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/*
* This file is part of libtrace
*
* Copyright (c) 2007 The University of Waikato, Hamilton, New Zealand.
* Authors: Daniel Lawson
* Perry Lorier
*
* All rights reserved.
*
* This code has been developed by the University of Waikato WAND
* research group. For further information please see http://www.wand.net.nz/
*
* libtrace is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* libtrace is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with libtrace; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* $Id: rate-tracetime.c 551 2005-12-15 01:16:33Z spa1 $
*
*/
/* This is a simple example program that demonstrates how to use the libtrace
* event framework. The event framework is ideal for reading from devices and
* interfaces in a non-blocking manner, and for reading from a trace in
* "tracetime" as opposed to as fast as possible.
*/
#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include <sys/types.h>
#include <unistd.h>
#include <string.h>
#include <libtrace.h>
static void per_packet(libtrace_packet_t *packet) {
assert(packet);
/* Your code goes here */
}
static uint32_t event_read_packet(libtrace_t *trace, libtrace_packet_t *packet)
{
libtrace_eventobj_t obj;
fd_set rfds;
struct timeval sleep_tv;
FD_ZERO(&rfds);
for (;;) {
obj = trace_event(trace, packet);
switch(obj.type) {
/* Device has no packets at present - lets wait until
* it does get something */
case TRACE_EVENT_IOWAIT:
FD_ZERO(&rfds);
FD_SET(obj.fd, &rfds);
select(obj.fd + 1, &rfds, NULL, NULL, 0);
continue;
/* Replaying a trace in tracetime and the next packet
* is not due yet */
case TRACE_EVENT_SLEEP:
/* select offers good precision for sleeping */
sleep_tv.tv_sec = (int)obj.seconds;
sleep_tv.tv_usec = (int) ((obj.seconds - sleep_tv.tv_sec) * 1000000.0);
select(0, NULL, NULL, NULL, &sleep_tv);
continue;
/* We've got a packet! */
case TRACE_EVENT_PACKET:
/* Check for error first */
if (obj.size == -1)
return -1;
return 1;
/* End of trace has been reached */
case TRACE_EVENT_TERMINATE:
return -1;
/* An event we don't know about has occured */
default:
fprintf(stderr, "Unknown event type occured\n");
return -1;
}
}
}
int main(int argc, char *argv[]) {
libtrace_t *trace;
libtrace_packet_t *packet;
int psize = 0;
char *uri = 0;
if (argc >= 2) {
uri = strdup(argv[1]);
} else {
fprintf(stderr, "Usage: event_example <uri>\n");
return -1;
}
/* Create the trace */
trace = trace_create(uri);
if (trace_is_err(trace)) {
trace_perror(trace, "trace_create");
return 0;
}
/* Starting the trace */
if (trace_start(trace) != 0) {
trace_perror(trace, "trace_start");
return 0;
}
packet = trace_create_packet();
for (;;) {
if ((psize = event_read_packet(trace, packet)) <= 0) {
break;
}
/* Got a packet - let's do something with it */
per_packet(packet);
}
free(uri);
trace_destroy(trace);
trace_destroy_packet(packet);
return 0;
}
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