1 // : vi ts=4 sw=4 noet :
3 ==================================================================================
4 Copyright (c) 2019 Nokia
5 Copyright (c) 2018-2019 AT&T Intellectual Property.
7 Licensed under the Apache License, Version 2.0 (the "License");
8 you may not use this file except in compliance with the License.
9 You may obtain a copy of the License at
11 http://www.apache.org/licenses/LICENSE-2.0
13 Unless required by applicable law or agreed to in writing, software
14 distributed under the License is distributed on an "AS IS" BASIS,
15 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 See the License for the specific language governing permissions and
17 limitations under the License.
18 ==================================================================================
23 Abstract: This is the compile point for the nng version of the rmr
24 library (formarly known as uta, so internal function names
25 are likely still uta_*)
27 With the exception of the symtab portion of the library,
28 RMr is built with a single compile so as to "hide" the
29 internal functions as statics. Because they interdepend
30 on each other, and CMake has issues with generating two
31 different wormhole objects from a single source, we just
32 pull it all together with a centralised comple using
35 Future: the API functions at this point can be separated
36 into a common source module.
38 Author: E. Scott Daniels
52 #include <arpa/inet.h>
53 #include <semaphore.h>
57 #include <nng/protocol/pubsub0/pub.h>
58 #include <nng/protocol/pubsub0/sub.h>
59 #include <nng/protocol/pipeline0/push.h>
60 #include <nng/protocol/pipeline0/pull.h>
63 #include "rmr.h" // things the users see
64 #include "rmr_agnostic.h" // agnostic things (must be included before private)
65 #include "rmr_nng_private.h" // things that we need too
66 #include "rmr_symtab.h"
68 #include "ring_static.c" // message ring support
69 #include "rt_generic_static.c" // route table things not transport specific
70 #include "rtable_nng_static.c" // route table things -- transport specific
71 #include "rtc_static.c" // route table collector
72 #include "tools_static.c"
73 #include "sr_nng_static.c" // send/receive static functions
74 #include "wormholes.c" // wormhole api externals and related static functions (must be LAST!)
75 #include "mt_call_static.c"
76 #include "mt_call_nng_static.c"
79 //------------------------------------------------------------------------------
85 static void free_ctx( uta_ctx_t* ctx ) {
88 free( ctx->rtg_addr );
93 // --------------- public functions --------------------------------------------------------------------------
96 Returns the size of the payload (bytes) that the msg buffer references.
97 Len in a message is the number of bytes which were received, or should
98 be transmitted, however, it is possible that the mbuf was allocated
99 with a larger payload space than the payload length indicates; this
100 function returns the absolute maximum space that the user has available
101 in the payload. On error (bad msg buffer) -1 is returned and errno should
104 extern int rmr_payload_size( rmr_mbuf_t* msg ) {
105 if( msg == NULL || msg->header == NULL ) {
111 return msg->alloc_len - RMR_HDR_LEN( msg->header ); // allocated transport size less the header and other data bits
115 Allocates a send message as a zerocopy message allowing the underlying message protocol
116 to send the buffer without copy.
118 extern rmr_mbuf_t* rmr_alloc_msg( void* vctx, int size ) {
122 if( (ctx = (uta_ctx_t *) vctx) == NULL ) {
126 m = alloc_zcmsg( ctx, NULL, size, 0, DEF_TR_LEN ); // alloc with default trace data
132 Allocates a send message as a zerocopy message allowing the underlying message protocol
133 to send the buffer without copy. In addition, a trace data field of tr_size will be
134 added and the supplied data coppied to the buffer before returning the message to
137 extern rmr_mbuf_t* rmr_tralloc_msg( void* vctx, int size, int tr_size, unsigned const char* data ) {
142 if( (ctx = (uta_ctx_t *) vctx) == NULL ) {
146 m = alloc_zcmsg( ctx, NULL, size, 0, tr_size ); // alloc with specific tr size
148 state = rmr_set_trace( m, data, tr_size ); // roll their data in
149 if( state != tr_size ) {
150 m->state = RMR_ERR_INITFAILED;
158 This provides an external path to the realloc static function as it's called by an
159 outward facing mbuf api function. Used to reallocate a message with a different
162 extern rmr_mbuf_t* rmr_realloc_msg( rmr_mbuf_t* msg, int new_tr_size ) {
163 return realloc_msg( msg, new_tr_size );
168 Return the message to the available pool, or free it outright.
170 extern void rmr_free_msg( rmr_mbuf_t* mbuf ) {
176 if( mbuf->flags & MFL_ZEROCOPY ) {
177 //nng_free( (void *) mbuf->header, mbuf->alloc_len );
179 nng_msg_free( mbuf->tp_buf );
188 This is a wrapper to the real timeout send. We must wrap it now to ensure that
189 the call flag and call-id are reset
191 extern rmr_mbuf_t* rmr_mtosend_msg( void* vctx, rmr_mbuf_t* msg, int max_to ) {
192 char* d1; // point at the call-id in the header
195 ((uta_mhdr_t *) msg->header)->flags &= ~HFL_CALL_MSG; // must ensure call flag is off
197 d1 = DATA1_ADDR( msg->header );
198 d1[D1_CALLID_IDX] = NO_CALL_ID; // must blot out so it doesn't queue on a chute at the other end
201 return mtosend_msg( vctx, msg, max_to );
205 Send with default max timeout as is set in the context.
206 See rmr_mtosend_msg() for more details on the parameters.
207 See rmr_stimeout() for info on setting the default timeout.
209 extern rmr_mbuf_t* rmr_send_msg( void* vctx, rmr_mbuf_t* msg ) {
210 char* d1; // point at the call-id in the header
213 ((uta_mhdr_t *) msg->header)->flags &= ~HFL_CALL_MSG; // must ensure call flag is off
215 d1 = DATA1_ADDR( msg->header );
216 d1[D1_CALLID_IDX] = NO_CALL_ID; // must blot out so it doesn't queue on a chute at the other end
219 return rmr_mtosend_msg( vctx, msg, -1 ); // retries < 0 uses default from ctx
223 Return to sender allows a message to be sent back to the endpoint where it originated.
224 The source information in the message is used to select the socket on which to write
225 the message rather than using the message type and round-robin selection. This
226 should return a message buffer with the state of the send operation set. On success
227 (state is RMR_OK, the caller may use the buffer for another receive operation), and on
228 error it can be passed back to this function to retry the send if desired. On error,
229 errno will liklely have the failure reason set by the nng send processing.
230 The following are possible values for the state in the message buffer:
232 Message states returned:
233 RMR_ERR_BADARG - argument (context or msg) was nil or invalid
234 RMR_ERR_NOHDR - message did not have a header
235 RMR_ERR_NOENDPT- an endpoint to send the message to could not be determined
236 RMR_ERR_SENDFAILED - send failed; errno has nano error code
237 RMR_ERR_RETRY - the reqest failed but should be retried (EAGAIN)
239 A nil message as the return value is rare, and generally indicates some kind of horrible
240 failure. The value of errno might give a clue as to what is wrong.
243 Like send_msg(), this is non-blocking and will return the msg if there is an errror.
244 The caller must check for this and handle.
246 extern rmr_mbuf_t* rmr_rts_msg( void* vctx, rmr_mbuf_t* msg ) {
247 nng_socket nn_sock; // endpoint socket for send
250 char* hold_src; // we need the original source if send fails
251 int sock_ok; // true if we found a valid endpoint socket
253 if( (ctx = (uta_ctx_t *) vctx) == NULL || msg == NULL ) { // bad stuff, bail fast
254 errno = EINVAL; // if msg is null, this is their clue
256 msg->state = RMR_ERR_BADARG;
261 errno = 0; // at this point any bad state is in msg returned
262 if( msg->header == NULL ) {
263 fprintf( stderr, "[ERR] rmr_send_msg: message had no header\n" );
264 msg->state = RMR_ERR_NOHDR;
268 ((uta_mhdr_t *) msg->header)->flags &= ~HFL_CALL_MSG; // must ensure call flag is off
269 sock_ok = uta_epsock_byname( ctx->rtable, (char *) ((uta_mhdr_t *)msg->header)->src, &nn_sock ); // socket of specific endpoint
271 msg->state = RMR_ERR_NOENDPT;
272 return msg; // preallocated msg can be reused since not given back to nn
275 msg->state = RMR_OK; // ensure it is clear before send
276 hold_src = strdup( (char *) ((uta_mhdr_t *)msg->header)->src ); // the dest where we're returning the message to
277 strncpy( (char *) ((uta_mhdr_t *)msg->header)->src, ctx->my_name, RMR_MAX_SID ); // must overlay the source to be ours
278 msg = send_msg( ctx, msg, nn_sock, -1 );
280 strncpy( (char *) ((uta_mhdr_t *)msg->header)->src, hold_src, RMR_MAX_SID ); // always return original source so rts can be called again
281 msg->flags |= MFL_ADDSRC; // if msg given to send() it must add source
289 If multi-threading call is turned on, this invokes that mechanism with the special call
290 id of 1 and a max wait of 1 second. If multi threaded call is not on, then the original
291 behavour (described below) is carried out. This is safe to use when mt is enabled, but
292 the user app is invoking rmr_call() from only one thread, and the caller doesn't need
295 On timeout this function will return a nil pointer. If the original message could not
296 be sent without blocking, it will be returned with the RMR_ERR_RETRY set as the status.
299 Call sends the message based on message routing using the message type, and waits for a
300 response message to arrive with the same transaction id that was in the outgoing message.
301 If, while wiating for the expected response, messages are received which do not have the
302 desired transaction ID, they are queued. Calls to uta_rcv_msg() will dequeue them in the
303 order that they were received.
305 Normally, a message struct pointer is returned and msg->state must be checked for RMR_OK
306 to ensure that no error was encountered. If the state is UTA_BADARG, then the message
307 may be resent (likely the context pointer was nil). If the message is sent, but no
308 response is received, a nil message is returned with errno set to indicate the likley
310 ETIMEDOUT -- too many messages were queued before reciving the expected response
311 ENOBUFS -- the queued message ring is full, messages were dropped
312 EINVAL -- A parameter was not valid
313 EAGAIN -- the underlying message system wsa interrupted or the device was busy;
314 user should call this function with the message again.
317 extern rmr_mbuf_t* rmr_call( void* vctx, rmr_mbuf_t* msg ) {
319 unsigned char expected_id[RMR_MAX_XID+1]; // the transaction id in the message; we wait for response with same ID
321 if( (ctx = (uta_ctx_t *) vctx) == NULL || msg == NULL ) { // bad stuff, bail fast
323 msg->state = RMR_ERR_BADARG;
328 if( ctx->flags & CFL_MTC_ENABLED ) { // if multi threaded call is on, use that
329 return rmr_mt_call( vctx, msg, 1, 1000 ); // use the reserved call-id of 1 and wait up to 1 sec
332 memcpy( expected_id, msg->xaction, RMR_MAX_XID );
333 expected_id[RMR_MAX_XID] = 0; // ensure it's a string
334 if( DEBUG > 1 ) fprintf( stderr, "[DBUG] rmr_call is making call, waiting for (%s)\n", expected_id );
336 msg->flags |= MFL_NOALLOC; // we don't need a new buffer from send
338 msg = rmr_send_msg( ctx, msg );
339 if( msg ) { // msg should be nil, if not there was a problem; return buffer to user
340 if( msg->state != RMR_ERR_RETRY ) {
341 msg->state = RMR_ERR_CALLFAILED; // errno not available to all wrappers; don't stomp if marked retry
346 return rmr_rcv_specific( ctx, NULL, (char *) expected_id, 20 ); // wait for msg allowing 20 to queue ahead
350 The outward facing receive function. When invoked it will pop the oldest message
351 from the receive ring, if any are queued, and return it. If the ring is empty
352 then the receive function is invoked to wait for the next message to arrive (blocking).
354 If old_msg is provided, it will be populated (avoiding lots of free/alloc cycles). If
355 nil, a new one will be allocated. However, the caller should NOT expect to get the same
356 struct back (if a queued message is returned the message struct will be different).
358 extern rmr_mbuf_t* rmr_rcv_msg( void* vctx, rmr_mbuf_t* old_msg ) {
360 rmr_mbuf_t* qm; // message that was queued on the ring
362 if( (ctx = (uta_ctx_t *) vctx) == NULL ) {
363 if( old_msg != NULL ) {
364 old_msg->state = RMR_ERR_BADARG;
371 if( ctx->flags & CFL_MTC_ENABLED ) { // must pop from ring with a semaphore dec first
372 return rmr_mt_rcv( ctx, old_msg, -1 );
375 qm = (rmr_mbuf_t *) uta_ring_extract( ctx->mring ); // pop if queued
378 rmr_free_msg( old_msg ); // future: push onto a free list???
384 return rcv_msg( ctx, old_msg ); // nothing queued, wait for one
388 This implements a receive with a timeout via epoll. Mostly this is for
389 wrappers as native C applications can use epoll directly and will not have
392 extern rmr_mbuf_t* rmr_torcv_msg( void* vctx, rmr_mbuf_t* old_msg, int ms_to ) {
393 struct epoll_stuff* eps; // convience pointer
395 rmr_mbuf_t* qm; // message that was queued on the ring
399 if( (ctx = (uta_ctx_t *) vctx) == NULL ) {
400 if( old_msg != NULL ) {
401 old_msg->state = RMR_ERR_BADARG;
407 if( ctx->flags & CFL_MTC_ENABLED ) { // must pop from ring with a semaphore dec first
408 return rmr_mt_rcv( ctx, old_msg, ms_to );
411 qm = (rmr_mbuf_t *) uta_ring_extract( ctx->mring ); // pop if queued
414 rmr_free_msg( old_msg ); // future: push onto a free list???
420 if( (eps = ctx->eps) == NULL ) { // set up epoll on first call
421 eps = malloc( sizeof *eps );
423 if( (eps->ep_fd = epoll_create1( 0 )) < 0 ) {
424 fprintf( stderr, "[FAIL] unable to create epoll fd: %d\n", errno );
429 eps->nng_fd = rmr_get_rcvfd( ctx );
430 eps->epe.events = EPOLLIN;
431 eps->epe.data.fd = eps->nng_fd;
433 if( epoll_ctl( eps->ep_fd, EPOLL_CTL_ADD, eps->nng_fd, &eps->epe ) != 0 ) {
434 fprintf( stderr, "[FAIL] epoll_ctl status not 0 : %s\n", strerror( errno ) );
445 msg = alloc_zcmsg( ctx, NULL, RMR_MAX_RCV_BYTES, RMR_OK, DEF_TR_LEN ); // will abort on failure, no need to check
452 nready = epoll_wait( eps->ep_fd, eps->events, 1, ms_to ); // block until something or timedout
453 if( nready <= 0 ) { // we only wait on ours, so we assume ready means it's ours
454 msg->state = RMR_ERR_TIMEOUT;
456 return rcv_msg( ctx, msg ); // receive it and return it
459 return msg; // return empty message with state set
463 This blocks until the message with the 'expect' ID is received. Messages which are received
464 before the expected message are queued onto the message ring. The function will return
465 a nil message and set errno to ETIMEDOUT if allow2queue messages are received before the
466 expected message is received. If the queued message ring fills a nil pointer is returned
467 and errno is set to ENOBUFS.
469 Generally this will be invoked only by the call() function as it waits for a response, but
470 it is exposed to the user application as three is no reason not to.
472 extern rmr_mbuf_t* rmr_rcv_specific( void* vctx, rmr_mbuf_t* msg, char* expect, int allow2queue ) {
474 int queued = 0; // number we pushed into the ring
475 int exp_len = 0; // length of expected ID
477 if( (ctx = (uta_ctx_t *) vctx) == NULL ) {
479 msg->state = RMR_ERR_BADARG;
487 if( expect == NULL || ! *expect ) { // nothing expected if nil or empty string, just receive
488 return rmr_rcv_msg( ctx, msg );
491 exp_len = strlen( expect );
492 if( exp_len > RMR_MAX_XID ) {
493 exp_len = RMR_MAX_XID;
495 if( DEBUG ) fprintf( stderr, "[DBUG] rcv_specific waiting for id=%s\n", expect );
497 while( queued < allow2queue ) {
498 msg = rcv_msg( ctx, msg ); // hard wait for next
499 if( msg->state == RMR_OK ) {
500 if( memcmp( msg->xaction, expect, exp_len ) == 0 ) { // got it -- return it
501 if( DEBUG ) fprintf( stderr, "[DBUG] rcv-specific matched (%s); %d messages were queued\n", msg->xaction, queued );
505 if( ! uta_ring_insert( ctx->mring, msg ) ) { // just queue, error if ring is full
506 if( DEBUG > 1 ) fprintf( stderr, "[DBUG] rcv_specific ring is full\n" );
511 if( DEBUG ) fprintf( stderr, "[DBUG] rcv_specific queued message type=%d\n", msg->mtype );
517 if( DEBUG ) fprintf( stderr, "[DBUG] rcv_specific timeout waiting for %s\n", expect );
522 // CAUTION: these are not supported as they must be set differently (between create and open) in NNG.
523 // until those details are worked out, these generate a warning.
525 Set send timeout. The value time is assumed to be microseconds. The timeout is the
526 rough maximum amount of time that RMr will block on a send attempt when the underlying
527 mechnism indicates eagain or etimeedout. All other error conditions are reported
528 without this delay. Setting a timeout of 0 causes no retries to be attempted in
529 RMr code. Setting a timeout of 1 causes RMr to spin up to 10K retries before returning,
530 but without issuing a sleep. If timeout is > 1, then RMr will issue a sleep (1us)
531 after every 10K send attempts until the time value is reached. Retries are abandoned
532 if NNG returns anything other than NNG_AGAIN or NNG_TIMEDOUT.
534 The default, if this function is not used, is 1; meaning that RMr will retry, but will
535 not enter a sleep. In all cases the caller should check the status in the message returned
538 Returns -1 if the context was invalid; RMR_OK otherwise.
540 extern int rmr_set_stimeout( void* vctx, int time ) {
543 if( (ctx = (uta_ctx_t *) vctx) == NULL ) {
551 ctx->send_retries = time;
556 Set receive timeout -- not supported in nng implementation
558 extern int rmr_set_rtimeout( void* vctx, int time ) {
559 fprintf( stderr, "[WRN] Current implementation of RMR ontop of NNG does not support setting a receive timeout\n" );
565 This is the actual init workhorse. The user visible function meerly ensures that the
566 calling programme does NOT set any internal flags that are supported, and then
567 invokes this. Internal functions (the route table collector) which need additional
568 open ports without starting additional route table collectors, will invoke this
569 directly with the proper flag.
571 static void* init( char* uproto_port, int max_msg_size, int flags ) {
572 static int announced = 0;
573 uta_ctx_t* ctx = NULL;
574 char bind_info[NNG_MAXADDRLEN]; // bind info
575 char* proto = "tcp"; // pointer into the proto/port string user supplied
577 char* interface = NULL; // interface to bind to (from RMR_BIND_IF, 0.0.0.0 if not defined)
579 char wbuf[1024]; // work buffer
580 char* tok; // pointer at token in a buffer
584 fprintf( stderr, "[INFO] ric message routing library on NNG mv=%d (%s %s.%s.%s built: %s)\n",
585 RMR_MSG_VER, QUOTE_DEF(GIT_ID), QUOTE_DEF(MAJOR_VER), QUOTE_DEF(MINOR_VER), QUOTE_DEF(PATCH_VER), __DATE__ );
590 if( uproto_port == NULL ) {
591 proto_port = strdup( DEF_COMM_PORT );
593 proto_port = strdup( uproto_port ); // so we can modify it
596 if( (ctx = (uta_ctx_t *) malloc( sizeof( uta_ctx_t ) )) == NULL ) {
600 memset( ctx, 0, sizeof( uta_ctx_t ) );
602 ctx->send_retries = 1; // default is not to sleep at all; RMr will retry about 10K times before returning
603 ctx->d1_len = 4; // data1 space in header -- 4 bytes for now
605 if( flags & RMRFL_MTCALL ) { // mt call support is on, need bigger ring
606 ctx->mring = uta_mk_ring( 2048 ); // message ring filled by rcv thread
607 init_mtcall( ctx ); // set up call chutes
609 ctx->mring = uta_mk_ring( 128 ); // ring filled only on blocking call
612 ctx->max_plen = RMR_MAX_RCV_BYTES; // max user payload lengh
613 if( max_msg_size > 0 ) {
614 ctx->max_plen = max_msg_size;
617 // we're using a listener to get rtg updates, so we do NOT need this.
618 //uta_lookup_rtg( ctx ); // attempt to fill in rtg info; rtc will handle missing values/errors
620 if( nng_pull0_open( &ctx->nn_sock ) != 0 ) { // and assign the mode
621 fprintf( stderr, "[CRI] rmr_init: unable to initialise nng listen (pull) socket: %d\n", errno );
626 if( (port = strchr( proto_port, ':' )) != NULL ) {
627 if( port == proto_port ) { // ":1234" supplied; leave proto to default and point port correctly
630 *(port++) = 0; // term proto string and point at port string
631 proto = proto_port; // user supplied proto so point at it rather than default
634 port = proto_port; // assume something like "1234" was passed
637 if( (gethostname( wbuf, sizeof( wbuf ) )) != 0 ) {
638 fprintf( stderr, "[CRI] rmr_init: cannot determine localhost name: %s\n", strerror( errno ) );
641 if( (tok = strchr( wbuf, '.' )) != NULL ) {
642 *tok = 0; // we don't keep domain portion
644 ctx->my_name = (char *) malloc( sizeof( char ) * RMR_MAX_SID );
645 if( snprintf( ctx->my_name, RMR_MAX_SID, "%s:%s", wbuf, port ) >= RMR_MAX_SID ) { // our registered name is host:port
646 fprintf( stderr, "[CRI] rmr_init: hostname + port must be less than %d characters; %s:%s is not\n", RMR_MAX_SID, wbuf, port );
650 ctx->ip_list = mk_ip_list( port ); // suss out all IP addresses we can find on the box, and bang on our port for RT comparisons
654 if( (interface = getenv( ENV_BIND_IF )) == NULL ) {
655 interface = "0.0.0.0";
657 // NOTE: if there are options that might need to be configured, the listener must be created, options set, then started
658 // rather than using this generic listen() call.
659 snprintf( bind_info, sizeof( bind_info ), "%s://%s:%s", proto, interface, port );
660 if( (state = nng_listen( ctx->nn_sock, bind_info, NULL, NO_FLAGS )) != 0 ) {
661 fprintf( stderr, "[CRIT] rmr_init: unable to start nng listener for %s: %s\n", bind_info, nng_strerror( state ) );
662 nng_close( ctx->nn_sock );
667 if( !(flags & FL_NOTHREAD) ) { // skip if internal function that doesnt need an rtc
668 if( pthread_create( &ctx->rtc_th, NULL, rtc, (void *) ctx ) ) { // kick the rt collector thread
669 fprintf( stderr, "[WARN] rmr_init: unable to start route table collector thread: %s", strerror( errno ) );
673 if( (flags & RMRFL_MTCALL) && ! (ctx->flags & CFL_MTC_ENABLED) ) { // mt call support is on, must start the listener thread if not running
674 ctx->flags |= CFL_MTC_ENABLED;
675 if( pthread_create( &ctx->mtc_th, NULL, mt_receive, (void *) ctx ) ) { // kick the receiver
676 fprintf( stderr, "[WARN] rmr_init: unable to start multi-threaded receiver: %s", strerror( errno ) );
686 Initialise the message routing environment. Flags are one of the UTAFL_
687 constants. Proto_port is a protocol:port string (e.g. tcp:1234). If default protocol
688 (tcp) to be used, then :port is all that is needed.
690 At the moment it seems that TCP really is the only viable protocol, but
691 we'll allow flexibility.
693 The return value is a void pointer which must be passed to most uta functions. On
694 error, a nil pointer is returned and errno should be set.
697 No user flags supported (needed) at the moment, but this provides for extension
698 without drastically changing anything. The user should invoke with RMRFL_NONE to
699 avoid any misbehavour as there are internal flags which are suported
701 extern void* rmr_init( char* uproto_port, int max_msg_size, int flags ) {
702 return init( uproto_port, max_msg_size, flags & UFL_MASK ); // ensure any internal flags are off
706 This sets the default trace length which will be added to any message buffers
707 allocated. It can be set at any time, and if rmr_set_trace() is given a
708 trace len that is different than the default allcoated in a message, the message
711 Returns 0 on failure and 1 on success. If failure, then errno will be set.
713 extern int rmr_init_trace( void* vctx, int tr_len ) {
717 if( (ctx = (uta_ctx_t *) vctx) == NULL ) {
722 ctx->trace_data_len = tr_len;
727 Return true if routing table is initialised etc. and app can send/receive.
729 extern int rmr_ready( void* vctx ) {
732 if( (ctx = (uta_ctx_t *) vctx) == NULL ) {
736 if( ctx->rtable != NULL ) {
744 Returns a file descriptor which can be used with epoll() to signal a receive
745 pending. The file descriptor should NOT be read from directly, nor closed, as NNG
746 does not support this.
748 extern int rmr_get_rcvfd( void* vctx ) {
753 if( (ctx = (uta_ctx_t *) vctx) == NULL ) {
757 if( (state = nng_getopt_int( ctx->nn_sock, NNG_OPT_RECVFD, &fd )) != 0 ) {
758 fprintf( stderr, "[WRN] rmr cannot get recv fd: %s\n", nng_strerror( state ) );
769 There isn't an nng_flush() per se, but we can pause, generate
770 a context switch, which should allow the last sent buffer to
771 flow. There isn't exactly an nng_term/close either, so there
772 isn't much we can do.
774 extern void rmr_close( void* vctx ) {
777 if( (ctx = (uta_ctx_t *) vctx) == NULL ) {
782 nng_close( ctx->nn_sock );
786 // ----- multi-threaded call/receive support -------------------------------------------------
789 Blocks on the receive ring chute semaphore and then reads from the ring
790 when it is tickled. If max_wait is -1 then the function blocks until
791 a message is ready on the ring. Else max_wait is assumed to be the number
792 of millaseconds to wait before returning a timeout message.
794 extern rmr_mbuf_t* rmr_mt_rcv( void* vctx, rmr_mbuf_t* mbuf, int max_wait ) {
796 uta_mhdr_t* hdr; // header in the transport buffer
798 struct timespec ts; // time info if we have a timeout
799 long new_ms; // adjusted mu-sec
800 long seconds = 0; // max wait seconds
801 long nano_sec; // max wait xlated to nano seconds
803 rmr_mbuf_t* ombuf; // mbuf user passed; if we timeout we return state here
805 if( (ctx = (uta_ctx_t *) vctx) == NULL ) {
808 mbuf->state = RMR_ERR_BADARG;
813 if( ! (ctx->flags & CFL_MTC_ENABLED) ) {
816 mbuf->state = RMR_ERR_NOTSUPP;
823 ombuf->state = RMR_ERR_TIMEOUT; // preset if for failure
827 chute = &ctx->chutes[0]; // chute 0 used only for its semaphore
830 clock_gettime( CLOCK_REALTIME, &ts );
832 if( max_wait > 999 ) {
833 seconds = (max_wait - 999)/1000;
834 max_wait -= seconds * 1000;
835 ts.tv_sec += seconds;
838 nano_sec = max_wait * 1000000;
839 ts.tv_nsec += nano_sec;
840 if( ts.tv_nsec > 999999999 ) {
841 ts.tv_nsec -= 999999999;
846 seconds = 1; // use as flag later to invoked timed wait
850 while( chute->mbuf == NULL && ! errno ) {
852 state = sem_timedwait( &chute->barrier, &ts ); // wait for msg or timeout
854 state = sem_wait( &chute->barrier );
857 if( state < 0 && errno == EINTR ) { // interrupted go back and wait; all other errors cause exit
863 mbuf = ombuf; // return caller's buffer if they passed one in
865 if( DEBUG ) fprintf( stderr, "[DBUG] mt_rcv extracting from normal ring\n" );
866 if( (mbuf = (rmr_mbuf_t *) uta_ring_extract( ctx->mring )) != NULL ) { // pop if queued
868 mbuf->state = RMR_OK;
871 rmr_free_msg( ombuf ); // we cannot reuse as mbufs are queued on the ring
874 mbuf = ombuf; // no buffer, return user's if there
883 Accept a message buffer and caller ID, send the message and then wait
884 for the receiver to tickle the semaphore letting us know that a message
885 has been received. The call_id is a value between 2 and 255, inclusive; if
886 it's not in this range an error will be returned. Max wait is the amount
887 of time in millaseconds that the call should block for. If 0 is given
888 then no timeout is set.
890 If the mt_call feature has not been initialised, then the attempt to use this
891 funciton will fail with RMR_ERR_NOTSUPP
893 If no matching message is received before the max_wait period expires, a
894 nil pointer is returned, and errno is set to ETIMEOUT. If any other error
895 occurs after the message has been sent, then a nil pointer is returned
896 with errno set to some other value.
898 extern rmr_mbuf_t* rmr_mt_call( void* vctx, rmr_mbuf_t* mbuf, int call_id, int max_wait ) {
899 rmr_mbuf_t* ombuf; // original mbuf passed in
901 uta_mhdr_t* hdr; // header in the transport buffer
903 unsigned char* d1; // d1 data in header
904 struct timespec ts; // time info if we have a timeout
905 long new_ms; // adjusted mu-sec
906 long seconds = 0; // max wait seconds
907 long nano_sec; // max wait xlated to nano seconds
910 if( (ctx = (uta_ctx_t *) vctx) == NULL || mbuf == NULL ) {
913 mbuf->state = RMR_ERR_BADARG;
918 if( ! (ctx->flags & CFL_MTC_ENABLED) ) {
919 mbuf->state = RMR_ERR_NOTSUPP;
923 if( call_id > MAX_CALL_ID || call_id < 2 ) { // 0 and 1 are reserved; user app cannot supply them
924 mbuf->state = RMR_ERR_BADARG;
928 ombuf = mbuf; // save to return timeout status with
930 chute = &ctx->chutes[call_id];
931 if( chute->mbuf != NULL ) { // probably a delayed message that wasn't dropped
932 rmr_free_msg( chute->mbuf );
936 hdr = (uta_mhdr_t *) mbuf->header;
937 hdr->flags |= HFL_CALL_MSG; // must signal this sent with a call
938 memcpy( chute->expect, mbuf->xaction, RMR_MAX_XID ); // xaction that we will wait for
939 d1 = DATA1_ADDR( hdr );
940 d1[D1_CALLID_IDX] = (unsigned char) call_id; // set the caller ID for the response
941 mbuf->flags |= MFL_NOALLOC; // send message without allocating a new one (expect nil from mtosend
944 clock_gettime( CLOCK_REALTIME, &ts );
946 if( max_wait > 999 ) {
947 seconds = (max_wait - 999)/1000;
948 max_wait -= seconds * 1000;
949 ts.tv_sec += seconds;
952 nano_sec = max_wait * 1000000;
953 ts.tv_nsec += nano_sec;
954 if( ts.tv_nsec > 999999999 ) {
955 ts.tv_nsec -= 999999999;
960 seconds = 1; // use as flag later to invoked timed wait
963 mbuf = mtosend_msg( ctx, mbuf, 0 ); // use internal function so as not to strip call-id; should be nil on success!
965 if( mbuf->state != RMR_OK ) {
966 return mbuf; // timeout or unable to connect or no endpoint are most likely issues
971 while( chute->mbuf == NULL && ! errno ) {
973 state = sem_timedwait( &chute->barrier, &ts ); // wait for msg or timeout
975 state = sem_wait( &chute->barrier );
978 if( state < 0 && errno == EINTR ) { // interrupted go back and wait; all other errors cause exit
982 if( chute->mbuf != NULL ) { // offload receiver thread and check xaction buffer here
983 if( memcmp( chute->expect, chute->mbuf->xaction, RMR_MAX_XID ) != 0 ) {
984 rmr_free_msg( chute->mbuf );
992 return NULL; // leave errno as set by sem wait call
996 mbuf->state = RMR_OK;