svc_pollset(3) library routines for RPC servers

Other Alias

svc_dg_enablecache, svc_exit, svc_fdset, svc_freeargs, svc_getargs, svc_getreq_common, svc_getreq_poll, svc_getreqset, svc_getrpccaller, svc_run, svc_sendreply

SYNOPSIS

In rpc/rpc.h Ft int Fn svc_dg_enablecache SVCXPRT *xprt const unsigned cache_size Ft void Fn svc_exit void Ft bool_t Fn svc_freeargs const SVCXPRT *xprt const xdrproc_t inproc caddr_t in Ft bool_t Fn svc_getargs const SVCXPRT *xprt const xdrproc_t inproc caddr_t in Ft void Fn svc_getreq_common const int fd Ft void Fn svc_getreq_poll struct pollfd *pfdp const int pollretval Ft void Fn svc_getreqset fd_set * rdfds Ft struct netbuf * Fn svc_getrpccaller const SVCXPRT *xprt Ft struct cmsgcred * Fn __svc_getcallercreds const SVCXPRT *xprt Vt struct pollfd svc_pollset[FD_SETSIZE]; Ft void Fn svc_run void Ft bool_t Fn svc_sendreply SVCXPRT *xprt xdrproc_t outproc char *out

DESCRIPTION

These routines are part of the RPC library which allows C language programs to make procedure calls on other machines across the network.

These routines are associated with the server side of the RPC mechanism. Some of them are called by the server side dispatch function, while others (such as Fn svc_run ) are called when the server is initiated.

Routines

See rpc(3) for the definition of the Vt SVCXPRT data structure.

Fn svc_dg_enablecache
This function allocates a duplicate request cache for the service endpoint Fa xprt , large enough to hold Fa cache_size entries. Once enabled, there is no way to disable caching. This routine returns 0 if space necessary for a cache of the given size was successfully allocated, and 1 otherwise.
Fn svc_exit
This function, when called by any of the RPC server procedure or otherwise, causes Fn svc_run to return.

As currently implemented, Fn svc_exit zeroes the svc_fdset global variable. If RPC server activity is to be resumed, services must be reregistered with the RPC library either through one of the rpc_svc_create3 functions, or using Fn xprt_register . The Fn svc_exit function has global scope and ends all RPC server activity.

Vt fd_set Va svc_fdset
A global variable reflecting the RPC server's read file descriptor bit mask; it is suitable as an argument to the select(2) system call. This is only of interest if service implementors do not call Fn svc_run , but rather do their own asynchronous event processing. This variable is read-only (do not pass its address to select(2)!), yet it may change after calls to Fn svc_getreqset or any creation routines.
Fn svc_freeargs
A function macro that frees any data allocated by the RPC/XDR system when it decoded the arguments to a service procedure using Fn svc_getargs . This routine returns TRUE if the results were successfully freed, and FALSE otherwise.
Fn svc_getargs
A function macro that decodes the arguments of an RPC request associated with the RPC service transport handle Fa xprt . The Fa in argument is the address where the arguments will be placed; Fa inproc is the XDR routine used to decode the arguments. This routine returns TRUE if decoding succeeds, and FALSE otherwise.
Fn svc_getreq_common
This routine is called to handle a request on the given file descriptor.
Fn svc_getreq_poll
This routine is only of interest if a service implementor does not call Fn svc_run , but instead implements custom asynchronous event processing. It is called when poll(2) has determined that an RPC request has arrived on some RPC file descriptors; Fa pollretval is the return value from poll(2) and Fa pfdp is the array of Vt pollfd structures on which the poll(2) was done. It is assumed to be an array large enough to contain the maximal number of descriptors allowed.
Fn svc_getreqset
This routine is only of interest if a service implementor does not call Fn svc_run , but instead implements custom asynchronous event processing. It is called when poll(2) has determined that an RPC request has arrived on some RPC file descriptors; Fa rdfds is the resultant read file descriptor bit mask. The routine returns when all file descriptors associated with the value of Fa rdfds have been serviced.
Fn svc_getrpccaller
The approved way of getting the network address of the caller of a procedure associated with the RPC service transport handle Fa xprt .
Fn __svc_getcallercreds
Warning this macro is specific to Fx and thus not portable. This macro returns a pointer to a Vt cmsgcred structure, defined in In sys/socket.h , identifying the calling client. This only works if the client is calling the server over an AF_LOCAL socket.
Vt struct pollfd Va svc_pollset[FD_SETSIZE] ;
svc_pollset
is an array of Vt pollfd structures derived from svc_fdset[] It is suitable as an argument to the poll(2) system call. The derivation of svc_pollset from svc_fdset is made in the current implementation in Fn svc_run . Service implementors who do not call Fn svc_run and who wish to use this array must perform this derivation themselves.
Fn svc_run
This routine never returns. It waits for RPC requests to arrive, and calls the appropriate service procedure using Fn svc_getreq_poll when one arrives. This procedure is usually waiting for the poll(2) system call to return.
Fn svc_sendreply
Called by an RPC service's dispatch routine to send the results of a remote procedure call. The Fa xprt argument is the request's associated transport handle; Fa outproc is the XDR routine which is used to encode the results; and Fa out is the address of the results. This routine returns TRUE if it succeeds, FALSE otherwise.

AVAILABILITY

These functions are part of libtirpc.