1 /* Copyright (C) 2002, 2003, 2006, 2007 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. */ 22 extern unsigned long int __fork_generation attribute_hidden; 23 24 /* Pointer to the fork generation counter in the thread library. */ 25 extern unsigned long int *__fork_generation_pointer attribute_hidden; 26 27 /* Lock to protect allocation and deallocation of fork handlers. */ 28 extern int __fork_lock attribute_hidden; 29 30 /* Elements of the fork handler lists. */ 31 struct 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. */ 43 extern struct fork_handler *__fork_handlers attribute_hidden; 44 45 46 /* Function to call to unregister fork handlers. */ 47 extern 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. */ 52 extern int __register_atfork (void (*__prepare) (void), 53 void (*__parent) (void), 54 void (*__child) (void), 55 void *dso_handle); 56 libc_hidden_proto (__register_atfork) 57 58 /* Add a new element to the fork list. */ 59 extern void __linkin_atfork (struct fork_handler *newp) attribute_hidden; 60