зеркало из https://github.com/github/ruby.git
111 строки
2.3 KiB
C
111 строки
2.3 KiB
C
#include "ruby/random.h"
|
|
|
|
static const uint32_t max_seeds = 1024;
|
|
|
|
typedef struct {
|
|
rb_random_t base;
|
|
uint32_t num, idx, *buf;
|
|
} rand_loop_t;
|
|
|
|
RB_RANDOM_INTERFACE_DECLARE_WITH_REAL(loop);
|
|
static const rb_random_interface_t random_loop_if = {
|
|
32,
|
|
RB_RANDOM_INTERFACE_DEFINE_WITH_REAL(loop)
|
|
};
|
|
|
|
static size_t
|
|
random_loop_memsize(const void *ptr)
|
|
{
|
|
const rand_loop_t *r = ptr;
|
|
return sizeof(*r) + r->num * sizeof(r->buf[0]);
|
|
}
|
|
|
|
static rb_random_data_type_t random_loop_type = {
|
|
"random/loop",
|
|
{
|
|
rb_random_mark,
|
|
RUBY_TYPED_DEFAULT_FREE,
|
|
random_loop_memsize,
|
|
},
|
|
RB_RANDOM_PARENT,
|
|
(void *)&random_loop_if,
|
|
RUBY_TYPED_FREE_IMMEDIATELY
|
|
};
|
|
|
|
|
|
static VALUE
|
|
loop_alloc(VALUE klass)
|
|
{
|
|
rand_loop_t *rnd;
|
|
VALUE obj = TypedData_Make_Struct(klass, rand_loop_t, &random_loop_type, rnd);
|
|
rb_random_base_init(&rnd->base);
|
|
return obj;
|
|
}
|
|
|
|
static void
|
|
loop_init(rb_random_t *rnd, const uint32_t *buf, size_t len)
|
|
{
|
|
rand_loop_t *r = (rand_loop_t *)rnd;
|
|
|
|
if (len > max_seeds) len = max_seeds;
|
|
|
|
REALLOC_N(r->buf, uint32_t, len);
|
|
MEMCPY(r->buf, buf, uint32_t, (r->num = (uint32_t)len));
|
|
}
|
|
|
|
static void
|
|
loop_get_bytes(rb_random_t *rnd, void *p, size_t n)
|
|
{
|
|
uint8_t *buf = p;
|
|
while (n > 0) {
|
|
uint32_t x = loop_get_int32(rnd);
|
|
switch (n % 4) {
|
|
case 0:
|
|
*buf++ = (uint8_t)x;
|
|
n--;
|
|
/* FALLTHROUGH */
|
|
case 3:
|
|
*buf++ = (uint8_t)x;
|
|
n--;
|
|
/* FALLTHROUGH */
|
|
case 2:
|
|
*buf++ = (uint8_t)x;
|
|
n--;
|
|
/* FALLTHROUGH */
|
|
case 1:
|
|
*buf++ = (uint8_t)x;
|
|
n--;
|
|
}
|
|
}
|
|
}
|
|
|
|
static uint32_t
|
|
loop_get_int32(rb_random_t *rnd)
|
|
{
|
|
rand_loop_t *r = (rand_loop_t *)rnd;
|
|
if (r->idx < r->num) {
|
|
uint32_t x = r->buf[r->idx++];
|
|
if (r->idx >= r->num) r->idx = 0;
|
|
return x;
|
|
}
|
|
else if (r->num) {
|
|
return r->buf[r->idx = 0];
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static double
|
|
loop_get_real(rb_random_t *rnd, int excl)
|
|
{
|
|
uint32_t a = loop_get_int32(rnd);
|
|
return ldexp(a, -16);
|
|
}
|
|
|
|
void
|
|
Init_random_loop(VALUE mod, VALUE base)
|
|
{
|
|
VALUE c = rb_define_class_under(mod, "Loop", base);
|
|
rb_define_alloc_func(c, loop_alloc);
|
|
RB_RANDOM_DATA_INIT_PARENT(random_loop_type);
|
|
}
|