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 ==================================================================================
22 Mnemonic: sr_nng_static.c
23 Abstract: These are static send/receive primatives which (sadly)
24 differ based on the underlying protocol (nng vs nanomsg).
25 Split from rmr_nng.c for easier wormhole support.
27 Author: E. Scott Daniels
28 Date: 13 February 2019
31 #ifndef _sr_nng_static_c
32 #define _sr_nng_static_c
35 #include <nng/protocol/pubsub0/pub.h>
36 #include <nng/protocol/pubsub0/sub.h>
37 #include <nng/protocol/pipeline0/push.h>
38 #include <nng/protocol/pipeline0/pull.h>
42 Translates the nng state passed in to one of ours that is suitable to put
43 into the message, and sets errno to something that might be useful.
44 If we don't have a specific RMr state, then we return the default (e.g.
47 static inline int xlate_nng_state( int state, int def_state ) {
55 case NNG_EAGAIN: // soft errors get retry as the RMr error
56 state = RMR_ERR_RETRY;
61 state = RMR_ERR_RETRY;
81 errno = EBADFD; // file des not in a good state for the operation
86 errno = EBADFD; // file des not in a good state for the operation
100 Alloc a new nano zero copy buffer and put into msg. If msg is nil, then we will alloc
101 a new message struct as well. Size is the size of the zc buffer to allocate (not
102 including our header). If size is 0, then the buffer allocated is the size previously
103 allocated (if msg is !nil) or the default size given at initialisation).
105 NOTE: while accurate, the nng doc implies that both the msg buffer and data buffer
106 are zero copy, however ONLY the message is zero copy. We now allocate and use
109 static rmr_mbuf_t* alloc_zcmsg( uta_ctx_t* ctx, rmr_mbuf_t* msg, int size, int state ) {
111 uta_mhdr_t* hdr; // convenience pointer
113 mlen = sizeof( uta_mhdr_t ); // figure size should we not have a msg buffer
114 mlen += (size > 0 ? size : ctx->max_plen); // add user requested size or size set during init
117 msg = (rmr_mbuf_t *) malloc( sizeof *msg );
119 fprintf( stderr, "[CRI] rmr_alloc_zc: cannot get memory for message\n" );
123 mlen = msg->alloc_len; // msg given, allocate the same size as before
126 memset( msg, 0, sizeof( *msg ) );
128 if( (state = nng_msg_alloc( (nng_msg **) &msg->tp_buf, mlen )) != 0 ) {
129 fprintf( stderr, "[CRI] rmr_alloc_zc: cannot get memory for zero copy buffer: %d\n", ENOMEM );
130 abort( ); // toss out a core file for this
133 msg->header = nng_msg_body( msg->tp_buf );
134 hdr = (uta_mhdr_t *) msg->header;
135 hdr->rmr_ver = RMR_MSG_VER; // version info should we need to recognised old style messages someday
136 msg->len = 0; // length of data in the payload
137 msg->alloc_len = mlen; // length of allocated payload
138 msg->payload = msg->header + sizeof( uta_mhdr_t ); // point past header to payload (single buffer allocation above)
139 msg->xaction = ((uta_mhdr_t *)msg->header)->xid; // point at transaction id in header area
140 msg->state = state; // fill in caller's state (likely the state of the last operation)
141 msg->flags |= MFL_ZEROCOPY; // this is a zerocopy sendable message
142 strncpy( (char *) ((uta_mhdr_t *)msg->header)->src, ctx->my_name, RMR_MAX_SID );
144 if( DEBUG > 1 ) fprintf( stderr, "[DBUG] alloc_zcmsg mlen=%ld size=%d mpl=%d flags=%02x\n", (long) mlen, size, ctx->max_plen, msg->flags );
150 Allocates only the mbuf and does NOT allocate an underlying transport buffer since
151 NNG receive must allocate that on its own.
153 static rmr_mbuf_t* alloc_mbuf( uta_ctx_t* ctx, int state ) {
155 uta_mhdr_t* hdr; // convenience pointer
158 msg = (rmr_mbuf_t *) malloc( sizeof *msg );
160 fprintf( stderr, "[CRI] rmr_alloc_zc: cannot get memory for message\n" );
164 memset( msg, 0, sizeof( *msg ) );
168 msg->len = -1; // no payload; invalid len
172 msg->state = RMR_ERR_UNSET;
179 This accepts a message with the assumption that only the tp_buf pointer is valid. It
180 sets all of the various header/payload/xaction pointers in the mbuf to the proper
181 spot in the transport layer buffer. The len in the header is assumed to be the
182 allocated len (a receive buffer that nng created);
184 The alen parm is the assumed allocated length; assumed because it's a value likely
185 to have come from nng receive and the actual alloc len might be larger, but we
186 can only assume this is the total usable space.
188 static void ref_tpbuf( rmr_mbuf_t* msg, size_t alen ) {
191 msg->header = nng_msg_body( msg->tp_buf ); // header is the start of the transport buffer
193 hdr = (uta_mhdr_t *) msg->header;
194 hdr->rmr_ver = RMR_MSG_VER; // version info should we need to recognised old style messages someday
195 msg->len = ntohl( hdr->plen ); // length sender says is in the payload (received length could be larger)
196 msg->alloc_len = alen; // length of whole tp buffer (including header)
197 msg->payload = msg->header + sizeof( uta_mhdr_t ); // point past header to payload (single buffer allocation above)
198 msg->xaction = ((uta_mhdr_t *)msg->header)->xid; // point at transaction id in header area
199 msg->flags |= MFL_ZEROCOPY; // this is a zerocopy sendable message
200 msg->mtype = ntohl( hdr->mtype ); // capture and convert from network order to local order
205 This will clone a message into a new zero copy buffer and return the cloned message.
207 static inline rmr_mbuf_t* clone_msg( rmr_mbuf_t* old_msg ) {
208 rmr_mbuf_t* nm; // new message buffer
212 nm = (rmr_mbuf_t *) malloc( sizeof *nm );
214 fprintf( stderr, "[CRI] rmr_clone: cannot get memory for message buffer\n" );
217 memset( nm, 0, sizeof( *nm ) );
219 mlen = old_msg->alloc_len; // length allocated before
220 if( (state = nng_msg_alloc( (nng_msg **) &nm->tp_buf, mlen )) != 0 ) {
221 fprintf( stderr, "[CRI] rmr_clone: cannot get memory for zero copy buffer: %d\n", ENOMEM );
225 nm->header = nng_msg_body( nm->tp_buf );
226 nm->mtype = old_msg->mtype;
227 nm->len = old_msg->len; // length of data in the payload
228 nm->alloc_len = mlen; // length of allocated payload
229 nm->payload = nm->header + sizeof( uta_mhdr_t ); // point past header to payload (single buffer allocation above)
230 nm->xaction = ((uta_mhdr_t *)nm->header)->xid; // point at transaction id in header area
231 nm->state = old_msg->state; // fill in caller's state (likely the state of the last operation)
232 nm->flags |= MFL_ZEROCOPY; // this is a zerocopy sendable message
234 memcpy( ((uta_mhdr_t *)nm->header)->src, ((uta_mhdr_t *)old_msg->header)->src, RMR_MAX_SID );
235 memcpy( nm->payload, old_msg->payload, old_msg->len );
241 This is the receive work horse used by the outer layer receive functions.
242 It waits for a message to be received on our listen socket. If old msg
243 is passed in, the we assume we can use it instead of allocating a new
244 one, else a new block of memory is allocated.
246 This allocates a zero copy message so that if the user wishes to call
247 rmr_rts_msg() the send is zero copy.
249 The nng timeout on send is at the ms level which is a tad too long for
250 our needs. So, if NNG returns eagain or timedout (we don't set one)
251 we will loop up to 5 times with a 10 microsecond delay between each
252 attempt. If at the end of this set of retries NNG is still saying
253 eagain/timeout we'll return to the caller with that set in errno.
254 Right now this is only for zero-copy buffers (they should all be zc
258 In the NNG msg world it must allocate the receive buffer rather
259 than accepting one that we allocated from their space and could
260 reuse. They have their reasons I guess. Thus, we will free
261 the old transport buffer if user passes the message in; at least
262 our mbuf will be reused.
264 static rmr_mbuf_t* rcv_msg( uta_ctx_t* ctx, rmr_mbuf_t* old_msg ) {
266 rmr_mbuf_t* msg = NULL; // msg received
268 size_t rsize; // nng needs to write back the size received... grrr
272 if( msg->tp_buf != NULL ) {
273 nng_msg_free( msg->tp_buf );
278 //msg = alloc_zcmsg( ctx, NULL, RMR_MAX_RCV_BYTES, RMR_OK ); // will abort on failure, no need to check
279 msg = alloc_mbuf( ctx, RMR_OK ); // msg without a transport buffer
286 //rsize = msg->alloc_len; // set to max, and we'll get len back here too
287 //msg->state = nng_recv( ctx->nn_sock, msg->header, &rsize, NO_FLAGS ); // total space (header + payload len) allocated
288 msg->state = nng_recvmsg( ctx->nn_sock, (nng_msg **) &msg->tp_buf, NO_FLAGS ); // blocks hard until received
289 if( (msg->state = xlate_nng_state( msg->state, RMR_ERR_RCVFAILED )) != RMR_OK ) {
293 if( msg->tp_buf == NULL ) { // if state is good this _should_ not be nil, but parninoia says check anyway
294 msg->state = RMR_ERR_EMPTY;
298 rsize = nng_msg_len( msg->tp_buf );
299 if( rsize >= sizeof( uta_mhdr_t ) ) { // we need at least a full header here
301 ref_tpbuf( msg, rsize ); // point payload, header etc to the just received tp buffer
302 hdr = (uta_mhdr_t *) msg->header;
303 msg->flags |= MFL_ADDSRC; // turn on so if user app tries to send this buffer we reset src
304 if( msg->len > (msg->alloc_len - sizeof( uta_mhdr_t )) ) { // way more than we should have had room for; error
305 msg->state = RMR_ERR_TRUNC;
308 if( DEBUG > 1 ) fprintf( stderr, "[DBUG] rcv_msg: got something: type=%d state=%d len=%d diff=%ld\n",
309 msg->mtype, msg->state, msg->len, msg->payload - (unsigned char *) msg->header );
312 msg->state = RMR_ERR_EMPTY;
319 Receives a 'raw' message from a non-RMr sender (no header expected). The returned
320 message buffer cannot be used to send, and the length information may or may
321 not be correct (it is set to the length received which might be more than the
322 bytes actually in the payload).
324 Mostly this supports the route table collector, but could be extended with an
325 API external function.
327 static void* rcv_payload( uta_ctx_t* ctx, rmr_mbuf_t* old_msg ) {
329 rmr_mbuf_t* msg = NULL; // msg received
330 size_t rsize; // nng needs to write back the size received... grrr
335 msg = alloc_zcmsg( ctx, NULL, RMR_MAX_RCV_BYTES, RMR_OK ); // will abort on failure, no need to check
338 msg->state = nng_recvmsg( ctx->nn_sock, (nng_msg **) &msg->tp_buf, NO_FLAGS ); // blocks hard until received
339 if( (msg->state = xlate_nng_state( msg->state, RMR_ERR_RCVFAILED )) != RMR_OK ) {
342 rsize = nng_msg_len( msg->tp_buf );
344 // do NOT use ref_tpbuf() here! Must fill these in manually.
345 msg->header = nng_msg_body( msg->tp_buf );
346 msg->len = rsize; // len is the number of bytes received
347 msg->alloc_len = rsize;
348 msg->mtype = -1; // raw message has no type
350 msg->flags = MFL_RAW;
351 msg->payload = msg->header; // payload is the whole thing; no header
354 if( DEBUG > 1 ) fprintf( stderr, "[DBUG] rcv_payload: got something: type=%d state=%d len=%d\n", msg->mtype, msg->state, msg->len );
360 This does the hard work of actually sending the message to the given socket. On success,
361 a new message struct is returned. On error, the original msg is returned with the state
362 set to a reasonable value. If the message being sent as MFL_NOALLOC set, then a new
363 buffer will not be allocated and returned (mostly for call() interal processing since
364 the return message from call() is a received buffer, not a new one).
366 Called by rmr_send_msg() and rmr_rts_msg(), etc. and thus we assume that all pointer
367 validation has been done prior.
369 static rmr_mbuf_t* send_msg( uta_ctx_t* ctx, rmr_mbuf_t* msg, nng_socket nn_sock, int retries ) {
372 int nng_flags = NNG_FLAG_NONBLOCK; // if we need to set any nng flags (zc buffer) add it to this
373 int spin_retries = 1000; // if eagain/timeout we'll spin this many times before giving up the CPU
375 // future: ensure that application did not overrun the XID buffer; last byte must be 0
377 hdr = (uta_mhdr_t *) msg->header;
378 hdr->mtype = htonl( msg->mtype ); // stash type/len in network byte order for transport
379 hdr->plen = htonl( msg->len );
381 if( msg->flags & MFL_ADDSRC ) { // buffer was allocated as a receive buffer; must add our source
382 strncpy( (char *) ((uta_mhdr_t *)msg->header)->src, ctx->my_name, RMR_MAX_SID ); // must overlay the source to be ours
387 if( msg->flags & MFL_ZEROCOPY ) { // faster sending with zcopy buffer
388 //nng_flags |= NNG_FLAG_ALLOC; // indicate a zc buffer that nng is expected to free
391 if( (state = nng_sendmsg( nn_sock, (nng_msg *) msg->tp_buf, nng_flags )) != 0 ) { // must check and retry some if transient failure
393 if( retries > 0 && (state == NNG_EAGAIN || state == NNG_ETIMEDOUT) ) {
394 if( --spin_retries <= 0 ) { // don't give up the processor if we don't have to
396 usleep( 1 ); // sigh, give up the cpu and hope it's just 1 miscrosec
400 state = 0; // don't loop
401 //if( DEBUG ) fprintf( stderr, ">>>>> send failed: %s\n", nng_strerror( state ) );
406 msg->header = NULL; // nano frees; don't risk accessing later by mistake
409 } while( state && retries > 0 );
411 msg->state = RMR_ERR_SENDFAILED;
416 if( (state = nng_send( nn_sock, msg->header, sizeof( uta_mhdr_t ) + msg->len, nng_flags )) != 0 ) {
418 //if( DEBUG ) fprintf( stderr, ">>>>> copy buffer send failed: %s\n", nng_strerror( state ) );
423 if( msg->state == RMR_OK ) { // successful send
424 if( !(msg->flags & MFL_NOALLOC) ) { // allocate another sendable zc buffer unless told otherwise
425 return alloc_zcmsg( ctx, msg, 0, RMR_OK ); // preallocate a zero-copy buffer and return msg
427 rmr_free_msg( msg ); // not wanting a meessage back, trash this one
430 } else { // send failed -- return original message
431 if( msg->state == NNG_EAGAIN || msg->state == NNG_ETIMEDOUT ) {
433 msg->state = RMR_ERR_RETRY; // errno will have nano reason
435 msg->state = xlate_nng_state( msg->state, RMR_ERR_SENDFAILED ); // xlate to our state and set errno
436 //errno = -msg->state;
437 //msg->state = RMR_ERR_SENDFAILED; // errno will have nano reason
440 if( DEBUG ) fprintf( stderr, "[DBUG] send failed: %d %s\n", (int) msg->state, strerror( msg->state ) );
447 A generic wrapper to the real send to keep wormhole stuff agnostic.
448 We assume the wormhole function vetted the buffer so we don't have to.
450 static rmr_mbuf_t* send2ep( uta_ctx_t* ctx, endpoint_t* ep, rmr_mbuf_t* msg ) {
451 return send_msg( ctx, msg, ep->nn_sock, -1 );