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1) Replace hardcoded RANDOM_MAX macro with wrong (1 less than must be)

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value with ((double)RAND_MAX + 1)
2) For exit code increase valid denominator upper range from 255 to 256
since returned value is [0 .. denom - 1]
This commit is contained in:
Andrey A. Chernov 2008-08-08 01:02:30 +00:00
parent 941ab616c7
commit 5b6bf07632
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=181409
1 changed files with 5 additions and 11 deletions
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16
games/random/random.c
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@ -63,12 +63,6 @@ __FBSDID("$FreeBSD$");
#include "randomize_fd.h"
/*
* The random() function is defined to return values between 0 and
* 2^31 - 1 inclusive in random(3).
*/
#define RANDOM_MAX 0x7fffffffL
static void usage(void);
int
@ -137,8 +131,8 @@ main(int argc, char *argv[])
err(1, "%s", *argv);
if (denom <= 0 || *ep != '\0')
errx(1, "denominator is not valid.");
if (random_exit && denom > 255)
errx(1, "denominator must be <= 255 for random exit.");
if (random_exit && denom > 256)
errx(1, "denominator must be <= 256 for random exit.");
break;
default:
usage();
@ -168,7 +162,7 @@ main(int argc, char *argv[])
/* Compute a random exit status between 0 and denom - 1. */
if (random_exit)
return (int)((denom * random()) / RANDOM_MAX);
return (int)(denom * random() / ((double)RAND_MAX + 1));
/*
* Select whether to print the first line. (Prime the pump.)
@ -176,7 +170,7 @@ main(int argc, char *argv[])
* 0 (which has a 1 / denom chance of being true), we select the
* line.
*/
selected = (int)(denom * random() / RANDOM_MAX) == 0;
selected = (int)(denom * random() / ((double)RAND_MAX + 1)) == 0;
while ((ch = getchar()) != EOF) {
if (selected)
(void)putchar(ch);
@ -186,7 +180,7 @@ main(int argc, char *argv[])
err(2, "stdout");
/* Now see if the next line is to be printed. */
selected = (int)(denom * random() / RANDOM_MAX) == 0;
selected = (int)(denom * random() / ((double)RAND_MAX + 1)) == 0;
}
}
if (ferror(stdin))