1/* Copyright (C) 2002-2018 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <http://www.gnu.org/licenses/>. */
18
19#include <lowlevellock.h>
20
21/* The fork generation counter, defined in libpthread. */
22extern unsigned long int __fork_generation attribute_hidden;
23
24/* Pointer to the fork generation counter in the thread library. */
25extern unsigned long int *__fork_generation_pointer attribute_hidden;
26
27/* Lock to protect allocation and deallocation of fork handlers. */
28extern int __fork_lock attribute_hidden;
29
30/* Elements of the fork handler lists. */
31struct fork_handler
32{
33 struct fork_handler *next;
34 void (*prepare_handler) (void);
35 void (*parent_handler) (void);
36 void (*child_handler) (void);
37 void *dso_handle;
38 unsigned int refcntr;
39 int need_signal;
40};
41
42/* The single linked list of all currently registered for handlers. */
43extern struct fork_handler *__fork_handlers attribute_hidden;
44
45
46/* Function to call to unregister fork handlers. */
47extern void __unregister_atfork (void *dso_handle) attribute_hidden;
48#define UNREGISTER_ATFORK(dso_handle) __unregister_atfork (dso_handle)
49
50
51/* C library side function to register new fork handlers. */
52extern int __register_atfork (void (*__prepare) (void),
53 void (*__parent) (void),
54 void (*__child) (void),
55 void *dso_handle);
56libc_hidden_proto (__register_atfork)
57
58/* Add a new element to the fork list. */
59extern void __linkin_atfork (struct fork_handler *newp) attribute_hidden;
60