atexit.c revision 23662
11573Srgrimes/*- 21573Srgrimes * Copyright (c) 1990, 1993 31573Srgrimes * The Regents of the University of California. All rights reserved. 41573Srgrimes * 51573Srgrimes * This code is derived from software contributed to Berkeley by 61573Srgrimes * Chris Torek. 71573Srgrimes * 81573Srgrimes * Redistribution and use in source and binary forms, with or without 91573Srgrimes * modification, are permitted provided that the following conditions 101573Srgrimes * are met: 111573Srgrimes * 1. Redistributions of source code must retain the above copyright 121573Srgrimes * notice, this list of conditions and the following disclaimer. 131573Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 141573Srgrimes * notice, this list of conditions and the following disclaimer in the 151573Srgrimes * documentation and/or other materials provided with the distribution. 161573Srgrimes * 3. All advertising materials mentioning features or use of this software 171573Srgrimes * must display the following acknowledgement: 181573Srgrimes * This product includes software developed by the University of 191573Srgrimes * California, Berkeley and its contributors. 201573Srgrimes * 4. Neither the name of the University nor the names of its contributors 211573Srgrimes * may be used to endorse or promote products derived from this software 221573Srgrimes * without specific prior written permission. 231573Srgrimes * 241573Srgrimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 251573Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 261573Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 271573Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 281573Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 291573Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 301573Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 311573Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 321573Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 331573Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 341573Srgrimes * SUCH DAMAGE. 351573Srgrimes */ 361573Srgrimes 371573Srgrimes#if defined(LIBC_SCCS) && !defined(lint) 3823662Speterstatic char sccsid[] = "@(#)atexit.c 8.2 (Berkeley) 7/3/94"; 391573Srgrimes#endif /* LIBC_SCCS and not lint */ 401573Srgrimes 411573Srgrimes#include <stddef.h> 421573Srgrimes#include <stdlib.h> 4318516Sphk#include <unistd.h> 441573Srgrimes#include "atexit.h" 451573Srgrimes 4623662Speterstruct atexit *__atexit; /* points to head of LIFO stack */ 4723662Speter 481573Srgrimes/* 491573Srgrimes * Register a function to be performed at exit. 501573Srgrimes */ 511573Srgrimesint 521573Srgrimesatexit(fn) 531573Srgrimes void (*fn)(); 541573Srgrimes{ 551573Srgrimes static struct atexit __atexit0; /* one guaranteed table */ 561573Srgrimes register struct atexit *p; 571573Srgrimes 581573Srgrimes if ((p = __atexit) == NULL) 591573Srgrimes __atexit = p = &__atexit0; 601573Srgrimes else if (p->ind >= ATEXIT_SIZE) { 6118516Sphk if ((p = (struct atexit *)sbrk(sizeof(*p))) == (struct atexit *)-1) 621573Srgrimes return (-1); 631573Srgrimes p->ind = 0; 641573Srgrimes p->next = __atexit; 651573Srgrimes __atexit = p; 661573Srgrimes } 671573Srgrimes p->fns[p->ind++] = fn; 681573Srgrimes return (0); 691573Srgrimes} 70