3 /* stoken - simple/static token ring */
5 /* Copyright (c) 2005 Alexandre Colucci. */
6 /* Copyright (c) 2005 Martin Quinson. */
7 /* All rights reserved. */
9 /* This program is free software; you can redistribute it and/or modify it
10 * under the terms of the license (GNU LGPL) which comes with this package. */
15 /*#define NBLOOPS 30000*/
17 XBT_LOG_NEW_DEFAULT_CATEGORY(SimpleToken,
18 "Messages specific to this example");
20 /* Function prototypes */
21 int node(int argc, char *argv[]);
24 /* **********************************************************************
26 * **********************************************************************/
28 /* Global private data */
30 gras_socket_t sock; /* server socket on which I hear */
31 int remaining_loop; /* number of loops to do until done */
32 int create; /* whether I have to create the token */
33 gras_socket_t tosuccessor; /* how to connect to the successor on ring */
34 double start_time; /* to measure the elapsed time. Only used by the
35 node that creates the token */
39 /* Callback function */
40 static int node_cb_stoken_handler(gras_msg_cb_ctx_t ctx, void *payload)
45 /* 1. Get the payload into the msg variable, and retrieve my caller */
46 int msg = *(int *) payload;
47 gras_socket_t expeditor = gras_msg_cb_ctx_from(ctx);
50 /* 2. Retrieve the node's state (globals) */
51 node_data_t *globals = (node_data_t *) gras_userdata_get();
53 /* 3. Log which predecessor connected */
54 int supersteps = 1; /* only log every superstep loop */
55 if (NBLOOPS >= 1000) {
57 } else if (NBLOOPS >= 100) {
59 } else if (NBLOOPS <= 10) {
62 if (globals->create && (!(globals->remaining_loop % supersteps))) {
63 INFO1("Begin a new loop. Still to do: %d", globals->remaining_loop);
64 } else if (!(globals->remaining_loop % supersteps)) {
65 VERB3("Got token(%d) from %s remaining_loop=%d",
66 msg, gras_socket_peer_name(expeditor), globals->remaining_loop);
69 /* 4. If the right shouldn't be stopped yet */
70 if (globals->remaining_loop > 0) {
73 DEBUG3("Send token(%d) to %s:%d", msg,
74 gras_socket_peer_name(globals->tosuccessor),
75 gras_socket_peer_port(globals->tosuccessor));
77 /* 5. Send the token as payload of a stoken message to the successor */
79 gras_msg_send(globals->tosuccessor, "stoken", &msg);
81 /* 6. Deal with errors */
84 gras_socket_close(globals->sock);
85 RETHROW0("Unable to forward token: %s");
90 /* DO NOT CLOSE THE expeditor SOCKET since the client socket is
91 reused by our predecessor.
92 Closing this side would thus create troubles */
94 /* 7. Decrease the remaining_loop integer. */
95 globals->remaining_loop -= 1;
97 /* 8. Repport the hop number to the user at the end */
98 if (globals->remaining_loop == -1 && globals->create) {
99 double elapsed = gras_os_time() - globals->start_time;
100 INFO1("Shut down the token-ring. There was %d hops.", msg);
101 VERB1("Elapsed time: %g", elapsed);
104 /* 9. Tell GRAS that we consummed this message */
106 } /* end_of_node_cb_stoken_handler */
108 int node(int argc, char *argv[])
110 node_data_t *globals;
118 /* 1. Init the GRAS infrastructure and declare my globals */
119 gras_init(&argc, argv);
120 globals = gras_userdata_new(node_data_t);
123 /* 2. Get the successor's address. The command line overrides
124 defaults when specified */
129 myport = atoi(argv[1]);
131 peerport = atoi(argv[3]);
134 /* 3. Save successor's address in global var */
135 globals->remaining_loop = NBLOOPS;
137 globals->tosuccessor = NULL;
139 if (!gras_os_getpid() % 100 || gras_if_RL())
140 INFO3("Launch node listening on %d (successor on %s:%d)",
141 myport, host, peerport);
143 /* 4. Register the known messages. */
144 gras_msgtype_declare("stoken", gras_datadesc_by_name("int"));
146 /* 5. Create my master socket for listening */
147 globals->sock = gras_socket_server(myport);
148 gras_os_sleep(1.0); /* Make sure all server sockets are created */
150 /* 6. Create socket to the successor on the ring */
151 DEBUG2("Connect to my successor on %s:%d", host, peerport);
153 globals->tosuccessor = gras_socket_client(host, peerport);
155 /* 7. Register my callback */
156 gras_cb_register("stoken", &node_cb_stoken_handler);
158 /* 8. One node has to create the token at startup.
159 It's specified by a command line argument */
161 && !strncmp("--create-token", argv[4], strlen("--create-token")))
164 if (globals->create) {
167 globals->start_time = gras_os_time();
169 globals->remaining_loop = NBLOOPS - 1;
171 INFO3("Create the token (with value %d) and send it to %s:%d",
172 token, host, peerport);
175 gras_msg_send(globals->tosuccessor, "stoken", &token);
177 RETHROW0("Unable to send the freshly created token: %s");
181 /* 8. Wait up to 10 seconds for an incomming message to handle */
182 while (globals->remaining_loop > (globals->create ? -1 : 0)) {
185 DEBUG1("looping (remaining_loop=%d)", globals->remaining_loop);
188 gras_os_sleep(1.0); /* FIXME: if the sender quited, receive fail */
190 /* 9. Free the allocated resources, and shut GRAS down */
191 gras_socket_close(globals->sock);
192 gras_socket_close(globals->tosuccessor);