From b3925d944ed94cc76bbcbb14a799ec9beeb8d1bf Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 10 Apr 2024 22:25:44 +0200 Subject: Adding upstream version 1.21.4. Signed-off-by: Daniel Baumann --- lib/fatal-signal.h | 101 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 101 insertions(+) create mode 100644 lib/fatal-signal.h (limited to 'lib/fatal-signal.h') diff --git a/lib/fatal-signal.h b/lib/fatal-signal.h new file mode 100644 index 0000000..fed4f4b --- /dev/null +++ b/lib/fatal-signal.h @@ -0,0 +1,101 @@ +/* Emergency actions in case of a fatal signal. + Copyright (C) 2003-2004, 2009-2023 Free Software Foundation, Inc. + Written by Bruno Haible , 2003. + + This file is free software: you can redistribute it and/or modify + it under the terms of the GNU Lesser General Public License as + published by the Free Software Foundation; either version 2.1 of the + License, or (at your option) any later version. + + This file is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with this program. If not, see . */ + + +#ifndef _FATAL_SIGNAL_H +#define _FATAL_SIGNAL_H + +/* This file uses _GL_ASYNC_SAFE. */ +#if !_GL_CONFIG_H_INCLUDED + #error "Please include config.h first." +#endif + +#include + +#ifdef __cplusplus +extern "C" { +#endif + + +/* It is often useful to do some cleanup action when a usually fatal signal + terminates the process, like removing a temporary file or killing a + subprocess that may be stuck waiting for a device, pipe or network input. + Such signals are SIGHUP, SIGINT, SIGPIPE, SIGTERM, and possibly others. + The limitation of this facility is that it cannot work for SIGKILL. + + Signals with a SIG_IGN handler are considered to be non-fatal. The + functions in this file assume that when a SIG_IGN handler is installed + for a signal, it was installed before any functions in this file were + called and it stays so for the whole lifetime of the process. */ + +/* Register a cleanup function to be executed when a catchable fatal signal + occurs. + + Restrictions for the cleanup function: + - The cleanup function can do all kinds of system calls. It may also + modify (clobber) errno. + - It can also access application dependent memory locations and data + structures provided they are in a consistent state. One way to ensure + this is through block_fatal_signals()/unblock_fatal_signals(), see + below. Another - more tricky - way to ensure this is the careful use + of 'volatile'. + However, + - malloc() and similarly complex facilities are not safe to be called + because they are not guaranteed to be in a consistent state. + - Also, the cleanup function must not block the catchable fatal signals + and leave them blocked upon return. + + The cleanup function is executed asynchronously. It is unspecified + whether during its execution the catchable fatal signals are blocked + or not. + + Return 0 upon success, or -1 if there was a memory allocation problem. */ +extern int at_fatal_signal (_GL_ASYNC_SAFE void (*function) (int sig)); + + +/* Sometimes it is necessary to block the usually fatal signals while the + data structures being accessed by the cleanup action are being built or + reorganized. This is the case, for example, when a temporary file or + directory is created through mkstemp() or mkdtemp(), because these + functions create the temporary file or directory _before_ returning its + name to the application. */ + +/* Temporarily delay the catchable fatal signals. + The signals will be blocked (= delayed) until the next call to + unblock_fatal_signals(). If the signals are already blocked, a further + call to block_fatal_signals() has no effect. */ +extern void block_fatal_signals (void); + +/* Stop delaying the catchable fatal signals. */ +extern void unblock_fatal_signals (void); + + +/* Return the list of signals that block_fatal_signals/unblock_fatal_signals + would block or unblock. + Fills signals[0..count-1] and returns count. */ +extern unsigned int get_fatal_signals (int signals[64]); + +/* Return the list of signals that block_fatal_signals/unblock_fatal_signals + would block or unblock. */ +extern const sigset_t * get_fatal_signal_set (void); + + +#ifdef __cplusplus +} +#endif + +#endif /* _FATAL_SIGNAL_H */ -- cgit v1.2.3