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extmod/modurandom: Add "urandom" module.
Seedable and reproducible pseudo-random number generator. Implemented functions are getrandbits(n) (n <= 32) and seed(). The algorithm used is Yasmarang by Ilya Levin: http://www.literatecode.com/yasmarang
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‎extmod/modurandom.c‎

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/*
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* This file is part of the MicroPython project, http://micropython.org/
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*
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* The MIT License (MIT)
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*
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* Copyright (c) 2016 Paul Sokolovsky
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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#include <assert.h>
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#include <string.h>
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//#include "py/nlr.h"
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#include "py/runtime.h"
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#if MICROPY_PY_URANDOM
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// Yasmarang random number generator
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// by Ilya Levin
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// http://www.literatecode.com/yasmarang
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// Public Domain
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STATIC uint32_t yasmarang_pad = 0xeda4baba, yasmarang_n = 69, yasmarang_d = 233;
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STATIC uint8_t yasmarang_dat = 0;
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uint32_t yasmarang(void)
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{
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yasmarang_pad += yasmarang_dat + yasmarang_d * yasmarang_n;
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yasmarang_pad = (yasmarang_pad<<3) + (yasmarang_pad>>29);
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yasmarang_n = yasmarang_pad | 2;
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yasmarang_d ^= (yasmarang_pad<<31) + (yasmarang_pad>>1);
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yasmarang_dat ^= (char) yasmarang_pad ^ (yasmarang_d>>8) ^ 1;
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return (yasmarang_pad^(yasmarang_d<<5)^(yasmarang_pad>>18)^(yasmarang_dat<<1));
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} /* yasmarang */
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// End of Yasmarang
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STATIC mp_obj_t mod_urandom_getrandbits(mp_obj_t num_in) {
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int n = mp_obj_get_int(num_in);
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if (n > 32 || n == 0) {
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nlr_raise(mp_obj_new_exception(&mp_type_ValueError));
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}
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uint32_t mask = ~0;
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// Beware of C undefined behavior when shifting by >= than bit size
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mask >>= (32 - n);
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return mp_obj_new_int_from_uint(yasmarang() & mask);
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}
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STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_urandom_getrandbits_obj, mod_urandom_getrandbits);
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STATIC mp_obj_t mod_urandom_seed(mp_obj_t seed_in) {
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mp_uint_t seed = mp_obj_get_int_truncated(seed_in);
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yasmarang_pad = seed;
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yasmarang_n = 69;
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yasmarang_d = 233;
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yasmarang_dat = 0;
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return mp_const_none;
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}
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STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_urandom_seed_obj, mod_urandom_seed);
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STATIC const mp_rom_map_elem_t mp_module_urandom_globals_table[] = {
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{ MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_urandom) },
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{ MP_ROM_QSTR(MP_QSTR_getrandbits), MP_ROM_PTR(&mod_urandom_getrandbits_obj) },
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{ MP_ROM_QSTR(MP_QSTR_seed), MP_ROM_PTR(&mod_urandom_seed_obj) },
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};
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STATIC MP_DEFINE_CONST_DICT(mp_module_urandom_globals, mp_module_urandom_globals_table);
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const mp_obj_module_t mp_module_urandom = {
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.base = { &mp_type_module },
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.name = MP_QSTR_urandom,
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.globals = (mp_obj_dict_t*)&mp_module_urandom_globals,
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};
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#endif //MICROPY_PY_URANDOM

‎py/builtin.h‎

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@@ -101,6 +101,7 @@ extern const mp_obj_module_t mp_module_ure;
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extern const mp_obj_module_t mp_module_uheapq;
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extern const mp_obj_module_t mp_module_uhashlib;
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extern const mp_obj_module_t mp_module_ubinascii;
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extern const mp_obj_module_t mp_module_urandom;
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extern const mp_obj_module_t mp_module_ussl;
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extern const mp_obj_module_t mp_module_machine;
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extern const mp_obj_module_t mp_module_lwip;

‎py/mpconfig.h‎

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#define MICROPY_PY_UBINASCII (0)
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#endif
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#ifndef MICROPY_PY_URANDOM
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#define MICROPY_PY_URANDOM (0)
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#endif
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#ifndef MICROPY_PY_MACHINE
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#define MICROPY_PY_MACHINE (0)
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#endif

‎py/objmodule.c‎

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#if MICROPY_PY_UBINASCII
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{ MP_ROM_QSTR(MP_QSTR_ubinascii), MP_ROM_PTR(&mp_module_ubinascii) },
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#endif
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#if MICROPY_PY_URANDOM
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{ MP_ROM_QSTR(MP_QSTR_urandom), MP_ROM_PTR(&mp_module_urandom) },
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#endif
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#if MICROPY_PY_USSL
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{ MP_ROM_QSTR(MP_QSTR_ussl), MP_ROM_PTR(&mp_module_ussl) },
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#endif

‎py/py.mk‎

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../extmod/modubinascii.o \
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../extmod/machine_mem.o \
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../extmod/modussl.o \
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../extmod/modurandom.o \
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../extmod/fsusermount.o \
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../extmod/moduos_dupterm.o \
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‎py/qstrdefs.h‎

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#if MICROPY_PY_OS_DUPTERM
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Q(dupterm)
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#endif
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#if MICROPY_PY_URANDOM
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Q(urandom)
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Q(getrandbits)
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Q(seed)
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#endif

‎stmhal/mpconfigport.h‎

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#define MICROPY_PY_IO (1)
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#define MICROPY_PY_IO_FILEIO (1)
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#define MICROPY_PY_UBINASCII (1)
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#define MICROPY_PY_URANDOM (1)
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#define MICROPY_PY_UCTYPES (1)
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#define MICROPY_PY_UZLIB (1)
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#define MICROPY_PY_UJSON (1)

‎unix/mpconfigport.h‎

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#define MICROPY_PY_UHEAPQ (1)
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#define MICROPY_PY_UHASHLIB (1)
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#define MICROPY_PY_UBINASCII (1)
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#define MICROPY_PY_URANDOM (1)
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#ifndef MICROPY_PY_USELECT
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#define MICROPY_PY_USELECT (1)
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#endif

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