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TimWollaTimWolla
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Add Randomizer::nextFloat() and Randomizer::getFloat() (#9679)
* random: Add Randomizer::nextFloat() * random: Check that doubles are IEEE-754 in Randomizer::nextFloat() * random: Add Randomizer::nextFloat() tests * random: Add Randomizer::getFloat() implementing the y-section algorithm The algorithm is published in: Drawing Random Floating-Point Numbers from an Interval. Frédéric Goualard, ACM Trans. Model. Comput. Simul., 32:3, 2022. https://doi.org/10.1145/3503512 * random: Implement getFloat_gamma() optimization see https://github.com/php/php-src/pull/9679/files#r994668327 * random: Add Random\IntervalBoundary * random: Split the implementation of γ-section into its own file * random: Add tests for Randomizer::getFloat() * random: Fix γ-section for 32-bit systems * random: Replace check for __STDC_IEC_559__ by compile-time check for DBL_MANT_DIG * random: Drop nextFloat_spacing.phpt * random: Optimize Randomizer::getFloat() implementation * random: Reject non-finite parameters in Randomizer::getFloat() * random: Add NEWS/UPGRADING for Randomizer’s float functionality
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‎NEWS

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@@ -60,6 +60,7 @@ PHP NEWS
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- Random:
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. Added Randomizer::getBytesFromString(). (Joshua Rüsweg)
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. Added Randomizer::nextFloat(), ::getFloat(), and IntervalBoundary. (timwolla)
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- Reflection:
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. Fix GH-9470 (ReflectionMethod constructor should not find private parent

‎UPGRADING

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@@ -66,6 +66,8 @@ PHP 8.3 UPGRADE NOTES
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- Random:
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. Added Randomizer::getBytesFromString().
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RFC: https://wiki.php.net/rfc/randomizer_additions
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. Added Randomizer::nextFloat(), ::getFloat(), and IntervalBoundary.
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RFC: https://wiki.php.net/rfc/randomizer_additions
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- Sockets:
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. Added socket_atmark to checks if the socket is OOB marked.

‎ext/random/config.m4

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@@ -25,6 +25,7 @@ PHP_NEW_EXTENSION(random,
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engine_xoshiro256starstar.c \
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engine_secure.c \
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engine_user.c \
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gammasection.c \
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randomizer.c,
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no,, -DZEND_ENABLE_STATIC_TSRMLS_CACHE=1)
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PHP_INSTALL_HEADERS([ext/random], [php_random.h])

‎ext/random/config.w32

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EXTENSION("random", "random.c", false /* never shared */, "/DZEND_ENABLE_STATIC_TSRMLS_CACHE=1");
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PHP_RANDOM="yes";
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ADD_SOURCES(configure_module_dirname, "engine_combinedlcg.c engine_mt19937.c engine_pcgoneseq128xslrr64.c engine_xoshiro256starstar.c engine_secure.c engine_user.c randomizer.c", "random");
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ADD_SOURCES(configure_module_dirname, "engine_combinedlcg.c engine_mt19937.c engine_pcgoneseq128xslrr64.c engine_xoshiro256starstar.c engine_secure.c engine_user.c gammasection.c randomizer.c", "random");
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PHP_INSTALL_HEADERS("ext/random", "php_random.h");

‎ext/random/gammasection.c

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/*
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+----------------------------------------------------------------------+
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| Copyright (c) The PHP Group |
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+----------------------------------------------------------------------+
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| This source file is subject to version 3.01 of the PHP license, |
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| that is bundled with this package in the file LICENSE, and is |
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| available through the world-wide-web at the following url: |
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| https://www.php.net/license/3_01.txt |
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| If you did not receive a copy of the PHP license and are unable to |
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| obtain it through the world-wide-web, please send a note to |
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| license@php.net so we can mail you a copy immediately. |
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+----------------------------------------------------------------------+
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| Authors: Tim Düsterhus <timwolla@php.net> |
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| |
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| Based on code from: Frédéric Goualard |
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+----------------------------------------------------------------------+
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*/
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#ifdef HAVE_CONFIG_H
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# include "config.h"
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#endif
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#include "php.h"
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#include "php_random.h"
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#include <math.h>
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/* This file implements the γ-section algorithm as published in:
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*
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* Drawing Random Floating-Point Numbers from an Interval. Frédéric
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* Goualard, ACM Trans. Model. Comput. Simul., 32:3, 2022.
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* https://doi.org/10.1145/3503512
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*/
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static double gamma_low(double x)
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{
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return x - nextafter(x, -DBL_MAX);
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}
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static double gamma_high(double x)
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{
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return nextafter(x, DBL_MAX) - x;
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}
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static double gamma_max(double x, double y)
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{
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return (fabs(x) > fabs(y)) ? gamma_high(x) : gamma_low(y);
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}
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static uint64_t ceilint(double a, double b, double g)
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{
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double s = b / g - a / g;
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double e;
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if (fabs(a) <= fabs(b)) {
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e = -a / g - (s - b / g);
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} else {
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e = b / g - (s + a / g);
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}
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double si = ceil(s);
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return (s != si) ? (uint64_t)si : (uint64_t)si + (e > 0);
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}
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PHPAPI double php_random_gammasection_closed_open(const php_random_algo *algo, php_random_status *status, double min, double max)
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{
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double g = gamma_max(min, max);
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uint64_t hi = ceilint(min, max, g);
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uint64_t k = 1 + php_random_range64(algo, status, hi - 1); /* [1, hi] */
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if (fabs(min) <= fabs(max)) {
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return k == hi ? min : max - k * g;
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} else {
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return min + (k - 1) * g;
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}
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}
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PHPAPI double php_random_gammasection_closed_closed(const php_random_algo *algo, php_random_status *status, double min, double max)
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{
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double g = gamma_max(min, max);
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uint64_t hi = ceilint(min, max, g);
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uint64_t k = php_random_range64(algo, status, hi); /* [0, hi] */
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if (fabs(min) <= fabs(max)) {
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return k == hi ? min : max - k * g;
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} else {
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return k == hi ? max : min + k * g;
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}
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}
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PHPAPI double php_random_gammasection_open_closed(const php_random_algo *algo, php_random_status *status, double min, double max)
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{
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double g = gamma_max(min, max);
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uint64_t hi = ceilint(min, max, g);
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uint64_t k = php_random_range64(algo, status, hi - 1); /* [0, hi - 1] */
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if (fabs(min) <= fabs(max)) {
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return max - k * g;
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} else {
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return k == (hi - 1) ? max : min + (k + 1) * g;
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}
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}
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PHPAPI double php_random_gammasection_open_open(const php_random_algo *algo, php_random_status *status, double min, double max)
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{
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double g = gamma_max(min, max);
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uint64_t hi = ceilint(min, max, g);
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uint64_t k = 1 + php_random_range64(algo, status, hi - 2); /* [1, hi - 1] */
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if (fabs(min) <= fabs(max)) {
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return max - k * g;
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} else {
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return min + k * g;
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}
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}

‎ext/random/php_random.h

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extern PHPAPI zend_class_entry *random_ce_Random_Engine_Mt19937;
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extern PHPAPI zend_class_entry *random_ce_Random_Engine_Xoshiro256StarStar;
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extern PHPAPI zend_class_entry *random_ce_Random_Engine_Secure;
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extern PHPAPI zend_class_entry *random_ce_Random_Randomizer;
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extern PHPAPI zend_class_entry *random_ce_Random_IntervalBoundary;
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static inline php_random_engine *php_random_engine_from_obj(zend_object *object) {
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return (php_random_engine *)((char *)(object) - XtOffsetOf(php_random_engine, std));
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}
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PHPAPI php_random_engine *php_random_engine_common_init(zend_class_entry *ce, zend_object_handlers *handlers, const php_random_algo *algo);
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PHPAPI void php_random_engine_common_free_object(zend_object *object);
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PHPAPI zend_object *php_random_engine_common_clone_object(zend_object *object);
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PHPAPI uint32_t php_random_range32(const php_random_algo *algo, php_random_status *status, uint32_t umax);
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PHPAPI uint64_t php_random_range64(const php_random_algo *algo, php_random_status *status, uint64_t umax);
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PHPAPI zend_long php_random_range(const php_random_algo *algo, php_random_status *status, zend_long min, zend_long max);
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PHPAPI const php_random_algo *php_random_default_algo(void);
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PHPAPI php_random_status *php_random_default_status(void);
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PHPAPI void php_random_xoshiro256starstar_jump(php_random_status_state_xoshiro256starstar *state);
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PHPAPI void php_random_xoshiro256starstar_jump_long(php_random_status_state_xoshiro256starstar *state);
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PHPAPI double php_random_gammasection_closed_open(const php_random_algo *algo, php_random_status *status, double min, double max);
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PHPAPI double php_random_gammasection_closed_closed(const php_random_algo *algo, php_random_status *status, double min, double max);
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PHPAPI double php_random_gammasection_open_closed(const php_random_algo *algo, php_random_status *status, double min, double max);
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PHPAPI double php_random_gammasection_open_open(const php_random_algo *algo, php_random_status *status, double min, double max);
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extern zend_module_entry random_module_entry;
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# define phpext_random_ptr &random_module_entry
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‎ext/random/random.c

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#include "php.h"
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#include "Zend/zend_enum.h"
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#include "Zend/zend_exceptions.h"
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#include "php_random.h"
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PHPAPI zend_class_entry *random_ce_Random_Randomizer;
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PHPAPI zend_class_entry *random_ce_Random_IntervalBoundary;
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PHPAPI zend_class_entry *random_ce_Random_RandomError;
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PHPAPI zend_class_entry *random_ce_Random_BrokenRandomEngineError;
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PHPAPI zend_class_entry *random_ce_Random_RandomException;
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static zend_object_handlers random_engine_secure_object_handlers;
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static zend_object_handlers random_randomizer_object_handlers;
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static inline uint32_t rand_range32(const php_random_algo *algo, php_random_status *status, uint32_t umax)
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PHPAPI uint32_t php_random_range32(const php_random_algo *algo, php_random_status *status, uint32_t umax)
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{
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uint32_t result, limit;
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size_t total_size = 0;
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return result % umax;
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}
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static inline uint64_t rand_range64(const php_random_algo *algo, php_random_status *status, uint64_t umax)
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PHPAPI uint64_t php_random_range64(const php_random_algo *algo, php_random_status *status, uint64_t umax)
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{
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uint64_t result, limit;
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size_t total_size = 0;
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zend_ulong umax = (zend_ulong) max - (zend_ulong) min;
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if (umax > UINT32_MAX) {
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return (zend_long) (rand_range64(algo, status, umax) + min);
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return (zend_long) (php_random_range64(algo, status, umax) + min);
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}
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return (zend_long) (rand_range32(algo, status, umax) + min);
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return (zend_long) (php_random_range32(algo, status, umax) + min);
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}
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/* }}} */
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random_randomizer_object_handlers.free_obj = randomizer_free_obj;
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random_randomizer_object_handlers.clone_obj = NULL;
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/* Random\IntervalBoundary */
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random_ce_Random_IntervalBoundary = register_class_Random_IntervalBoundary();
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register_random_symbols(module_number);
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return SUCCESS;

‎ext/random/random.stub.php

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public function nextInt(): int {}
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public function nextFloat(): float {}
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public function getFloat(float $min, float $max, IntervalBoundary $boundary = IntervalBoundary::ClosedOpen): float {}
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public function getInt(int $min, int $max): int {}
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public function getBytes(int $length): string {}
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public function __unserialize(array $data): void {}
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}
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enum IntervalBoundary {
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case ClosedOpen;
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case ClosedClosed;
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case OpenClosed;
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case OpenOpen;
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}
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/**
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* @strict-properties
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*/

‎ext/random/random_arginfo.h

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