/*
   +----------------------------------------------------------------------+
   | Zend Engine                                                          |
   +----------------------------------------------------------------------+
   | Copyright (c) 1998-2002 Zend Technologies Ltd. (http://www.zend.com) |
   +----------------------------------------------------------------------+
   | This source file is subject to version 2.00 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/2_00.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>                                |
   +----------------------------------------------------------------------+
*/


#ifndef ZEND_PTR_STACK_H
#define ZEND_PTR_STACK_H

typedef struct _zend_ptr_stack {
	int top, max;
	void **elements;
	void **top_element;
} zend_ptr_stack;


#define PTR_STACK_BLOCK_SIZE 64

ZEND_API void zend_ptr_stack_init(zend_ptr_stack *stack);
ZEND_API void zend_ptr_stack_n_push(zend_ptr_stack *stack, int count, ...);
ZEND_API void zend_ptr_stack_n_pop(zend_ptr_stack *stack, int count, ...);
ZEND_API void zend_ptr_stack_destroy(zend_ptr_stack *stack);
ZEND_API void zend_ptr_stack_apply(zend_ptr_stack *stack, void (*func)(void *));
ZEND_API void zend_ptr_stack_clean(zend_ptr_stack *stack, void (*func)(void *), zend_bool free_elements);
ZEND_API int zend_ptr_stack_num_elements(zend_ptr_stack *stack);

static inline void zend_ptr_stack_push(zend_ptr_stack *stack, void *ptr)
{
	if (stack->top >= stack->max) {		/* we need to allocate more memory */
		stack->elements = (void **) erealloc(stack->elements, (sizeof(void *) * (stack->max *= 2 )));
		stack->top_element = stack->elements+stack->top;
	}
	stack->top++;
	*(stack->top_element++) = ptr;
}

static inline void *zend_ptr_stack_pop(zend_ptr_stack *stack)
{
	stack->top--;
	return *(--stack->top_element);
}


#endif /* ZEND_PTR_STACK_H */
