1 /*- 2 * Copyright (c) 2000 Sheldon Hearn <sheldonh@FreeBSD.org>. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 */ 27 28 #ifndef lint 29 static const char rcsid[] = 30 "$FreeBSD$"; 31 #endif 32 33 #include <sys/stat.h> 34 35 #include <ctype.h> 36 #include <err.h> 37 #include <errno.h> 38 #include <fcntl.h> 39 #include <stdio.h> 40 #include <stdlib.h> 41 #include <unistd.h> 42 43 #include <libutil.h> 44 45 static void usage(void); 46 47 static int no_create; 48 static int do_relative; 49 static int do_refer; 50 static int got_size; 51 52 int 53 main(int argc, char **argv) 54 { 55 struct stat sb; 56 mode_t omode; 57 off_t oflow, rsize, sz, tsize; 58 uint64_t usz; 59 int ch, error, fd, oflags; 60 char *fname, *rname; 61 62 fd = -1; 63 rsize = tsize = sz = 0; 64 error = 0; 65 rname = NULL; 66 while ((ch = getopt(argc, argv, "cr:s:")) != -1) 67 switch (ch) { 68 case 'c': 69 no_create = 1; 70 break; 71 case 'r': 72 do_refer = 1; 73 rname = optarg; 74 break; 75 case 's': 76 do_relative = *optarg == '+' || *optarg == '-'; 77 if (expand_number(do_relative ? optarg + 1 : optarg, 78 &usz) == -1 || (off_t)usz < 0) 79 errx(EXIT_FAILURE, 80 "invalid size argument `%s'", optarg); 81 82 sz = (*optarg == '-') ? -(off_t)usz : (off_t)usz; 83 got_size = 1; 84 break; 85 default: 86 usage(); 87 /* NOTREACHED */ 88 } 89 90 argv += optind; 91 argc -= optind; 92 93 /* 94 * Exactly one of do_refer or got_size must be specified. Since 95 * do_relative implies got_size, do_relative and do_refer are 96 * also mutually exclusive. See usage() for allowed invocations. 97 */ 98 if (do_refer + got_size != 1 || argc < 1) 99 usage(); 100 if (do_refer) { 101 if (stat(rname, &sb) == -1) 102 err(EXIT_FAILURE, "%s", rname); 103 tsize = sb.st_size; 104 } else if (do_relative) 105 rsize = sz; 106 else 107 tsize = sz; 108 109 if (no_create) 110 oflags = O_WRONLY; 111 else 112 oflags = O_WRONLY | O_CREAT; 113 omode = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH; 114 115 while ((fname = *argv++) != NULL) { 116 if (fd != -1) 117 close(fd); 118 if ((fd = open(fname, oflags, omode)) == -1) { 119 if (errno != ENOENT) { 120 warn("%s", fname); 121 error++; 122 } 123 continue; 124 } 125 if (do_relative) { 126 if (fstat(fd, &sb) == -1) { 127 warn("%s", fname); 128 error++; 129 continue; 130 } 131 oflow = sb.st_size + rsize; 132 if (oflow < (sb.st_size + rsize)) { 133 errno = EFBIG; 134 warn("%s", fname); 135 error++; 136 continue; 137 } 138 tsize = oflow; 139 } 140 if (tsize < 0) 141 tsize = 0; 142 143 if (ftruncate(fd, tsize) == -1) { 144 warn("%s", fname); 145 error++; 146 continue; 147 } 148 } 149 if (fd != -1) 150 close(fd); 151 152 return error ? EXIT_FAILURE : EXIT_SUCCESS; 153 } 154 155 static void 156 usage(void) 157 { 158 fprintf(stderr, "%s\n%s\n", 159 "usage: truncate [-c] -s [+|-]size[K|k|M|m|G|g|T|t] file ...", 160 " truncate [-c] -r rfile file ..."); 161 exit(EXIT_FAILURE); 162 } 163