ncurses/tinfo/doalloc.c

/****************************************************************************
 * Copyright 2020,2021 Thomas E. Dickey                                     *
 * Copyright 1998-2002,2012 Free Software Foundation, Inc.                  *
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/****************************************************************************
 *  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 1.14 2021/04/24 23:43:39 tom 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;
}