221 lines
7.0 KiB
C
221 lines
7.0 KiB
C
// Copyright (c) 2016 Paul Sokolovsky
|
|
// SPDX-FileCopyrightText: 2014 MicroPython & CircuitPython contributors (https://github.com/adafruit/circuitpython/graphs/contributors)
|
|
//
|
|
// SPDX-License-Identifier: MIT
|
|
|
|
#include <assert.h>
|
|
#include <string.h>
|
|
|
|
#include "py/runtime.h"
|
|
|
|
#if MICROPY_PY_URANDOM
|
|
|
|
// Yasmarang random number generator
|
|
// by Ilya Levin
|
|
// http://www.literatecode.com/yasmarang
|
|
// Public Domain
|
|
|
|
#if !MICROPY_ENABLE_DYNRUNTIME
|
|
STATIC uint32_t yasmarang_pad = 0xeda4baba, yasmarang_n = 69, yasmarang_d = 233;
|
|
STATIC uint8_t yasmarang_dat = 0;
|
|
#endif
|
|
|
|
STATIC uint32_t yasmarang(void) {
|
|
yasmarang_pad += yasmarang_dat + yasmarang_d * yasmarang_n;
|
|
yasmarang_pad = (yasmarang_pad << 3) + (yasmarang_pad >> 29);
|
|
yasmarang_n = yasmarang_pad | 2;
|
|
yasmarang_d ^= (yasmarang_pad << 31) + (yasmarang_pad >> 1);
|
|
yasmarang_dat ^= (char)yasmarang_pad ^ (yasmarang_d >> 8) ^ 1;
|
|
|
|
return yasmarang_pad ^ (yasmarang_d << 5) ^ (yasmarang_pad >> 18) ^ (yasmarang_dat << 1);
|
|
} /* yasmarang */
|
|
|
|
// End of Yasmarang
|
|
|
|
#if MICROPY_PY_URANDOM_EXTRA_FUNCS
|
|
|
|
// returns an unsigned integer below the given argument
|
|
// n must not be zero
|
|
STATIC uint32_t yasmarang_randbelow(uint32_t n) {
|
|
uint32_t mask = 1;
|
|
while ((n & mask) < n) {
|
|
mask = (mask << 1) | 1;
|
|
}
|
|
uint32_t r;
|
|
do {
|
|
r = yasmarang() & mask;
|
|
} while (r >= n);
|
|
return r;
|
|
}
|
|
|
|
#endif
|
|
|
|
STATIC mp_obj_t mod_urandom_getrandbits(mp_obj_t num_in) {
|
|
int n = mp_obj_get_int(num_in);
|
|
if (n > 32 || n == 0) {
|
|
mp_raise_ValueError(NULL);
|
|
}
|
|
uint32_t mask = ~0;
|
|
// Beware of C undefined behavior when shifting by >= than bit size
|
|
mask >>= (32 - n);
|
|
return mp_obj_new_int_from_uint(yasmarang() & mask);
|
|
}
|
|
STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_urandom_getrandbits_obj, mod_urandom_getrandbits);
|
|
|
|
STATIC mp_obj_t mod_urandom_seed(mp_obj_t seed_in) {
|
|
mp_uint_t seed = mp_obj_get_int_truncated(seed_in);
|
|
yasmarang_pad = seed;
|
|
yasmarang_n = 69;
|
|
yasmarang_d = 233;
|
|
yasmarang_dat = 0;
|
|
return mp_const_none;
|
|
}
|
|
STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_urandom_seed_obj, mod_urandom_seed);
|
|
|
|
#if MICROPY_PY_URANDOM_EXTRA_FUNCS
|
|
|
|
STATIC mp_obj_t mod_urandom_randrange(size_t n_args, const mp_obj_t *args) {
|
|
mp_int_t start = mp_obj_get_int(args[0]);
|
|
if (n_args == 1) {
|
|
// range(stop)
|
|
if (start > 0) {
|
|
return mp_obj_new_int(yasmarang_randbelow(start));
|
|
} else {
|
|
goto error;
|
|
}
|
|
} else {
|
|
mp_int_t stop = mp_obj_get_int(args[1]);
|
|
if (n_args == 2) {
|
|
// range(start, stop)
|
|
if (start < stop) {
|
|
return mp_obj_new_int(start + yasmarang_randbelow(stop - start));
|
|
} else {
|
|
goto error;
|
|
}
|
|
} else {
|
|
// range(start, stop, step)
|
|
mp_int_t step = mp_obj_get_int(args[2]);
|
|
mp_int_t n;
|
|
if (step > 0) {
|
|
n = (stop - start + step - 1) / step;
|
|
} else if (step < 0) {
|
|
n = (stop - start + step + 1) / step;
|
|
} else {
|
|
goto error;
|
|
}
|
|
if (n > 0) {
|
|
return mp_obj_new_int(start + step * yasmarang_randbelow(n));
|
|
} else {
|
|
goto error;
|
|
}
|
|
}
|
|
}
|
|
|
|
error:
|
|
mp_raise_ValueError(NULL);
|
|
}
|
|
STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mod_urandom_randrange_obj, 1, 3, mod_urandom_randrange);
|
|
|
|
STATIC mp_obj_t mod_urandom_randint(mp_obj_t a_in, mp_obj_t b_in) {
|
|
mp_int_t a = mp_obj_get_int(a_in);
|
|
mp_int_t b = mp_obj_get_int(b_in);
|
|
if (a <= b) {
|
|
return mp_obj_new_int(a + yasmarang_randbelow(b - a + 1));
|
|
} else {
|
|
mp_raise_ValueError(NULL);
|
|
}
|
|
}
|
|
STATIC MP_DEFINE_CONST_FUN_OBJ_2(mod_urandom_randint_obj, mod_urandom_randint);
|
|
|
|
STATIC mp_obj_t mod_urandom_choice(mp_obj_t seq) {
|
|
mp_int_t len = mp_obj_get_int(mp_obj_len(seq));
|
|
if (len > 0) {
|
|
return mp_obj_subscr(seq, mp_obj_new_int(yasmarang_randbelow(len)), MP_OBJ_SENTINEL);
|
|
} else {
|
|
nlr_raise(mp_obj_new_exception(&mp_type_IndexError));
|
|
}
|
|
}
|
|
STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_urandom_choice_obj, mod_urandom_choice);
|
|
|
|
#if MICROPY_PY_BUILTINS_FLOAT
|
|
|
|
// returns a number in the range [0..1) using Yasmarang to fill in the fraction bits
|
|
STATIC mp_float_t yasmarang_float(void) {
|
|
#if MICROPY_FLOAT_IMPL == MICROPY_FLOAT_IMPL_DOUBLE
|
|
typedef uint64_t mp_float_int_t;
|
|
#elif MICROPY_FLOAT_IMPL == MICROPY_FLOAT_IMPL_FLOAT
|
|
typedef uint32_t mp_float_int_t;
|
|
#endif
|
|
union {
|
|
mp_float_t f;
|
|
#if MP_ENDIANNESS_LITTLE
|
|
struct { mp_float_int_t frc : MP_FLOAT_FRAC_BITS, exp : MP_FLOAT_EXP_BITS, sgn : 1;
|
|
} p;
|
|
#else
|
|
struct { mp_float_int_t sgn : 1, exp : MP_FLOAT_EXP_BITS, frc : MP_FLOAT_FRAC_BITS;
|
|
} p;
|
|
#endif
|
|
} u;
|
|
u.p.sgn = 0;
|
|
u.p.exp = (1 << (MP_FLOAT_EXP_BITS - 1)) - 1;
|
|
if (MP_FLOAT_FRAC_BITS <= 32) {
|
|
u.p.frc = yasmarang();
|
|
} else {
|
|
u.p.frc = ((uint64_t)yasmarang() << 32) | (uint64_t)yasmarang();
|
|
}
|
|
return u.f - 1;
|
|
}
|
|
|
|
STATIC mp_obj_t mod_urandom_random(void) {
|
|
return mp_obj_new_float(yasmarang_float());
|
|
}
|
|
STATIC MP_DEFINE_CONST_FUN_OBJ_0(mod_urandom_random_obj, mod_urandom_random);
|
|
|
|
STATIC mp_obj_t mod_urandom_uniform(mp_obj_t a_in, mp_obj_t b_in) {
|
|
mp_float_t a = mp_obj_get_float(a_in);
|
|
mp_float_t b = mp_obj_get_float(b_in);
|
|
return mp_obj_new_float(a + (b - a) * yasmarang_float());
|
|
}
|
|
STATIC MP_DEFINE_CONST_FUN_OBJ_2(mod_urandom_uniform_obj, mod_urandom_uniform);
|
|
|
|
#endif
|
|
|
|
#endif // MICROPY_PY_URANDOM_EXTRA_FUNCS
|
|
|
|
#ifdef MICROPY_PY_URANDOM_SEED_INIT_FUNC
|
|
STATIC mp_obj_t mod_urandom___init__() {
|
|
mod_urandom_seed(MP_OBJ_NEW_SMALL_INT(MICROPY_PY_URANDOM_SEED_INIT_FUNC));
|
|
return mp_const_none;
|
|
}
|
|
STATIC MP_DEFINE_CONST_FUN_OBJ_0(mod_urandom___init___obj, mod_urandom___init__);
|
|
#endif
|
|
|
|
#if !MICROPY_ENABLE_DYNRUNTIME
|
|
STATIC const mp_rom_map_elem_t mp_module_urandom_globals_table[] = {
|
|
{ MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_urandom) },
|
|
#ifdef MICROPY_PY_URANDOM_SEED_INIT_FUNC
|
|
{ MP_ROM_QSTR(MP_QSTR___init__), MP_ROM_PTR(&mod_urandom___init___obj) },
|
|
#endif
|
|
{ MP_ROM_QSTR(MP_QSTR_getrandbits), MP_ROM_PTR(&mod_urandom_getrandbits_obj) },
|
|
{ MP_ROM_QSTR(MP_QSTR_seed), MP_ROM_PTR(&mod_urandom_seed_obj) },
|
|
#if MICROPY_PY_URANDOM_EXTRA_FUNCS
|
|
{ MP_ROM_QSTR(MP_QSTR_randrange), MP_ROM_PTR(&mod_urandom_randrange_obj) },
|
|
{ MP_ROM_QSTR(MP_QSTR_randint), MP_ROM_PTR(&mod_urandom_randint_obj) },
|
|
{ MP_ROM_QSTR(MP_QSTR_choice), MP_ROM_PTR(&mod_urandom_choice_obj) },
|
|
#if MICROPY_PY_BUILTINS_FLOAT
|
|
{ MP_ROM_QSTR(MP_QSTR_random), MP_ROM_PTR(&mod_urandom_random_obj) },
|
|
{ MP_ROM_QSTR(MP_QSTR_uniform), MP_ROM_PTR(&mod_urandom_uniform_obj) },
|
|
#endif
|
|
#endif
|
|
};
|
|
|
|
STATIC MP_DEFINE_CONST_DICT(mp_module_urandom_globals, mp_module_urandom_globals_table);
|
|
|
|
const mp_obj_module_t mp_module_urandom = {
|
|
.base = { &mp_type_module },
|
|
.globals = (mp_obj_dict_t *)&mp_module_urandom_globals,
|
|
};
|
|
#endif
|
|
|
|
#endif // MICROPY_PY_URANDOM
|