Merge branch 'master' of ssh://crater.dragonflybsd.org/repository/git/dragonfly
[dragonfly.git] / contrib / gcc-3.4 / libiberty / xatexit.c
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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
13Behaves as the standard @code{atexit} function, but with no limit on
14the number of registered functions. Returns 0 on success, or @minus{}1 on
15failure. 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. */
41PTR malloc PARAMS ((size_t));
42#endif
43
44static void xatexit_cleanup PARAMS ((void));
45
46/* Pointer to function run by xexit. */
47extern void (*_xexit_cleanup) PARAMS ((void));
48
49#define XATEXIT_SIZE 32
50
51struct 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. */
59static struct xatexit xatexit_first;
60
61/* Points to head of LIFO stack. */
62static 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
67int
68xatexit (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
92static void
93xatexit_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}