1 /*
2 * Copyright (c) 1994
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Guy Harris at Network Appliance Corp.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33 #if 0
34 #ifndef lint
35 static const char copyright[] =
36 "@(#) Copyright (c) 1994\n\
37 The Regents of the University of California. All rights reserved.\n";
38 #endif /* not lint */
39
40 #ifndef lint
41 static const char sccsid[] = "@(#)random.c 8.5 (Berkeley) 4/5/94";
42 #endif /* not lint */
43 #endif
44 #include <sys/cdefs.h>
45 #include <sys/types.h>
46
47 #include <err.h>
48 #include <errno.h>
49 #include <fcntl.h>
50 #include <limits.h>
51 #include <locale.h>
52 #include <stdbool.h>
53 #include <stdint.h>
54 #include <stdio.h>
55 #include <stdlib.h>
56 #include <string.h>
57 #include <time.h>
58 #include <unistd.h>
59
60 #include "randomize_fd.h"
61
62 static void usage(void) __dead2;
63
64 int
main(int argc,char * argv[])65 main(int argc, char *argv[])
66 {
67 double denom;
68 int ch, fd, random_exit, randomize_lines, random_type, ret,
69 unique_output, unbuffer_output;
70 bool selected;
71 char *ep;
72 const char *filename;
73
74 denom = 0.;
75 filename = "/dev/fd/0";
76 random_type = RANDOM_TYPE_UNSET;
77 random_exit = randomize_lines = unbuffer_output = 0;
78 unique_output = 1;
79
80 (void)setlocale(LC_CTYPE, "");
81
82 while ((ch = getopt(argc, argv, "ef:hlruUw")) != -1)
83 switch (ch) {
84 case 'e':
85 random_exit = 1;
86 break;
87 case 'f':
88 randomize_lines = 1;
89 if (strcmp(optarg, "-") != 0)
90 filename = optarg;
91 break;
92 case 'l':
93 randomize_lines = 1;
94 random_type = RANDOM_TYPE_LINES;
95 break;
96 case 'r':
97 unbuffer_output = 1;
98 break;
99 case 'u':
100 randomize_lines = 1;
101 unique_output = 1;
102 break;
103 case 'U':
104 randomize_lines = 1;
105 unique_output = 0;
106 break;
107 case 'w':
108 randomize_lines = 1;
109 random_type = RANDOM_TYPE_WORDS;
110 break;
111 default:
112 case '?':
113 usage();
114 /* NOTREACHED */
115 }
116
117 argc -= optind;
118 argv += optind;
119
120 switch (argc) {
121 case 0:
122 denom = (randomize_lines ? 1. : 2.);
123 break;
124 case 1:
125 errno = 0;
126 denom = strtod(*argv, &ep);
127 if (errno == ERANGE)
128 err(1, "%s", *argv);
129 if (denom < 1. || *ep != '\0')
130 errx(1, "denominator is not valid.");
131 if (random_exit && denom > 256.)
132 errx(1, "denominator must be <= 256 for random exit.");
133 break;
134 default:
135 usage();
136 /* NOTREACHED */
137 }
138
139 /*
140 * Act as a filter, randomly choosing lines of the standard input
141 * to write to the standard output.
142 */
143 if (unbuffer_output)
144 setbuf(stdout, NULL);
145
146 /*
147 * Act as a filter, randomizing lines read in from a given file
148 * descriptor and write the output to standard output.
149 */
150 if (randomize_lines) {
151 if ((fd = open(filename, O_RDONLY, 0)) < 0)
152 err(1, "%s", filename);
153 ret = randomize_fd(fd, random_type, unique_output, denom);
154 if (!random_exit)
155 return(ret);
156 }
157
158 /* Compute a random exit status between 0 and denom - 1. */
159 if (random_exit)
160 return (arc4random_uniform(denom));
161
162 /*
163 * Filter stdin, selecting lines with probability 1/denom, one
164 * character at a time.
165 */
166 do {
167 selected = random_uniform_denom(denom);
168 if (selected) {
169 while ((ch = getchar()) != EOF) {
170 putchar(ch);
171 if (ch == '\n')
172 break;
173 }
174 } else {
175 while ((ch = getchar()) != EOF)
176 if (ch == '\n')
177 break;
178 }
179 if (ferror(stdout))
180 err(2, "stdout");
181 } while (ch != EOF);
182 if (ferror(stdin))
183 err(2, "stdin");
184 exit (0);
185 }
186
187 static void
usage(void)188 usage(void)
189 {
190
191 fprintf(stderr, "usage: random [-elrUuw] [-f filename] [denominator]\n");
192 exit(1);
193 }
194