1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2000 Sheldon Hearn <sheldonh@FreeBSD.org>.
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 #ifndef lint
31 static const char rcsid[] =
32 "$FreeBSD$";
33 #endif
34
35 #include <sys/stat.h>
36
37 #include <ctype.h>
38 #include <err.h>
39 #include <errno.h>
40 #include <fcntl.h>
41 #include <stdio.h>
42 #include <stdlib.h>
43 #include <unistd.h>
44
45 #include <libutil.h>
46
47 static void usage(void);
48
49 static int no_create;
50 static int do_relative;
51 static int do_refer;
52 static int got_size;
53
54 int
main(int argc,char ** argv)55 main(int argc, char **argv)
56 {
57 struct stat sb;
58 mode_t omode;
59 off_t oflow, rsize, sz, tsize;
60 uint64_t usz;
61 int ch, error, fd, oflags;
62 char *fname, *rname;
63
64 fd = -1;
65 rsize = tsize = sz = 0;
66 error = 0;
67 rname = NULL;
68 while ((ch = getopt(argc, argv, "cr:s:")) != -1)
69 switch (ch) {
70 case 'c':
71 no_create = 1;
72 break;
73 case 'r':
74 do_refer = 1;
75 rname = optarg;
76 break;
77 case 's':
78 do_relative = *optarg == '+' || *optarg == '-';
79 if (expand_number(do_relative ? optarg + 1 : optarg,
80 &usz) == -1 || (off_t)usz < 0)
81 errx(EXIT_FAILURE,
82 "invalid size argument `%s'", optarg);
83
84 sz = (*optarg == '-') ? -(off_t)usz : (off_t)usz;
85 got_size = 1;
86 break;
87 default:
88 usage();
89 /* NOTREACHED */
90 }
91
92 argv += optind;
93 argc -= optind;
94
95 /*
96 * Exactly one of do_refer or got_size must be specified. Since
97 * do_relative implies got_size, do_relative and do_refer are
98 * also mutually exclusive. See usage() for allowed invocations.
99 */
100 if (do_refer + got_size != 1 || argc < 1)
101 usage();
102 if (do_refer) {
103 if (stat(rname, &sb) == -1)
104 err(EXIT_FAILURE, "%s", rname);
105 tsize = sb.st_size;
106 } else if (do_relative)
107 rsize = sz;
108 else
109 tsize = sz;
110
111 if (no_create)
112 oflags = O_WRONLY;
113 else
114 oflags = O_WRONLY | O_CREAT;
115 omode = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH;
116
117 while ((fname = *argv++) != NULL) {
118 if (fd != -1)
119 close(fd);
120 if ((fd = open(fname, oflags, omode)) == -1) {
121 if (errno != ENOENT) {
122 warn("%s", fname);
123 error++;
124 }
125 continue;
126 }
127 if (do_relative) {
128 if (fstat(fd, &sb) == -1) {
129 warn("%s", fname);
130 error++;
131 continue;
132 }
133 oflow = sb.st_size + rsize;
134 if (oflow < (sb.st_size + rsize)) {
135 errno = EFBIG;
136 warn("%s", fname);
137 error++;
138 continue;
139 }
140 tsize = oflow;
141 }
142 if (tsize < 0)
143 tsize = 0;
144
145 if (ftruncate(fd, tsize) == -1) {
146 warn("%s", fname);
147 error++;
148 continue;
149 }
150 }
151 if (fd != -1)
152 close(fd);
153
154 return error ? EXIT_FAILURE : EXIT_SUCCESS;
155 }
156
157 static void
usage(void)158 usage(void)
159 {
160 fprintf(stderr, "%s\n%s\n",
161 "usage: truncate [-c] -s [+|-]size[K|k|M|m|G|g|T|t] file ...",
162 " truncate [-c] -r rfile file ...");
163 exit(EXIT_FAILURE);
164 }
165