3 /* rl_transport - RL specific functions for transport */
5 /* Copyright (c) 2004 Martin Quinson. All rights reserved. */
7 /* This program is free software; you can redistribute it and/or modify it
8 * under the terms of the license (GNU LGPL) which comes with this package. */
11 #include "gras/Transport/transport_private.h"
12 XBT_LOG_EXTERNAL_CATEGORY(transport);
13 XBT_LOG_DEFAULT_CATEGORY(transport);
18 * Returns the next socket to service having a message awaiting.
20 * if timeout<0, we ought to implement the adaptative timeout (FIXME)
22 * if timeout=0, do not wait for new message, only handle the ones already there.
24 * if timeout>0 and no message there, wait at most that amount of time before giving up.
27 gras_trp_select(double timeout,
31 xbt_dynar_t sockets= gras_socketset_get();
33 double wakeup = gras_os_time() + 1000000*timeout;
35 /* nextToService used to make sure socket with high number do not starve */
36 /* static int nextToService = 0; */
37 struct timeval tout, *p_tout;
39 int max_fds=0; /* first arg of select: number of existing sockets */
41 int ready; /* return of select: number of socket ready to be serviced */
43 gras_socket_t sock_iter; /* iterating over all sockets */
44 int cursor; /* iterating over all sockets */
48 if (timeout > 0) { /* did we timeout already? */
50 if (now == -1 || now >= wakeup) {
51 done = 0; /* didn't find anything */
56 /* construct the set of socket to ear from */
58 xbt_dynar_foreach(sockets,cursor,sock_iter) {
59 if (sock_iter->incoming) {
60 if (max_fds < sock_iter->sd)
61 max_fds = sock_iter->sd;
62 FD_SET(sock_iter->sd, &FDS);
64 DEBUG1("Not considering socket %d for select",sock_iter->sd);
68 /* we cannot have more than FD_SETSIZE sockets */
69 if (++max_fds > FD_SETSIZE) {
70 WARN0("too many open sockets.");
77 tout.tv_sec = (unsigned long)((wakeup - now)/1000000);
78 tout.tv_usec = (unsigned long)(wakeup - now) % 1000000;
80 } else if (timeout == 0) {
85 /* we just do one loop around */
88 /* no timeout: good luck! */
92 DEBUG1("Selecting over %d socket(s)", max_fds-1);
93 ready = select(max_fds, &FDS, NULL, NULL, p_tout);
96 case EINTR: /* a signal we don't care about occured. we don't care */
97 /* if we cared, we would have set an handler */
99 case EINVAL: /* invalid value */
100 RAISE3(system_error,"invalid select: nb fds: %d, timeout: %d.%d",
101 max_fds, (int)tout.tv_sec,(int) tout.tv_usec);
103 xbt_assert0(0,"Malloc error during the select");
105 RAISE2(system_error,"Error during select: %s (%d)",
106 strerror(errno),errno);
109 } else if (ready == 0) {
110 continue; /* this was a timeout */
113 xbt_dynar_foreach(sockets,cursor,sock_iter) {
114 if(!FD_ISSET(sock_iter->sd, &FDS)) { /* this socket is not ready */
118 /* Got a socket to serve */
121 if ( sock_iter->accepting
122 && sock_iter->plugin->socket_accept) {
123 /* not a socket but an ear. accept on it and serve next socket */
124 gras_socket_t accepted;
126 TRY(sock_iter->plugin->socket_accept(sock_iter,&accepted));
127 accepted->raw = sock_iter->raw;
130 FIXME: this fails of files. quite logical
131 /* Make sure the socket is still alive by reading the first byte */
135 recvd = recv(sock_iter->sd, &lookahead, 1, MSG_PEEK);
137 WARN2("socket %d failed: %s", sock_iter->sd, strerror(errno));
138 /* done with this socket */
139 gras_socket_close(&sock_iter);
141 } else if (recvd == 0) {
142 /* Connection reset (=closed) by peer. */
143 DEBUG1("Connection %d reset by peer", sock_iter->sd);
144 gras_socket_close(&sock_iter);
148 /* Got a suited socket ! */
157 /* if we're here, the socket we found wasn't really ready to be served */
158 if (ready == 0) /* exausted all sockets given by select. Request new ones */
164 return timeout_error;
167 xbt_error_t gras_trp_sg_setup(gras_trp_plugin_t *plug) {
168 return mismatch_error;