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/*
* basic test for seqlock
*
* Copyright (C) 2015 David Lamparter
*
* This program 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.
*
* This program 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
* this program; if not, write to the Free Software Foundation, Inc., 59 Temple
* Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>
#include <string.h>
#include <unistd.h>
#include <assert.h>
#include <sys/uio.h>
#include "monotime.h"
#include "seqlock.h"
static struct seqlock sqlo;
static pthread_t thr1;
static struct timeval start;
static void writestr(const char *str)
{
struct iovec iov[2];
char buf[32];
int64_t usec = monotime_since(&start, NULL);
snprintf(buf, sizeof(buf), "[%02"PRId64"] ", usec / 100000);
iov[0].iov_base = buf;
iov[0].iov_len = strlen(buf);
iov[1].iov_base = (char *)str;
iov[1].iov_len = strlen(str);
writev(1, iov, 2);
}
static void *thr1func(void *arg)
{
assert(!seqlock_held(&sqlo));
assert(seqlock_check(&sqlo, 1));
seqlock_wait(&sqlo, 1);
writestr("thr1 (unheld)\n");
sleep(2);
assert(seqlock_held(&sqlo));
assert(seqlock_check(&sqlo, 1));
seqlock_wait(&sqlo, 1);
writestr("thr1 @1\n");
seqlock_wait(&sqlo, 3);
writestr("thr1 @3\n");
seqlock_wait(&sqlo, 5);
writestr("thr1 @5\n");
seqlock_wait(&sqlo, 7);
writestr("thr1 @7\n");
seqlock_wait(&sqlo, 9);
writestr("thr1 @9\n");
seqlock_wait(&sqlo, 11);
writestr("thr1 @11\n");
return NULL;
}
int main(int argc, char **argv)
{
monotime(&start);
seqlock_init(&sqlo);
assert(!seqlock_held(&sqlo));
seqlock_acquire_val(&sqlo, 1);
assert(seqlock_held(&sqlo));
assert(seqlock_cur(&sqlo) == 1);
assert(seqlock_bump(&sqlo) == 1);
assert(seqlock_cur(&sqlo) == 3);
assert(seqlock_bump(&sqlo) == 3);
assert(seqlock_bump(&sqlo) == 5);
assert(seqlock_bump(&sqlo) == 7);
assert(seqlock_cur(&sqlo) == 9);
assert(seqlock_held(&sqlo));
seqlock_release(&sqlo);
assert(!seqlock_held(&sqlo));
pthread_create(&thr1, NULL, thr1func, NULL);
sleep(1);
writestr("main @3\n");
seqlock_acquire_val(&sqlo, 3);
sleep(2);
writestr("main @5\n");
seqlock_bump(&sqlo);
sleep(1);
writestr("main @9\n");
seqlock_acquire_val(&sqlo, 9);
sleep(1);
writestr("main @release\n");
seqlock_release(&sqlo);
sleep(1);
}
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