1 // vim: noet sw=4 ts=4:
3 ==================================================================================
4 Copyright (c) 2020-2021 Nokia
5 Copyright (c) 2020-2021 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 **************************************************************************
24 * Abstract: This routine will wait for an event to occur on the
25 * connections in tplist. When an event is received on a fd
26 * the status of the fd is checked and the event handled, driving
27 * a callback routine if necessary. The system call poll is usd
28 * to wait, and will be interrupted if a signal is caught,
29 * therefore the routine will handle any work that is required
30 * when a signal is received. The routine continues to loop
31 * until the shutdown flag is set, or until there are no open
32 * file descriptors on which to wait.
33 * Parms: gptr - Pointer to the global information block
34 * Returns: SI_OK if the caller can continue, SI_ERROR if all sessions have been
35 * stopped, or the interface cannot proceed. When SI_ERROR is
36 * returned the caller should cleanup and exit immediatly (we
37 * have probably received a sigter or sigquit.
39 * Author: E. Scott Daniels
41 * Modified: 11 Apr 1995 - To pass execption to select when no keyboard
42 * 19 Apr 1995 - To call do key to do better keyboard editing
43 * 18 Aug 1995 - To init kstat to 0 to prevent key hold if
44 * network data pending prior to entry.
45 * 31 Jul 2016 - Major formatting clean up in the main while loop.
46 **************************************************************************
48 #include "sisetup.h" // get the setup stuff
49 #include "sitransport.h"
53 The select timeout is about 300 mu-sec. This is fast enough to add a new
54 outbound connection to the poll list before the other side responds,
55 but slow enough so as not to consume excess CPU when idle.
57 #define SI_SELECT_TIMEOUT 300000
59 #ifndef SYSTEM_UNDER_TEST
60 # define SYSTEM_UNDER_TEST 0
63 extern int SIwait( struct ginfo_blk *gptr ) {
64 int fd = -1; // file descriptor for use in this routine
65 int ((*cbptr)()); // pointer to callback routine to call
66 int status = SI_OK; // return status
67 int addrlen = 0; // length of address from recvfrom call
69 struct tp_blk *tpptr = NULL; // pointer at tp stuff
70 struct tp_blk *nextone= NULL; // point at next block to process in loop
71 int pstat = 0; // poll status
72 struct timeval timeout; // delay to use on select call
74 if( gptr->magicnum != MAGICNUM ) { // if not a valid ginfo block
75 rmr_vlog( RMR_VL_CRIT, "SI95: wait: bad global info struct magic number is wrong\n" );
79 if( gptr->flags & GIF_SHUTDOWN ) { // cannot do if we should shutdown
80 return SI_ERROR; // so just get out
83 do { // spin until a callback says to stop (likely never)
84 timeout.tv_sec = 0; // must be reset on every call!
85 timeout.tv_usec = SI_SELECT_TIMEOUT;
87 SIbldpoll( gptr ); // poll list is trashed on each pop; must rebuild
88 pstat = select( gptr->fdcount, &gptr->readfds, &gptr->writefds, &gptr->execpfds, &timeout );
90 if( (pstat < 0 && errno != EINTR) ) {
91 gptr->fdcount = 0; // prevent trying to look at a session
92 gptr->flags |= GIF_SHUTDOWN; // cause cleanup and exit at end
95 if( pstat > 0 && (! (gptr->flags & GIF_SHUTDOWN)) ) {
97 while( tpptr != NULL ) {
98 nextone = tpptr->next; // prevent issues if we delete the block during loop
100 if( tpptr->fd >= 0 ) {
101 if( tpptr->squeue != NULL && (FD_ISSET( tpptr->fd, &gptr->writefds )) ) {
102 SIsend( gptr, tpptr ); // send if clear to send
105 if( FD_ISSET( tpptr->fd, &gptr->execpfds ) ) {
106 ; // sunos seems to set the except flag for unknown reasons; ignore it
108 if( FD_ISSET( tpptr->fd, &gptr->readfds ) ) { // ready to read
112 if( tpptr->flags & TPF_LISTENFD ) { // new session request
114 status = SInewsession( gptr, tpptr ); // accept connection
115 } else { // data received on a regular port (we support just tcp now
116 status = RECV( fd, gptr->rbuf, MAX_RBUF, 0 ); // read data
117 if( status > 0 && ! (tpptr->flags & TPF_DRAIN) ) {
118 if( (cbptr = gptr->cbtab[SI_CB_CDATA].cbrtn) != NULL ) {
119 status = (*cbptr)( gptr->cbtab[SI_CB_CDATA].cbdata, fd, gptr->rbuf, status );
120 SIcbstat( gptr, status, SI_CB_CDATA ); // handle cb status
122 } else { // no bites, but read flagged indicates disconnect
123 if( (cbptr = gptr->cbtab[SI_CB_DISC].cbrtn) != NULL ) {
124 status = (*cbptr)( gptr->cbtab[SI_CB_DISC].cbdata, tpptr->fd );
125 SIcbstat( gptr, status, SI_CB_DISC ); // handle status
127 SIterm( gptr, tpptr ); // close FD and mark block for deletion
132 } // if still good fd
138 if( SYSTEM_UNDER_TEST ) { // enabled only during uint testing to prevent blocking
141 } while( gptr->tplist != NULL && !(gptr->flags & GIF_SHUTDOWN) );
143 if( gptr->tplist == NULL ) // indicate all fds closed
145 if( gptr->flags & GIF_SHUTDOWN ) { // we need to stop for some reason
146 status = SI_ERROR; // status should indicate to user to die
147 SIshutdown( gptr ); // clean things up
149 status = SI_OK; // user can continue to process