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 /*
  32  * Copyright (c) 2018, Joyent, Inc.
  33  */
  34 
  35 #include "../file_common.h"
  36 
  37 /*
  38  * Create a file with assigned size and then free the specified
  39  * section of the file
  40  */
  41 
  42 static void usage(char *progname);
  43 
  44 static void
  45 usage(char *progname)
  46 {
  47         (void) fprintf(stderr,
  48             "usage: %s [-l filesize] [-s start-offset]"
  49             "[-n section-len] filename\n", progname);
  50         exit(1);
  51 }
  52 
  53 int
  54 main(int argc, char *argv[])
  55 {
  56         char *filename = NULL;
  57         char *buf;
  58         size_t filesize = 0;
  59         off_t start_off = 0;
  60         off_t off_len = 0;
  61         int  fd, ch;
  62         struct flock fl;
  63         mode_t mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH;
  64 
  65         while ((ch = getopt(argc, argv, "l:s:n:")) != EOF) {
  66                 switch (ch) {
  67                 case 'l':
  68                         filesize = atoll(optarg);
  69                         break;
  70                 case 's':
  71                         start_off = atoll(optarg);
  72                         break;
  73                 case 'n':
  74                         off_len = atoll(optarg);
  75                         break;
  76                 default:
  77                         usage(argv[0]);
  78                         break;
  79                 }
  80         }
  81 
  82         if (optind == argc - 1)
  83                 filename = argv[optind];
  84         else
  85                 usage(argv[0]);
  86 
  87         buf = (char *)malloc(filesize);
  88 
  89         if ((fd = open(filename, O_RDWR | O_CREAT | O_TRUNC, mode)) < 0) {
  90                 perror("open");
  91                 free(buf);
  92                 return (1);
  93         }
  94         if (write(fd, buf, filesize) < filesize) {
  95                 perror("write");
  96                 free(buf);
  97                 return (1);
  98         }
  99         fl.l_whence = SEEK_SET;
 100         fl.l_start = start_off;
 101         fl.l_len = off_len;
 102         if (fcntl(fd, F_FREESP, &fl) != 0) {
 103                 perror("fcntl");
 104                 free(buf);
 105                 return (1);
 106         }
 107 
 108         free(buf);
 109         return (0);
 110 }