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 #endif 41 #include <sys/cdefs.h> 42 #include <sys/types.h> 43 44 #include <err.h> 45 #include <errno.h> 46 #include <fcntl.h> 47 #include <limits.h> 48 #include <locale.h> 49 #include <stdbool.h> 50 #include <stdint.h> 51 #include <stdio.h> 52 #include <stdlib.h> 53 #include <string.h> 54 #include <time.h> 55 #include <unistd.h> 56 57 #include "randomize_fd.h" 58 59 static void usage(void) __dead2; 60 61 int 62 main(int argc, char *argv[]) 63 { 64 double denom; 65 int ch, fd, random_exit, randomize_lines, random_type, ret, 66 unique_output, unbuffer_output; 67 bool selected; 68 char *ep; 69 const char *filename; 70 71 denom = 0.; 72 filename = "/dev/fd/0"; 73 random_type = RANDOM_TYPE_UNSET; 74 random_exit = randomize_lines = unbuffer_output = 0; 75 unique_output = 1; 76 77 (void)setlocale(LC_CTYPE, ""); 78 79 while ((ch = getopt(argc, argv, "ef:hlruUw")) != -1) 80 switch (ch) { 81 case 'e': 82 random_exit = 1; 83 break; 84 case 'f': 85 randomize_lines = 1; 86 if (strcmp(optarg, "-") != 0) 87 filename = optarg; 88 break; 89 case 'l': 90 randomize_lines = 1; 91 random_type = RANDOM_TYPE_LINES; 92 break; 93 case 'r': 94 unbuffer_output = 1; 95 break; 96 case 'u': 97 randomize_lines = 1; 98 unique_output = 1; 99 break; 100 case 'U': 101 randomize_lines = 1; 102 unique_output = 0; 103 break; 104 case 'w': 105 randomize_lines = 1; 106 random_type = RANDOM_TYPE_WORDS; 107 break; 108 default: 109 case '?': 110 usage(); 111 /* NOTREACHED */ 112 } 113 114 argc -= optind; 115 argv += optind; 116 117 switch (argc) { 118 case 0: 119 denom = (randomize_lines ? 1. : 2.); 120 break; 121 case 1: 122 errno = 0; 123 denom = strtod(*argv, &ep); 124 if (errno == ERANGE) 125 err(1, "%s", *argv); 126 if (denom < 1. || *ep != '\0') 127 errx(1, "denominator is not valid."); 128 if (random_exit && denom > 256.) 129 errx(1, "denominator must be <= 256 for random exit."); 130 break; 131 default: 132 usage(); 133 /* NOTREACHED */ 134 } 135 136 /* 137 * Act as a filter, randomly choosing lines of the standard input 138 * to write to the standard output. 139 */ 140 if (unbuffer_output) 141 setbuf(stdout, NULL); 142 143 /* 144 * Act as a filter, randomizing lines read in from a given file 145 * descriptor and write the output to standard output. 146 */ 147 if (randomize_lines) { 148 if ((fd = open(filename, O_RDONLY, 0)) < 0) 149 err(1, "%s", filename); 150 ret = randomize_fd(fd, random_type, unique_output, denom); 151 if (!random_exit) 152 return(ret); 153 } 154 155 /* Compute a random exit status between 0 and denom - 1. */ 156 if (random_exit) 157 return (arc4random_uniform(denom)); 158 159 /* 160 * Filter stdin, selecting lines with probability 1/denom, one 161 * character at a time. 162 */ 163 do { 164 selected = random_uniform_denom(denom); 165 if (selected) { 166 while ((ch = getchar()) != EOF) { 167 putchar(ch); 168 if (ch == '\n') 169 break; 170 } 171 } else { 172 while ((ch = getchar()) != EOF) 173 if (ch == '\n') 174 break; 175 } 176 if (ferror(stdout)) 177 err(2, "stdout"); 178 } while (ch != EOF); 179 if (ferror(stdin)) 180 err(2, "stdin"); 181 exit (0); 182 } 183 184 static void 185 usage(void) 186 { 187 188 fprintf(stderr, "usage: random [-elrUuw] [-f filename] [denominator]\n"); 189 exit(1); 190 } 191