vrpn_PeerMutex类 参考

#include <vrpn_Mutex.h>

vrpn_PeerMutex 的协作图:

类
struct	mutexCallback
struct	peerData

Public 成员函数
	vrpn_PeerMutex (const char *name, int port, const char *NICaddress=NULL)
	This constructor opens a new connection/port for the mutex.
	~vrpn_PeerMutex (void)
	If isHeldLocally(), calls release().
vrpn_bool	isAvailable (void) const
vrpn_bool	isHeldLocally (void) const
vrpn_bool	isHeldRemotely (void) const
int	numPeers (void) const
void	mainloop (void)
void	request (void)
void	release (void)
vrpn_bool	addPeer (const char *stationName)
	Takes a VRPN station name of the form "<host>:<port>".
vrpn_bool	addRequestGrantedCallback (void *userdata, int(*)(void *))
	These callbacks are triggered when OUR request is granted.
vrpn_bool	addRequestDeniedCallback (void *userdata, int(*)(void *))
	These callbacks are triggered when OUR request is denied.
vrpn_bool	addTakeCallback (void *userdata, int(*)(void *))
vrpn_bool	addReleaseCallback (void *userdata, int(*)(void *))

Protected 类型
enum	state { OURS , REQUESTING , AVAILABLE , HELD_REMOTELY }

Protected 成员函数
void	sendRequest (vrpn_Connection *)
void	sendRelease (vrpn_Connection *)
void	sendGrantRequest (vrpn_Connection *, vrpn_uint32 IPnumber, vrpn_uint32 PortNumber)
void	sendDenyRequest (vrpn_Connection *, vrpn_uint32 IPnumber, vrpn_uint32 PortNumber)
void	triggerGrantCallbacks (void)
void	triggerDenyCallbacks (void)
void	triggerTakeCallbacks (void)
void	triggerReleaseCallbacks (void)
void	checkGrantMutex (void)
void	init (const char *name)
	vrpn_PeerMutex (const char *name, vrpn_Connection *c)

静态 Protected 成员函数
static int VRPN_CALLBACK	handle_request (void *, vrpn_HANDLERPARAM)
static int VRPN_CALLBACK	handle_release (void *, vrpn_HANDLERPARAM)
static int VRPN_CALLBACK	handle_grantRequest (void *, vrpn_HANDLERPARAM)
static int VRPN_CALLBACK	handle_denyRequest (void *, vrpn_HANDLERPARAM)
static int VRPN_CALLBACK	handle_losePeer (void *, vrpn_HANDLERPARAM)

Protected 属性
char *	d_mutexName
state	d_state
int	d_numPeersGrantingLock
vrpn_Connection *	d_server
	Receive on this connection.
vrpn_Connection **	d_peer
	Send on these connections to other Mutex's well-known-ports.
int	d_numPeers
int	d_numConnectionsAllocated
	Dynamic array size for d_peer and d_peerGrantedLock.
vrpn_uint32	d_myIP
vrpn_uint32	d_myPort
vrpn_uint32	d_holderIP
vrpn_int32	d_holderPort
vrpn_int32	d_myId
vrpn_int32	d_request_type
vrpn_int32	d_release_type
vrpn_int32	d_grantRequest_type
vrpn_int32	d_denyRequest_type
mutexCallback *	d_reqGrantedCB
mutexCallback *	d_reqDeniedCB
mutexCallback *	d_takeCB
mutexCallback *	d_releaseCB
peerData *	d_peerData

详细描述

vrpn_PeerMutex

This class provides distributed mutual exclusion between every instance with the same name for which addPeer() has been called. If a process calls request() when isAvailable() returns true, the mutex will attempt to secure a lock to whatever resource it is governing; either RequestGranted or RequestDenied callbacks will be triggered. If RequestGranted callbacks are triggered, the process has the lock until it explicitly calls release() (and can verify this by checking isHeldLocally()). Once the lock-owner calls release(), Release callbacks at every peer will be triggered.

Like most vrpn classes, the mainloop() must be called frequently.

Note that none of isAvailable(), isHeldLocally(), and isHeldRemotely() are true between when request() is called and either RequestGranted or RequestDenied callbacks are triggered.

构造及析构函数说明

vrpn_PeerMutex() [1/2]

vrpn_PeerMutex	(	const char *	name,
		int	port,
		const char *	NICaddress = NULL )

This constructor opens a new connection/port for the mutex.

~vrpn_PeerMutex()

~vrpn_PeerMutex

(

void

)

If isHeldLocally(), calls release().

vrpn_PeerMutex() [2/2]

vrpn_PeerMutex ( const char * name, vrpn_Connection * c )

protected

This constructor reuses a SERVER connection for the mutex. BUG BUG BUG - do not use this constructor; it does not reliably resolve race conditions.

成员函数说明

addPeer()

vrpn_bool addPeer

(

const char *

stationName

)

Takes a VRPN station name of the form "<host>:<port>".

addReleaseCallback()

vrpn_bool addReleaseCallback	(	void *	userdata,
		int(*	)(void *) )

These callbacks are triggered when ANY peer releases the mutex.

addRequestDeniedCallback()

vrpn_bool addRequestDeniedCallback	(	void *	userdata,
		int(*	)(void *) )

These callbacks are triggered when OUR request is denied.

addRequestGrantedCallback()

vrpn_bool addRequestGrantedCallback	(	void *	userdata,
		int(*	)(void *) )

These callbacks are triggered when OUR request is granted.

addTakeCallback()

vrpn_bool addTakeCallback	(	void *	userdata,
		int(*	)(void *) )

These callbacks are triggered when ANY peer gets the mutex. (If several peers are competing for the mutex, and the implementation issues multiple "grants", these callbacks will only be triggered once between triggerings of ReleaseCallbacks.)

isAvailable()

vrpn_bool isAvailable

(

void

)

const

True from when release() is called or we receive a release message from another process until request() is called or we grant the lock to another process in response to its request message.

isHeldLocally()

vrpn_bool isHeldLocally

(

void

)

const

True from when RequestGranted callbacks are triggered until release() is called.

isHeldRemotely()

vrpn_bool isHeldRemotely

(

void

)

const

True from when we grant the lock to another process in response to its request message until we receive a release message from another process.

release()

void release

(

void

)

Release the distributed lock. Does nothing if !isHeldLocally() and there isn't a request pending.

request()

void request

(

void

)

Request the distributed lock. Does not request the lock if !isAvailable(), instead automatically triggering DeniedCallbacks.

类成员变量说明

d_numConnectionsAllocated

int d_numConnectionsAllocated

protected

Dynamic array size for d_peer and d_peerGrantedLock.

d_numPeersGrantingLock

int d_numPeersGrantingLock

protected

Counts the number of "grants" we've received after issuing a request; when this reaches d_numPeers, the lock is ours.

d_peer

vrpn_Connection** d_peer

protected

Send on these connections to other Mutex's well-known-ports.

d_peerData

peerData* d_peerData

protected

Needed only to clean up when a peer shuts down (mid-request). It isn't currently feasible to have all this data, so instead we abort requests that were interrupted by a shutdown.

d_server

vrpn_Connection* d_server

protected

Receive on this connection.

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该类的文档由以下文件生成:

• simulink/vrpn/vrpn_Mutex.h