util.c

/*
 * vtsh - A mashup of virtual terminal and shell
 * Copyright (c) 2021, Tommi Leino <namhas@gmail.com>
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include "util.h"
#include "config.h"

#include <stdlib.h>
#include <string.h>
#include <assert.h>

/*
 * Returns -1 if error.
 */
int
grow_array(void **arr, size_t sz, size_t *max_elem)
{
	size_t target;
	void *tmp;

	assert(arr != NULL);
	assert(sz > 0);

	target = (*max_elem) * 2;
	if (target == 0)
		target = ALLOC_CHUNK;

	if ((tmp = realloc(*arr, target * sz)) == NULL)
		return -1;

	*arr = tmp;
	*max_elem = target;
	return 0;
}