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/*
* Copyright (c) 2014-2016 Dmitry V. Levin <ldv@strace.io>
* Copyright (c) 2016-2024 The strace developers.
* All rights reserved.
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "tests.h"
#ifdef HAVE_PWRITEV
# include <fcntl.h>
# include <stdio.h>
# include <sys/uio.h>
# include <unistd.h>
# define LEN 8
# define LIM (LEN - 1)
static void
print_iov(const struct iovec *iov)
{
unsigned int i;
unsigned char *buf = iov->iov_base;
fputs("{iov_base=\"", stdout);
for (i = 0; i < iov->iov_len; ++i) {
if (i < LIM)
printf("\\%d", (int) buf[i]);
}
printf("\"%s, iov_len=%u}",
i > LIM ? "..." : "", (unsigned) iov->iov_len);
}
static void
print_iovec(const struct iovec *iov, unsigned int cnt, unsigned int size)
{
if (!size) {
printf("%p", iov);
return;
}
putchar('[');
for (unsigned int i = 0; i < cnt; ++i) {
if (i)
fputs(", ", stdout);
if (i == size) {
printf("... /* %p */", &iov[i]);
break;
}
if (i == LIM) {
fputs("...", stdout);
break;
}
print_iov(&iov[i]);
}
putchar(']');
}
/* for pwritev(0, NULL, 1, -3) */
DIAG_PUSH_IGNORE_NONNULL
int
main(void)
{
(void) close(0);
if (open("/dev/null", O_WRONLY))
perror_msg_and_fail("open");
char *buf = tail_alloc(LEN);
for (unsigned int i = 0; i < LEN; ++i)
buf[i] = i;
TAIL_ALLOC_OBJECT_VAR_ARR(struct iovec, iov, LEN);
for (unsigned int i = 0; i < LEN; ++i) {
buf[i] = i;
iov[i].iov_base = &buf[i];
iov[i].iov_len = LEN - i;
}
const off_t offset = 0xdefaceddeadbeefLL;
long rc;
int written = 0;
for (unsigned int i = 0; i < LEN; ++i) {
written += iov[i].iov_len;
if (pwritev(0, iov, i + 1, offset + i) != written)
perror_msg_and_fail("pwritev");
fputs("pwritev(0, ", stdout);
print_iovec(iov, i + 1, LEN);
printf(", %u, %lld) = %d\n",
i + 1, (long long) offset + i, written);
}
for (unsigned int i = 0; i <= LEN; ++i) {
unsigned int n = LEN + 1 - i;
fputs("pwritev(0, ", stdout);
print_iovec(iov + i, n, LEN - i);
rc = pwritev(0, iov + i, n, offset + LEN + i);
printf(", %u, %lld) = %s\n",
n, (long long) offset + LEN + i, sprintrc(rc));
}
iov->iov_base = iov + LEN * 2;
rc = pwritev(0, iov, 1, -1);
printf("pwritev(0, [{iov_base=%p, iov_len=%d}], 1, -1) = %s\n",
iov->iov_base, LEN, sprintrc(rc));
iov += LEN;
rc = pwritev(0, iov, 42, -2);
printf("pwritev(0, %p, 42, -2) = %s\n",
iov, sprintrc(rc));
rc = pwritev(0, NULL, 1, -3);
printf("pwritev(0, NULL, 1, -3) = %s\n",
sprintrc(rc));
rc = pwritev(0, iov, 0, -4);
printf("pwritev(0, [], 0, -4) = %s\n",
sprintrc(rc));
puts("+++ exited with 0 +++");
return 0;
}
DIAG_POP_IGNORE_NONNULL
#else
SKIP_MAIN_UNDEFINED("HAVE_PWRITEV")
#endif
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