1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2000 Sheldon Hearn <[email protected]>.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 *
28 */
29
30 static const char rcsid[] =
31 "$FreeBSD$";
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 int
main(int argc,char ** argv)48 main(int argc, char **argv)
49 {
50 struct stat sb;
51 mode_t omode;
52 off_t oflow, rsize, sz, tsize, round;
53 uint64_t usz;
54 int ch, error, fd, oflags;
55 int no_create;
56 int do_relative;
57 int do_round;
58 int do_refer;
59 int got_size;
60 char *fname, *rname;
61
62 fd = -1;
63 rsize = tsize = sz = 0;
64 no_create = do_relative = do_round = do_refer = got_size = 0;
65 error = 0;
66 rname = NULL;
67 while ((ch = getopt(argc, argv, "cr:s:")) != -1)
68 switch (ch) {
69 case 'c':
70 no_create = 1;
71 break;
72 case 'r':
73 do_refer = 1;
74 rname = optarg;
75 break;
76 case 's':
77 if (*optarg == '+' || *optarg == '-') {
78 do_relative = 1;
79 } else if (*optarg == '%' || *optarg == '/') {
80 do_round = 1;
81 }
82 if (expand_number(do_relative || do_round ?
83 optarg + 1 : optarg,
84 &usz) == -1 || (off_t)usz < 0)
85 errx(EXIT_FAILURE,
86 "invalid size argument `%s'", optarg);
87
88 sz = (*optarg == '-' || *optarg == '/') ?
89 -(off_t)usz : (off_t)usz;
90 got_size = 1;
91 break;
92 default:
93 usage();
94 /* NOTREACHED */
95 }
96
97 argv += optind;
98 argc -= optind;
99
100 /*
101 * Exactly one of do_refer or got_size must be specified. Since
102 * do_relative implies got_size, do_relative and do_refer are
103 * also mutually exclusive. See usage() for allowed invocations.
104 */
105 if (do_refer + got_size != 1 || argc < 1)
106 usage();
107 if (do_refer) {
108 if (stat(rname, &sb) == -1)
109 err(EXIT_FAILURE, "%s", rname);
110 tsize = sb.st_size;
111 } else if (do_relative || do_round)
112 rsize = sz;
113 else
114 tsize = sz;
115
116 if (no_create)
117 oflags = O_WRONLY;
118 else
119 oflags = O_WRONLY | O_CREAT;
120 omode = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH;
121
122 while ((fname = *argv++) != NULL) {
123 if (fd != -1)
124 close(fd);
125 if ((fd = open(fname, oflags, omode)) == -1) {
126 if (errno != ENOENT) {
127 warn("%s", fname);
128 error++;
129 }
130 continue;
131 }
132 if (do_relative) {
133 if (fstat(fd, &sb) == -1) {
134 warn("%s", fname);
135 error++;
136 continue;
137 }
138 oflow = sb.st_size + rsize;
139 if (oflow < (sb.st_size + rsize)) {
140 errno = EFBIG;
141 warn("%s", fname);
142 error++;
143 continue;
144 }
145 tsize = oflow;
146 }
147 if (do_round) {
148 if (fstat(fd, &sb) == -1) {
149 warn("%s", fname);
150 error++;
151 continue;
152 }
153 sz = rsize;
154 if (sz < 0)
155 sz = -sz;
156 if (sb.st_size % sz) {
157 round = sb.st_size / sz;
158 if (round != sz && rsize < 0)
159 round--;
160 else if (rsize > 0)
161 round++;
162 tsize = (round < 0 ? 0 : round) * sz;
163 } else
164 tsize = sb.st_size;
165 }
166 if (tsize < 0)
167 tsize = 0;
168
169 if (ftruncate(fd, tsize) == -1) {
170 warn("%s", fname);
171 error++;
172 continue;
173 }
174 }
175 if (fd != -1)
176 close(fd);
177
178 return error ? EXIT_FAILURE : EXIT_SUCCESS;
179 }
180
181 static void
usage(void)182 usage(void)
183 {
184 fprintf(stderr, "%s\n%s\n",
185 "usage: truncate [-c] -s [+|-|%|/]size[K|k|M|m|G|g|T|t] file ...",
186 " truncate [-c] -r rfile file ...");
187 exit(EXIT_FAILURE);
188 }
189