Hi all, There are few places that uses php_rand() currently.
https://bugs.php.net/bug.php?id=66718 http://lxr.php.net/search?q=php_rand&defs=&refs=&path=&hist=&project=PHP_5_5 These functions could use php_mt_rand() instead of php_rand(). php_rand() uses several rand functions 62PHPAPI long php_rand(TSRMLS_D) 63{ 64 long ret; 65 66 if (!BG(rand_is_seeded)) { 67 php_srand(GENERATE_SEED() TSRMLS_CC); 68 } 69 70#ifdef ZTS 71 ret = php_rand_r(&BG(rand_seed)); 72#else 73# if defined(HAVE_RANDOM) 74 ret = random(); 75# elif defined(HAVE_LRAND48) 76 ret = lrand48(); 77# else 78 ret = rand(); 79# endif 80#endif 81 82 return ret; 83} Most systems use random() which has cycle of 16 * ((2^31) - 1), while MT rand has 2^19937-1. php_mt_rand() could be used where php_rand() is used. Unlike php_rand(), php_mt_rand() does not check if it is seeded or not. It should be changed to check seed status. The only BC issue I can think of is game that expects the same pseudo random sequences. These apps may use mt_srand() to get fixed random sequences and adjust their apps if it is needed. This is acceptable BC for new releases. IMO. It would be good idea to support 64bit version of MT on 64bit platforms, too. http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/emt64.html Any comments? -- Yasuo Ohgaki yohg...@ohgaki.net
