cmd/file_trunc/file_trunc.c

/*
 * 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 http://www.opensolaris.org/os/licensing.
 * 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 2007 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 * Copyright (c) 2012, 2014 by Delphix. All rights reserved.
 */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <limits.h>
#include <errno.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/fcntl.h>
#include <sys/stat.h>
#include <sys/statvfs.h>
#include <sys/errno.h>
#include <sys/time.h>
#include <sys/ioctl.h>
#include <sys/wait.h>
#include <sys/param.h>
#include <string.h>

#define FSIZE   256*1024*1024
#define BSIZE   512

/* Initialize Globals */
static long fsize = FSIZE;
static size_t   bsize = BSIZE;
static int  count = 0;
static int  rflag = 0;
static int  seed = 0;
static int  vflag = 0;
static int  errflag = 0;
static off_t    offset = 0;
static char *filename = NULL;

static void usage(char *execname);
static void parse_options(int argc, char *argv[]);
static void do_write(int fd);
static void do_trunc(int fd);

static void
usage(char *execname)
{
    (void) fprintf(stderr,
        "usage: %s [-b blocksize] [-c count] [-f filesize]"
        " [-o offset] [-s seed] [-r] [-v] filename\n", execname);
    (void) exit(1);
}

int
main(int argc, char *argv[])
{
    int i;
    int fd = -1;

    parse_options(argc, argv);

    fd = open(filename, O_RDWR|O_CREAT|O_TRUNC, 0666);
    if (fd < 0) {
        perror("open");
        exit(3);
    }

    for (i = 0; count == 0 || i < count; i++) {
        (void) do_write(fd);
        (void) do_trunc(fd);
    }

    (void) close(fd);
    return (0);
}

static void
parse_options(int argc, char *argv[])
{
    int c;

    extern char *optarg;
    extern int optind, optopt;

    count = fsize / bsize;
    seed = time(NULL);
    while ((c = getopt(argc, argv, "b:c:f:o:rs:v")) != -1) {
        switch (c) {
            case 'b':
                bsize = atoi(optarg);
                break;

            case 'c':
                count = atoi(optarg);
                break;

            case 'f':
                fsize = atoi(optarg);
                break;

            case 'o':
                offset = atoi(optarg);
                break;

            case 'r':
                rflag++;
                break;

            case 's':
                seed = atoi(optarg);
                break;

            case 'v':
                vflag++;
                break;

            case ':':
                (void) fprintf(stderr,
                    "Option -%c requires an operand\n", optopt);
                errflag++;
                break;

            case '?':
                (void) fprintf(stderr,
                    "Unrecognized option: -%c\n", optopt);
                errflag++;
                break;
        }

        if (errflag) {
            (void) usage(argv[0]);
        }
    }
    if (argc <= optind) {
        (void) fprintf(stderr,
            "No filename specified\n");
        usage(argv[0]);
    }
    filename = argv[optind];

    if (vflag) {
        (void) fprintf(stderr, "Seed = %d\n", seed);
    }
    srandom(seed);
}

static void
do_write(int fd)
{
    off_t   roffset = 0;
    char    *buf = NULL;
    char    *rbuf = NULL;

    buf = (char *)calloc(1, bsize);
    rbuf = (char *)calloc(1, bsize);
    if (buf == NULL || rbuf == NULL) {
        perror("malloc");
        exit(4);
    }

    roffset = random() % fsize;
    if (lseek64(fd, (offset + roffset), SEEK_SET) < 0) {
        perror("lseek");
        exit(5);
    }

    (void) strcpy(buf, "ZFS Test Suite Truncation Test");
    if (write(fd, buf, bsize) < bsize) {
        perror("write");
        exit(6);
    }

    if (rflag) {
        if (lseek64(fd, (offset + roffset), SEEK_SET) < 0) {
            perror("lseek");
            exit(7);
        }

        if (read(fd, rbuf, bsize) < bsize) {
            perror("read");
            exit(8);
        }

        if (memcmp(buf, rbuf, bsize) != 0) {
            perror("memcmp");
            exit(9);
        }
    }
    if (vflag) {
        (void) fprintf(stderr,
            "Wrote to offset %lld\n", (offset + roffset));
        if (rflag) {
            (void) fprintf(stderr,
                "Read back from offset %lld\n", (offset + roffset));
        }
    }

    (void) free(buf);
    (void) free(rbuf);
}

static void
do_trunc(int fd)
{
    off_t   roffset = 0;

    roffset = random() % fsize;
    if (ftruncate64(fd, (offset + roffset))  < 0) {
        perror("truncate");
        exit(7);
    }

    if (vflag) {
        (void) fprintf(stderr,
            "Truncated at offset %lld\n",
            (offset + roffset));
    }
}