diff options
Diffstat (limited to 'usr.bin/random/random.c')
| -rw-r--r-- | usr.bin/random/random.c | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/usr.bin/random/random.c b/usr.bin/random/random.c new file mode 100644 index 0000000..99f9d90 --- /dev/null +++ b/usr.bin/random/random.c @@ -0,0 +1,194 @@ +/* + * Copyright (c) 1994 + * The Regents of the University of California. All rights reserved. + * + * This code is derived from software contributed to Berkeley by + * Guy Harris at Network Appliance Corp. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#if 0 +#ifndef lint +static const char copyright[] = +"@(#) Copyright (c) 1994\n\ + The Regents of the University of California. All rights reserved.\n"; +#endif /* not lint */ + +#ifndef lint +static const char sccsid[] = "@(#)random.c 8.5 (Berkeley) 4/5/94"; +#endif /* not lint */ +#endif +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <sys/types.h> + +#include <err.h> +#include <errno.h> +#include <fcntl.h> +#include <limits.h> +#include <locale.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <time.h> +#include <unistd.h> + +#include "randomize_fd.h" + +static void usage(void); + +int +main(int argc, char *argv[]) +{ + double denom; + int ch, fd, random_exit, randomize_lines, random_type, ret, + selected, unique_output, unbuffer_output; + char *ep; + const char *filename; + + denom = 0; + filename = "/dev/fd/0"; + random_type = RANDOM_TYPE_UNSET; + random_exit = randomize_lines = unbuffer_output = 0; + unique_output = 1; + + (void)setlocale(LC_CTYPE, ""); + + while ((ch = getopt(argc, argv, "ef:hlruUw")) != -1) + switch (ch) { + case 'e': + random_exit = 1; + break; + case 'f': + randomize_lines = 1; + if (strcmp(optarg, "-") != 0) + filename = optarg; + break; + case 'l': + randomize_lines = 1; + random_type = RANDOM_TYPE_LINES; + break; + case 'r': + unbuffer_output = 1; + break; + case 'u': + randomize_lines = 1; + unique_output = 1; + break; + case 'U': + randomize_lines = 1; + unique_output = 0; + break; + case 'w': + randomize_lines = 1; + random_type = RANDOM_TYPE_WORDS; + break; + default: + case '?': + usage(); + /* NOTREACHED */ + } + + argc -= optind; + argv += optind; + + switch (argc) { + case 0: + denom = (randomize_lines ? 1 : 2); + break; + case 1: + errno = 0; + denom = strtod(*argv, &ep); + if (errno == ERANGE) + err(1, "%s", *argv); + if (denom <= 0 || *ep != '\0') + errx(1, "denominator is not valid."); + if (random_exit && denom > 256) + errx(1, "denominator must be <= 256 for random exit."); + break; + default: + usage(); + /* NOTREACHED */ + } + + srandomdev(); + + /* + * Act as a filter, randomly choosing lines of the standard input + * to write to the standard output. + */ + if (unbuffer_output) + setbuf(stdout, NULL); + + /* + * Act as a filter, randomizing lines read in from a given file + * descriptor and write the output to standard output. + */ + if (randomize_lines) { + if ((fd = open(filename, O_RDONLY, 0)) < 0) + err(1, "%s", filename); + ret = randomize_fd(fd, random_type, unique_output, denom); + if (!random_exit) + return(ret); + } + + /* Compute a random exit status between 0 and denom - 1. */ + if (random_exit) + return (int)(denom * random() / RANDOM_MAX_PLUS1); + + /* + * Select whether to print the first line. (Prime the pump.) + * We find a random number between 0 and denom - 1 and, if it's + * 0 (which has a 1 / denom chance of being true), we select the + * line. + */ + selected = (int)(denom * random() / RANDOM_MAX_PLUS1) == 0; + while ((ch = getchar()) != EOF) { + if (selected) + (void)putchar(ch); + if (ch == '\n') { + /* End of that line. See if we got an error. */ + if (ferror(stdout)) + err(2, "stdout"); + + /* Now see if the next line is to be printed. */ + selected = (int)(denom * random() / + RANDOM_MAX_PLUS1) == 0; + } + } + if (ferror(stdin)) + err(2, "stdin"); + exit (0); +} + +static void +usage(void) +{ + + fprintf(stderr, "usage: random [-elrUuw] [-f filename] [denominator]\n"); + exit(1); +} |
