Copyright 1989 AT&T
@(#)rpc_svc_calls 1.5 89/07/25 SMI;
Copyright (c) 1988 Sun Microsystems, Inc. - All Rights Reserved.
$NetBSD: rpc_svc_calls.3,v 1.1 2000/06/02 23:11:13 fvdl Exp $
$FreeBSD: releng/11.0/lib/libc/rpc/rpc_svc_calls.3 152720 2005-11-23 16:44:23Z ru $
.Dd May 3, 1993 .Dt RPC_SVC_CALLS 3 .Os .Sh NAME .Nm svc_dg_enablecache , .Nm svc_exit , .Nm svc_fdset , .Nm svc_freeargs , .Nm svc_getargs , .Nm svc_getreq_common , .Nm svc_getreq_poll , .Nm svc_getreqset , .Nm svc_getrpccaller , .Nm svc_pollset , .Nm svc_run , .Nm svc_sendreply .Nd library routines for RPC servers .Sh LIBRARY .Lb libc .Sh SYNOPSIS n 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" "void *out" .Sh DESCRIPTION These routines are part of the RPC library which allows C language programs to make procedure calls on other machines across the network.
p
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.
.Pp
In the current implementation, the service transport handle,
.Dv SVCXPRT ,
contains a single data area for decoding arguments and encoding results.
Therefore, this structure cannot be freely shared between threads that call
functions that do this.
Routines on this page that are affected by this
restriction are marked as unsafe for MT applications.
.Sh Routines
See
.Xr rpc 3
for the definition of the
.Vt SVCXPRT
data structure.
l -tag -width __svc_getcallercreds() t 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.
t Fn svc_exit This function, when called by any of the RPC server procedure or
otherwise, causes
.Fn svc_run
to return.
p As currently implemented, .Fn svc_exit zeroes the .Va 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 .Xr rpc_svc_create 3 functions, or using .Fn xprt_register . The .Fn svc_exit function has global scope and ends all RPC server activity. t Xo .Vt fd_set Va svc_fdset .Xc A global variable reflecting the RPC server's read file descriptor bit mask; it is suitable as an argument to the .Xr 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 .Xr select 2 ! ) , yet it may change after calls to .Fn svc_getreqset or any creation routines. t 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 .Dv TRUE if the results were successfully freed, and .Dv FALSE otherwise. t 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 .Dv TRUE if decoding succeeds, and .Dv FALSE otherwise. t Fn svc_getreq_common This routine is called to handle a request on the given file descriptor. t 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 .Xr poll 2 has determined that an RPC request has arrived on some RPC file descriptors; .Fa pollretval is the return value from .Xr poll 2 and .Fa pfdp is the array of .Vt pollfd structures on which the .Xr poll 2 was done. It is assumed to be an array large enough to contain the maximal number of descriptors allowed. t 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 .Xr 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. t 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 . t Fn __svc_getcallercreds .Em Warning : this macro is specific to .Fx and thus not portable. This macro returns a pointer to a .Vt cmsgcred structure, defined in n sys/socket.h , identifying the calling client. This only works if the client is calling the server over an .Dv AF_LOCAL socket. t Xo .Vt struct pollfd Va svc_pollset[FD_SETSIZE] ; .Xc .Va svc_pollset is an array of .Vt pollfd structures derived from .Va svc_fdset[] . It is suitable as an argument to the .Xr poll 2 system call. The derivation of .Va svc_pollset from .Va 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. t 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 .Xr poll 2 system call to return. t 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 .Dv TRUE if it succeeds, .Dv FALSE otherwise. .El .Sh SEE ALSO .Xr poll 2 , .Xr select 2 , .Xr rpc 3 , .Xr rpc_svc_create 3 , .Xr rpc_svc_err 3 , .Xr rpc_svc_reg 3