mirror of
git://sourceware.org/git/glibc.git
synced 2024-12-15 04:20:28 +08:00
119 lines
3.4 KiB
C
119 lines
3.4 KiB
C
/* Copyright (C) 2011-2024 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
The GNU C Library 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
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with the GNU C Library; if not, see
|
|
<https://www.gnu.org/licenses/>. */
|
|
|
|
#include <fcntl.h>
|
|
#include <limits.h>
|
|
#include <paths.h>
|
|
#include <stdio.h>
|
|
#include <stdint.h>
|
|
#include <stdlib.h>
|
|
#include <unistd.h>
|
|
#include <sys/uio.h>
|
|
|
|
/* GNU/Hurd does not define a IOV_MAX constraint. */
|
|
#ifndef IOV_MAX
|
|
# define IOV_MAX 1024
|
|
#endif
|
|
|
|
|
|
/* The purpose of this test is to verify that the INTERNAL_[V]SYSCALL_NCS
|
|
macros on 64-bit platforms don't cast the return type to (int) which would
|
|
erroneously sign extend the return value should the high bit of the bottom
|
|
half of the word be '1'. */
|
|
|
|
#if 0
|
|
/* Used to test the non power-of-2 code path. */
|
|
#undef IOV_MAX
|
|
#define IOV_MAX 1000
|
|
#endif
|
|
|
|
/* writev() should report that it has written EXPECTED number of bytes. */
|
|
#define EXPECTED ((size_t) INT32_MAX + 1)
|
|
|
|
static int
|
|
do_test (void)
|
|
{
|
|
struct iovec iv[IOV_MAX];
|
|
/* POSIX doesn't guarantee that IOV_MAX is pow of 2 but we're optimistic. */
|
|
size_t bufsz = EXPECTED / IOV_MAX;
|
|
size_t bufrem = EXPECTED % IOV_MAX;
|
|
|
|
/* If there's a remainder then IOV_MAX probably isn't a power of 2 and we
|
|
need to make bufsz bigger so that the last iovec, iv[IOV_MAX-1], is free
|
|
for the remainder. */
|
|
if (bufrem)
|
|
{
|
|
bufsz = bufsz + 1;
|
|
bufrem = EXPECTED - (bufsz * (IOV_MAX - 1));
|
|
}
|
|
|
|
/* We writev to /dev/null since we're just testing writev's return value. */
|
|
int fd = open (_PATH_DEVNULL, O_WRONLY);
|
|
if (fd == -1)
|
|
{
|
|
printf ("Unable to open /dev/null for writing.\n");
|
|
return -1;
|
|
}
|
|
|
|
iv[0].iov_base = malloc (bufsz);
|
|
if (iv[0].iov_base == NULL)
|
|
{
|
|
printf ("malloc (%zu) failed.\n", bufsz);
|
|
close (fd);
|
|
return -1;
|
|
}
|
|
iv[0].iov_len = bufsz;
|
|
|
|
/* We optimistically presume that there isn't a remainder and set all iovec
|
|
instances to the same base and len as the first instance. */
|
|
for (int i = 1; i < IOV_MAX; i++)
|
|
{
|
|
/* We don't care what the data is so reuse the allocation from iv[0]; */
|
|
iv[i].iov_base = iv[0].iov_base;
|
|
iv[i].iov_len = iv[0].iov_len;
|
|
}
|
|
|
|
/* If there is a remainder then we correct the last iov_len. */
|
|
if (bufrem)
|
|
iv[IOV_MAX - 1].iov_len = bufrem;
|
|
|
|
/* Write junk to /dev/null with the writev syscall in order to get a return
|
|
of INT32_MAX+1 bytes to verify that the INTERNAL_SYSCALL wrappers aren't
|
|
mangling the result if the signbit of a 32-bit number is set. */
|
|
ssize_t ret = writev (fd, iv, IOV_MAX);
|
|
|
|
free (iv[0].iov_base);
|
|
close (fd);
|
|
|
|
if (ret != (ssize_t) EXPECTED)
|
|
{
|
|
#ifdef ARTIFICIAL_LIMIT
|
|
if (ret != (ssize_t) ARTIFICIAL_LIMIT)
|
|
#endif
|
|
{
|
|
printf ("writev() return value: %zd != EXPECTED: %zd\n",
|
|
ret, EXPECTED);
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
#define TEST_FUNCTION do_test ()
|
|
#include "../test-skeleton.c"
|