1rpc_svc_calls(3NSL) Networking Services Library Functions rpc_svc_calls(3NSL)
2
6 rpc_svc_calls, svc_dg_enablecache, svc_done, svc_exit, svc_fdset,
7 svc_freeargs, svc_getargs, svc_getreq_common, svc_getreq_poll,
8 svc_getreqset, svc_getrpccaller, svc_max_pollfd, svc_pollfd, svc_run,
9 svc_sendreply, svc_getcallerucred, svc_fd_negotiate_ucred - library
10 routines for RPC servers
11
13 cc [ flag... ] file... -lnsl [ library...]
14 #include <rpc/rpc.h>
15 int svc_dg_enablecache(SVCXPRT *xprt, const uint_t cache_size);
17 int svc_done(SVCXPRT *xprt);
20 void svc_exit(void);
23 void svc_fd_negotiate_ucred(int fd);
26 bool_t svc_freeargs(const SVCXPRT *xprt, const txdrproc_t inproc,
29 caddr_t in);
30 bool_t svc_getargs(const SVCXPRT *xprt, const xdrproc_t inproc,
33 caddr_t in);
34 int svc_getcallerucred(const SVCXPRT *xprt, ucred_t **ucred);
37 void svc_getreq_common(const int fd);
40 void svc_getreqset(fd_set *rdfds);
43 void svc_getreq_poll(struct pollfd *pfdp, const int pollretval);
46 struct netbuf *svc_getrpccaller(const SVCXPRT *xprt);
49 void svc_run(void);
52 bool_t svc_sendreply(const SVCXPRT *xprt, const xdrproc_t outproc,
55 caddr_t outint svc_max_pollfd;
56 fd_set svc_fdset;
57 pollfd_t *svc_pollfd;
58
61 These routines are part of the RPC library which allows C language pro‐
62 grams to make procedure calls on other machines across the network.
63 These routines are associated with the server side of the RPC mecha‐
66 nism. Some of them are called by the server side dispatch function.
67 Others, such as svc_run(), are called when the server is initiated.
68 Because the service transport handle SVCXPRT contains a single data
71 area for decoding arguments and encoding results, the structure cannot
72 freely be shared between threads that call functions to decode argu‐
73 ments and encode results. When a server is operating in the Automatic
74 or User MT modes, however, a copy of this structure is passed to the
75 service dispatch procedure in order to enable concurrent request pro‐
76 cessing. Under these circumstances, some routines which would otherwise
77 be Unsafe, become Safe. These are marked as such. Also marked are rou‐
78 tines that are Unsafe for multithreaded applications, and are not to be
79 used by such applications. See rpc(3NSL) for the definition of the
80 SVCXPRT data structure.
81 The svc_dg_enablecache() function allocates a duplicate request cache
84 for the service endpoint xprt, large enough to hold cache_size entries.
85 Once enabled, there is no way to disable caching. The function returns
86 1 if space necessary for a cache of the given size was successfully
87 allocated, and 0 otherwise. This function is Safe in multithreaded
88 applications.
89 The svc_done() function frees resources allocated to service a client
92 request directed to the service endpoint xprt. This call pertains only
93 to servers executing in the User MT mode. In the User MT mode, service
94 procedures must invoke this call before returning, either after a
95 client request has been serviced, or after an error or abnormal condi‐
96 tion that prevents a reply from being sent. After svc_done() is
97 invoked, the service endpoint xprt should not be referenced by the ser‐
98 vice procedure. Server multithreading modes and parameters can be set
99 using the rpc_control() call. This function is Safe in multithreaded
100 applications. It will have no effect if invoked in modes other than the
101 User MT mode.
102 The svc_exit() function when called by any of the RPC server procedures
105 or otherwise, destroys all services registered by the server and causes
106 svc_run() to return. If RPC server activity is to be resumed, services
107 must be reregistered with the RPC library either through one of the
108 rpc_svc_create(3NSL) functions, or using xprt_register(3NSL). The
109 svc_exit() function has global scope and ends all RPC server activity.
110 The svc_freeargs() function macro frees any data allocated by the
113 RPC/XDR system when it decoded the arguments to a service procedure
114 using svc_getargs(). This routine returns TRUE if the results were suc‐
115 cessfully freed, and FALSE otherwise. This function macro is Safe in
116 multithreaded applications utilizing the Automatic or User MT modes.
117 The svc_getargs() function macro decodes the arguments of an RPC
120 request associated with the RPC service transport handle xprt. The
121 parameter in is the address where the arguments will be placed; inproc
122 is the XDR routine used to decode the arguments. This routine returns
123 TRUE if decoding succeeds, and FALSE otherwise. This function macro is
124 Safe in multithreaded applications utilizing the Automatic or User MT
125 modes.
126 The svc_getreq_common() function is called to handle a request on a
129 file descriptor.
130 The svc_getreq_poll() function is only of interest if a service imple‐
133 mentor does not call svc_run(), but instead implements custom asynchro‐
134 nous event processing. It is called when poll(2) has determined that an
135 RPC request has arrived on some RPC file descriptors; pollretval is the
136 return value from poll(2) and pfdp is the array of pollfd structures on
137 which the poll(2) was done. It is assumed to be an array large enough
138 to contain the maximal number of descriptors allowed. The
139 svc_getreq_poll() function macro is Unsafe in multithreaded applica‐
140 tions.
141 The svc_getreqset() function is only of interest if a service implemen‐
144 tor does not call svc_run(), but instead implements custom asynchronous
145 event processing. It is called when select(3C) has determined that an
146 RPC request has arrived on some RPC file descriptors; rdfds is the
147 resultant read file descriptor bit mask. The routine returns when all
148 file descriptors associated with the value of rdfds have been serviced.
149 This function macro is Unsafe in multithreaded applications.
150 The svc_getrpccaller() function is the approved way of getting the net‐
153 work address of the caller of a procedure associated with the RPC ser‐
154 vice transport handle xprt. This function macro is Safe in multi‐
155 threaded applications.
156 The svc_run() function never returns. In single-threaded mode, the
159 function waits for RPC requests to arrive. When an RPC request arrives,
160 the svc_run() function calls the appropriate service procedure. This
161 procedure is usually waiting for the poll(2) library call to return.
162 Applications that execute in the Automatic or the User MT mode should
165 invoke the svc_run() function exactly once. In the Automatic MT mode,
166 the svc_run() function creates threads to service client requests. In
167 the User MT mode, the function provides a framework for service devel‐
168 opers to create and manage their own threads for servicing client
169 requests.
170 The svc_fdset global variable reflects the RPC server's read file
173 descriptor bit mask. This is only of interest if service implementors
174 do not call svc_run(), but rather do their own asynchronous event pro‐
175 cessing. This variable is read-only may change after calls to
176 svc_getreqset() or after any creation routine. Do not pass its address
177 to select(3C). Instead, pass the address of a copy. multithreaded
178 applications executing in either the Automatic MT mode or the user MT
179 mode should never read this variable. They should use auxiliary threads
180 to do asynchronous event processing. The svc_fdset variable is limited
181 to 1024 file descriptors and is considered obsolete. Use of svc_pollfd
182 is recommended instead.
183 The svc_pollfd global variable points to an array of pollfd_t struc‐
186 tures that reflect the RPC server's read file descriptor array. This is
187 only of interest if service service implementors do not call svc_run()
188 but rather do their own asynchronous event processing. This variable is
189 read-only, and it may change after calls to svc_getreg_poll() or any
190 creation routines. Do no pass its address to poll(2). Instead, pass the
191 address of a copy. By default, svc_pollfd is limited to 1024 entries.
192 Use rpc_control(3NSL) to remove this limitation. multithreaded applica‐
193 tions executing in either the Automatic MT mode or the user MT mode
194 should never be read this variable. They should use auxiliary threads
195 to do asynchronous event processing.
196 The svc_max_pollfd global variable contains the maximum length of the
199 svc_pollfd array. This variable is read-only, and it may change after
200 calls to svc_getreg_poll() or any creation routines.
201 The svc_sendreply() function is called by an RPC service dispatch rou‐
204 tine to send the results of a remote procedure call. The xprt parameter
205 is the transport handle of the request. The outproc parameter is the
206 XDR routine used to encode the results. The out parameter is the
207 address of the results. This routine returns TRUE if it succeeds, FALSE
208 otherwise. The svc_sendreply() function macro is Safe in multithreaded
209 applications that use the Automatic or the User MT mode.
210 The svc_fd_negotiate_ucred() function is called by an RPC server to
213 inform the underlying transport that the function wishes to receive
214 ucreds for local calls, including those over IP transports.
215 The svc_getcallerucred() function attempts to retrieve the ucred_t
218 associated with the caller. The function returns 0 when successful and
219 -1 when not.
220 When successful, the svc_getcallerucred() function stores the pointer
223 to a freshly allocated ucred_t in the memory location pointed to by the
224 ucred argument if that memory location contains the null pointer. If
225 the memory location is non-null, the function reuses the existing
226 ucred_t. When ucred is no longer needed, a credential allocated by
227 svc_getcallerucred() should be freed with ucred_free(3C).
228
230 See attributes(5) for descriptions of attribute types and values.
231 ┌─────────────────────────────┬─────────────────────────────┐
236 │ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
237 ├─────────────────────────────┼─────────────────────────────┤
238 │MT-Level │See below. │
239 └─────────────────────────────┴─────────────────────────────┘
240 The svc_fd_negotiate_ucred(), svc_dg_enablecache(), svc_getrpccaller(),
243 and svc_getcallerucred() functions are Safe in multithreaded applica‐
244 tions. The svc_freeargs(), svc_getargs(), and svc_sendreply() functions
245 are Safe in multithreaded applications that use the Automatic or the
246 User MT mode. The svc_getreq_common(), svc_getreqset(), and
247 svc_getreq_poll() functions are Unsafe in multithreaded applications
248 and should be called only from the main thread.
249
251 rpcgen(1), poll(2), getpeerucred(3C), rpc(3NSL), rpc_control(3NSL),
252 rpc_svc_create(3NSL), rpc_svc_err(3NSL), rpc_svc_reg(3NSL), select(3C),
253 ucred_free(3C), xprt_register(3NSL), attributes(5)
254SunOS 5.11 26 Jan 2004 rpc_svc_calls(3NSL)