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 __FBSDID("$FreeBSD$"); 46 47 #include <sys/types.h> 48 49 #include <err.h> 50 #include <errno.h> 51 #include <fcntl.h> 52 #include <limits.h> 53 #include <locale.h> 54 #include <stdint.h> 55 #include <stdio.h> 56 #include <stdlib.h> 57 #include <string.h> 58 #include <time.h> 59 #include <unistd.h> 60 61 #include "randomize_fd.h" 62 63 static void usage(void); 64 65 int 66 main(int argc, char *argv[]) 67 { 68 double denom; 69 int ch, fd, random_exit, randomize_lines, random_type, ret, 70 selected, unique_output, unbuffer_output; 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 <= 0 || *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 * Select whether to print the first line. (Prime the pump.) 164 * We find a random number between 0 and denom - 1 and, if it's 165 * 0 (which has a 1 / denom chance of being true), we select the 166 * line. 167 */ 168 selected = (arc4random_uniform(denom) == 0); 169 while ((ch = getchar()) != EOF) { 170 if (selected) 171 (void)putchar(ch); 172 if (ch == '\n') { 173 /* End of that line. See if we got an error. */ 174 if (ferror(stdout)) 175 err(2, "stdout"); 176 177 /* Now see if the next line is to be printed. */ 178 selected = (arc4random_uniform(denom) == 0); 179 } 180 } 181 if (ferror(stdin)) 182 err(2, "stdin"); 183 exit (0); 184 } 185 186 static void 187 usage(void) 188 { 189 190 fprintf(stderr, "usage: random [-elrUuw] [-f filename] [denominator]\n"); 191 exit(1); 192 } 193