math.c

php-4.4.7学习linux时下载的源代码

/*
   +----------------------------------------------------------------------+
   | PHP Version 4                                                        |
   +----------------------------------------------------------------------+
   | Copyright (c) 1997-2007 The PHP Group                                |
   +----------------------------------------------------------------------+
   | This source file is subject to version 3.01 of the PHP license,      |
   | that is bundled with this package in the file LICENSE, and is        |
   | available through the world-wide-web at the following url:           |
   | http://www.php.net/license/3_01.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          |
   | [e-mail] so we can mail you a copy immediately.               |
   +----------------------------------------------------------------------+
   | Authors: Jim Winstead <[e-mail]>                                 |
   |          Stig S鎡her Bakken <[e-mail]>                            |
   |          Zeev Suraski <[e-mail]>                                |
   | PHP 4.0 patches by Thies C. Arntzen <[e-mail]>               |
   +----------------------------------------------------------------------+
*/

/* $Id: math.c,v 1.97.2.13.2.5 2007/01/01 09:46:48 sebastian Exp $ */

#include "php.h"
#include "php_math.h"
#include "zend_multiply.h"

#include <math.h>
#include <float.h>
#include <stdlib.h>

#ifndef M_PI
#define M_PI 3.14159265358979323846
#endif

#ifndef PHP_ROUND_FUZZ
# ifndef PHP_WIN32
#  define PHP_ROUND_FUZZ 0.50000000001
# else
#  define PHP_ROUND_FUZZ 0.5
# endif
#endif

#define PHP_ROUND_WITH_FUZZ(val, places) {			\
	double tmp_val=val, f = pow(10.0, (double) places);	\
	tmp_val *= f;					\
	if (tmp_val >= 0.0) {				\
		tmp_val = floor(tmp_val + PHP_ROUND_FUZZ);	\
	} else {					\
		tmp_val = ceil(tmp_val - PHP_ROUND_FUZZ);	\
	}						\
	tmp_val /= f;					\
	val = !zend_isnan(tmp_val) ? tmp_val : val;	\
}							\

/* {{{ proto int abs(int number)
   Return the absolute value of the number */

PHP_FUNCTION(abs)
{
	zval **value;

	if (ZEND_NUM_ARGS()!=1||zend_get_parameters_ex(1, &value)==FAILURE) {
		WRONG_PARAM_COUNT;
	}

	convert_scalar_to_number_ex(value);

	if (Z_TYPE_PP(value) == IS_DOUBLE) {
		RETURN_DOUBLE(fabs(Z_DVAL_PP(value)));
	} else if (Z_TYPE_PP(value) == IS_LONG) {
		if (Z_LVAL_PP(value) == LONG_MIN) {
			RETURN_DOUBLE(-(double)LONG_MIN);
		} else {
			RETURN_LONG(Z_LVAL_PP(value) < 0 ? -Z_LVAL_PP(value) : Z_LVAL_PP(value));
		}
	}

	RETURN_FALSE;
}

/* }}} */
/* {{{ proto float ceil(float number)
   Returns the next highest integer value of the number */
PHP_FUNCTION(ceil)
{
	zval **value;

	if (ZEND_NUM_ARGS()!=1||zend_get_parameters_ex(1, &value)==FAILURE) {
		WRONG_PARAM_COUNT;
	}

	convert_scalar_to_number_ex(value);

	if (Z_TYPE_PP(value) == IS_DOUBLE) {
		RETURN_DOUBLE(ceil(Z_DVAL_PP(value)));
	} else if (Z_TYPE_PP(value) == IS_LONG) {
		convert_to_double_ex(value);
		RETURN_DOUBLE(Z_DVAL_PP(value));
	}

	RETURN_FALSE;
}

/* }}} */
/* {{{ proto float floor(float number)
   Returns the next lowest integer value from the number */
PHP_FUNCTION(floor)
{
	zval **value;

	if (ZEND_NUM_ARGS()!=1||zend_get_parameters_ex(1, &value)==FAILURE) {
		WRONG_PARAM_COUNT;
	}

	convert_scalar_to_number_ex(value);

	if (Z_TYPE_PP(value) == IS_DOUBLE) {
		RETURN_DOUBLE(floor(Z_DVAL_PP(value)));
	} else if (Z_TYPE_PP(value) == IS_LONG) {
		convert_to_double_ex(value);
		RETURN_DOUBLE(Z_DVAL_PP(value));
	}

	RETURN_FALSE;
}

/* }}} */


/* {{{ proto float round(float number [, int precision])
   Returns the number rounded to specified precision */
PHP_FUNCTION(round)
{
	zval **value, **precision;
	int places = 0;
	double return_val;

	if (ZEND_NUM_ARGS() < 1 || ZEND_NUM_ARGS() > 2 ||
		zend_get_parameters_ex(ZEND_NUM_ARGS(), &value, &precision) == FAILURE) {
		WRONG_PARAM_COUNT;
	}

	if (ZEND_NUM_ARGS() == 2) {
		convert_to_long_ex(precision);
		places = (int) Z_LVAL_PP(precision);
	}

	convert_scalar_to_number_ex(value);

	switch (Z_TYPE_PP(value)) {
		case IS_LONG:
			/* Simple case - long that doesn't need to be rounded. */
			if (places >= 0) {
				RETURN_DOUBLE((double) Z_LVAL_PP(value));
			}
			/* break omitted intentionally */

		case IS_DOUBLE:
			return_val = (Z_TYPE_PP(value) == IS_LONG) ?
							(double)Z_LVAL_PP(value) : Z_DVAL_PP(value);

			PHP_ROUND_WITH_FUZZ(return_val, places);

			RETURN_DOUBLE(return_val);
			break;

		default:
			RETURN_FALSE;
			break;
	}
}
/* }}} */
/* {{{ proto float sin(float number)
   Returns the sine of the number in radians */

PHP_FUNCTION(sin)
{
	zval **num;

	if (ZEND_NUM_ARGS() != 1 || zend_get_parameters_ex(1, &num) == FAILURE) {
		WRONG_PARAM_COUNT;
	}
	convert_to_double_ex(num);
	Z_DVAL_P(return_value) = sin(Z_DVAL_PP(num));
	Z_TYPE_P(return_value) = IS_DOUBLE;
}

/* }}} */
/* {{{ proto float cos(float number)
   Returns the cosine of the number in radians */

PHP_FUNCTION(cos)
{
	zval **num;

	if (ZEND_NUM_ARGS() != 1 || zend_get_parameters_ex(1, &num) == FAILURE) {
		WRONG_PARAM_COUNT;
	}
	convert_to_double_ex(num);
	Z_DVAL_P(return_value) = cos(Z_DVAL_PP(num));
	Z_TYPE_P(return_value) = IS_DOUBLE;
}
/* }}} */
/* {{{ proto float tan(float number)
   Returns the tangent of the number in radians */
PHP_FUNCTION(tan)
{
	zval **num;

	if (ZEND_NUM_ARGS() != 1 || zend_get_parameters_ex(1, &num) == FAILURE) {
		WRONG_PARAM_COUNT;
	}
	convert_to_double_ex(num);
	Z_DVAL_P(return_value) = tan(Z_DVAL_PP(num));
	Z_TYPE_P(return_value) = IS_DOUBLE;
}

/* }}} */
/* {{{ proto float asin(float number)
   Returns the arc sine of the number in radians */

PHP_FUNCTION(asin)
{
	zval **num;

	if (ZEND_NUM_ARGS() != 1 || zend_get_parameters_ex(1, &num) == FAILURE) {
		WRONG_PARAM_COUNT;
	}
	convert_to_double_ex(num);
	Z_DVAL_P(return_value) = asin(Z_DVAL_PP(num));
	Z_TYPE_P(return_value) = IS_DOUBLE;
}

/* }}} */
/* {{{ proto float acos(float number)
   Return the arc cosine of the number in radians */

PHP_FUNCTION(acos)
{
	zval **num;

	if (ZEND_NUM_ARGS() != 1 || zend_get_parameters_ex(1, &num) == FAILURE) {
		WRONG_PARAM_COUNT;
	}
	convert_to_double_ex(num);
	Z_DVAL_P(return_value) = acos(Z_DVAL_PP(num));
	Z_TYPE_P(return_value) = IS_DOUBLE;
}

/* }}} */
/* {{{ proto float atan(float number)
   Returns the arc tangent of the number in radians */

PHP_FUNCTION(atan)
{
	zval **num;

	if (ZEND_NUM_ARGS() != 1 || zend_get_parameters_ex(1, &num) == FAILURE) {
		WRONG_PARAM_COUNT;
	}
	convert_to_double_ex(num);
	Z_DVAL_P(return_value) = atan(Z_DVAL_PP(num));
	Z_TYPE_P(return_value) = IS_DOUBLE;
}

/* }}} */
/* {{{ proto float atan2(float y, float x)
   Returns the arc tangent of y/x, with the resulting quadrant determined by the signs of y and x */

PHP_FUNCTION(atan2)
{
	zval **num1, **num2;

	if (ZEND_NUM_ARGS() != 2 || zend_get_parameters_ex(2, &num1, &num2) == FAILURE) {
		WRONG_PARAM_COUNT;
	}
	convert_to_double_ex(num1);
	convert_to_double_ex(num2);
	Z_DVAL_P(return_value) = atan2(Z_DVAL_PP(num1), Z_DVAL_PP(num2));
	Z_TYPE_P(return_value) = IS_DOUBLE;
}

/* }}} */
/* {{{ proto float sinh(float number)
   Returns the hyperbolic sine of the number, defined as (exp(number) - exp(-number))/2 */

PHP_FUNCTION(sinh)
{
	zval **num;

	if (ZEND_NUM_ARGS() != 1 || zend_get_parameters_ex(1, &num) == FAILURE) {
		WRONG_PARAM_COUNT;
	}
	convert_to_double_ex(num);
	Z_DVAL_P(return_value) = sinh(Z_DVAL_PP(num));
	Z_TYPE_P(return_value) = IS_DOUBLE;
}

/* }}} */
/* {{{ proto float cosh(float number)
   Returns the hyperbolic cosine of the number, defined as (exp(number) + exp(-number))/2 */

PHP_FUNCTION(cosh)
{
	zval **num;

	if (ZEND_NUM_ARGS() != 1 || zend_get_parameters_ex(1, &num) == FAILURE) {
		WRONG_PARAM_COUNT;
	}
	convert_to_double_ex(num);
	Z_DVAL_P(return_value) = cosh(Z_DVAL_PP(num));
	Z_TYPE_P(return_value) = IS_DOUBLE;
}
/* }}} */
/* {{{ proto float tanh(float number)
   Returns the hyperbolic tangent of the number, defined as sinh(number)/cosh(number) */
PHP_FUNCTION(tanh)
{
	zval **num;

	if (ZEND_NUM_ARGS() != 1 || zend_get_parameters_ex(1, &num) == FAILURE) {
		WRONG_PARAM_COUNT;
	}
	convert_to_double_ex(num);
	Z_DVAL_P(return_value) = tanh(Z_DVAL_PP(num));
	Z_TYPE_P(return_value) = IS_DOUBLE;
}

/* }}} */

#ifndef PHP_WIN32
#ifdef HAVE_ASINH
/* {{{ proto float asinh(float number)
   Returns the inverse hyperbolic sine of the number, i.e. the value whose hyperbolic sine is number */
PHP_FUNCTION(asinh)
{
	zval **num;

	if (ZEND_NUM_ARGS() != 1 || zend_get_parameters_ex(1, &num) == FAILURE) {
		WRONG_PARAM_COUNT;
	}
	convert_to_double_ex(num);
	Z_DVAL_P(return_value) = asinh(Z_DVAL_PP(num));
	Z_TYPE_P(return_value) = IS_DOUBLE;
}
/* }}} */
#endif /* HAVE_ASINH */

#ifdef HAVE_ACOSH
/* {{{ proto float acosh(float number)
   Returns the inverse hyperbolic cosine of the number, i.e. the value whose hyperbolic cosine is number */
PHP_FUNCTION(acosh)
{
	zval **num;

	if (ZEND_NUM_ARGS() != 1 || zend_get_parameters_ex(1, &num) == FAILURE) {
		WRONG_PARAM_COUNT;
	}
	convert_to_double_ex(num);
	Z_DVAL_P(return_value) = acosh(Z_DVAL_PP(num));
	Z_TYPE_P(return_value) = IS_DOUBLE;
}
/* }}} */
#endif /* HAVE_ACOSH */

#ifdef HAVE_ATANH
/* {{{ proto float atanh(float number)
   Returns the inverse hyperbolic tangent of the number, i.e. the value whose hyperbolic tangent is number */
PHP_FUNCTION(atanh)
{
	zval **num;

	if (ZEND_NUM_ARGS() != 1 || zend_get_parameters_ex(1, &num) == FAILURE) {
		WRONG_PARAM_COUNT;
	}
	convert_to_double_ex(num);
	Z_DVAL_P(return_value) = atanh(Z_DVAL_PP(num));
	Z_TYPE_P(return_value) = IS_DOUBLE;
}
/* }}} */
#endif /* HAVE_ATANH */
#endif /* ifndf PHP_WIN32 */


/* {{{ proto float pi(void)
   Returns an approximation of pi */
PHP_FUNCTION(pi)
{
	Z_DVAL_P(return_value) = M_PI;
	Z_TYPE_P(return_value) = IS_DOUBLE;
}
/* }}} */


/* {{{ proto bool is_finite(float val)
   Returns whether argument is finite */
PHP_FUNCTION(is_finite)
{
	double dval;


	if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "d", &dval) == FAILURE) {
		return;
	}
	RETURN_BOOL(zend_finite(dval));
}
/* }}} */

/* {{{ proto bool is_infinite(float val)
   Returns whether argument is infinite */
PHP_FUNCTION(is_infinite)
{
	double dval;

	if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "d", &dval) == FAILURE) {
		return;
	}
	RETURN_BOOL(zend_isinf(dval));
}
/* }}} */

/* {{{ proto bool is_nan(float val)
   Returns whether argument is not a number */
PHP_FUNCTION(is_nan)
{
	double dval;

	if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "d", &dval) == FAILURE) {
		return;
	}
	RETURN_BOOL(zend_isnan(dval));
}
/* }}} */

/* {{{ proto number pow(number base, number exponent)
   Returns base raised to the power of exponent. Returns integer result when possible */
PHP_FUNCTION(pow)
{
	zval *zbase, *zexp;

	if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "z/z/", &zbase, &zexp) == FAILURE) {
		return;
	}

	/* make sure we're dealing with numbers */
	convert_scalar_to_number(zbase TSRMLS_CC);
	convert_scalar_to_number(zexp TSRMLS_CC);

	/* if both base and exponent were longs, we'll try to get a long out */
	if (Z_TYPE_P(zbase) == IS_LONG && Z_TYPE_P(zexp) == IS_LONG && Z_LVAL_P(zexp) >= 0) {
		long l1 = 1, l2 = Z_LVAL_P(zbase), i = Z_LVAL_P(zexp);

		if (i == 0) {
			RETURN_LONG(1L);
		} else if (l2 == 0) {
			RETURN_LONG(0);
		}

		/* calculate pow(long,long) in O(log exp) operations, bail if overflow */
		while (i >= 1) {
			int overflow;
			double dval;

			if (i % 2) {
				--i;
				ZEND_SIGNED_MULTIPLY_LONG(l1,l2,l1,dval,overflow);
				if (overflow) RETURN_DOUBLE(dval * pow(l2,i));
			} else {
				i /= 2;
				ZEND_SIGNED_MULTIPLY_LONG(l2,l2,l2,dval,overflow);
				if (overflow) RETURN_DOUBLE((double)l1 * pow(dval,i));
			}
			if (i == 0) {
				RETURN_LONG(l1);
			}
		}
	}
	convert_to_double(zbase);
	convert_to_double(zexp);

	RETURN_DOUBLE( pow(Z_DVAL_P(zbase),Z_DVAL_P(zexp)) );
}
/* }}} */

/* {{{ proto float exp(float number)
   Returns e raised to the power of the number */

PHP_FUNCTION(exp)
{
	zval **num;

	if (ZEND_NUM_ARGS() != 1 || zend_get_parameters_ex(1, &num) == FAILURE) {
		WRONG_PARAM_COUNT;
	}
	convert_to_double_ex(num);
	Z_DVAL_P(return_value) = exp(Z_DVAL_PP(num));
	Z_TYPE_P(return_value) = IS_DOUBLE;
}

/* }}} */


#if !defined(PHP_WIN32) && !defined(NETWARE)
/* {{{ proto float expm1(float number)
   Returns exp(number) - 1, computed in a way that accurate even when the value of number is close to zero */

/*
   WARNING: this function is expermental: it could change its name or
   disappear in the next version of PHP!
*/

PHP_FUNCTION(expm1)
{
	zval **num;

	if (ZEND_NUM_ARGS() != 1 || zend_get_parameters_ex(1, &num) == FAILURE) {
		WRONG_PARAM_COUNT;
	}
	convert_to_double_ex(num);
	Z_DVAL_P(return_value) = expm1(Z_DVAL_PP(num));
	Z_TYPE_P(return_value) = IS_DOUBLE;
}

/* }}} */
/* {{{ proto float log1p(float number)
   Returns log(1 + number), computed in a way that accurate even when the value of number is close to zero */

/*
   WARNING: this function is expermental: it could change its name or
   disappear in the next version of PHP!
*/

PHP_FUNCTION(log1p)
{
#ifdef HAVE_LOG1P
	zval **num;

	if (ZEND_NUM_ARGS() != 1 || zend_get_parameters_ex(1, &num) == FAILURE) {
		WRONG_PARAM_COUNT;
	}
	convert_to_double_ex(num);
	Z_DVAL_P(return_value) = log1p(Z_DVAL_PP(num));
	Z_TYPE_P(return_value) = IS_DOUBLE;
#endif
}

/* }}} */

#endif
/* {{{ proto float log(float number, [float base])
   Returns the natural logarithm of the number, or the base log if base is specified */

PHP_FUNCTION(log)
{
	zval **num, **base;

	switch (ZEND_NUM_ARGS()) {
		case 1:
			if (zend_get_parameters_ex(1, &num) == FAILURE) {
				WRONG_PARAM_COUNT;
			}
			convert_to_double_ex(num);
			RETURN_DOUBLE(log(Z_DVAL_PP(num)));
		case 2:
			if (zend_get_parameters_ex(2, &num, &base) == FAILURE) {
				WRONG_PARAM_COUNT;
			}
			convert_to_double_ex(num);
			convert_to_double_ex(base);

			if (Z_DVAL_PP(base) <= 0.0) {
				php_error_docref(NULL TSRMLS_CC, E_WARNING, "base must be greater than 0");
				RETURN_FALSE;
			}
			RETURN_DOUBLE(log(Z_DVAL_PP(num)) / log(Z_DVAL_PP(base)));
		default:
			WRONG_PARAM_COUNT;
	}
}

/* }}} */
/* {{{ proto float log10(float number)
   Returns the base-10 logarithm of the number */

PHP_FUNCTION(log10)
{
	zval **num;

	if (ZEND_NUM_ARGS() != 1 || zend_get_parameters_ex(1, &num) == FAILURE) {
		WRONG_PARAM_COUNT;
	}
	convert_to_double_ex(num);
	Z_DVAL_P(return_value) = log10(Z_DVAL_PP(num));
	Z_TYPE_P(return_value) = IS_DOUBLE;