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
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18 ==================================================================================
23 Abstract: These are static send/receive related functions.
26 Author: E. Scott Daniels
27 Date: 13 February 2019
45 #include <arpa/inet.h>
47 #include <nanomsg/nn.h>
48 #include <nanomsg/tcp.h>
49 #include <nanomsg/pair.h>
50 #include <nanomsg/pipeline.h>
51 #include <nanomsg/pubsub.h>
53 #include "rmr.h" // things the users see
54 #include "rmr_private.h" // things that we need too
55 #include "rmr_symtab.h"
57 #include "ring_static.c" // message ring support
58 #include "rt_generic_static.c" // generic route table (not nng/nano specific)
59 #include "rtable_static.c" // route table things (nano specific)
60 #include "tools_static.c"
65 Alloc a new nano zero copy buffer and put into msg. If msg is nil, then we will alloc
66 a new message struct as well. Size is the size of the zc buffer to allocate (not
67 including our header). If size is 0, then the buffer allocated is the size previously
68 allocated (if msg is !nil) or the default size given at initialisation).
70 static rmr_mbuf_t* alloc_zcmsg( uta_ctx_t* ctx, rmr_mbuf_t* msg, int size, int state ) {
73 mlen = sizeof( uta_mhdr_t ); // figure size should we not have a msg buffer
74 mlen += (size > 0 ? size : ctx->max_plen); // add user requested size or size set during init
77 msg = (rmr_mbuf_t *) malloc( sizeof *msg );
79 fprintf( stderr, "[CRIT] rmr_alloc_zc: cannot get memory for message\n" );
83 mlen = msg->alloc_len; // msg given, allocate the same size as before
86 memset( msg, 0, sizeof( *msg ) );
88 if( (msg->header = (uta_mhdr_t *) nn_allocmsg( mlen, 0 )) == NULL ) { // this will be released on send, so DO NOT free
89 fprintf( stderr, "[CRIT] rmr_alloc_zc: cannot get memory for zero copy buffer: %d\n", errno );
93 ((uta_mhdr_t *) msg->header)->rmr_ver = RMR_MSG_VER; // version info should we need to recognised old style messages someday
94 msg->len = 0; // length of data in the payload
95 msg->alloc_len = mlen; // length of allocated payload
96 msg->payload = msg->header + sizeof( uta_mhdr_t ); // point past header to payload (single buffer allocation above)
97 msg->xaction = ((uta_mhdr_t *)msg->header)->xid; // point at transaction id in header area
98 msg->state = state; // fill in caller's state (likely the state of the last operation)
99 msg->flags |= MFL_ZEROCOPY; // this is a zerocopy sendable message
100 strncpy( (char *) ((uta_mhdr_t *)msg->header)->src, ctx->my_name, RMR_MAX_SID );
102 if( DEBUG > 1 ) fprintf( stderr, "[DBUG] alloc_zcmsg mlen = %d size=%d mpl=%d flags=%02x %p m=%p @%p\n", mlen, size, ctx->max_plen, msg->flags, &msg->flags, msg, msg->header );
108 This will clone a message into a new zero copy buffer and return the cloned message.
110 static inline rmr_mbuf_t* clone_msg( rmr_mbuf_t* old_msg ) {
111 rmr_mbuf_t* nm; // new message buffer
114 if( old_msg == NULL ) {
118 nm = (rmr_mbuf_t *) malloc( sizeof *nm );
120 fprintf( stderr, "[CRIT] rmr_clone: cannot get memory for message buffer\n" );
123 memset( nm, 0, sizeof( *nm ) );
125 mlen = old_msg->alloc_len; // length allocated before
126 if( (nm->header = (uta_mhdr_t *) nn_allocmsg( mlen, 0 )) == NULL ) { // this will be released on send, so DO NOT free
127 fprintf( stderr, "[CRIT] rmr_clone: cannot get memory for zero copy buffer: %d\n", errno );
131 nm->mtype = old_msg->mtype;
132 nm->len = old_msg->len; // length of data in the payload
133 nm->alloc_len = mlen; // length of allocated payload
134 nm->payload = nm->header + sizeof( uta_mhdr_t ); // point past header to payload (single buffer allocation above)
135 nm->xaction = ((uta_mhdr_t *)nm->header)->xid; // point at transaction id in header area
136 nm->state = old_msg->state; // fill in caller's state (likely the state of the last operation)
137 nm->flags |= MFL_ZEROCOPY; // this is a zerocopy sendable message
138 memcpy( ((uta_mhdr_t *)nm->header)->src, ((uta_mhdr_t *)old_msg->header)->src, RMR_MAX_SID );
139 memcpy( nm->payload, old_msg->payload, old_msg->len );
145 This is the receive work horse used by the outer layer receive functions.
146 It waits for a message to be received on our listen socket. If old msg
147 is passed in, the we assume we can use it instead of allocating a new
148 one, else a new block of memory is allocated.
150 This allocates a zero copy message so that if the user wishes to call
151 uta_rts_msg() the send is zero copy.
153 static rmr_mbuf_t* rcv_msg( uta_ctx_t* ctx, rmr_mbuf_t* old_msg ) {
154 int nn_sock; // endpoint socket for send
156 rmr_mbuf_t* msg = NULL; // msg received
162 msg = alloc_zcmsg( ctx, NULL, RMR_MAX_RCV_BYTES, RMR_OK ); // will abort on failure, no need to check
165 msg->state = nn_recv( ctx->nn_sock, msg->header, msg->alloc_len, NO_FLAGS ); // total space (header + payload len) allocated
166 if( msg->state > (int) sizeof( uta_mhdr_t ) ) { // we need more than just a header here
167 hdr = (uta_mhdr_t *) msg->header;
168 msg->len = ntohl( hdr->plen ); // length of data in the payload (likely < payload size)
169 if( msg->len > msg->state - sizeof( uta_mhdr_t ) ) {
170 fprintf( stderr, "[WARN] rmr_rcv indicated payload length < rcvd payload: expected %d got %ld\n",
171 msg->len, msg->state - sizeof( uta_mhdr_t ) );
173 msg->mtype = ntohl( hdr->mtype ); // capture and convert from network order to local order
175 msg->flags |= MFL_ADDSRC; // turn on so if user app tries to send this buffer we reset src
176 msg->payload = msg->header + sizeof( uta_mhdr_t );
177 msg->xaction = &hdr->xid[0]; // provide user with ref to fixed space xaction id
178 if( DEBUG > 1 ) fprintf( stderr, "[DBUG] rcv_msg: got something: type=%d state=%d len=%d diff=%ld\n",
179 msg->mtype, msg->state, msg->len, msg->payload - (unsigned char *) msg->header );
182 msg->state = RMR_ERR_EMPTY;
190 Receives a 'raw' message from a non-RMr sender (no header expected). The returned
191 message buffer cannot be used to send, and the length information may or may
192 not be correct (it is set to the length received which might be more than the
193 bytes actually in the payload).
195 static void* rcv_payload( uta_ctx_t* ctx, rmr_mbuf_t* old_msg ) {
196 int nn_sock; // endpoint socket for send
198 rmr_mbuf_t* msg = NULL; // msg received
203 msg = alloc_zcmsg( ctx, NULL, RMR_MAX_RCV_BYTES, RMR_OK ); // will abort on failure, no need to check
206 msg->state = nn_recv( ctx->nn_sock, msg->header, msg->alloc_len, NO_FLAGS ); // read and state will be length
207 if( msg->state >= 0 ) {
210 msg->len = msg->state; // no header; len is the entire thing received
212 msg->flags = MFL_RAW; // prevent any sending of this headerless buffer
213 msg->payload = msg->header;
214 if( DEBUG > 1 ) fprintf( stderr, "[DBUG] rcv_payload: got something: type=%d state=%d len=%d\n", msg->mtype, msg->state, msg->len );
217 msg->state = RMR_ERR_EMPTY;
227 This does the hard work of actually sending the message to the given socket. On success,
228 a new message struct is returned. On error, the original msg is returned with the state
229 set to a reasonable value. If the message being sent as MFL_NOALLOC set, then a new
230 buffer will not be allocated and returned (mostly for call() interal processing since
231 the return message from call() is a received buffer, not a new one).
233 Called by rmr_send_msg() and rmr_rts_msg().
235 static rmr_mbuf_t* send_msg( uta_ctx_t* ctx, rmr_mbuf_t* msg, int nn_sock ) {
239 // future: ensure that application did not overrun the XID buffer; last byte must be 0
241 hdr = (uta_mhdr_t *) msg->header;
242 hdr->mtype = htonl( msg->mtype ); // stash type/len in network byte order for transport
243 hdr->plen = htonl( msg->len );
245 if( msg->flags & MFL_ADDSRC ) { // buffer was allocated as a receive buffer; must add our source
246 strncpy( (char *) ((uta_mhdr_t *)msg->header)->src, ctx->my_name, RMR_MAX_SID ); // must overlay the source to be ours
249 if( msg->flags & MFL_ZEROCOPY ) { // faster sending with zcopy buffer
250 if( (state = nn_send( nn_sock, &msg->header, NN_MSG, NN_DONTWAIT )) < 0 ) {
253 msg->header = NULL; // nano frees; don't risk accessing later by mistake
256 if( (state = nn_send( nn_sock, msg->header, sizeof( uta_mhdr_t ) + msg->len, NN_DONTWAIT )) < 0 ) {
261 // future: if nano sends bytes, but less than mlen, then what to do?
262 if( msg->state >= 0 ) { // successful send
263 if( !(msg->flags & MFL_NOALLOC) ) { // if noalloc is set, then caller doesn't want a new buffer
264 return alloc_zcmsg( ctx, msg, 0, RMR_OK ); // preallocate a zero-copy buffer and return msg
266 rmr_free_msg( msg ); // not wanting a meessage back, trash this one
269 } else { // send failed -- return original message
270 if( errno == EAGAIN ) {
271 msg->state = RMR_ERR_RETRY; // some wrappers can't see errno, make this obvious
273 msg->state = RMR_ERR_SENDFAILED; // errno will have nano reason
275 if( DEBUG ) fprintf( stderr, "[DBUG] send failed: %s\n", strerror( errno ) );
283 A generic wrapper to the real send to keep wormhole stuff agnostic.
284 We assume the wormhole function vetted the buffer so we don't have to.
286 static rmr_mbuf_t* send2ep( uta_ctx_t* ctx, endpoint_t* ep, rmr_mbuf_t* msg ) {
287 return send_msg( ctx, msg, ep->nn_sock );