diff options
Diffstat (limited to 'usr.bin/random/random.c')
| -rw-r--r-- | usr.bin/random/random.c | 45 |
1 files changed, 24 insertions, 21 deletions
diff --git a/usr.bin/random/random.c b/usr.bin/random/random.c index 9f78a2711cc9..b3b349cbb75a 100644 --- a/usr.bin/random/random.c +++ b/usr.bin/random/random.c @@ -51,6 +51,7 @@ __FBSDID("$FreeBSD$"); #include <fcntl.h> #include <limits.h> #include <locale.h> +#include <stdbool.h> #include <stdint.h> #include <stdio.h> #include <stdlib.h> @@ -67,11 +68,12 @@ main(int argc, char *argv[]) { double denom; int ch, fd, random_exit, randomize_lines, random_type, ret, - selected, unique_output, unbuffer_output; + unique_output, unbuffer_output; + bool selected; char *ep; const char *filename; - denom = 0; + denom = 0.; filename = "/dev/fd/0"; random_type = RANDOM_TYPE_UNSET; random_exit = randomize_lines = unbuffer_output = 0; @@ -119,16 +121,16 @@ main(int argc, char *argv[]) switch (argc) { case 0: - denom = (randomize_lines ? 1 : 2); + 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') + if (denom < 1. || *ep != '\0') errx(1, "denominator is not valid."); - if (random_exit && denom > 256) + if (random_exit && denom > 256.) errx(1, "denominator must be <= 256 for random exit."); break; default: @@ -160,24 +162,25 @@ main(int argc, char *argv[]) return (arc4random_uniform(denom)); /* - * 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. + * Filter stdin, selecting lines with probability 1/denom, one + * character at a time. */ - selected = (arc4random_uniform(denom) == 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 = (arc4random_uniform(denom) == 0); + do { + selected = random_uniform_denom(denom); + if (selected) { + while ((ch = getchar()) != EOF) { + putchar(ch); + if (ch == '\n') + break; + } + } else { + while ((ch = getchar()) != EOF) + if (ch == '\n') + break; } - } + if (ferror(stdout)) + err(2, "stdout"); + } while (ch != EOF); if (ferror(stdin)) err(2, "stdin"); exit (0); |