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Commit	Line	Data
	1	/*
	2	* Copyright (c) 1990 Regents of the University of California.
	3	* All rights reserved.
	4	*
	5	* %sccs.include.redist.c%
	6	*/
	7
	8
	9	/*
	10
	11	@deftypefun int xatexit (void (*@var{fn}) (void))
	12
	13	Behaves as the standard @code{atexit} function, but with no limit on
	14	the number of registered functions. Returns 0 on success, or @minus{}1 on
	15	failure. If you use @code{xatexit} to register functions, you must use
	16	@code{xexit} to terminate your program.
	17
	18	@end deftypefun
	19
	20	*/
	21
	22	/* Adapted from newlib/libc/stdlib/{,at}exit.[ch].
	23	If you use xatexit, you must call xexit instead of exit. */
	24
	25	#include "ansidecl.h"
	26	#include "libiberty.h"
	27
	28	#include <stdio.h>
	29
	30	#ifdef ANSI_PROTOTYPES
	31	#include <stddef.h>
	32	#else
	33	#define size_t unsigned long
	34	#endif
	35
	36	#if VMS
	37	#include <stdlib.h>
	38	#include <unixlib.h>
	39	#else
	40	/* For systems with larger pointers than ints, this must be declared. */
	41	PTR malloc PARAMS ((size_t));
	42	#endif
	43
	44	static void xatexit_cleanup PARAMS ((void));
	45
	46	/* Pointer to function run by xexit. */
	47	extern void (*_xexit_cleanup) PARAMS ((void));
	48
	49	#define XATEXIT_SIZE 32
	50
	51	struct xatexit {
	52	struct xatexit next; / next in list */
	53	int ind; /* next index in this table */
	54	void (fns[XATEXIT_SIZE]) PARAMS ((void)); / the table itself */
	55	};
	56
	57	/* Allocate one struct statically to guarantee that we can register
	58	at least a few handlers. */
	59	static struct xatexit xatexit_first;
	60
	61	/* Points to head of LIFO stack. */
	62	static struct xatexit *xatexit_head = &xatexit_first;
	63
	64	/* Register function FN to be run by xexit.
	65	Return 0 if successful, -1 if not. */
	66
	67	int
	68	xatexit (fn)
	69	void (*fn) PARAMS ((void));
	70	{
	71	register struct xatexit *p;
	72
	73	/* Tell xexit to call xatexit_cleanup. */
	74	if (!_xexit_cleanup)
	75	_xexit_cleanup = xatexit_cleanup;
	76
	77	p = xatexit_head;
	78	if (p->ind >= XATEXIT_SIZE)
	79	{
	80	if ((p = (struct xatexit ) malloc (sizeof p)) == NULL)
	81	return -1;
	82	p->ind = 0;
	83	p->next = xatexit_head;
	84	xatexit_head = p;
	85	}
	86	p->fns[p->ind++] = fn;
	87	return 0;
	88	}
	89
	90	/* Call any cleanup functions. */
	91
	92	static void
	93	xatexit_cleanup ()
	94	{
	95	register struct xatexit *p;
	96	register int n;
	97
	98	for (p = xatexit_head; p; p = p->next)
	99	for (n = p->ind; --n >= 0;)
	100	(*p->fns[n]) ();
	101	}