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// SPDX-License-Identifier: CDDL-1.0
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or https://opensource.org/licenses/CDDL-1.0.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 2021 by Lawrence Livermore National Security, LLC.
*/
#include <unistd.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/mman.h>
#include <sys/sysmacros.h>
#include <errno.h>
#ifdef __linux__
#include <linux/fs.h>
#endif
/* some older uClibc's lack the defines, so we'll manually define them */
#ifdef __UCLIBC__
#ifndef SEEK_DATA
#define SEEK_DATA 3
#endif
#ifndef SEEK_HOLE
#define SEEK_HOLE 4
#endif
#endif
static void
seek_data(int fd, off_t offset, off_t expected)
{
off_t data_offset = lseek(fd, offset, SEEK_DATA);
if (data_offset != expected) {
fprintf(stderr, "lseek(fd, %d, SEEK_DATA) = %d (expected %d)\n",
(int)offset, (int)data_offset, (int)expected);
exit(2);
}
}
static void
seek_hole(int fd, off_t offset, off_t expected)
{
off_t hole_offset = lseek(fd, offset, SEEK_HOLE);
if (hole_offset != expected) {
fprintf(stderr, "lseek(fd, %d, SEEK_HOLE) = %d (expected %d)\n",
(int)offset, (int)hole_offset, (int)expected);
exit(2);
}
}
int
main(int argc, char **argv)
{
char *execname = argv[0];
char *file_path = argv[1];
char *buf = NULL;
int err;
if (argc != 4) {
(void) printf("usage: %s <file name> <file size> "
"<block size>\n", argv[0]);
exit(1);
}
int fd = open(file_path, O_RDWR | O_CREAT, 0666);
if (fd == -1) {
(void) fprintf(stderr, "%s: %s: ", execname, file_path);
perror("open");
exit(2);
}
off_t file_size = atoi(argv[2]);
off_t block_size = atoi(argv[3]);
if (block_size * 2 > file_size) {
(void) fprintf(stderr, "file size must be at least "
"double the block size\n");
exit(2);
}
err = ftruncate(fd, file_size);
if (err == -1) {
perror("ftruncate");
exit(2);
}
if ((buf = mmap(NULL, file_size, PROT_READ | PROT_WRITE,
MAP_SHARED, fd, 0)) == MAP_FAILED) {
perror("mmap");
exit(2);
}
/* Verify the file is sparse and reports no data. */
seek_data(fd, 0, -1);
/* Verify the file is reported as a hole. */
seek_hole(fd, 0, 0);
/* Verify search beyond end of file is an error. */
seek_data(fd, 2 * file_size, -1);
seek_hole(fd, 2 * file_size, -1);
/* Dirty the first byte. */
memset(buf, 'a', 1);
seek_data(fd, 0, 0);
seek_data(fd, block_size, -1);
seek_hole(fd, 0, block_size);
seek_hole(fd, block_size, block_size);
/* Dirty the first half of the file. */
memset(buf, 'b', file_size / 2);
seek_data(fd, 0, 0);
seek_data(fd, block_size, block_size);
seek_hole(fd, 0, P2ROUNDUP(file_size / 2, block_size));
seek_hole(fd, block_size, P2ROUNDUP(file_size / 2, block_size));
/* Dirty the whole file. */
memset(buf, 'c', file_size);
seek_data(fd, 0, 0);
seek_data(fd, file_size * 3 / 4,
P2ROUNDUP(file_size * 3 / 4, block_size));
seek_hole(fd, 0, file_size);
seek_hole(fd, file_size / 2, file_size);
/* Punch a hole (required compression be enabled). */
memset(buf + block_size, 0, block_size);
seek_data(fd, 0, 0);
seek_data(fd, block_size, 2 * block_size);
seek_hole(fd, 0, block_size);
seek_hole(fd, block_size, block_size);
seek_hole(fd, 2 * block_size, file_size);
err = munmap(buf, file_size);
if (err == -1) {
perror("munmap");
exit(2);
}
close(fd);
return (0);
}
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