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 = 0; // 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 if( HDR_VERSION( msg->header ) > 2 ) { // new version uses sender's ip address for rts
270 sock_ok = uta_epsock_byname( ctx->rtable, (char *) ((uta_mhdr_t *)msg->header)->srcip, &nn_sock ); // default to IP based rts
273 sock_ok = uta_epsock_byname( ctx->rtable, (char *) ((uta_mhdr_t *)msg->header)->src, &nn_sock ); // IP not in rt, try name
275 msg->state = RMR_ERR_NOENDPT;
276 return msg; // preallocated msg can be reused since not given back to nn
280 msg->state = RMR_OK; // ensure it is clear before send
281 hold_src = strdup( (char *) ((uta_mhdr_t *)msg->header)->src ); // the dest where we're returning the message to
282 strncpy( (char *) ((uta_mhdr_t *)msg->header)->src, ctx->my_name, RMR_MAX_SRC ); // must overlay the source to be ours
283 msg = send_msg( ctx, msg, nn_sock, -1 );
285 strncpy( (char *) ((uta_mhdr_t *)msg->header)->src, hold_src, RMR_MAX_SRC ); // always return original source so rts can be called again
286 msg->flags |= MFL_ADDSRC; // if msg given to send() it must add source
294 If multi-threading call is turned on, this invokes that mechanism with the special call
295 id of 1 and a max wait of 1 second. If multi threaded call is not on, then the original
296 behavour (described below) is carried out. This is safe to use when mt is enabled, but
297 the user app is invoking rmr_call() from only one thread, and the caller doesn't need
300 On timeout this function will return a nil pointer. If the original message could not
301 be sent without blocking, it will be returned with the RMR_ERR_RETRY set as the status.
304 Call sends the message based on message routing using the message type, and waits for a
305 response message to arrive with the same transaction id that was in the outgoing message.
306 If, while wiating for the expected response, messages are received which do not have the
307 desired transaction ID, they are queued. Calls to uta_rcv_msg() will dequeue them in the
308 order that they were received.
310 Normally, a message struct pointer is returned and msg->state must be checked for RMR_OK
311 to ensure that no error was encountered. If the state is UTA_BADARG, then the message
312 may be resent (likely the context pointer was nil). If the message is sent, but no
313 response is received, a nil message is returned with errno set to indicate the likley
315 ETIMEDOUT -- too many messages were queued before reciving the expected response
316 ENOBUFS -- the queued message ring is full, messages were dropped
317 EINVAL -- A parameter was not valid
318 EAGAIN -- the underlying message system wsa interrupted or the device was busy;
319 user should call this function with the message again.
322 extern rmr_mbuf_t* rmr_call( void* vctx, rmr_mbuf_t* msg ) {
324 unsigned char expected_id[RMR_MAX_XID+1]; // the transaction id in the message; we wait for response with same ID
326 if( (ctx = (uta_ctx_t *) vctx) == NULL || msg == NULL ) { // bad stuff, bail fast
328 msg->state = RMR_ERR_BADARG;
333 if( ctx->flags & CFL_MTC_ENABLED ) { // if multi threaded call is on, use that
334 return rmr_mt_call( vctx, msg, 1, 1000 ); // use the reserved call-id of 1 and wait up to 1 sec
337 memcpy( expected_id, msg->xaction, RMR_MAX_XID );
338 expected_id[RMR_MAX_XID] = 0; // ensure it's a string
339 if( DEBUG > 1 ) fprintf( stderr, "[DBUG] rmr_call is making call, waiting for (%s)\n", expected_id );
341 msg->flags |= MFL_NOALLOC; // we don't need a new buffer from send
343 msg = rmr_send_msg( ctx, msg );
344 if( msg ) { // msg should be nil, if not there was a problem; return buffer to user
345 if( msg->state != RMR_ERR_RETRY ) {
346 msg->state = RMR_ERR_CALLFAILED; // errno not available to all wrappers; don't stomp if marked retry
351 return rmr_rcv_specific( ctx, NULL, (char *) expected_id, 20 ); // wait for msg allowing 20 to queue ahead
355 The outward facing receive function. When invoked it will pop the oldest message
356 from the receive ring, if any are queued, and return it. If the ring is empty
357 then the receive function is invoked to wait for the next message to arrive (blocking).
359 If old_msg is provided, it will be populated (avoiding lots of free/alloc cycles). If
360 nil, a new one will be allocated. However, the caller should NOT expect to get the same
361 struct back (if a queued message is returned the message struct will be different).
363 extern rmr_mbuf_t* rmr_rcv_msg( void* vctx, rmr_mbuf_t* old_msg ) {
365 rmr_mbuf_t* qm; // message that was queued on the ring
367 if( (ctx = (uta_ctx_t *) vctx) == NULL ) {
368 if( old_msg != NULL ) {
369 old_msg->state = RMR_ERR_BADARG;
376 if( ctx->flags & CFL_MTC_ENABLED ) { // must pop from ring with a semaphore dec first
377 return rmr_mt_rcv( ctx, old_msg, -1 );
380 qm = (rmr_mbuf_t *) uta_ring_extract( ctx->mring ); // pop if queued
383 rmr_free_msg( old_msg ); // future: push onto a free list???
389 return rcv_msg( ctx, old_msg ); // nothing queued, wait for one
393 This implements a receive with a timeout via epoll. Mostly this is for
394 wrappers as native C applications can use epoll directly and will not have
397 extern rmr_mbuf_t* rmr_torcv_msg( void* vctx, rmr_mbuf_t* old_msg, int ms_to ) {
398 struct epoll_stuff* eps; // convience pointer
400 rmr_mbuf_t* qm; // message that was queued on the ring
404 if( (ctx = (uta_ctx_t *) vctx) == NULL ) {
405 if( old_msg != NULL ) {
406 old_msg->state = RMR_ERR_BADARG;
412 if( ctx->flags & CFL_MTC_ENABLED ) { // must pop from ring with a semaphore dec first
413 return rmr_mt_rcv( ctx, old_msg, ms_to );
416 qm = (rmr_mbuf_t *) uta_ring_extract( ctx->mring ); // pop if queued
419 rmr_free_msg( old_msg ); // future: push onto a free list???
425 if( (eps = ctx->eps) == NULL ) { // set up epoll on first call
426 eps = malloc( sizeof *eps );
428 if( (eps->ep_fd = epoll_create1( 0 )) < 0 ) {
429 fprintf( stderr, "[FAIL] unable to create epoll fd: %d\n", errno );
434 eps->nng_fd = rmr_get_rcvfd( ctx );
435 eps->epe.events = EPOLLIN;
436 eps->epe.data.fd = eps->nng_fd;
438 if( epoll_ctl( eps->ep_fd, EPOLL_CTL_ADD, eps->nng_fd, &eps->epe ) != 0 ) {
439 fprintf( stderr, "[FAIL] epoll_ctl status not 0 : %s\n", strerror( errno ) );
450 msg = alloc_zcmsg( ctx, NULL, RMR_MAX_RCV_BYTES, RMR_OK, DEF_TR_LEN ); // will abort on failure, no need to check
457 nready = epoll_wait( eps->ep_fd, eps->events, 1, ms_to ); // block until something or timedout
458 if( nready <= 0 ) { // we only wait on ours, so we assume ready means it's ours
459 msg->state = RMR_ERR_TIMEOUT;
461 return rcv_msg( ctx, msg ); // receive it and return it
464 return msg; // return empty message with state set
468 This blocks until the message with the 'expect' ID is received. Messages which are received
469 before the expected message are queued onto the message ring. The function will return
470 a nil message and set errno to ETIMEDOUT if allow2queue messages are received before the
471 expected message is received. If the queued message ring fills a nil pointer is returned
472 and errno is set to ENOBUFS.
474 Generally this will be invoked only by the call() function as it waits for a response, but
475 it is exposed to the user application as three is no reason not to.
477 extern rmr_mbuf_t* rmr_rcv_specific( void* vctx, rmr_mbuf_t* msg, char* expect, int allow2queue ) {
479 int queued = 0; // number we pushed into the ring
480 int exp_len = 0; // length of expected ID
482 if( (ctx = (uta_ctx_t *) vctx) == NULL ) {
484 msg->state = RMR_ERR_BADARG;
492 if( expect == NULL || ! *expect ) { // nothing expected if nil or empty string, just receive
493 return rmr_rcv_msg( ctx, msg );
496 exp_len = strlen( expect );
497 if( exp_len > RMR_MAX_XID ) {
498 exp_len = RMR_MAX_XID;
500 if( DEBUG ) fprintf( stderr, "[DBUG] rcv_specific waiting for id=%s\n", expect );
502 while( queued < allow2queue ) {
503 msg = rcv_msg( ctx, msg ); // hard wait for next
504 if( msg->state == RMR_OK ) {
505 if( memcmp( msg->xaction, expect, exp_len ) == 0 ) { // got it -- return it
506 if( DEBUG ) fprintf( stderr, "[DBUG] rcv-specific matched (%s); %d messages were queued\n", msg->xaction, queued );
510 if( ! uta_ring_insert( ctx->mring, msg ) ) { // just queue, error if ring is full
511 if( DEBUG > 1 ) fprintf( stderr, "[DBUG] rcv_specific ring is full\n" );
516 if( DEBUG ) fprintf( stderr, "[DBUG] rcv_specific queued message type=%d\n", msg->mtype );
522 if( DEBUG ) fprintf( stderr, "[DBUG] rcv_specific timeout waiting for %s\n", expect );
527 // CAUTION: these are not supported as they must be set differently (between create and open) in NNG.
528 // until those details are worked out, these generate a warning.
530 Set send timeout. The value time is assumed to be microseconds. The timeout is the
531 rough maximum amount of time that RMr will block on a send attempt when the underlying
532 mechnism indicates eagain or etimeedout. All other error conditions are reported
533 without this delay. Setting a timeout of 0 causes no retries to be attempted in
534 RMr code. Setting a timeout of 1 causes RMr to spin up to 10K retries before returning,
535 but without issuing a sleep. If timeout is > 1, then RMr will issue a sleep (1us)
536 after every 10K send attempts until the time value is reached. Retries are abandoned
537 if NNG returns anything other than NNG_AGAIN or NNG_TIMEDOUT.
539 The default, if this function is not used, is 1; meaning that RMr will retry, but will
540 not enter a sleep. In all cases the caller should check the status in the message returned
543 Returns -1 if the context was invalid; RMR_OK otherwise.
545 extern int rmr_set_stimeout( void* vctx, int time ) {
548 if( (ctx = (uta_ctx_t *) vctx) == NULL ) {
556 ctx->send_retries = time;
561 Set receive timeout -- not supported in nng implementation
563 extern int rmr_set_rtimeout( void* vctx, int time ) {
564 fprintf( stderr, "[WRN] Current implementation of RMR ontop of NNG does not support setting a receive timeout\n" );
570 This is the actual init workhorse. The user visible function meerly ensures that the
571 calling programme does NOT set any internal flags that are supported, and then
572 invokes this. Internal functions (the route table collector) which need additional
573 open ports without starting additional route table collectors, will invoke this
574 directly with the proper flag.
576 static void* init( char* uproto_port, int max_msg_size, int flags ) {
577 static int announced = 0;
578 uta_ctx_t* ctx = NULL;
579 char bind_info[NNG_MAXADDRLEN]; // bind info
580 char* proto = "tcp"; // pointer into the proto/port string user supplied
582 char* interface = NULL; // interface to bind to (from RMR_BIND_IF, 0.0.0.0 if not defined)
584 char wbuf[1024]; // work buffer
585 char* tok; // pointer at token in a buffer
589 fprintf( stderr, "[INFO] ric message routing library on NNG mv=%d (%s %s.%s.%s built: %s)\n",
590 RMR_MSG_VER, QUOTE_DEF(GIT_ID), QUOTE_DEF(MAJOR_VER), QUOTE_DEF(MINOR_VER), QUOTE_DEF(PATCH_VER), __DATE__ );
595 if( uproto_port == NULL ) {
596 proto_port = strdup( DEF_COMM_PORT );
598 proto_port = strdup( uproto_port ); // so we can modify it
601 if( (ctx = (uta_ctx_t *) malloc( sizeof( uta_ctx_t ) )) == NULL ) {
605 memset( ctx, 0, sizeof( uta_ctx_t ) );
607 ctx->send_retries = 1; // default is not to sleep at all; RMr will retry about 10K times before returning
608 ctx->d1_len = 4; // data1 space in header -- 4 bytes for now
610 if( flags & RMRFL_MTCALL ) { // mt call support is on, need bigger ring
611 ctx->mring = uta_mk_ring( 2048 ); // message ring filled by rcv thread
612 init_mtcall( ctx ); // set up call chutes
614 ctx->mring = uta_mk_ring( 128 ); // ring filled only on blocking call
617 ctx->max_plen = RMR_MAX_RCV_BYTES; // max user payload lengh
618 if( max_msg_size > 0 ) {
619 ctx->max_plen = max_msg_size;
622 // we're using a listener to get rtg updates, so we do NOT need this.
623 //uta_lookup_rtg( ctx ); // attempt to fill in rtg info; rtc will handle missing values/errors
625 if( nng_pull0_open( &ctx->nn_sock ) != 0 ) { // and assign the mode
626 fprintf( stderr, "[CRI] rmr_init: unable to initialise nng listen (pull) socket: %d\n", errno );
631 if( (port = strchr( proto_port, ':' )) != NULL ) {
632 if( port == proto_port ) { // ":1234" supplied; leave proto to default and point port correctly
635 *(port++) = 0; // term proto string and point at port string
636 proto = proto_port; // user supplied proto so point at it rather than default
639 port = proto_port; // assume something like "1234" was passed
642 if( (gethostname( wbuf, sizeof( wbuf ) )) != 0 ) {
643 fprintf( stderr, "[CRI] rmr_init: cannot determine localhost name: %s\n", strerror( errno ) );
646 if( (tok = strchr( wbuf, '.' )) != NULL ) {
647 *tok = 0; // we don't keep domain portion
649 ctx->my_name = (char *) malloc( sizeof( char ) * RMR_MAX_SRC );
650 if( snprintf( ctx->my_name, RMR_MAX_SRC, "%s:%s", wbuf, port ) >= RMR_MAX_SRC ) { // our registered name is host:port
651 fprintf( stderr, "[CRI] rmr_init: hostname + port must be less than %d characters; %s:%s is not\n", RMR_MAX_SRC, wbuf, port );
655 if( (tok = getenv( ENV_NAME_ONLY )) != NULL ) {
656 if( atoi( tok ) > 0 ) {
657 flags |= RMRFL_NAME_ONLY; // don't allow IP addreess to go out in messages
661 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
662 if( flags & RMRFL_NAME_ONLY ) {
663 ctx->my_ip = strdup( ctx->my_name ); // user application or env var has specified that IP address is NOT sent out, use name
665 ctx->my_ip = get_default_ip( ctx->ip_list ); // and (guess) at what should be the default to put into messages as src
666 if( ctx->my_ip == NULL ) {
667 fprintf( stderr, "[WRN] rmr_init: default ip address could not be sussed out, using name\n" );
668 strcpy( ctx->my_ip, ctx->my_name ); // if we cannot suss it out, use the name rather than a nil pointer
671 if( DEBUG ) fprintf( stderr, "[DBUG] default ip address: %s\n", ctx->my_ip );
675 if( (interface = getenv( ENV_BIND_IF )) == NULL ) {
676 interface = "0.0.0.0";
678 // NOTE: if there are options that might need to be configured, the listener must be created, options set, then started
679 // rather than using this generic listen() call.
680 snprintf( bind_info, sizeof( bind_info ), "%s://%s:%s", proto, interface, port );
681 if( (state = nng_listen( ctx->nn_sock, bind_info, NULL, NO_FLAGS )) != 0 ) {
682 fprintf( stderr, "[CRI] rmr_init: unable to start nng listener for %s: %s\n", bind_info, nng_strerror( state ) );
683 nng_close( ctx->nn_sock );
688 if( !(flags & FL_NOTHREAD) ) { // skip if internal function that doesnt need an rtc
689 if( pthread_create( &ctx->rtc_th, NULL, rtc, (void *) ctx ) ) { // kick the rt collector thread
690 fprintf( stderr, "[WRN] rmr_init: unable to start route table collector thread: %s", strerror( errno ) );
694 if( (flags & RMRFL_MTCALL) && ! (ctx->flags & CFL_MTC_ENABLED) ) { // mt call support is on, must start the listener thread if not running
695 ctx->flags |= CFL_MTC_ENABLED;
696 if( pthread_create( &ctx->mtc_th, NULL, mt_receive, (void *) ctx ) ) { // kick the receiver
697 fprintf( stderr, "[WRN] rmr_init: unable to start multi-threaded receiver: %s", strerror( errno ) );
707 Initialise the message routing environment. Flags are one of the UTAFL_
708 constants. Proto_port is a protocol:port string (e.g. tcp:1234). If default protocol
709 (tcp) to be used, then :port is all that is needed.
711 At the moment it seems that TCP really is the only viable protocol, but
712 we'll allow flexibility.
714 The return value is a void pointer which must be passed to most uta functions. On
715 error, a nil pointer is returned and errno should be set.
718 No user flags supported (needed) at the moment, but this provides for extension
719 without drastically changing anything. The user should invoke with RMRFL_NONE to
720 avoid any misbehavour as there are internal flags which are suported
722 extern void* rmr_init( char* uproto_port, int max_msg_size, int flags ) {
723 return init( uproto_port, max_msg_size, flags & UFL_MASK ); // ensure any internal flags are off
727 This sets the default trace length which will be added to any message buffers
728 allocated. It can be set at any time, and if rmr_set_trace() is given a
729 trace len that is different than the default allcoated in a message, the message
732 Returns 0 on failure and 1 on success. If failure, then errno will be set.
734 extern int rmr_init_trace( void* vctx, int tr_len ) {
738 if( (ctx = (uta_ctx_t *) vctx) == NULL ) {
743 ctx->trace_data_len = tr_len;
748 Return true if routing table is initialised etc. and app can send/receive.
750 extern int rmr_ready( void* vctx ) {
753 if( (ctx = (uta_ctx_t *) vctx) == NULL ) {
757 if( ctx->rtable != NULL ) {
765 Returns a file descriptor which can be used with epoll() to signal a receive
766 pending. The file descriptor should NOT be read from directly, nor closed, as NNG
767 does not support this.
769 extern int rmr_get_rcvfd( void* vctx ) {
774 if( (ctx = (uta_ctx_t *) vctx) == NULL ) {
778 if( (state = nng_getopt_int( ctx->nn_sock, NNG_OPT_RECVFD, &fd )) != 0 ) {
779 fprintf( stderr, "[WRN] rmr cannot get recv fd: %s\n", nng_strerror( state ) );
790 There isn't an nng_flush() per se, but we can pause, generate
791 a context switch, which should allow the last sent buffer to
792 flow. There isn't exactly an nng_term/close either, so there
793 isn't much we can do.
795 extern void rmr_close( void* vctx ) {
798 if( (ctx = (uta_ctx_t *) vctx) == NULL ) {
803 nng_close( ctx->nn_sock );
807 // ----- multi-threaded call/receive support -------------------------------------------------
810 Blocks on the receive ring chute semaphore and then reads from the ring
811 when it is tickled. If max_wait is -1 then the function blocks until
812 a message is ready on the ring. Else max_wait is assumed to be the number
813 of millaseconds to wait before returning a timeout message.
815 extern rmr_mbuf_t* rmr_mt_rcv( void* vctx, rmr_mbuf_t* mbuf, int max_wait ) {
817 uta_mhdr_t* hdr; // header in the transport buffer
819 struct timespec ts; // time info if we have a timeout
820 long new_ms; // adjusted mu-sec
821 long seconds = 0; // max wait seconds
822 long nano_sec; // max wait xlated to nano seconds
824 rmr_mbuf_t* ombuf; // mbuf user passed; if we timeout we return state here
826 if( (ctx = (uta_ctx_t *) vctx) == NULL ) {
829 mbuf->state = RMR_ERR_BADARG;
834 if( ! (ctx->flags & CFL_MTC_ENABLED) ) {
837 mbuf->state = RMR_ERR_NOTSUPP;
844 ombuf->state = RMR_ERR_TIMEOUT; // preset if for failure
848 chute = &ctx->chutes[0]; // chute 0 used only for its semaphore
851 clock_gettime( CLOCK_REALTIME, &ts );
853 if( max_wait > 999 ) {
854 seconds = (max_wait - 999)/1000;
855 max_wait -= seconds * 1000;
856 ts.tv_sec += seconds;
859 nano_sec = max_wait * 1000000;
860 ts.tv_nsec += nano_sec;
861 if( ts.tv_nsec > 999999999 ) {
862 ts.tv_nsec -= 999999999;
867 seconds = 1; // use as flag later to invoked timed wait
871 while( chute->mbuf == NULL && ! errno ) {
873 state = sem_timedwait( &chute->barrier, &ts ); // wait for msg or timeout
875 state = sem_wait( &chute->barrier );
878 if( state < 0 && errno == EINTR ) { // interrupted go back and wait; all other errors cause exit
884 mbuf = ombuf; // return caller's buffer if they passed one in
886 if( DEBUG ) fprintf( stderr, "[DBUG] mt_rcv extracting from normal ring\n" );
887 if( (mbuf = (rmr_mbuf_t *) uta_ring_extract( ctx->mring )) != NULL ) { // pop if queued
889 mbuf->state = RMR_OK;
892 rmr_free_msg( ombuf ); // we cannot reuse as mbufs are queued on the ring
895 mbuf = ombuf; // no buffer, return user's if there
904 Accept a message buffer and caller ID, send the message and then wait
905 for the receiver to tickle the semaphore letting us know that a message
906 has been received. The call_id is a value between 2 and 255, inclusive; if
907 it's not in this range an error will be returned. Max wait is the amount
908 of time in millaseconds that the call should block for. If 0 is given
909 then no timeout is set.
911 If the mt_call feature has not been initialised, then the attempt to use this
912 funciton will fail with RMR_ERR_NOTSUPP
914 If no matching message is received before the max_wait period expires, a
915 nil pointer is returned, and errno is set to ETIMEOUT. If any other error
916 occurs after the message has been sent, then a nil pointer is returned
917 with errno set to some other value.
919 extern rmr_mbuf_t* rmr_mt_call( void* vctx, rmr_mbuf_t* mbuf, int call_id, int max_wait ) {
920 rmr_mbuf_t* ombuf; // original mbuf passed in
922 uta_mhdr_t* hdr; // header in the transport buffer
924 unsigned char* d1; // d1 data in header
925 struct timespec ts; // time info if we have a timeout
926 long new_ms; // adjusted mu-sec
927 long seconds = 0; // max wait seconds
928 long nano_sec; // max wait xlated to nano seconds
931 if( (ctx = (uta_ctx_t *) vctx) == NULL || mbuf == NULL ) {
934 mbuf->state = RMR_ERR_BADARG;
939 if( ! (ctx->flags & CFL_MTC_ENABLED) ) {
940 mbuf->state = RMR_ERR_NOTSUPP;
944 if( call_id > MAX_CALL_ID || call_id < 2 ) { // 0 and 1 are reserved; user app cannot supply them
945 mbuf->state = RMR_ERR_BADARG;
949 ombuf = mbuf; // save to return timeout status with
951 chute = &ctx->chutes[call_id];
952 if( chute->mbuf != NULL ) { // probably a delayed message that wasn't dropped
953 rmr_free_msg( chute->mbuf );
957 hdr = (uta_mhdr_t *) mbuf->header;
958 hdr->flags |= HFL_CALL_MSG; // must signal this sent with a call
959 memcpy( chute->expect, mbuf->xaction, RMR_MAX_XID ); // xaction that we will wait for
960 d1 = DATA1_ADDR( hdr );
961 d1[D1_CALLID_IDX] = (unsigned char) call_id; // set the caller ID for the response
962 mbuf->flags |= MFL_NOALLOC; // send message without allocating a new one (expect nil from mtosend
965 clock_gettime( CLOCK_REALTIME, &ts );
967 if( max_wait > 999 ) {
968 seconds = (max_wait - 999)/1000;
969 max_wait -= seconds * 1000;
970 ts.tv_sec += seconds;
973 nano_sec = max_wait * 1000000;
974 ts.tv_nsec += nano_sec;
975 if( ts.tv_nsec > 999999999 ) {
976 ts.tv_nsec -= 999999999;
981 seconds = 1; // use as flag later to invoked timed wait
984 mbuf = mtosend_msg( ctx, mbuf, 0 ); // use internal function so as not to strip call-id; should be nil on success!
986 if( mbuf->state != RMR_OK ) {
987 return mbuf; // timeout or unable to connect or no endpoint are most likely issues
992 while( chute->mbuf == NULL && ! errno ) {
994 state = sem_timedwait( &chute->barrier, &ts ); // wait for msg or timeout
996 state = sem_wait( &chute->barrier );
999 if( state < 0 && errno == EINTR ) { // interrupted go back and wait; all other errors cause exit
1003 if( chute->mbuf != NULL ) { // offload receiver thread and check xaction buffer here
1004 if( memcmp( chute->expect, chute->mbuf->xaction, RMR_MAX_XID ) != 0 ) {
1005 rmr_free_msg( chute->mbuf );
1013 return NULL; // leave errno as set by sem wait call
1017 mbuf->state = RMR_OK;