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-rw-r--r--lib/libc/stdlib/rand.c57
1 files changed, 13 insertions, 44 deletions
diff --git a/lib/libc/stdlib/rand.c b/lib/libc/stdlib/rand.c
index 4f4aa8d..6125b1a 100644
--- a/lib/libc/stdlib/rand.c
+++ b/lib/libc/stdlib/rand.c
@@ -49,14 +49,6 @@ __FBSDID("$FreeBSD$");
static int
do_rand(unsigned long *ctx)
{
-#ifdef USE_WEAK_SEEDING
-/*
- * Historic implementation compatibility.
- * The random sequences do not vary much with the seed,
- * even with overflowing.
- */
- return ((*ctx = *ctx * 1103515245 + 12345) % ((u_long)RAND_MAX + 1));
-#else /* !USE_WEAK_SEEDING */
/*
* Compute x = (7^5 * x) mod (2^31 - 1)
* without overflowing 31 bits:
@@ -67,64 +59,45 @@ do_rand(unsigned long *ctx)
*/
long hi, lo, x;
- /* Must be in [1, 0x7ffffffe] range at this point. */
- hi = *ctx / 127773;
- lo = *ctx % 127773;
+ /* Transform to [1, 0x7ffffffe] range. */
+ x = (*ctx % 0x7ffffffe) + 1;
+ hi = x / 127773;
+ lo = x % 127773;
x = 16807 * lo - 2836 * hi;
if (x < 0)
x += 0x7fffffff;
- *ctx = x;
/* Transform to [0, 0x7ffffffd] range. */
- return (x - 1);
-#endif /* !USE_WEAK_SEEDING */
+ x--;
+ *ctx = x;
+ return (x);
}
int
-rand_r(unsigned int *ctx)
+rand_r(unsigned *ctx)
{
u_long val;
int r;
-#ifdef USE_WEAK_SEEDING
val = *ctx;
-#else
- /* Transform to [1, 0x7ffffffe] range. */
- val = (*ctx % 0x7ffffffe) + 1;
-#endif
r = do_rand(&val);
-
-#ifdef USE_WEAK_SEEDING
- *ctx = (unsigned int)val;
-#else
- *ctx = (unsigned int)(val - 1);
-#endif
+ *ctx = (unsigned)val;
return (r);
}
-static u_long next =
-#ifdef USE_WEAK_SEEDING
- 1;
-#else
- 2;
-#endif
+static u_long next = 1;
int
-rand()
+rand(void)
{
return (do_rand(&next));
}
void
-srand(seed)
-u_int seed;
+srand(unsigned seed)
{
next = seed;
-#ifndef USE_WEAK_SEEDING
- /* Transform to [1, 0x7ffffffe] range. */
- next = (next % 0x7ffffffe) + 1;
-#endif
}
@@ -136,7 +109,7 @@ u_int seed;
* data from the kernel.
*/
void
-sranddev()
+sranddev(void)
{
int mib[2];
size_t len;
@@ -146,10 +119,6 @@ sranddev()
mib[0] = CTL_KERN;
mib[1] = KERN_ARND;
sysctl(mib, 2, (void *)&next, &len, NULL, 0);
-#ifndef USE_WEAK_SEEDING
- /* Transform to [1, 0x7ffffffe] range. */
- next = (next % 0x7ffffffe) + 1;
-#endif
}
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