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;
257 msg->tp_state = errno;
262 errno = 0; // at this point any bad state is in msg returned
263 if( msg->header == NULL ) {
264 fprintf( stderr, "[ERR] rmr_send_msg: message had no header\n" );
265 msg->state = RMR_ERR_NOHDR;
266 msg->tp_state = errno;
270 ((uta_mhdr_t *) msg->header)->flags &= ~HFL_CALL_MSG; // must ensure call flag is off
271 if( HDR_VERSION( msg->header ) > 2 ) { // new version uses sender's ip address for rts
272 sock_ok = uta_epsock_byname( ctx->rtable, (char *) ((uta_mhdr_t *)msg->header)->srcip, &nn_sock ); // default to IP based rts
275 sock_ok = uta_epsock_byname( ctx->rtable, (char *) ((uta_mhdr_t *)msg->header)->src, &nn_sock ); // IP not in rt, try name
277 msg->state = RMR_ERR_NOENDPT;
278 return msg; // preallocated msg can be reused since not given back to nn
282 msg->state = RMR_OK; // ensure it is clear before send
283 hold_src = strdup( (char *) ((uta_mhdr_t *)msg->header)->src ); // the dest where we're returning the message to
284 strncpy( (char *) ((uta_mhdr_t *)msg->header)->src, ctx->my_name, RMR_MAX_SRC ); // must overlay the source to be ours
285 msg = send_msg( ctx, msg, nn_sock, -1 );
287 strncpy( (char *) ((uta_mhdr_t *)msg->header)->src, hold_src, RMR_MAX_SRC ); // always return original source so rts can be called again
288 msg->flags |= MFL_ADDSRC; // if msg given to send() it must add source
296 If multi-threading call is turned on, this invokes that mechanism with the special call
297 id of 1 and a max wait of 1 second. If multi threaded call is not on, then the original
298 behavour (described below) is carried out. This is safe to use when mt is enabled, but
299 the user app is invoking rmr_call() from only one thread, and the caller doesn't need
302 On timeout this function will return a nil pointer. If the original message could not
303 be sent without blocking, it will be returned with the RMR_ERR_RETRY set as the status.
306 Call sends the message based on message routing using the message type, and waits for a
307 response message to arrive with the same transaction id that was in the outgoing message.
308 If, while wiating for the expected response, messages are received which do not have the
309 desired transaction ID, they are queued. Calls to uta_rcv_msg() will dequeue them in the
310 order that they were received.
312 Normally, a message struct pointer is returned and msg->state must be checked for RMR_OK
313 to ensure that no error was encountered. If the state is UTA_BADARG, then the message
314 may be resent (likely the context pointer was nil). If the message is sent, but no
315 response is received, a nil message is returned with errno set to indicate the likley
317 ETIMEDOUT -- too many messages were queued before reciving the expected response
318 ENOBUFS -- the queued message ring is full, messages were dropped
319 EINVAL -- A parameter was not valid
320 EAGAIN -- the underlying message system wsa interrupted or the device was busy;
321 user should call this function with the message again.
324 extern rmr_mbuf_t* rmr_call( void* vctx, rmr_mbuf_t* msg ) {
326 unsigned char expected_id[RMR_MAX_XID+1]; // the transaction id in the message; we wait for response with same ID
328 if( (ctx = (uta_ctx_t *) vctx) == NULL || msg == NULL ) { // bad stuff, bail fast
330 msg->state = RMR_ERR_BADARG;
335 if( ctx->flags & CFL_MTC_ENABLED ) { // if multi threaded call is on, use that
336 return rmr_mt_call( vctx, msg, 1, 1000 ); // use the reserved call-id of 1 and wait up to 1 sec
339 memcpy( expected_id, msg->xaction, RMR_MAX_XID );
340 expected_id[RMR_MAX_XID] = 0; // ensure it's a string
341 if( DEBUG > 1 ) fprintf( stderr, "[DBUG] rmr_call is making call, waiting for (%s)\n", expected_id );
343 msg->flags |= MFL_NOALLOC; // we don't need a new buffer from send
345 msg = rmr_send_msg( ctx, msg );
346 if( msg ) { // msg should be nil, if not there was a problem; return buffer to user
347 if( msg->state != RMR_ERR_RETRY ) {
348 msg->state = RMR_ERR_CALLFAILED; // errno not available to all wrappers; don't stomp if marked retry
350 msg->tp_state = errno;
354 return rmr_rcv_specific( ctx, NULL, (char *) expected_id, 20 ); // wait for msg allowing 20 to queue ahead
358 The outward facing receive function. When invoked it will pop the oldest message
359 from the receive ring, if any are queued, and return it. If the ring is empty
360 then the receive function is invoked to wait for the next message to arrive (blocking).
362 If old_msg is provided, it will be populated (avoiding lots of free/alloc cycles). If
363 nil, a new one will be allocated. However, the caller should NOT expect to get the same
364 struct back (if a queued message is returned the message struct will be different).
366 extern rmr_mbuf_t* rmr_rcv_msg( void* vctx, rmr_mbuf_t* old_msg ) {
368 rmr_mbuf_t* qm; // message that was queued on the ring
370 if( (ctx = (uta_ctx_t *) vctx) == NULL ) {
372 if( old_msg != NULL ) {
373 old_msg->state = RMR_ERR_BADARG;
374 old_msg->tp_state = errno;
380 if( ctx->flags & CFL_MTC_ENABLED ) { // must pop from ring with a semaphore dec first
381 return rmr_mt_rcv( ctx, old_msg, -1 );
384 qm = (rmr_mbuf_t *) uta_ring_extract( ctx->mring ); // pop if queued
387 rmr_free_msg( old_msg ); // future: push onto a free list???
393 return rcv_msg( ctx, old_msg ); // nothing queued, wait for one
397 This implements a receive with a timeout via epoll. Mostly this is for
398 wrappers as native C applications can use epoll directly and will not have
401 extern rmr_mbuf_t* rmr_torcv_msg( void* vctx, rmr_mbuf_t* old_msg, int ms_to ) {
402 struct epoll_stuff* eps; // convience pointer
404 rmr_mbuf_t* qm; // message that was queued on the ring
408 if( (ctx = (uta_ctx_t *) vctx) == NULL ) {
410 if( old_msg != NULL ) {
411 old_msg->state = RMR_ERR_BADARG;
412 old_msg->tp_state = errno;
417 if( ctx->flags & CFL_MTC_ENABLED ) { // must pop from ring with a semaphore dec first
418 return rmr_mt_rcv( ctx, old_msg, ms_to );
421 qm = (rmr_mbuf_t *) uta_ring_extract( ctx->mring ); // pop if queued
424 rmr_free_msg( old_msg ); // future: push onto a free list???
430 if( (eps = ctx->eps) == NULL ) { // set up epoll on first call
431 eps = malloc( sizeof *eps );
433 if( (eps->ep_fd = epoll_create1( 0 )) < 0 ) {
434 fprintf( stderr, "[FAIL] unable to create epoll fd: %d\n", errno );
439 eps->nng_fd = rmr_get_rcvfd( ctx );
440 eps->epe.events = EPOLLIN;
441 eps->epe.data.fd = eps->nng_fd;
443 if( epoll_ctl( eps->ep_fd, EPOLL_CTL_ADD, eps->nng_fd, &eps->epe ) != 0 ) {
444 fprintf( stderr, "[FAIL] epoll_ctl status not 0 : %s\n", strerror( errno ) );
455 msg = alloc_zcmsg( ctx, NULL, RMR_MAX_RCV_BYTES, RMR_OK, DEF_TR_LEN ); // will abort on failure, no need to check
462 nready = epoll_wait( eps->ep_fd, eps->events, 1, ms_to ); // block until something or timedout
463 if( nready <= 0 ) { // we only wait on ours, so we assume ready means it's ours
464 msg->state = RMR_ERR_TIMEOUT;
465 msg->tp_state = errno;
467 return rcv_msg( ctx, msg ); // receive it and return it
470 return msg; // return empty message with state set
474 This blocks until the message with the 'expect' ID is received. Messages which are received
475 before the expected message are queued onto the message ring. The function will return
476 a nil message and set errno to ETIMEDOUT if allow2queue messages are received before the
477 expected message is received. If the queued message ring fills a nil pointer is returned
478 and errno is set to ENOBUFS.
480 Generally this will be invoked only by the call() function as it waits for a response, but
481 it is exposed to the user application as three is no reason not to.
483 extern rmr_mbuf_t* rmr_rcv_specific( void* vctx, rmr_mbuf_t* msg, char* expect, int allow2queue ) {
485 int queued = 0; // number we pushed into the ring
486 int exp_len = 0; // length of expected ID
488 if( (ctx = (uta_ctx_t *) vctx) == NULL ) {
491 msg->state = RMR_ERR_BADARG;
492 msg->tp_state = errno;
499 if( expect == NULL || ! *expect ) { // nothing expected if nil or empty string, just receive
500 return rmr_rcv_msg( ctx, msg );
503 exp_len = strlen( expect );
504 if( exp_len > RMR_MAX_XID ) {
505 exp_len = RMR_MAX_XID;
507 if( DEBUG ) fprintf( stderr, "[DBUG] rcv_specific waiting for id=%s\n", expect );
509 while( queued < allow2queue ) {
510 msg = rcv_msg( ctx, msg ); // hard wait for next
511 if( msg->state == RMR_OK ) {
512 if( memcmp( msg->xaction, expect, exp_len ) == 0 ) { // got it -- return it
513 if( DEBUG ) fprintf( stderr, "[DBUG] rcv-specific matched (%s); %d messages were queued\n", msg->xaction, queued );
517 if( ! uta_ring_insert( ctx->mring, msg ) ) { // just queue, error if ring is full
518 if( DEBUG > 1 ) fprintf( stderr, "[DBUG] rcv_specific ring is full\n" );
523 if( DEBUG ) fprintf( stderr, "[DBUG] rcv_specific queued message type=%d\n", msg->mtype );
529 if( DEBUG ) fprintf( stderr, "[DBUG] rcv_specific timeout waiting for %s\n", expect );
535 Set send timeout. The value time is assumed to be milliseconds. The timeout is the
536 _rough_ maximum amount of time that RMr will block on a send attempt when the underlying
537 mechnism indicates eagain or etimeedout. All other error conditions are reported
538 without this delay. Setting a timeout of 0 causes no retries to be attempted in
539 RMr code. Setting a timeout of 1 causes RMr to spin up to 1K retries before returning,
540 but _without_ issuing a sleep. If timeout is > 1, then RMr will issue a sleep (1us)
541 after every 1K send attempts until the "time" value is reached. Retries are abandoned
542 if NNG returns anything other than NNG_EAGAIN or NNG_ETIMEDOUT.
544 The default, if this function is not used, is 1; meaning that RMr will retry, but will
545 not enter a sleep. In all cases the caller should check the status in the message returned
548 Returns -1 if the context was invalid; RMR_OK otherwise.
550 extern int rmr_set_stimeout( void* vctx, int time ) {
553 if( (ctx = (uta_ctx_t *) vctx) == NULL ) {
561 ctx->send_retries = time;
566 Set receive timeout -- not supported in nng implementation
568 CAUTION: this is not supported as they must be set differently (between create and open) in NNG.
570 extern int rmr_set_rtimeout( void* vctx, int time ) {
571 fprintf( stderr, "[WRN] Current implementation of RMR ontop of NNG does not support setting a receive timeout\n" );
577 This is the actual init workhorse. The user visible function meerly ensures that the
578 calling programme does NOT set any internal flags that are supported, and then
579 invokes this. Internal functions (the route table collector) which need additional
580 open ports without starting additional route table collectors, will invoke this
581 directly with the proper flag.
583 static void* init( char* uproto_port, int max_msg_size, int flags ) {
584 static int announced = 0;
585 uta_ctx_t* ctx = NULL;
586 char bind_info[NNG_MAXADDRLEN]; // bind info
587 char* proto = "tcp"; // pointer into the proto/port string user supplied
589 char* interface = NULL; // interface to bind to (from RMR_BIND_IF, 0.0.0.0 if not defined)
591 char wbuf[1024]; // work buffer
592 char* tok; // pointer at token in a buffer
596 fprintf( stderr, "[INFO] ric message routing library on NNG mv=%d (%s %s.%s.%s built: %s)\n",
597 RMR_MSG_VER, QUOTE_DEF(GIT_ID), QUOTE_DEF(MAJOR_VER), QUOTE_DEF(MINOR_VER), QUOTE_DEF(PATCH_VER), __DATE__ );
602 if( uproto_port == NULL ) {
603 proto_port = strdup( DEF_COMM_PORT );
605 proto_port = strdup( uproto_port ); // so we can modify it
608 if( (ctx = (uta_ctx_t *) malloc( sizeof( uta_ctx_t ) )) == NULL ) {
612 memset( ctx, 0, sizeof( uta_ctx_t ) );
614 ctx->send_retries = 1; // default is not to sleep at all; RMr will retry about 10K times before returning
615 ctx->d1_len = 4; // data1 space in header -- 4 bytes for now
617 if( flags & RMRFL_MTCALL ) { // mt call support is on, need bigger ring
618 ctx->mring = uta_mk_ring( 2048 ); // message ring filled by rcv thread
619 init_mtcall( ctx ); // set up call chutes
621 ctx->mring = uta_mk_ring( 128 ); // ring filled only on blocking call
624 ctx->max_plen = RMR_MAX_RCV_BYTES; // max user payload lengh
625 if( max_msg_size > 0 ) {
626 ctx->max_plen = max_msg_size;
629 // we're using a listener to get rtg updates, so we do NOT need this.
630 //uta_lookup_rtg( ctx ); // attempt to fill in rtg info; rtc will handle missing values/errors
632 if( nng_pull0_open( &ctx->nn_sock ) != 0 ) { // and assign the mode
633 fprintf( stderr, "[CRI] rmr_init: unable to initialise nng listen (pull) socket: %d\n", errno );
638 if( (port = strchr( proto_port, ':' )) != NULL ) {
639 if( port == proto_port ) { // ":1234" supplied; leave proto to default and point port correctly
642 *(port++) = 0; // term proto string and point at port string
643 proto = proto_port; // user supplied proto so point at it rather than default
646 port = proto_port; // assume something like "1234" was passed
649 if( (gethostname( wbuf, sizeof( wbuf ) )) != 0 ) {
650 fprintf( stderr, "[CRI] rmr_init: cannot determine localhost name: %s\n", strerror( errno ) );
653 if( (tok = strchr( wbuf, '.' )) != NULL ) {
654 *tok = 0; // we don't keep domain portion
656 ctx->my_name = (char *) malloc( sizeof( char ) * RMR_MAX_SRC );
657 if( snprintf( ctx->my_name, RMR_MAX_SRC, "%s:%s", wbuf, port ) >= RMR_MAX_SRC ) { // our registered name is host:port
658 fprintf( stderr, "[CRI] rmr_init: hostname + port must be less than %d characters; %s:%s is not\n", RMR_MAX_SRC, wbuf, port );
662 if( (tok = getenv( ENV_NAME_ONLY )) != NULL ) {
663 if( atoi( tok ) > 0 ) {
664 flags |= RMRFL_NAME_ONLY; // don't allow IP addreess to go out in messages
668 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
669 if( flags & RMRFL_NAME_ONLY ) {
670 ctx->my_ip = strdup( ctx->my_name ); // user application or env var has specified that IP address is NOT sent out, use name
672 ctx->my_ip = get_default_ip( ctx->ip_list ); // and (guess) at what should be the default to put into messages as src
673 if( ctx->my_ip == NULL ) {
674 fprintf( stderr, "[WRN] rmr_init: default ip address could not be sussed out, using name\n" );
675 strcpy( ctx->my_ip, ctx->my_name ); // if we cannot suss it out, use the name rather than a nil pointer
678 if( DEBUG ) fprintf( stderr, "[DBUG] default ip address: %s\n", ctx->my_ip );
682 if( (interface = getenv( ENV_BIND_IF )) == NULL ) {
683 interface = "0.0.0.0";
685 // NOTE: if there are options that might need to be configured, the listener must be created, options set, then started
686 // rather than using this generic listen() call.
687 snprintf( bind_info, sizeof( bind_info ), "%s://%s:%s", proto, interface, port );
688 if( (state = nng_listen( ctx->nn_sock, bind_info, NULL, NO_FLAGS )) != 0 ) {
689 fprintf( stderr, "[CRI] rmr_init: unable to start nng listener for %s: %s\n", bind_info, nng_strerror( state ) );
690 nng_close( ctx->nn_sock );
695 if( !(flags & FL_NOTHREAD) ) { // skip if internal function that doesnt need an rtc
696 if( pthread_create( &ctx->rtc_th, NULL, rtc, (void *) ctx ) ) { // kick the rt collector thread
697 fprintf( stderr, "[WRN] rmr_init: unable to start route table collector thread: %s", strerror( errno ) );
701 if( (flags & RMRFL_MTCALL) && ! (ctx->flags & CFL_MTC_ENABLED) ) { // mt call support is on, must start the listener thread if not running
702 ctx->flags |= CFL_MTC_ENABLED;
703 if( pthread_create( &ctx->mtc_th, NULL, mt_receive, (void *) ctx ) ) { // kick the receiver
704 fprintf( stderr, "[WRN] rmr_init: unable to start multi-threaded receiver: %s", strerror( errno ) );
714 Initialise the message routing environment. Flags are one of the UTAFL_
715 constants. Proto_port is a protocol:port string (e.g. tcp:1234). If default protocol
716 (tcp) to be used, then :port is all that is needed.
718 At the moment it seems that TCP really is the only viable protocol, but
719 we'll allow flexibility.
721 The return value is a void pointer which must be passed to most uta functions. On
722 error, a nil pointer is returned and errno should be set.
725 No user flags supported (needed) at the moment, but this provides for extension
726 without drastically changing anything. The user should invoke with RMRFL_NONE to
727 avoid any misbehavour as there are internal flags which are suported
729 extern void* rmr_init( char* uproto_port, int max_msg_size, int flags ) {
730 return init( uproto_port, max_msg_size, flags & UFL_MASK ); // ensure any internal flags are off
734 This sets the default trace length which will be added to any message buffers
735 allocated. It can be set at any time, and if rmr_set_trace() is given a
736 trace len that is different than the default allcoated in a message, the message
739 Returns 0 on failure and 1 on success. If failure, then errno will be set.
741 extern int rmr_init_trace( void* vctx, int tr_len ) {
745 if( (ctx = (uta_ctx_t *) vctx) == NULL ) {
750 ctx->trace_data_len = tr_len;
755 Return true if routing table is initialised etc. and app can send/receive.
757 extern int rmr_ready( void* vctx ) {
760 if( (ctx = (uta_ctx_t *) vctx) == NULL ) {
764 if( ctx->rtable != NULL ) {
772 Returns a file descriptor which can be used with epoll() to signal a receive
773 pending. The file descriptor should NOT be read from directly, nor closed, as NNG
774 does not support this.
776 extern int rmr_get_rcvfd( void* vctx ) {
781 if( (ctx = (uta_ctx_t *) vctx) == NULL ) {
785 if( (state = nng_getopt_int( ctx->nn_sock, NNG_OPT_RECVFD, &fd )) != 0 ) {
786 fprintf( stderr, "[WRN] rmr cannot get recv fd: %s\n", nng_strerror( state ) );
797 There isn't an nng_flush() per se, but we can pause, generate
798 a context switch, which should allow the last sent buffer to
799 flow. There isn't exactly an nng_term/close either, so there
800 isn't much we can do.
802 extern void rmr_close( void* vctx ) {
805 if( (ctx = (uta_ctx_t *) vctx) == NULL ) {
810 nng_close( ctx->nn_sock );
814 // ----- multi-threaded call/receive support -------------------------------------------------
817 Blocks on the receive ring chute semaphore and then reads from the ring
818 when it is tickled. If max_wait is -1 then the function blocks until
819 a message is ready on the ring. Else max_wait is assumed to be the number
820 of millaseconds to wait before returning a timeout message.
822 extern rmr_mbuf_t* rmr_mt_rcv( void* vctx, rmr_mbuf_t* mbuf, int max_wait ) {
824 uta_mhdr_t* hdr; // header in the transport buffer
826 struct timespec ts; // time info if we have a timeout
827 long new_ms; // adjusted mu-sec
828 long seconds = 0; // max wait seconds
829 long nano_sec; // max wait xlated to nano seconds
831 rmr_mbuf_t* ombuf; // mbuf user passed; if we timeout we return state here
833 if( (ctx = (uta_ctx_t *) vctx) == NULL ) {
836 mbuf->state = RMR_ERR_BADARG;
837 mbuf->tp_state = errno;
842 if( ! (ctx->flags & CFL_MTC_ENABLED) ) {
845 mbuf->state = RMR_ERR_NOTSUPP;
846 mbuf->tp_state = errno;
853 ombuf->state = RMR_ERR_TIMEOUT; // preset if for failure
857 chute = &ctx->chutes[0]; // chute 0 used only for its semaphore
860 clock_gettime( CLOCK_REALTIME, &ts );
862 if( max_wait > 999 ) {
863 seconds = (max_wait - 999)/1000;
864 max_wait -= seconds * 1000;
865 ts.tv_sec += seconds;
868 nano_sec = max_wait * 1000000;
869 ts.tv_nsec += nano_sec;
870 if( ts.tv_nsec > 999999999 ) {
871 ts.tv_nsec -= 999999999;
876 seconds = 1; // use as flag later to invoked timed wait
880 while( chute->mbuf == NULL && ! errno ) {
882 state = sem_timedwait( &chute->barrier, &ts ); // wait for msg or timeout
884 state = sem_wait( &chute->barrier );
887 if( state < 0 && errno == EINTR ) { // interrupted go back and wait; all other errors cause exit
893 mbuf = ombuf; // return caller's buffer if they passed one in
895 if( DEBUG ) fprintf( stderr, "[DBUG] mt_rcv extracting from normal ring\n" );
896 if( (mbuf = (rmr_mbuf_t *) uta_ring_extract( ctx->mring )) != NULL ) { // pop if queued
898 mbuf->state = RMR_OK;
901 rmr_free_msg( ombuf ); // we cannot reuse as mbufs are queued on the ring
904 mbuf = ombuf; // no buffer, return user's if there
910 mbuf->tp_state = errno;
916 Accept a message buffer and caller ID, send the message and then wait
917 for the receiver to tickle the semaphore letting us know that a message
918 has been received. The call_id is a value between 2 and 255, inclusive; if
919 it's not in this range an error will be returned. Max wait is the amount
920 of time in millaseconds that the call should block for. If 0 is given
921 then no timeout is set.
923 If the mt_call feature has not been initialised, then the attempt to use this
924 funciton will fail with RMR_ERR_NOTSUPP
926 If no matching message is received before the max_wait period expires, a
927 nil pointer is returned, and errno is set to ETIMEOUT. If any other error
928 occurs after the message has been sent, then a nil pointer is returned
929 with errno set to some other value.
931 extern rmr_mbuf_t* rmr_mt_call( void* vctx, rmr_mbuf_t* mbuf, int call_id, int max_wait ) {
932 rmr_mbuf_t* ombuf; // original mbuf passed in
934 uta_mhdr_t* hdr; // header in the transport buffer
936 unsigned char* d1; // d1 data in header
937 struct timespec ts; // time info if we have a timeout
938 long new_ms; // adjusted mu-sec
939 long seconds = 0; // max wait seconds
940 long nano_sec; // max wait xlated to nano seconds
944 if( (ctx = (uta_ctx_t *) vctx) == NULL || mbuf == NULL ) {
946 mbuf->tp_state = errno;
947 mbuf->state = RMR_ERR_BADARG;
952 if( ! (ctx->flags & CFL_MTC_ENABLED) ) {
953 mbuf->state = RMR_ERR_NOTSUPP;
954 mbuf->tp_state = errno;
958 if( call_id > MAX_CALL_ID || call_id < 2 ) { // 0 and 1 are reserved; user app cannot supply them
959 mbuf->state = RMR_ERR_BADARG;
960 mbuf->tp_state = errno;
964 ombuf = mbuf; // save to return timeout status with
966 chute = &ctx->chutes[call_id];
967 if( chute->mbuf != NULL ) { // probably a delayed message that wasn't dropped
968 rmr_free_msg( chute->mbuf );
972 hdr = (uta_mhdr_t *) mbuf->header;
973 hdr->flags |= HFL_CALL_MSG; // must signal this sent with a call
974 memcpy( chute->expect, mbuf->xaction, RMR_MAX_XID ); // xaction that we will wait for
975 d1 = DATA1_ADDR( hdr );
976 d1[D1_CALLID_IDX] = (unsigned char) call_id; // set the caller ID for the response
977 mbuf->flags |= MFL_NOALLOC; // send message without allocating a new one (expect nil from mtosend
980 clock_gettime( CLOCK_REALTIME, &ts );
982 if( max_wait > 999 ) {
983 seconds = (max_wait - 999)/1000;
984 max_wait -= seconds * 1000;
985 ts.tv_sec += seconds;
988 nano_sec = max_wait * 1000000;
989 ts.tv_nsec += nano_sec;
990 if( ts.tv_nsec > 999999999 ) {
991 ts.tv_nsec -= 999999999;
996 seconds = 1; // use as flag later to invoked timed wait
999 mbuf = mtosend_msg( ctx, mbuf, 0 ); // use internal function so as not to strip call-id; should be nil on success!
1001 if( mbuf->state != RMR_OK ) {
1002 mbuf->tp_state = errno;
1003 return mbuf; // timeout or unable to connect or no endpoint are most likely issues
1008 while( chute->mbuf == NULL && ! errno ) {
1010 state = sem_timedwait( &chute->barrier, &ts ); // wait for msg or timeout
1012 state = sem_wait( &chute->barrier );
1015 if( state < 0 && errno == EINTR ) { // interrupted go back and wait; all other errors cause exit
1019 if( chute->mbuf != NULL ) { // offload receiver thread and check xaction buffer here
1020 if( memcmp( chute->expect, chute->mbuf->xaction, RMR_MAX_XID ) != 0 ) {
1021 rmr_free_msg( chute->mbuf );
1029 return NULL; // leave errno as set by sem wait call
1033 mbuf->state = RMR_OK;