php-src/Zend/zend_operators.c

/*
   +----------------------------------------------------------------------+
   | Zend Engine                                                          |
   +----------------------------------------------------------------------+
   | Copyright (c) 1998, 1999 Andi Gutmans, Zeev Suraski                  |
   +----------------------------------------------------------------------+
   | This source file is subject to version 0.91 of the Zend license,     |
   | that is bundled with this package in the file LICENSE, and is        | 
   | available at through the world-wide-web at                           |
   | http://www.zend.com/license/0_91.txt.                                |
   | If you did not receive a copy of the Zend license and are unable to  |
   | obtain it through the world-wide-web, please send a note to          |
   | license@zend.com so we can mail you a copy immediately.              |
   +----------------------------------------------------------------------+
   | Authors: Andi Gutmans <andi@zend.com>                                |
   |          Zeev Suraski <zeev@zend.com>                                |
   +----------------------------------------------------------------------+
*/


#include <stdio.h>
#include <errno.h>
#include <stdlib.h>
#include <limits.h>
#include <ctype.h>

#include "zend.h"
#include "zend_operators.h"
#include "zend_variables.h"
#include "zend_globals.h"
#include "zend_list.h"
#include "zend_fast_cache.h"


#if WITH_BCMATH
#include "ext/bcmath/number.h"
#endif


ZEND_API void convert_scalar_to_number(zval *op)
{
	char *strval;

	if (op->type == IS_STRING) {
		strval = op->value.str.val;
		switch ((op->type=is_numeric_string(strval, op->value.str.len, &op->value.lval, &op->value.dval))) {
			case IS_DOUBLE:
			case IS_LONG:
				break;
#if WITH_BCMATH
			case FLAG_IS_BC:
				op->type = IS_DOUBLE; /* may have lost significant digits */
				break;
#endif
			default:
				op->value.lval = strtol(op->value.str.val, NULL, 10);
				op->type = IS_LONG;
				break;
		}
		STR_FREE(strval);
	} else if (op->type==IS_BOOL || op->type==IS_RESOURCE) {
		op->type = IS_LONG;
	} else if (op->type==IS_NULL) {
		op->type = IS_LONG;
		op->value.lval = 0;
	}
}

#define zendi_convert_scalar_to_number(op, holder, result)			\
	if (op==result) {												\
		convert_scalar_to_number(op);								\
	} else if ((op)->type == IS_STRING) {							\
		switch (((holder).type=is_numeric_string((op)->value.str.val, (op)->value.str.len, &(holder).value.lval, &(holder).value.dval))) {	\
			case IS_DOUBLE:											\
			case IS_LONG:											\
				break;												\
			case FLAG_IS_BC:												\
				(holder).type = IS_DOUBLE; /* may have lost significant digits */	\
				break;												\
			default:												\
				(holder).value.lval = strtol((op)->value.str.val, NULL, 10);		\
				(holder).type = IS_LONG;							\
				break;												\
		}															\
		(op) = &(holder);											\
	} else if ((op)->type==IS_BOOL || (op)->type==IS_RESOURCE) {	\
		(holder).value.lval = (op)->value.lval;						\
		(holder).type = IS_LONG;									\
		(op) = &(holder);											\
	} else if ((op)->type==IS_NULL) {								\
		(holder).value.lval = 0;									\
		(holder).type = IS_LONG;									\
		(op) = &(holder);											\
	}



#define zendi_convert_to_long(op, holder, result)					\
	if (op==result) {												\
		convert_to_long(op);										\
	} else if ((op)->type==IS_BOOL || (op)->type==IS_RESOURCE) {	\
		(holder).value.lval = (op)->value.lval;						\
		(holder).type = IS_LONG;									\
		(op) = &(holder);											\
	} else if ((op)->type != IS_LONG) {								\
		switch ((op)->type) {										\
			case IS_NULL:											\
				(holder).value.lval = 0;							\
				break;												\
			case IS_DOUBLE:											\
				(holder).value.lval = (long) (op)->value.dval;		\
				break;												\
			case IS_STRING:											\
				(holder).value.lval = strtol((op)->value.str.val, NULL, 10);		\
				break;												\
			case IS_ARRAY:											\
				(holder).value.lval = (zend_hash_num_elements((op)->value.ht)?1:0);	\
				break;												\
			case IS_OBJECT:											\
				(holder).value.lval = (zend_hash_num_elements((op)->value.obj.properties)?1:0);	\
				break;												\
			default:												\
				zend_error(E_WARNING, "Cannot convert to ordinal value");			\
				(holder).value.lval = 0;							\
				break;												\
		}															\
		(holder).type = IS_LONG;									\
		(op) = &(holder);											\
	}


#define zendi_convert_to_boolean(op, holder, result)				\
	if (op==result) {												\
		convert_to_boolean(op);										\
	} else if ((op)->type != IS_BOOL) {								\
		switch ((op)->type) {										\
			case IS_NULL:											\
				(holder).value.lval = 0;							\
				break;												\
			case IS_RESOURCE:										\
			case IS_LONG:											\
				(holder).value.lval = ((op)->value.lval ? 1 : 0);	\
				break;												\
			case IS_DOUBLE:											\
				(holder).value.lval = ((op)->value.dval ? 1 : 0);	\
				break;												\
			case IS_STRING:											\
				if ((op)->value.str.len == 0						\
					|| ((op)->value.str.len==1 && (op)->value.str.val[0]=='0')) {	\
					(holder).value.lval = 0;						\
				} else {											\
					(holder).value.lval = 1;						\
				}													\
				break;												\
			case IS_ARRAY:											\
				(holder).value.lval = (zend_hash_num_elements((op)->value.ht)?1:0);	\
				break;												\
			case IS_OBJECT:											\
				(holder).value.lval = (zend_hash_num_elements((op)->value.obj.properties)?1:0);	\
				break;												\
			default:												\
				(holder).value.lval = 0;							\
				break;												\
		}															\
		(holder).type = IS_BOOL;									\
		(op) = &(holder);											\
	}


ZEND_API void convert_to_long(zval *op)
{
	convert_to_long_base(op, 10);
}


ZEND_API void convert_to_long_base(zval *op, int base)
{
	char *strval;
	long tmp;

	switch (op->type) {
		case IS_NULL:
			op->value.lval = 0;
			break;
		case IS_RESOURCE:
		case IS_BOOL:
		case IS_LONG:
			break;
		case IS_DOUBLE:
			op->value.lval = (long) op->value.dval;
			break;
		case IS_STRING:
			strval = op->value.str.val;
			op->value.lval = strtol(strval, NULL, base);
			STR_FREE(strval);
			break;
		case IS_ARRAY:
			tmp = (zend_hash_num_elements(op->value.ht)?1:0);
			zval_dtor(op);
			op->value.lval = tmp;
			break;
		case IS_OBJECT:
			tmp = (zend_hash_num_elements(op->value.obj.properties)?1:0);
			zval_dtor(op);
			op->value.lval = tmp;
			break;
		default:
			zend_error(E_WARNING, "Cannot convert to ordinal value");
			zval_dtor(op);
			op->value.lval = 0;
			break;
	}

	op->type = IS_LONG;
}


ZEND_API void convert_to_double(zval *op)
{
	char *strval;
	double tmp;

	switch (op->type) {
		case IS_NULL:
			op->value.dval = 0.0;
			break;
		case IS_RESOURCE:
		case IS_BOOL:
		case IS_LONG:
			op->value.dval = (double) op->value.lval;
			break;
		case IS_DOUBLE:
			break;
		case IS_STRING:
			strval = op->value.str.val;

			op->value.dval = strtod(strval, NULL);
			STR_FREE(strval);
			break;
		case IS_ARRAY:
			tmp = (zend_hash_num_elements(op->value.ht)?1:0);
			zval_dtor(op);
			op->value.dval = tmp;
			break;
		case IS_OBJECT:
			tmp = (zend_hash_num_elements(op->value.obj.properties)?1:0);
			zval_dtor(op);
			op->value.dval = tmp;
			break;			
		default:
			zend_error(E_WARNING, "Cannot convert to real value (type=%d)", op->type);
			zval_dtor(op);
			op->value.dval = 0;
			break;
	}
	op->type = IS_DOUBLE;
}


ZEND_API void convert_to_unset(zval *op)
{
	zval_dtor(op);
	op->type = IS_NULL;
}


ZEND_API void convert_to_boolean(zval *op)
{
	char *strval;
	int tmp;

	switch (op->type) {
		case IS_BOOL:
			break;
		case IS_NULL:
			op->value.lval = 0;
			break;
		case IS_RESOURCE:
		case IS_LONG:
			op->value.lval = (op->value.lval ? 1 : 0);
			break;
		case IS_DOUBLE:
			op->value.lval = (op->value.dval ? 1 : 0);
			break;
		case IS_STRING:
			strval = op->value.str.val;

			if (op->value.str.len == 0
				|| (op->value.str.len==1 && op->value.str.val[0]=='0')) {
				op->value.lval = 0;
			} else {
				op->value.lval = 1;
			}
			STR_FREE(strval);
			break;
		case IS_ARRAY:
			tmp = (zend_hash_num_elements(op->value.ht)?1:0);
			zval_dtor(op);
			op->value.lval = tmp;
			break;
		case IS_OBJECT:
			tmp = (zend_hash_num_elements(op->value.obj.properties)?1:0);
			zval_dtor(op);
			op->value.lval = tmp;
			break;
		default:
			zval_dtor(op);
			op->value.lval = 0;
			break;
	}
	op->type = IS_BOOL;
}


ZEND_API void convert_to_string(zval *op)
{
	long lval;
	double dval;
	ELS_FETCH();

	switch (op->type) {
		case IS_NULL:
			op->value.str.val = empty_string;
			op->value.str.len = 0;
			break;
		case IS_STRING:
			break;
		case IS_BOOL:
			if (op->value.lval) {
				op->value.str.val = estrndup("1", 1);
				op->value.str.len = 1;
			} else {
				op->value.str.val = empty_string;
				op->value.str.len = 0;
			}
			break;
		case IS_LONG:
			lval = op->value.lval;

			op->value.str.val = (char *) emalloc(MAX_LENGTH_OF_LONG + 1);
			op->value.str.len = zend_sprintf(op->value.str.val, "%ld", lval);  /* SAFE */
			break;
		case IS_DOUBLE: {
			dval = op->value.dval;
			op->value.str.val = (char *) emalloc(MAX_LENGTH_OF_DOUBLE + EG(precision) + 1);
			op->value.str.len = zend_sprintf(op->value.str.val, "%.*G", (int) EG(precision), dval);  /* SAFE */
			/* %G already handles removing trailing zeros from the fractional part, yay */
			break;
		}
		case IS_ARRAY:
			zval_dtor(op);
			op->value.str.val = estrndup("Array",sizeof("Array")-1);
			op->value.str.len = sizeof("Array")-1;
			break;
		case IS_OBJECT:
			zval_dtor(op);
			op->value.str.val = estrndup("Object",sizeof("Object")-1);
			op->value.str.len = sizeof("Object")-1;
			break;
		default:
			zval_dtor(op);
			var_reset(op);
			break;
	}
	op->type = IS_STRING;
}


static void convert_scalar_to_array(zval *op, int type)
{
	zval *entry;
	
	ALLOC_ZVAL(entry);
	*entry = *op;
	INIT_PZVAL(entry);
	
	switch (type) {
		case IS_ARRAY:
			ALLOC_HASHTABLE(op->value.ht);
			zend_hash_init(op->value.ht, 0, NULL, ZVAL_PTR_DTOR, 0);
			zend_hash_index_update(op->value.ht, 0, (void *) &entry, sizeof(zval *), NULL);
			op->type = IS_ARRAY;
			break;
		case IS_OBJECT:
			ALLOC_HASHTABLE(op->value.obj.properties);
			zend_hash_init(op->value.obj.properties, 0, NULL, ZVAL_PTR_DTOR, 0);
			zend_hash_update(op->value.obj.properties, "scalar", sizeof("scalar"), (void *) &entry, sizeof(zval *), NULL);
			op->value.obj.ce = &zend_standard_class_def;
			op->type = IS_OBJECT;
			break;
	}
}


ZEND_API void convert_to_array(zval *op)
{
	switch(op->type) {
		case IS_ARRAY:
			return;
			break;
		case IS_OBJECT:
			op->type = IS_ARRAY;
			op->value.ht = op->value.obj.properties;
			return;
			break;
		default:
			convert_scalar_to_array(op, IS_ARRAY);
			break;
	}
}


ZEND_API void convert_to_object(zval *op)
{
	switch(op->type) {
		case IS_ARRAY:
			op->type = IS_OBJECT;
			op->value.obj.properties = op->value.ht;
			op->value.obj.ce = &zend_standard_class_def;
			return;
			break;
		case IS_OBJECT:
			return;
			break;
		default:
			convert_scalar_to_array(op, IS_OBJECT);
			break;
	}
}

		
ZEND_API int add_function(zval *result, zval *op1, zval *op2)
{
	zval op1_copy, op2_copy;

	if (op1->type == IS_ARRAY && op2->type == IS_ARRAY) {
		zval *tmp;

		if ((result == op1) && (result == op2)) {
			/* $a += $a */
			return SUCCESS;
		}
		if (result != op1) {
			/* $a += $b */
			*result = *op1;
			zval_copy_ctor(result);
		}
		zend_hash_merge(result->value.ht, op2->value.ht, (void (*)(void *pData)) zval_add_ref, (void *) &tmp, sizeof(zval *), 0);
		return SUCCESS;
	}
	zendi_convert_scalar_to_number(op1, op1_copy, result);
	zendi_convert_scalar_to_number(op2, op2_copy, result);


	if (op1->type == IS_LONG && op2->type == IS_LONG) {
		double dval = (double) op1->value.lval + (double) op2->value.lval;

		if (dval > (double) LONG_MAX) {
			result->value.dval = dval;
			result->type = IS_DOUBLE;
		} else {
			result->value.lval = op1->value.lval + op2->value.lval;
			result->type = IS_LONG;
		}
		return SUCCESS;
	}
	if ((op1->type == IS_DOUBLE && op2->type == IS_LONG)
		|| (op1->type == IS_LONG && op2->type == IS_DOUBLE)) {
		result->value.dval = (op1->type == IS_LONG ?
						 (((double) op1->value.lval) + op2->value.dval) :
						 (op1->value.dval + ((double) op2->value.lval)));
		result->type = IS_DOUBLE;
		return SUCCESS;
	}
	if (op1->type == IS_DOUBLE && op2->type == IS_DOUBLE) {
		result->type = IS_DOUBLE;
		result->value.dval = op1->value.dval + op2->value.dval;
		return SUCCESS;
	}
	zend_error(E_ERROR, "Unsupported operand types");
	return FAILURE;				/* unknown datatype */
}


ZEND_API int sub_function(zval *result, zval *op1, zval *op2)
{
	zval op1_copy, op2_copy;
	
	zendi_convert_scalar_to_number(op1, op1_copy, result);
	zendi_convert_scalar_to_number(op2, op2_copy, result);

	if (op1->type == IS_LONG && op2->type == IS_LONG) {
		double dval = (double) op1->value.lval - (double) op2->value.lval;

		if (dval < (double) LONG_MIN) {
			result->value.dval = dval;
			result->type = IS_DOUBLE;
		} else {
			result->value.lval = op1->value.lval - op2->value.lval;
			result->type = IS_LONG;
		}
		return SUCCESS;
	}
	if ((op1->type == IS_DOUBLE && op2->type == IS_LONG)
		|| (op1->type == IS_LONG && op2->type == IS_DOUBLE)) {
		result->value.dval = (op1->type == IS_LONG ?
						 (((double) op1->value.lval) - op2->value.dval) :
						 (op1->value.dval - ((double) op2->value.lval)));
		result->type = IS_DOUBLE;
		return SUCCESS;
	}
	if (op1->type == IS_DOUBLE && op2->type == IS_DOUBLE) {
		result->type = IS_DOUBLE;
		result->value.dval = op1->value.dval - op2->value.dval;
		return SUCCESS;
	}
	zend_error(E_ERROR, "Unsupported operand types");
	return FAILURE;				/* unknown datatype */
}


ZEND_API int mul_function(zval *result, zval *op1, zval *op2)
{
	zval op1_copy, op2_copy;
	
	zendi_convert_scalar_to_number(op1, op1_copy, result);
	zendi_convert_scalar_to_number(op2, op2_copy, result);

	if (op1->type == IS_LONG && op2->type == IS_LONG) {
		double dval = (double) op1->value.lval * (double) op2->value.lval;

		if (dval > (double) LONG_MAX) {
			result->value.dval = dval;
			result->type = IS_DOUBLE;
		} else {
			result->value.lval = op1->value.lval * op2->value.lval;
			result->type = IS_LONG;
		}
		return SUCCESS;
	}
	if ((op1->type == IS_DOUBLE && op2->type == IS_LONG)
		|| (op1->type == IS_LONG && op2->type == IS_DOUBLE)) {
		result->value.dval = (op1->type == IS_LONG ?
						 (((double) op1->value.lval) * op2->value.dval) :
						 (op1->value.dval * ((double) op2->value.lval)));
		result->type = IS_DOUBLE;
		return SUCCESS;
	}
	if (op1->type == IS_DOUBLE && op2->type == IS_DOUBLE) {
		result->type = IS_DOUBLE;
		result->value.dval = op1->value.dval * op2->value.dval;
		return SUCCESS;
	}
	zend_error(E_ERROR, "Unsupported operand types");
	return FAILURE;				/* unknown datatype */
}

ZEND_API int div_function(zval *result, zval *op1, zval *op2)
{
	zval op1_copy, op2_copy;
	
	zendi_convert_scalar_to_number(op1, op1_copy, result);
	zendi_convert_scalar_to_number(op2, op2_copy, result);

	if ((op2->type == IS_LONG && op2->value.lval == 0) || (op2->type == IS_DOUBLE && op2->value.dval == 0.0)) {
		zend_error(E_WARNING, "Division by zero");
		var_reset(result);
		return FAILURE;			/* division by zero */
	}
	if (op1->type == IS_LONG && op2->type == IS_LONG) {
		if (op1->value.lval % op2->value.lval == 0) { /* integer */
			result->type = IS_LONG;
			result->value.lval = op1->value.lval / op2->value.lval;
		} else {
			result->type = IS_DOUBLE;
			result->value.dval = ((double) op1->value.lval) / op2->value.lval;
		}
		return SUCCESS;
	}
	if ((op1->type == IS_DOUBLE && op2->type == IS_LONG)
		|| (op1->type == IS_LONG && op2->type == IS_DOUBLE)) {
		result->value.dval = (op1->type == IS_LONG ?
						 (((double) op1->value.lval) / op2->value.dval) :
						 (op1->value.dval / ((double) op2->value.lval)));
		result->type = IS_DOUBLE;
		return SUCCESS;
	}
	if (op1->type == IS_DOUBLE && op2->type == IS_DOUBLE) {
		result->type = IS_DOUBLE;
		result->value.dval = op1->value.dval / op2->value.dval;
		return SUCCESS;
	}
	zend_error(E_ERROR, "Unsupported operand types");
	return FAILURE;				/* unknown datatype */
}


ZEND_API int mod_function(zval *result, zval *op1, zval *op2)
{
	zval op1_copy, op2_copy;
	
	zendi_convert_to_long(op1, op1_copy, result);
	zendi_convert_to_long(op2, op2_copy, result);

	if (op2->value.lval == 0) {
		var_reset(result);
		return FAILURE;			/* modulus by zero */
	}

	result->type = IS_LONG;
	result->value.lval = op1->value.lval % op2->value.lval;
	return SUCCESS;
}


ZEND_API int boolean_or_function(zval *result, zval *op1, zval *op2)
{
	zval op1_copy, op2_copy;
	
	result->type = IS_BOOL;

	zendi_convert_to_boolean(op1, op1_copy, result);
	if (op1->value.lval) {
		result->value.lval = 1;
		return SUCCESS;
	}
	zendi_convert_to_boolean(op2, op2_copy, result);
	if (op2->value.lval) {
		result->value.lval = 1;
		return SUCCESS;
	}
	result->value.lval = 0;
	return SUCCESS;
}


ZEND_API int boolean_and_function(zval *result, zval *op1, zval *op2)
{
	zval op1_copy, op2_copy;
	
	result->type = IS_BOOL;

	zendi_convert_to_boolean(op1, op1_copy, result);
	if (!op1->value.lval) {
		result->value.lval = 0;
		return SUCCESS;
	}
	zendi_convert_to_boolean(op2, op2_copy, result);
	if (!op2->value.lval) {
		result->value.lval = 0;
		return SUCCESS;
	}
	result->value.lval = 1;
	return SUCCESS;
}


ZEND_API int boolean_xor_function(zval *result, zval *op1, zval *op2)
{
	zval op1_copy, op2_copy;
	
	result->type = IS_BOOL;

	zendi_convert_to_boolean(op1, op1_copy, result);
	zendi_convert_to_boolean(op2, op2_copy, result);
	result->value.lval = op1->value.lval ^ op2->value.lval;
	return SUCCESS;
}


ZEND_API int boolean_not_function(zval *result, zval *op1)
{
	zval op1_copy;
	
	zendi_convert_to_boolean(op1, op1_copy, result);

	result->type = IS_BOOL;
	result->value.lval = !op1->value.lval;
	return SUCCESS;
}


ZEND_API int bitwise_not_function(zval *result, zval *op1)
{
	zval op1_copy = *op1;
	
	op1 = &op1_copy;
	
	if (op1->type == IS_DOUBLE) {
		op1->value.lval = (long) op1->value.dval;
		op1->type = IS_LONG;
	}
	if (op1->type == IS_LONG) {
		result->value.lval = ~op1->value.lval;
		result->type = IS_LONG;
		return SUCCESS;
	}
	if (op1->type == IS_STRING) {
		int i;

		result->type = IS_STRING;
		result->value.str.val = estrndup(op1->value.str.val, op1->value.str.len);
		result->value.str.len = op1->value.str.len;
		for (i = 0; i < op1->value.str.len; i++) {
			result->value.str.val[i] = ~op1->value.str.val[i];
		}
		return SUCCESS;
	}
	zend_error(E_ERROR, "Unsupported operand types");
	return FAILURE;				/* unknown datatype */
}


ZEND_API int bitwise_or_function(zval *result, zval *op1, zval *op2)
{
	zval op1_copy, op2_copy;
	
	if (op1->type == IS_STRING && op2->type == IS_STRING) {
		zval *longer, *shorter;
		int i;

		if (op1->value.str.len >= op2->value.str.len) {
			longer = op1;
			shorter = op2;
		} else {
			longer = op2;
			shorter = op1;
		}

		result->value.str.len = longer->value.str.len;
		result->value.str.val = estrndup(longer->value.str.val, longer->value.str.len);
		for (i = 0; i < shorter->value.str.len; i++) {
			result->value.str.val[i] |= shorter->value.str.val[i];
		}
		return SUCCESS;
	}
	zendi_convert_to_long(op1, op1_copy, result);
	zendi_convert_to_long(op2, op2_copy, result);

	result->type = IS_LONG;
	result->value.lval = op1->value.lval | op2->value.lval;
	return SUCCESS;
}


ZEND_API int bitwise_and_function(zval *result, zval *op1, zval *op2)
{
	zval op1_copy, op2_copy;
	
	if (op1->type == IS_STRING && op2->type == IS_STRING) {
		zval *longer, *shorter;
		int i;

		if (op1->value.str.len >= op2->value.str.len) {
			longer = op1;
			shorter = op2;
		} else {
			longer = op2;
			shorter = op1;
		}

		result->value.str.len = shorter->value.str.len;
		result->value.str.val = estrndup(shorter->value.str.val, shorter->value.str.len);
		for (i = 0; i < shorter->value.str.len; i++) {
			result->value.str.val[i] &= longer->value.str.val[i];
		}
		return SUCCESS;
	}
	

	zendi_convert_to_long(op1, op1_copy, result);
	zendi_convert_to_long(op2, op2_copy, result);

	result->type = IS_LONG;
	result->value.lval = op1->value.lval & op2->value.lval;
	return SUCCESS;
}


ZEND_API int bitwise_xor_function(zval *result, zval *op1, zval *op2)
{
	zval op1_copy, op2_copy;
	
	if (op1->type == IS_STRING && op2->type == IS_STRING) {
		zval *longer, *shorter;
		int i;

		if (op1->value.str.len >= op2->value.str.len) {
			longer = op1;
			shorter = op2;
		} else {
			longer = op2;
			shorter = op1;
		}

		result->value.str.len = shorter->value.str.len;
		result->value.str.val = estrndup(shorter->value.str.val, shorter->value.str.len);
		for (i = 0; i < shorter->value.str.len; i++) {
			result->value.str.val[i] ^= longer->value.str.val[i];
		}
		return SUCCESS;
	}

	zendi_convert_to_long(op1, op1_copy, result);
	zendi_convert_to_long(op2, op2_copy, result);	

	result->type = IS_LONG;
	result->value.lval = op1->value.lval ^ op2->value.lval;
	return SUCCESS;
}


ZEND_API int shift_left_function(zval *result, zval *op1, zval *op2)
{
	zval op1_copy, op2_copy;
	
	zendi_convert_to_long(op1, op1_copy, result);
	zendi_convert_to_long(op2, op2_copy, result);
	result->value.lval = op1->value.lval << op2->value.lval;
	result->type = IS_LONG;
	return SUCCESS;
}


ZEND_API int shift_right_function(zval *result, zval *op1, zval *op2)
{
	zval op1_copy, op2_copy;
	
	zendi_convert_to_long(op1, op1_copy, result);
	zendi_convert_to_long(op2, op2_copy, result);
	result->value.lval = op1->value.lval >> op2->value.lval;
	result->type = IS_LONG;
	return SUCCESS;
}



/* must support result==op1 */
ZEND_API int add_char_to_string(zval *result, zval *op1, zval *op2)
{
	result->value.str.len = op1->value.str.len + 1;
	result->value.str.val = (char *) erealloc(op1->value.str.val, result->value.str.len+1);
    result->value.str.val[result->value.str.len - 1] = op2->value.chval;
	result->value.str.val[result->value.str.len] = 0;
	result->type = IS_STRING;
	return SUCCESS;
}


/* must support result==op1 */
ZEND_API int add_string_to_string(zval *result, zval *op1, zval *op2)
{
	int length = op1->value.str.len + op2->value.str.len;
	result->value.str.val = (char *) erealloc(op1->value.str.val, length+1);
    memcpy(result->value.str.val+op1->value.str.len, op2->value.str.val, op2->value.str.len);
    result->value.str.val[length] = 0;
	result->value.str.len = length;
	result->type = IS_STRING;
	return SUCCESS;
}


ZEND_API int concat_function(zval *result, zval *op1, zval *op2)
{
	zval op1_copy, op2_copy;
	int use_copy1, use_copy2;


	zend_make_printable_zval(op1, &op1_copy, &use_copy1);
	zend_make_printable_zval(op2, &op2_copy, &use_copy2);

	if (use_copy1) {
		op1 = &op1_copy;
	}
	if (use_copy2) {
		op2 = &op2_copy;
	}
	if (result==op1) {	/* special case, perform operations on result */
		uint res_len = op1->value.str.len + op2->value.str.len;
		
		if (result->value.str.len == 0) { /* handle empty_string */
			STR_FREE(result->value.str.val);
			result->value.str.val = emalloc(res_len+1);
		} else {
			result->value.str.val = erealloc(result->value.str.val, res_len+1);
		}
		memcpy(result->value.str.val+result->value.str.len, op2->value.str.val, op2->value.str.len);
		result->value.str.val[res_len]=0;
		result->value.str.len = res_len;
	} else {
		result->value.str.len = op1->value.str.len + op2->value.str.len;
		result->value.str.val = (char *) emalloc(result->value.str.len + 1);
		memcpy(result->value.str.val, op1->value.str.val, op1->value.str.len);
		memcpy(result->value.str.val+op1->value.str.len, op2->value.str.val,op2->value.str.len);
		result->value.str.val[result->value.str.len] = 0;
		result->type = IS_STRING;
	}
	if (use_copy1) {
		zval_dtor(op1);
	}
	if (use_copy2) {
		zval_dtor(op2);
	}
	return SUCCESS;
}


ZEND_API int compare_function(zval *result, zval *op1, zval *op2)
{
	zval op1_copy, op2_copy;

	if (op1->type == IS_STRING && op2->type == IS_STRING) {
		zendi_smart_strcmp(result, op1, op2);
		return SUCCESS;
	}
	
	if (op1->type == IS_BOOL || op2->type == IS_BOOL
		|| op1->type == IS_NULL || op2->type == IS_NULL) {
		zendi_convert_to_boolean(op1, op1_copy, result);
		zendi_convert_to_boolean(op2, op2_copy, result);
		result->type = IS_LONG;
		result->value.lval = op1->value.lval - op2->value.lval;
		return SUCCESS;
	}

	zendi_convert_scalar_to_number(op1, op1_copy, result);
	zendi_convert_scalar_to_number(op2, op2_copy, result);

	if (op1->type == IS_LONG && op2->type == IS_LONG) {
		result->type = IS_LONG;
		result->value.lval = op1->value.lval - op2->value.lval;
		return SUCCESS;
	}
	if ((op1->type == IS_DOUBLE || op1->type == IS_LONG)
		&& (op2->type == IS_DOUBLE || op2->type == IS_LONG)) {
		result->value.dval = (op1->type == IS_LONG ? (double) op1->value.lval : op1->value.dval) - (op2->type == IS_LONG ? (double) op2->value.lval : op2->value.dval);
		result->type = IS_DOUBLE;
		return SUCCESS;
	}
	if ((op1->type==IS_ARRAY || op1->type==IS_OBJECT)
		&& (op2->type==IS_ARRAY || op2->type==IS_OBJECT)) {
		zend_error(E_WARNING,"Cannot compare arrays or objects");
	}
	var_reset(result);
	return FAILURE;
}


ZEND_API int is_identical_function(zval *result, zval *op1, zval *op2)
{
	result->type = IS_BOOL;
	if (op1->type != op2->type) {
		result->value.lval = 0;
		return SUCCESS;
	}
	switch (op1->type) {
		case IS_NULL:
			result->value.lval = (op2->type==IS_NULL);
			return SUCCESS;
			break;
		case IS_BOOL:
		case IS_LONG:
		case IS_RESOURCE:
			result->value.lval = (op1->value.lval == op2->value.lval);
			return SUCCESS;
			break;
		case IS_DOUBLE:
			result->value.lval = (op1->value.dval == op2->value.dval);
			return SUCCESS;
			break;
		case IS_STRING:
			if ((op1->value.str.len == op2->value.str.len)
				&& (!memcmp(op1->value.str.val, op2->value.str.val, op1->value.str.len))) {
				result->value.lval = 1;
			} else {
				result->value.lval = 0;
			}
			return SUCCESS;
			break;
		case IS_ARRAY:
		case IS_OBJECT:
			zend_error(E_WARNING,"Cannot compare arrays or objects");
			break;
	}
	var_reset(result);
	return FAILURE;
}

ZEND_API int is_equal_function(zval *result, zval *op1, zval *op2)
{
	if (compare_function(result, op1, op2) == FAILURE) {
		return FAILURE;
	}
	convert_to_boolean(result);
	if (result->value.lval == 0) {
		result->value.lval = 1;
	} else {
		result->value.lval = 0;
	}
	return SUCCESS;
}


ZEND_API int is_not_equal_function(zval *result, zval *op1, zval *op2)
{
	if (compare_function(result, op1, op2) == FAILURE) {
		return FAILURE;
	}
	convert_to_boolean(result);
	if (result->value.lval) {
		result->value.lval = 1;
	} else {
		result->value.lval = 0;
	}
	return SUCCESS;
}


ZEND_API int is_smaller_function(zval *result, zval *op1, zval *op2)
{
	if (compare_function(result, op1, op2) == FAILURE) {
		return FAILURE;
	}
	if (result->type == IS_LONG) {
		if (result->value.lval < 0) {
			result->value.lval = 1;
		} else {
			result->value.lval = 0;
		}
		return SUCCESS;
	}
	if (result->type == IS_DOUBLE) {
		result->type = IS_LONG;
		if (result->value.dval < 0) {
			result->value.lval = 1;
		} else {
			result->value.lval = 0;
		}
		return SUCCESS;
	}
	zend_error(E_ERROR, "Unsupported operand types");
	return FAILURE;
}


ZEND_API int is_smaller_or_equal_function(zval *result, zval *op1, zval *op2)
{
	if (compare_function(result, op1, op2) == FAILURE) {
		return FAILURE;
	}
	if (result->type == IS_LONG) {
		if (result->value.lval <= 0) {
			result->value.lval = 1;
		} else {
			result->value.lval = 0;
		}
		return SUCCESS;
	}
	if (result->type == IS_DOUBLE) {
		result->type = IS_LONG;
		if (result->value.dval <= 0) {
			result->value.lval = 1;
		} else {
			result->value.lval = 0;
		}
		return SUCCESS;
	}
	zend_error(E_ERROR, "Unsupported operand types");
	return FAILURE;
}


#define LOWER_CASE 1
#define UPPER_CASE 2
#define NUMERIC 3


static void increment_string(zval *str)
{
    int carry=0;
    int pos=str->value.str.len-1;
    char *s=str->value.str.val;
    char *t;
    int last=0; /* Shut up the compiler warning */
    int ch;
    
	while(pos >= 0) {
        ch = s[pos];
        if (ch >= 'a' && ch <= 'z') {
            if (ch == 'z') {
                s[pos] = 'a';
                carry=1;
            } else {
                s[pos]++;
                carry=0;
            }
            last=LOWER_CASE;
        } else if (ch >= 'A' && ch <= 'Z') {
            if (ch == 'Z') {
                s[pos] = 'A';
                carry=1;
            } else {
                s[pos]++;
                carry=0;
            }
            last=UPPER_CASE;
        } else if (ch >= '0' && ch <= '9') {
            if (ch == '9') {
                s[pos] = '0';
                carry=1;
            } else {
                s[pos]++;
                carry=0;
            }
            last = NUMERIC;
        } else {
            carry=0;
            break;
        }
        if (carry == 0) {
            break;
        }
        pos--;
    }

    if (carry) {
        t = (char *) emalloc(str->value.str.len+1+1);
        memcpy(t+1,str->value.str.val, str->value.str.len);
        str->value.str.len++;
        t[str->value.str.len] = '\0';
        switch (last) {
            case NUMERIC:
            	t[0] = '1';
            	break;
            case UPPER_CASE:
            	t[0] = 'A';
            	break;
            case LOWER_CASE:
            	t[0] = 'a';
            	break;
        }
        STR_FREE(str->value.str.val);
        str->value.str.val = t;
    }
}


ZEND_API int increment_function(zval *op1)
{
	switch (op1->type) {
		case IS_LONG:
			op1->value.lval++;
			break;
		case IS_DOUBLE:
			op1->value.dval = op1->value.dval + 1;
			break;
		case IS_NULL:
			op1->value.lval = 1;
			op1->type = IS_LONG;
			break;
		case IS_STRING: /* Perl style string increment */
			increment_string(op1);
			break;
		default:
			return FAILURE;
	}
	return SUCCESS;
}


ZEND_API int decrement_function(zval *op1)
{
	long lval;
	
	switch (op1->type) {
		case IS_LONG:
			op1->value.lval--;
			break;
		case IS_DOUBLE:
			op1->value.dval = op1->value.dval - 1;
			break;
		case IS_STRING:		/* Like perl we only support string increment */
			if (op1->value.str.len==0) { /* consider as 0 */
				STR_FREE(op1->value.str.val);
				op1->value.lval = -1;
				op1->type = IS_LONG;
				break;
			} else if (is_numeric_string(op1->value.str.val, op1->value.str.len, &lval, NULL)==IS_LONG) { /* long */
				STR_FREE(op1->value.str.val);
				op1->value.lval = lval-1;
				op1->type = IS_LONG;
				break;
			}
			break;
		default:
			return FAILURE;
	}

	return SUCCESS;
}


ZEND_API int zval_is_true(zval *op)
{
	convert_to_boolean(op);
	return (op->value.lval ? 1 : 0);
}


ZEND_API void zend_str_tolower(char *str, unsigned int length)
{
	register char *p=str, *end=p+length;
	
	while (p<end) {
		*p = tolower(*p);
		p++;
	}
}


ZEND_API int zend_binary_strcmp(zval *s1, zval *s2)
{
	int retval;
	
	retval = memcmp(s1->value.str.val, s2->value.str.val, MIN(s1->value.str.len,s2->value.str.len));
	if (!retval) {
		return (s1->value.str.len - s2->value.str.len);
	} else {
		return retval;
	}
}


ZEND_API int zend_binary_strcasecmp(zval *s1, zval *s2)
{
	const unsigned char *p1 = (const unsigned char *)s1->value.str.val;
	const unsigned char *p2 = (const unsigned char *)s2->value.str.val;
	unsigned char c1 = 0, c2 = 0;
	int len1, len2;

	len1 = s1->value.str.len;
	len2 = s2->value.str.len;
	if (len1 != len2 || !len1) {
		return len1 - len2;
	}

	while (len1--) {
		c1 = tolower(*p1++);
		c2 = tolower(*p2++);
		if (c1 != c2) {
			break;
		}
	}

	return c1 - c2;
}

ZEND_API void zendi_smart_strcmp(zval *result, zval *s1, zval *s2)
{
	int ret1,ret2;
	long lval1, lval2;
	double dval1, dval2;
	
	if ((ret1=is_numeric_string(s1->value.str.val, s1->value.str.len, &lval1, &dval1)) &&
		(ret2=is_numeric_string(s2->value.str.val, s2->value.str.len, &lval2, &dval2))) {
#if WITH_BCMATH
		if ((ret1==FLAG_IS_BC) || (ret2==FLAG_IS_BC)) {
			bc_num first, second;
			
			/* use the BC math library to compare the numbers */
			init_num(&first);
			init_num(&second);
			str2num(&first,s1->value.str.val,100); /* this scale should do */
			str2num(&second,s2->value.str.val,100); /* ditto */
			result->value.lval = bc_compare(first,second);
			result->type = IS_LONG;
			free_num(&first);
			free_num(&second);
		} else
#endif
		if ((ret1==IS_DOUBLE) || (ret2==IS_DOUBLE)) {
			if (ret1!=IS_DOUBLE) {
				dval1 = strtod(s1->value.str.val, NULL);
			} else if (ret2!=IS_DOUBLE) {
				dval2 = strtod(s2->value.str.val, NULL);
			}
			result->value.dval = dval1 - dval2;
			result->type = IS_DOUBLE;
		} else { /* they both have to be long's */
			result->value.lval = lval1 - lval2;
			result->type = IS_LONG;
		}
	} else {
		result->value.lval = zend_binary_strcmp(s1,s2);
		result->type = IS_LONG;
	}
	return;	
}


/* returns 0 for non-numeric string
 * returns IS_DOUBLE for floating point string, and assigns the value to *dval (if it's not NULL)
 * returns IS_LONG for integer strings, and assigns the value to *lval (if it's not NULL)
 * returns FLAG_IS_BC if the number might lose accuracy when converted to a double
 */
 
#if 1
ZEND_API inline int is_numeric_string(char *str, int length, long *lval, double *dval)
{
	long local_lval;
	double local_dval;
	char *end_ptr;

	if (!length) {
		return 0;
	}
	
	errno=0;
	local_lval = strtol(str, &end_ptr, 10);
	if (errno!=ERANGE && end_ptr == str+length) { /* integer string */
		if (lval) {
			*lval = local_lval;
		}
		return IS_LONG;
	}

	errno=0;
	local_dval = strtod(str, &end_ptr);
	if (errno!=ERANGE && end_ptr == str+length) { /* floating point string */
		if (dval) {
			*dval = local_dval;
		}
#if WITH_BCMATH
		if (length>16) {
			register char *ptr=str, *end=str+length;
			
			while(ptr<end) {
				switch(*ptr++) {
					case 'e':
					case 'E':
						/* scientific notation, not handled by the BC library */
						return IS_DOUBLE;
						break;
					default:
						break;
				}
			}
			return FLAG_IS_BC;
		} else {
			return IS_DOUBLE;
		}
#else
		return IS_DOUBLE;
#endif
	}
	
	return 0;
}

#else

static inline int is_numeric_string(char *str, int length, long *lval, double *dval)
{
	register char *p=str, *end=str+length;
	unsigned char had_period=0,had_exponent=0;
	char *end_ptr;
	
	if (!length) {
		return 0;
	}
	switch (*p) {
		case '-':
		case '+':
			while (*++p==' ');  /* ignore spaces after the sign */
			break;
		default:
			break;
	}
	while (p<end) {
		if (isdigit((int)(unsigned char)*p)) {
			p++;
		} else if (*p=='.') {
			if (had_period) {
				return 0;
			} else {
				had_period=1;
				p++;
			}
		} else if (*p=='e' || *p=='E') {
			p++;
			if (is_numeric_string(p, length - (int) (p-str), NULL, NULL)==IS_LONG) { /* valid exponent */
				had_exponent=1;
				break;
			} else {
				return 0;
			}
		} else {
			return 0;
		}
	}
	errno=0;
	if (had_period || had_exponent) { /* floating point number */
		double local_dval;
		
		local_dval = strtod(str, &end_ptr);
		if (errno==ERANGE || end_ptr != str+length) { /* overflow or bad string */
			return 0;
		} else {
			if (dval) {
				*dval = local_dval;
			}
			return IS_DOUBLE;
		}
	} else {
		long local_lval;
		
		local_lval = strtol(str, &end_ptr, 10);
		if (errno==ERANGE || end_ptr != str+length) { /* overflow or bad string */
			return 0;
		} else {
			if (lval) {
				*lval = local_lval;
			}
			return IS_LONG;
		}
	}
}

#endif