/*
 * Copyright (c) 2015, Vicent Marti
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#include "stack.h"
#include <string.h>

int
redcarpet_stack_grow(struct stack *st, size_t new_size)
{
	void **new_st;

	if (st->asize >= new_size)
		return 0;

	new_st = realloc(st->item, new_size * sizeof(void *));
	if (new_st == NULL)
		return -1;

	memset(new_st + st->asize, 0x0,
		(new_size - st->asize) * sizeof(void *));

	st->item = new_st;
	st->asize = new_size;

	if (st->size > new_size)
		st->size = new_size;

	return 0;
}

void
redcarpet_stack_free(struct stack *st)
{
	if (!st)
		return;

	free(st->item);

	st->item = NULL;
	st->size = 0;
	st->asize = 0;
}

int
redcarpet_stack_init(struct stack *st, size_t initial_size)
{
	st->item = NULL;
	st->size = 0;
	st->asize = 0;

	if (!initial_size)
		initial_size = 8;

	return redcarpet_stack_grow(st, initial_size);
}

int
redcarpet_stack_push(struct stack *st, void *item)
{
	if (redcarpet_stack_grow(st, st->size * 2) < 0)
		return -1;

	st->item[st->size++] = item;
	return 0;
}