tests/lseek.c

/*
 * Copyright (c) 2015-2016 Dmitry V. Levin <ldv@altlinux.org>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "tests.h"
#include <sys/syscall.h>

#ifdef __NR_lseek

# include <stdio.h>
# include <unistd.h>
# include "kernel_types.h"

int
main(void)
{
	const kernel_ulong_t offset = (kernel_ulong_t) 0xfacefeeddeadbeefULL;

	if (sizeof(offset) > sizeof(long)) {
		/*
		 * Cannot use syscall because it takes long arguments.
		 * Let's call lseek with hope it will invoke lseek syscall.
		 */
		long long rc = lseek(-1, offset, SEEK_SET);
		printf("lseek(-1, %lld, SEEK_SET) = %lld %s (%m)\n",
		       (long long) offset, rc, errno2name());
	} else {
		long rc = syscall(__NR_lseek, -1L, offset, SEEK_SET);
		printf("lseek(-1, %ld, SEEK_SET) = %ld %s (%m)\n",
		       (long) offset, rc, errno2name());
	}

	puts("+++ exited with 0 +++");
	return 0;
}

#else

SKIP_MAIN_UNDEFINED("__NR_lseek")

#endif