BSP Developer's Guide

H
Implementing a MUX-Based Network Interface Driver
typedef struct net_protocol
{
NODE node; /* How we stay in a list. */
char name[32]; /* String name for this protocol. */
long type; /* Protocol type from RFC 1700 */
int flags; /* Is protocol in a promiscuous mode? */
BOOL (*stackRcvRtn) (void *, long, M_BLK_ID, M_BLK_ID, void*);
/* The routine to call when we get */
/* a packet. */
STATUS (*stackShutdownRtn) (void*, void*);
/* The routine to call to shutdown */
/* the protocol stack. */
STATUS (*stackTxRestartRtn) (void*, void*);
/* Callback for restarting on blocked tx. */
void (*stackErrorRtn) (END_OBJ*, END_ERR*, void*);
/* Callback for device errors. */
void* pSpare; /* Spare pointer that can be passed to */
/* the protocol. */
} NET_PROTOCOL;
Passing a Packet Up to the Protocol: stackRcvRtn( )
Each protocol must provide the MUX with a routine that the MUX can use to pass
packets up to the protocol. This routine must take the following form:
void stackRcvRtn
(
void* pCookie, /* returned by muxBind() call */
long type, /* protocol type from RFC 1700 */
M_BLK_ID pNetBuff, /* packet with link level info */
LL_HDR_INFO* pLinkHdr, /* link-level header info structure */
void* pSpare /* a void* the protocol can use to get info */
/* on receive. This was passed to muxBind().*/
)
H
Your protocol must declare its stackRcvRtn( ) as void. Thus, this function returns
no value.
The parameters are:
pCookie
Expects the pointer returned from the muxBind( ) call. This pointer identifies
the device to which the MUX has bound this protocol.
type
Expects the protocol type from RFC1700 or the SAP.
pNetBuff
Expects a pointer to an mBlk structure that contains the packet data and the
link-level information.
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