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/*
* Check effectiveness of umovestr memory caching.
*
* Copyright (c) 2019-2021 Dmitry V. Levin <ldv@strace.io>
* All rights reserved.
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "tests.h"
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <sys/uio.h>
int
main(void)
{
char *const buf = tail_alloc(DEFAULT_STRLEN);
fill_memory_ex(buf, DEFAULT_STRLEN, 'a', 'z' - 'a' + 1);
struct iovec *const io = tail_alloc(sizeof(*io) * DEFAULT_STRLEN);
for (unsigned int i = 0; i < DEFAULT_STRLEN; ++i) {
io[i].iov_base = buf + DEFAULT_STRLEN - i;
io[i].iov_len = i;
}
tprintf("%s", "");
int rc = writev(-1, io, DEFAULT_STRLEN);
const char *errstr = sprintrc(rc);
tprintf("writev(-1, [");
for (unsigned int i = 0; i < DEFAULT_STRLEN; ++i) {
if (i)
tprintf(", ");
tprintf("{iov_base=\"%.*s\", iov_len=%u}",
(int) io[i].iov_len,
(char *) io[i].iov_base,
(unsigned int) io[i].iov_len);
}
tprintf("], %u) = %s\n", DEFAULT_STRLEN, errstr);
tprintf("+++ exited with 0 +++\n");
return 0;
}
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