1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 
  22 /*
  23  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26 
  27 /*
  28  * Copyright (c) 2012 by Delphix. All rights reserved.
  29  */
  30 
  31 #include "../file_common.h"
  32 
  33 /*
  34  * Create a file with assigned size and then free the specified
  35  * section of the file
  36  */
  37 
  38 static void usage(char *progname);
  39 
  40 static void
  41 usage(char *progname)
  42 {
  43         (void) fprintf(stderr,
  44             "usage: %s [-l filesize] [-s start-offset]"
  45             "[-n section-len] filename\n", progname);
  46         exit(1);
  47 }
  48 
  49 int
  50 main(int argc, char *argv[])
  51 {
  52         char *filename = NULL;
  53         char *buf;
  54         size_t filesize = 0;
  55         off_t start_off = 0;
  56         off_t off_len = 0;
  57         int  fd, ch;
  58         struct flock fl;
  59         mode_t mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH;
  60 
  61         while ((ch = getopt(argc, argv, "l:s:n:")) != EOF) {
  62                 switch (ch) {
  63                 case 'l':
  64                         filesize = atoll(optarg);
  65                         break;
  66                 case 's':
  67                         start_off = atoll(optarg);
  68                         break;
  69                 case 'n':
  70                         off_len = atoll(optarg);
  71                         break;
  72                 default:
  73                         usage(argv[0]);
  74                         break;
  75                 }
  76         }
  77 
  78         if (optind == argc - 1)
  79                 filename = argv[optind];
  80         else
  81                 usage(argv[0]);
  82 
  83         buf = (char *)malloc(filesize);
  84 
  85         if ((fd = open(filename, O_RDWR | O_CREAT | O_TRUNC, mode)) < 0) {
  86                 perror("open");
  87                 return (1);
  88         }
  89         if (write(fd, buf, filesize) < filesize) {
  90                 perror("write");
  91                 return (1);
  92         }
  93         fl.l_whence = SEEK_SET;
  94         fl.l_start = start_off;
  95         fl.l_len = off_len;
  96         if (fcntl(fd, F_FREESP, &fl) != 0) {
  97                 perror("fcntl");
  98                 return (1);
  99         }
 100 
 101         free(buf);
 102         return (0);
 103 }