rpc_svc_calls(3)

NAME

svc_dg_enablecache, svc_exit, svc_fdset, svc_freeargs,

svc_getargs,
svc_getreq_common, svc_getreq_poll, svc_getreqset,

svc_getrpccaller,
svc_pollset, svc_run, svc_sendreply - library routines for

RPC servers

LIBRARY

Standard C Library (libc, -lc)

SYNOPSIS

#include <rpc/rpc.h>
int
svc_dg_enablecache(SVCXPRT     *xprt,     const     unsigned
cache_size);
void
svc_exit(void);
bool_t
svc_freeargs(const SVCXPRT *xprt,  const  xdrproc_t  inproc,
caddr_t in);
bool_t
svc_getargs(const  SVCXPRT  *xprt,  const  xdrproc_t inproc,
caddr_t in);
void
svc_getreq_common(const int fd);
void
svc_getreq_poll(struct pollfd *pfdp, const int pollretval);
void
svc_getreqset(fd_set * rdfds);
struct netbuf *
svc_getrpccaller(const SVCXPRT *xprt);
struct cmsgcred *
__svc_getcallercreds(const SVCXPRT *xprt);
struct pollfd svc_pollset[FD_SETSIZE];
void
svc_run(void);
bool_t
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 func

tion, while others (such as svc_run()) are called when the server is initi

ated.

Routines

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

svc_dg_enablecache() This function allocates a duplicate

request cache

for the service endpoint xprt, large

enough to
hold cache_size entries. Once en

abled, 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.

svc_exit() This function, when called by any of

the RPC

server procedure or otherwise, caus

es svc_run()
to return.

As currently implemented, 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_create(3) functions, or

using
xprt_register(). The svc_exit()

function has
global scope and ends all RPC server

activity.

fd_set 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 im

plementors do
not call 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
svc_getreqset() or any creation rou

tines.

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

svc_getargs(). This
routine returns TRUE if the results

were successfully freed, and FALSE otherwise.

svc_getargs() A function macro that decodes the

arguments of an

RPC request associated with the RPC

service
transport handle xprt. The in argu

ment is the
address where the arguments will be

placed;
inproc is the XDR routine used to

decode the
arguments. This routine returns

TRUE if decoding
succeeds, and FALSE otherwise.

svc_getreq_common() This routine is called to handle a

request on the

given file descriptor.

svc_getreq_poll() This routine is only of interest if

a service

implementor does not call svc_run(),

but instead
implements custom asynchronous event

processing.
It is called when poll(2) has deter

mined that an
RPC request has arrived on some RPC

file descriptors; pollretval is the return value

from poll(2)
and pfdp is the array of 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.

svc_getreqset() This routine is only of interest if

a service

implementor does not call svc_run(),

but instead
implements custom asynchronous event

processing.
It is called when poll(2) has deter

mined that an
RPC request has arrived on some RPC

file descriptors; rdfds is the resultant read

file descriptor
bit mask. The routine returns when

all file
descriptors associated with the val

ue of rdfds
have been serviced.

svc_getrpccaller() The approved way of getting the net

work address

of the caller of a procedure associ

ated with the
RPC service transport handle xprt.

__svc_getcallercreds() Warning: this macro is specific to

FreeBSD and

thus not portable. This macro re

turns a pointer
to a cmsgcred structure, defined in

identifying
the calling client. This only works

if the
client is calling the server over an

AF_LOCAL
socket.

struct pollfd svc_pollset[FD_SETSIZE];

svc_pollset is an array of 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 svc_run().

Service
implementors who do not call

svc_run() and who
wish to use this array must perform

this derivation themselves.

svc_run() This routine never returns. It

waits for RPC

requests to arrive, and calls the

appropriate
service procedure using

svc_getreq_poll() when
one arrives. This procedure is usu

ally waiting
for the poll(2) system call to re

turn.

svc_sendreply() Called by an RPC service's dispatch

routine to

send the results of a remote proce

dure call. The
xprt argument is the request's asso

ciated transport handle; outproc is the XDR rou

tine which is
used to encode the results; and out

is the
address of the results. This rou

tine returns
TRUE if it succeeds, FALSE other

wise.

SEE ALSO

poll(2), select(2), rpc(3), rpc_svc_create(3),

rpc_svc_err(3),
rpc_svc_reg(3)

BSD May 3, 1993

BSD