1 /*-
2 * Copyright (c) 2001-2013
3 * HATANO Tomomi. 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 #include <stdio.h>
29 #include <stdlib.h>
30 #include <string.h>
31 #include <strings.h>
32 #include <fcntl.h>
33 #include <limits.h>
34 #include <sys/stat.h>
35 #include <sys/types.h>
36 #include <sys/uio.h>
37 #include <unistd.h>
38 #include <ctype.h>
39 #include <errno.h>
40
41 #define MKFILE_WBUF ((size_t)(1048576)) /* Is 1M a reasonable value? */
42
43 /* SunOS's mkfile(8) sets "sticky bit." */
44 #define MKFILE_FLAG (O_WRONLY | O_CREAT | O_TRUNC)
45 #define MKFILE_MODE (S_IRUSR | S_IWUSR | S_ISVTX)
46
47 static char buf[MKFILE_WBUF];
48 static int nofill = 0;
49 static int verbose = 0;
50
51 static void
usage()52 usage()
53 {
54 fprintf(stderr,
55 "Usage: mkfile [-nv] <size>[e|p|t|g|m|k|b] <filename> ...\n");
56 }
57
58 static unsigned long long
getsize(char * s)59 getsize(char *s)
60 {
61 int sh;
62 unsigned long long length;
63 char *suffix;
64
65 /*
66 * NOTE: We don't handle 'Z' (zetta) or 'Y' (yotta) suffixes yet.
67 * These are too large to store in unsigned long long (64bits).
68 * In the future, we'll have to use larger type,
69 * something like uint128_t.
70 */
71 length = strtoull(s, &suffix, 10);
72 sh = 0;
73 switch (tolower(*suffix)) {
74 case 'e': /* Exabytes. */
75 sh = 60;
76 break;
77 case 'p': /* Petabytes. */
78 sh = 50;
79 break;
80 case 't': /* Terabytes. */
81 sh = 40;
82 break;
83 case 'g': /* Gigabytes. */
84 sh = 30;
85 break;
86 case 'm': /* Megabytes. */
87 sh = 20;
88 break;
89 case 'k': /* Kilobytes. */
90 sh = 10;
91 break;
92 case 'b': /* Blocks. */
93 sh = 9;
94 break;
95 case '\0': /* Bytes. */
96 break;
97 default: /* Unknown... */
98 errno = EINVAL;
99 return 0;
100 }
101 if (sh) {
102 unsigned long long l;
103
104 l = length;
105 length <<= sh;
106 /* Check overflow. */
107 if ((length >> sh) != l) {
108 errno = ERANGE;
109 return 0;
110 }
111 }
112
113 return length;
114 }
115
116 static int
create_file(char * f,unsigned long long s)117 create_file(char *f, unsigned long long s)
118 {
119 int fd;
120 size_t w;
121 ssize_t ws;
122
123 if (verbose) {
124 fprintf(stdout, "%s %llu bytes\n", f, s);
125 fflush(stdout);
126 }
127
128 /* Open file to create. */
129 if ((fd = open(f, MKFILE_FLAG, MKFILE_MODE)) < 0) {
130 return -1;
131 }
132
133 /* Seek to the end and write 1 byte. */
134 if ((lseek(fd, (off_t)(s - 1LL), SEEK_SET) == (off_t)-1) ||
135 (write(fd, buf, (size_t)1) == (ssize_t)-1)) {
136 /*
137 * We don't close(fd) here to avoid overwriting errno.
138 * This is fd-leak, but is not harmful
139 * because returning error causes mkfile(8) to exit.
140 */
141 return -1;
142 }
143
144 /* Fill. */
145 if (!nofill) {
146 if (lseek(fd, (off_t)0, SEEK_SET) == (off_t)-1) {
147 /* Same as above. */
148 return -1;
149 }
150 while (s) {
151 w = (s > MKFILE_WBUF) ? MKFILE_WBUF : s;
152 if ((ws = write(fd, buf, w)) == (ssize_t)-1) {
153 /* Same as above. */
154 return -1;
155 }
156 s -= ws;
157 }
158 }
159 close(fd);
160
161 return 0;
162 }
163
164 int
main(int argc,char * argv[])165 main(int argc, char *argv[])
166 {
167 unsigned long long fsize;
168 int ch;
169
170 /* We have at least 2 arguments. */
171 if (argc < 3) {
172 usage();
173 return EXIT_FAILURE;
174 }
175
176 /* Options. */
177 while ((ch = getopt(argc, argv, "nv")) != -1) {
178 switch (ch) {
179 case 'n':
180 nofill = 1;
181 break;
182 case 'v':
183 verbose = 1;
184 break;
185 default:
186 usage();
187 return EXIT_FAILURE;
188 }
189 }
190 argc -= optind;
191 argv += optind;
192
193 /* File size to create. */
194 if ((fsize = getsize(*argv)) == 0) {
195 perror(*argv);
196 return EXIT_FAILURE;
197 }
198
199 /* Filenames to create. */
200 bzero(buf, MKFILE_WBUF);
201 while (++argv, --argc) {
202 if (create_file(*argv, fsize) == -1) {
203 perror(*argv);
204 return EXIT_FAILURE;
205 }
206 }
207
208 return EXIT_SUCCESS;
209 }
210