Fix GH-10292 make the default value of the first parame of srand() and mt_srand() nullable (#10380)

Co-authored-by: Tim Düsterhus <[email protected]>

Author: kocsismate

NEWS

@@ -76,6 +76,8 @@ PHP                                                                        NEWS
 - Random:
   . Added Randomizer::getBytesFromString(). (Joshua Rüsweg)
   . Added Randomizer::nextFloat(), ::getFloat(), and IntervalBoundary. (timwolla)
+  . Fix GH-10292 (Made the default value of the first param of srand() and
+    mt_srand() nullable). (kocsismate)
 
 - Reflection:
   . Fix GH-9470 (ReflectionMethod constructor should not find private parent

UPGRADING

@@ -88,6 +88,10 @@ PHP 8.3 UPGRADE NOTES
     RFC: https://wiki.php.net/rfc/randomizer_additions
   . Added Randomizer::nextFloat(), ::getFloat(), and IntervalBoundary.
     RFC: https://wiki.php.net/rfc/randomizer_additions
+  . Changed mt_srand() and srand() to not check the number of arguments to
+    determine whether a random seed should be used. Passing null will generate
+    a random seed, 0 will use zero as the seed. The functions are now consistent
+    with Mt19937::__construct().
 
 - Sockets:
   . Added socket_atmark to checks if the socket is OOB marked.

ext/random/random.c

@@ -675,19 +675,20 @@ PHP_FUNCTION(lcg_value)
 PHP_FUNCTION(mt_srand)
 {
 	zend_long seed = 0;
+	bool seed_is_null = true;
 	zend_long mode = MT_RAND_MT19937;
 	php_random_status *status = RANDOM_G(mt19937);
 	php_random_status_state_mt19937 *state = status->state;
 
 	ZEND_PARSE_PARAMETERS_START(0, 2)
 		Z_PARAM_OPTIONAL
-		Z_PARAM_LONG(seed)
+		Z_PARAM_LONG_OR_NULL(seed, seed_is_null)
 		Z_PARAM_LONG(mode)
 	ZEND_PARSE_PARAMETERS_END();
 
 	state->mode = mode;
 
-	if (ZEND_NUM_ARGS() == 0) {
+	if (seed_is_null) {
 		php_random_mt19937_seed_default(status->state);
 	} else {
 		php_random_algo_mt19937.seed(status, (uint64_t) seed);

ext/random/random.stub.php

@@ -16,10 +16,10 @@
 
     function lcg_value(): float {}
 
-    function mt_srand(int $seed = 0, int $mode = MT_RAND_MT19937): void {}
+    function mt_srand(?int $seed = null, int $mode = MT_RAND_MT19937): void {}
 
     /** @alias mt_srand */
-    function srand(int $seed = 0, int $mode = MT_RAND_MT19937): void {}
+    function srand(?int $seed = null, int $mode = MT_RAND_MT19937): void {}
 
     function rand(int $min = UNKNOWN, int $max = UNKNOWN): int {}