

ACE_ALLOC_HOOK_DECLARE

ACE_MEM_IO::ACE_ALLOC_HOOK_DECLARE

Declare the dynamic allocation hooks.

buf_size_

ssize_t ACE_MEM_IO::buf_size_

private

Record the current total buffer size of <recv_buffer_>.

cur_offset_

ssize_t ACE_MEM_IO::cur_offset_

private

Record the current read pointer location in <recv_buffer_>.

deliver_strategy_

ACE_MEM_SAP* ACE_MEM_IO::deliver_strategy_

private

Actual deliverying mechanism.

recv_buffer_

ACE_MEM_SAP_Node* ACE_MEM_IO::recv_buffer_

private

Internal pointer for support recv/send.

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The documentation for this class was generated from the following files:

• MEM_IO.h
• MEM_IO.cpp
• MEM_IO.inl