/* $OpenBSD: doalloc.c,v 1.8 2023/10/17 09:52:09 nicm Exp $ */

/****************************************************************************
 * Copyright 2020,2021 Thomas E. Dickey                                     *
 * Copyright 1998-2002,2012 Free Software Foundation, Inc.                  *
 *                                                                          *
 * 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, distribute with modifications, 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 ABOVE 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.                               *
 *                                                                          *
 * Except as contained in this notice, the name(s) of the above copyright   *
 * holders shall not be used in advertising or otherwise to promote the     *
 * sale, use or other dealings in this Software without prior written       *
 * authorization.                                                           *
 ****************************************************************************/

/****************************************************************************
 *  Author: Thomas E. Dickey <dickey@clark.net> 1998                        *
 ****************************************************************************/

/*
 * Wrapper for malloc/realloc.  Standard implementations allow realloc with
 * a null pointer, but older libraries may not (e.g., SunOS).
 *
 * Also if realloc fails, we discard the old memory to avoid leaks.
 */

#include <curses.priv.h>

MODULE_ID("$Id: doalloc.c,v 1.8 2023/10/17 09:52:09 nicm Exp $")

void *
_nc_doalloc(void *oldp, size_t amount)
{
    void *newp;

    if (oldp != NULL) {
	if (amount == 0) {
	    free(oldp);
	    newp = NULL;
	} else if ((newp = realloc(oldp, amount)) == 0) {
	    free(oldp);
	    errno = ENOMEM;	/* just in case 'free' reset */
	}
    } else {
	newp = malloc(amount);
    }
    return newp;
}