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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* basic test for seqlock
*
* Copyright (C) 2015 David Lamparter
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#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"
#include "printfrr.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);
snprintfrr(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, 5);
writestr("thr1 @5\n");
seqlock_wait(&sqlo, 9);
writestr("thr1 @9\n");
seqlock_wait(&sqlo, 13);
writestr("thr1 @13\n");
seqlock_wait(&sqlo, 17);
writestr("thr1 @17\n");
seqlock_wait(&sqlo, 21);
writestr("thr1 @21\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) == 5);
assert(seqlock_bump(&sqlo) == 5);
assert(seqlock_bump(&sqlo) == 9);
assert(seqlock_bump(&sqlo) == 13);
assert(seqlock_cur(&sqlo) == 17);
assert(seqlock_held(&sqlo));
seqlock_release(&sqlo);
assert(!seqlock_held(&sqlo));
pthread_create(&thr1, NULL, thr1func, NULL);
sleep(1);
writestr("main @5\n");
seqlock_acquire_val(&sqlo, 5);
sleep(2);
writestr("main @9\n");
seqlock_bump(&sqlo);
sleep(1);
writestr("main @17\n");
seqlock_acquire_val(&sqlo, 17);
sleep(1);
writestr("main @release\n");
seqlock_release(&sqlo);
sleep(1);
}
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