1 // vim: 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 ==================================================================================
22 Mnemonic: rtable_nng_static.c
23 Abstract: Route table management functions which depend on the underlying
24 transport mechanism and thus cannot be included with the generic
25 route table functions.
27 This module is designed to be included by any module (main) needing
28 the static/private stuff.
30 Author: E. Scott Daniels
31 Date: 29 November 2018
34 #ifndef rtable_static_c
35 #define rtable_static_c
44 #include <sys/types.h>
49 // -----------------------------------------------------------------------------------------------------
52 Establish a TCP connection to the indicated target (IP address).
53 Target assumed to be address:port. The new socket is returned via the
54 user supplied pointer so that a success/fail code is returned directly.
55 Return value is 0 (false) on failure, 1 (true) on success.
57 In order to support multi-threaded user applications we must hold a lock before
58 we attempt to create a dialer and connect. NNG is thread safe, but we can
59 get things into a bad state if we allow a collision here. The lock grab
60 only happens on the intial session setup.
62 static int uta_link2( endpoint_t* ep ) {
63 static int flags = -1;
68 char conn_info[NNG_MAXADDRLEN]; // string to give to nano to make the connection
78 tok = getenv( "RMR_ASYNC_CONN" );
79 if( tok == NULL || *tok == '1' ) {
80 flags = NNG_FLAG_NONBLOCK; // start dialer asynch
86 target = ep->name; // always give name to transport so chaning dest IP does not break reconnect
87 nn_sock = &ep->nn_sock;
90 if( target == NULL || (addr = strchr( target, ':' )) == NULL ) { // bad address:port
91 fprintf( stderr, "rmr: link2: unable to create link: bad target: %s\n", target == NULL ? "<nil>" : target );
95 if( nn_sock == NULL ) {
100 pthread_mutex_lock( &ep->gate ); // grab the lock
102 pthread_mutex_unlock( &ep->gate );
107 if( nng_push0_open( nn_sock ) != 0 ) { // and assign the mode
108 pthread_mutex_unlock( &ep->gate );
109 fprintf( stderr, "[CRI] rmr: link2: unable to initialise nanomsg push socket to: %s\n", target );
113 snprintf( conn_info, sizeof( conn_info ), "tcp://%s", target );
114 if( (state = nng_dialer_create( dialer, *nn_sock, conn_info )) != 0 ) {
115 pthread_mutex_unlock( &ep->gate );
116 fprintf( stderr, "[WRN] rmr: link2: unable to create dialer for link to target: %s: %d\n", target, errno );
117 nng_close( *nn_sock );
121 nng_dialer_setopt_ms( *dialer, NNG_OPT_RECONNMAXT, 2000 ); // cap backoff on retries to reasonable amount (2s)
122 nng_dialer_setopt_ms( *dialer, NNG_OPT_RECONNMINT, 100 ); // start retry 100m after last failure with 2s cap
124 if( (state = nng_dialer_start( *dialer, flags )) != 0 ) { // can fail immediatly (unlike nanomsg)
125 pthread_mutex_unlock( &ep->gate );
126 fprintf( stderr, "[WRN] rmr: unable to create link to target: %s: %s\n", target, nng_strerror( state ) );
127 nng_close( *nn_sock );
131 if( DEBUG ) fprintf( stderr, "[INFO] rmr_link2l: dial was successful: %s\n", target );
133 ep->open = TRUE; // must set before release
134 pthread_mutex_unlock( &ep->gate );
139 This provides a protocol independent mechanism for establishing the connection to an endpoint.
140 Return is true (1) if the link was opened; false on error.
142 static int rt_link2_ep( endpoint_t* ep ) {
147 if( ep->open ) { // already open, do nothing
157 Add an endpoint to a route table entry for the group given. If the endpoint isn't in the
158 hash we add it and create the endpoint struct.
160 The caller must supply the specific route table (we assume it will be pending, but they
161 could live on the edge and update the active one, though that's not at all a good idea).
163 extern endpoint_t* uta_add_ep( route_table_t* rt, rtable_ent_t* rte, char* ep_name, int group ) {
165 rrgroup_t* rrg; // pointer at group to update
167 if( ! rte || ! rt ) {
168 fprintf( stderr, "[WRN] uda_add_ep didn't get a valid rt and/or rte pointer\n" );
172 if( rte->nrrgroups <= group ) {
173 fprintf( stderr, "[WRN] uda_add_ep group out of range: %d (max == %d)\n", group, rte->nrrgroups );
177 if( (rrg = rte->rrgroups[group]) == NULL ) {
178 if( (rrg = (rrgroup_t *) malloc( sizeof( *rrg ) )) == NULL ) {
179 fprintf( stderr, "[WRN] rmr_add_ep: malloc failed for round robin group: group=%d\n", group );
182 memset( rrg, 0, sizeof( *rrg ) );
184 if( (rrg->epts = (endpoint_t **) malloc( sizeof( endpoint_t ) * MAX_EP_GROUP )) == NULL ) {
185 fprintf( stderr, "[WRN] rmr_add_ep: malloc failed for group endpoint array: group=%d\n", group );
188 memset( rrg->epts, 0, sizeof( endpoint_t ) * MAX_EP_GROUP );
190 rte->rrgroups[group] = rrg;
192 rrg->ep_idx = 0; // next endpoint to send to
193 rrg->nused = 0; // number populated
194 rrg->nendpts = MAX_EP_GROUP; // number allocated
197 ep = rt_ensure_ep( rt, ep_name ); // get the ep and create one if not known
200 if( rrg->nused >= rrg->nendpts ) {
201 // future: reallocate
202 fprintf( stderr, "[WRN] endpoint array for mtype/group %d/%d is full!\n", rte->mtype, group );
206 rrg->epts[rrg->nused] = ep;
210 if( DEBUG > 1 ) fprintf( stderr, "[DBUG] endpoint added to mtype/group: %d/%d %s\n", rte->mtype, group, ep_name );
216 Given a name, find the nano socket needed to send to it. Returns the socket via
217 the user pointer passed in and sets the return value to true (1). If the
218 endpoint cannot be found false (0) is returned.
220 static int uta_epsock_byname( route_table_t* rt, char* ep_name, nng_socket* nn_sock, endpoint_t** uepp ) {
228 ep = rmr_sym_get( rt->hash, ep_name, 1 );
229 if( uepp != NULL ) { // caller needs endpoint too, give it back
233 if( DEBUG ) fprintf( stderr, "[DBUG] get ep by name for %s not in hash!\n", ep_name );
234 if( ! ep_name || (ep = rt_ensure_ep( rt, ep_name)) == NULL ) { // create one if not in rt (support rts without entry in our table)
239 if( ! ep->open ) { // not open -- connect now
240 if( DEBUG ) fprintf( stderr, "[DBUG] get ep by name for %s session not started... starting\n", ep_name );
241 if( ep->addr == NULL ) { // name didn't resolve before, try again
242 ep->addr = strdup( ep->name ); // use the name directly; if not IP then transport will do dns lookup
244 if( uta_link2( ep ) ) { // find entry in table and create link
247 *nn_sock = ep->nn_sock; // pass socket back to caller
249 if( DEBUG ) fprintf( stderr, "[DBUG] epsock_bn: connection state: %s %s\n", state ? "[OK]" : "[FAIL]", ep->name );
251 *nn_sock = ep->nn_sock;
259 Make a round robin selection within a round robin group for a route table
260 entry. Returns the nanomsg socket if there is a rte for the message
261 key, and group is defined. Socket is returned via pointer in the parm
264 The group is the group number to select from.
266 The user supplied (via pointer to) integer 'more' will be set if there are
267 additional groups beyond the one selected. This allows the caller to
268 to easily iterate over the group list -- more is set when the group should
269 be incremented and the function invoked again. Groups start at 0.
271 The return value is true (>0) if the socket was found and *nn_sock was updated
272 and false (0) if there is no associated socket for the msg type, group combination.
273 We return the index+1 from the round robin table on success so that we can verify
274 during test that different entries are being seleted; we cannot depend on the nng
275 socket being different as we could with nano.
277 NOTE: The round robin selection index increment might collide with other
278 threads if multiple threads are attempting to send to the same round
279 robin group; the consequences are small and avoid locking. The only side
280 effect is either sending two messages in a row to, or skipping, an endpoint.
281 Both of these, in the grand scheme of things, is minor compared to the
282 overhead of grabbing a lock on each call.
284 static int uta_epsock_rr( rtable_ent_t *rte, int group, int* more, nng_socket* nn_sock, endpoint_t** uepp ) {
285 endpoint_t* ep; // seected end point
286 int state = FALSE; // processing state
292 if( ! more ) { // eliminate cheks each time we need to use
296 if( ! nn_sock ) { // user didn't supply a pointer
307 if( group < 0 || group >= rte->nrrgroups ) {
308 //if( DEBUG ) fprintf( stderr, ">>>> group out of range: group=%d max=%d\n", group, rte->nrrgroups );
313 if( (rrg = rte->rrgroups[group]) == NULL ) {
314 //if( DEBUG ) fprintf( stderr, ">>>> rrg not found for group \n", group );
315 *more = 0; // groups are inserted contig, so nothing should be after a nil pointer
319 *more = group < rte->nrrgroups-1 ? (rte->rrgroups[group+1] != NULL): 0; // more if something in next group slot
321 switch( rrg->nused ) {
322 case 0: // nothing allocated, just punt
323 //if( DEBUG ) fprintf( stderr, ">>>> nothing allocated for the rrg\n" );
326 case 1: // exactly one, no rr to deal with
328 //if( DEBUG ) fprintf( stderr, ">>>> _rr returning socket with one choice in group \n" );
332 default: // need to pick one and adjust rr counts
334 idx = rrg->ep_idx++ % rrg->nused; // see note above
335 ep = rrg->epts[idx]; // select next endpoint
336 //if( DEBUG ) fprintf( stderr, ">>>> _rr returning socket with multiple choices in group idx=%d \n", rrg->ep_idx );
337 state = idx + 1; // unit test checks to see that we're cycling through, so must not just be TRUE
341 if( uepp != NULL ) { // caller needs refernce to endpoint too
344 if( state ) { // end point selected, open if not, get socket either way
345 if( ! ep->open ) { // not connected
346 if( ep->addr == NULL ) { // name didn't resolve before, try again
347 ep->addr = strdup( ep->name ); // use the name directly; if not IP then transport will do dns lookup
350 if( uta_link2( ep ) ) { // find entry in table and create link
352 *nn_sock = ep->nn_sock; // pass socket back to caller
356 if( DEBUG ) fprintf( stderr, "[DBUG] epsock_rr: connection attempted with %s: %s\n", ep->name, state ? "[OK]" : "[FAIL]" );
358 *nn_sock = ep->nn_sock;
366 Finds the rtable entry which matches the key. Returns a nil pointer if
367 no entry is found. If try_alternate is set, then we will attempt
368 to find the entry with a key based only on the message type.
370 static inline rtable_ent_t* uta_get_rte( route_table_t *rt, int sid, int mtype, int try_alt ) {
371 uint64_t key; // key is sub id and mtype banged together
372 rtable_ent_t* rte; // the entry we found
374 if( rt == NULL || rt->hash == NULL ) {
378 key = build_rt_key( sid, mtype ); // first try with a 'full' key
379 if( ((rte = rmr_sym_pull( rt->hash, key )) != NULL) || ! try_alt ) { // found or not allowed to try the alternate, return what we have
383 if( sid != UNSET_SUBID ) { // not found, and allowed to try alternate; and the sub_id was set
384 key = build_rt_key( UNSET_SUBID, mtype ); // rebuild key
385 rte = rmr_sym_pull( rt->hash, key ); // see what we get with this
392 Return a string of count information. E.g.:
393 <ep-name>:<port> <good> <hard-fail> <soft-fail>
395 Caller must free the string allocated if a buffer was not provided.
397 Pointer returned is to a freshly allocated string, or the user buffer
400 If the endpoint passed is a nil pointer, then we return a nil -- caller
403 static inline char* get_ep_counts( endpoint_t* ep, char* ubuf, int ubuf_len ) {
404 char* rs; // result string
414 rs = malloc( sizeof( char ) * ubuf_len );
417 snprintf( rs, ubuf_len, "%s %lld %lld %lld", ep->name, ep->scounts[EPSC_GOOD], ep->scounts[EPSC_FAIL], ep->scounts[EPSC_TRANS] );