SimGrid  3.16
Versatile Simulation of Distributed Systems
examples/msg/app-token-ring/app-token-ring.c
/* Copyright (c) 2008-2016. The SimGrid Team. All rights reserved. */
/* This program is free software; you can redistribute it and/or modify it
* under the terms of the license (GNU LGPL) which comes with this package. */
#include "simgrid/msg.h"
XBT_LOG_NEW_DEFAULT_CATEGORY(msg_app_token_ring, "Messages specific for this msg example");
/* Main function of all processes used in this example */
static int relay_runner(int argc, char *argv[])
{
xbt_assert(argc==0, "The relay_runner function does not accept any parameter from the XML deployment file");
int rank = xbt_str_parse_int(MSG_process_get_name(MSG_process_self()), "Any process of this example must have a numerical name, not %s");
char mailbox[256];
if (rank == 0) {
/* The root process (rank 0) first sends the token then waits to receive it back */
snprintf(mailbox,255, "%d", rank+1);
unsigned int task_comm_size = 1000000; /* The token is 1MB long*/
msg_task_t task = MSG_task_create("Token", 0, task_comm_size, NULL);
XBT_INFO("Host \"%d\" send '%s' to Host \"%s\"", rank, task->name,mailbox);
MSG_task_send(task, mailbox);
task = NULL;
xbt_assert(res == MSG_OK, "MSG_task_get failed");
XBT_INFO("Host \"%d\" received \"%s\"", rank, MSG_task_get_name(task));
} else {
/* The others processes receive from their left neighbor (rank-1) and send to their right neighbor (rank+1) */
msg_task_t task = NULL;
xbt_assert(res == MSG_OK, "MSG_task_get failed");
XBT_INFO("Host \"%d\" received \"%s\"",rank, MSG_task_get_name(task));
if (rank+1 == MSG_get_host_number())
/* But the last process, which sends the token back to rank 0 */
snprintf(mailbox,255, "0");
else
snprintf(mailbox,255, "%d", rank+1);
XBT_INFO("Host \"%d\" send '%s' to Host \"%s\"",rank,task->name,mailbox);
MSG_task_send(task, mailbox);
}
return 0;
}
int main(int argc, char *argv[])
{
MSG_init(&argc, argv);
xbt_assert(argc>1, "Usage: %s platform.xml\n",argv[0]);
MSG_create_environment(argv[1]); /* - Load the platform description */
XBT_INFO("Number of hosts '%d'", MSG_get_host_number());
unsigned int i;
xbt_dynar_foreach (hosts, i, h) { /* - Give a unique rank to each host and create a @ref relay_runner process on each */
char* name_host = bprintf("%u",i);
MSG_process_create(name_host, relay_runner, NULL, h);
free(name_host);
}
xbt_dynar_free(&hosts);
int res = MSG_main(); /* - Run the simulation */
XBT_INFO("Simulation time %g", MSG_get_clock());
return res != MSG_OK;
}