moved lcg stuff to ext/standard

1 files changed, 98 insertions, 0 deletions

diff --git a/ext/standard/lcg.c b/ext/standard/lcg.c
new file mode 100644
index 0000000000..8fe4950aa0
--- /dev/null
+++ b/ext/standard/lcg.c
@@ -0,0 +1,98 @@
+/* 
+   +----------------------------------------------------------------------+
+   | PHP version 4.0                                                      |
+   +----------------------------------------------------------------------+
+   | Copyright (c) 1997, 1998, 1999 The PHP Group                         |
+   +----------------------------------------------------------------------+
+   | This source file is subject to version 2.0 of the PHP license,       |
+   | that is bundled with this package in the file LICENSE, and is        |
+   | available at through the world-wide-web at                           |
+   | http://www.php.net/license/2_0.txt.                                  |
+   | If you did not receive a copy of the PHP license and are unable to   |
+   | obtain it through the world-wide-web, please send a note to          |
+   | license@php.net so we can mail you a copy immediately.               |
+   +----------------------------------------------------------------------+
+   | Authors: Sascha Schumann <ss@2ns.de>                                 |
+   +----------------------------------------------------------------------+
+ */
+
+#include "php.h"
+#include "php_lcg.h"
+
+#if HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
+#ifdef ZTS
+int lcg_globals_id;
+#else
+static php_lcg_globals lcg_globals;
+#endif
+
+/*
+ * combinedLCG() returns a pseudo random number in the range of (0,1).
+ * The function combines two CGs with periods of 
+ * 2^31 - 85 and 2^31 - 249. The period of this function
+ * is equal to the product of both primes.
+ */
+
+#define MODMULT(a,b,c,m,s) q = s/a;s=b*(s-a*q)-c*q;if(s<0)s+=m
+
+double php_combined_lcg(void)
+{
+	long q;
+	long z;
+	LCGLS_FETCH();
+
+	MODMULT(53668,40014,12211,2147483563L, LCG(s1));
+	MODMULT(52774,40692,3791, 2147483399L, LCG(s2));
+
+	z = LCG(s1) - LCG(s2);
+	if(z < 1) {
+		z += 2147483562;
+	}
+
+	return z * 4.656613e-10;
+}
+
+static void init_globals(LCGLS_D)
+{
+	LCG(s1) = 1;
+#ifdef ZTS
+	LCG(s2) = (long) tsrm_thread_id();
+#else
+	LCG(s2) = (long) getpid();
+#endif
+}
+
+static int php_minit_lcg(INIT_FUNC_ARGS)
+{
+#ifdef ZTS
+	lcg_globals_id = ts_allocate_id(sizeof(php_lcg_globals), init_globals, NULL);
+#else
+	init_globals();
+#endif
+	return SUCCESS;
+}
+
+/* {{{ proto double lcg_value()
+   returns a value from the combined linear congruential generator */
+PHP_FUNCTION(lcg_value)
+{
+	RETURN_DOUBLE(php_combined_lcg());
+}
+/* }}} */
+
+static function_entry lcg_functions[] = {
+	PHP_FE(lcg_value, NULL)
+	{0}
+};
+
+zend_module_entry lcg_module_entry = {
+	"LCG",
+	lcg_functions,
+	php_minit_lcg, NULL,
+	NULL, NULL,
+	NULL,
+	STANDARD_MODULE_PROPERTIES
+};