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, tsize; 58 int64_t sz; 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 if (expand_number(optarg, &sz) == -1) 77 errx(EXIT_FAILURE, 78 "invalid size argument `%s'", optarg); 79 if (*optarg == '+' || *optarg == '-') 80 do_relative = 1; 81 got_size = 1; 82 break; 83 default: 84 usage(); 85 /* NOTREACHED */ 86 } 87 88 argv += optind; 89 argc -= optind; 90 91 /* 92 * Exactly one of do_refer or got_size must be specified. Since 93 * do_relative implies got_size, do_relative and do_refer are 94 * also mutually exclusive. See usage() for allowed invocations. 95 */ 96 if (do_refer + got_size != 1 || argc < 1) 97 usage(); 98 if (do_refer) { 99 if (stat(rname, &sb) == -1) 100 err(EXIT_FAILURE, "%s", rname); 101 tsize = sb.st_size; 102 } else if (do_relative) 103 rsize = sz; 104 else 105 tsize = sz; 106 107 if (no_create) 108 oflags = O_WRONLY; 109 else 110 oflags = O_WRONLY | O_CREAT; 111 omode = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH; 112 113 while ((fname = *argv++) != NULL) { 114 if (fd != -1) 115 close(fd); 116 if ((fd = open(fname, oflags, omode)) == -1) { 117 if (errno != ENOENT) { 118 warn("%s", fname); 119 error++; 120 } 121 continue; 122 } 123 if (do_relative) { 124 if (fstat(fd, &sb) == -1) { 125 warn("%s", fname); 126 error++; 127 continue; 128 } 129 oflow = sb.st_size + rsize; 130 if (oflow < (sb.st_size + rsize)) { 131 errno = EFBIG; 132 warn("%s", fname); 133 error++; 134 continue; 135 } 136 tsize = oflow; 137 } 138 if (tsize < 0) 139 tsize = 0; 140 141 if (ftruncate(fd, tsize) == -1) { 142 warn("%s", fname); 143 error++; 144 continue; 145 } 146 } 147 if (fd != -1) 148 close(fd); 149 150 return error ? EXIT_FAILURE : EXIT_SUCCESS; 151 } 152 153 static void 154 usage(void) 155 { 156 fprintf(stderr, "%s\n%s\n", 157 "usage: truncate [-c] -s [+|-]size[K|k|M|m|G|g|T|t] file ...", 158 " truncate [-c] -r rfile file ..."); 159 exit(EXIT_FAILURE); 160 } 161