1/* syssignal.h - System-dependent definitions for signals.
2   Copyright (C) 1993, 1999, 2001, 2002, 2003, 2004,
3                 2005, 2006, 2007  Free Software Foundation, Inc.
4
5This file is part of GNU Emacs.
6
7GNU Emacs is free software; you can redistribute it and/or modify
8it under the terms of the GNU General Public License as published by
9the Free Software Foundation; either version 2, or (at your option)
10any later version.
11
12GNU Emacs is distributed in the hope that it will be useful,
13but WITHOUT ANY WARRANTY; without even the implied warranty of
14MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15GNU General Public License for more details.
16
17You should have received a copy of the GNU General Public License
18along with GNU Emacs; see the file COPYING.  If not, write to
19the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
20Boston, MA 02110-1301, USA.  */
21
22extern void init_signals P_ ((void));
23
24#ifdef HAVE_GTK_AND_PTHREAD
25#include <pthread.h>
26extern pthread_t main_thread;
27#endif
28
29#ifdef POSIX_SIGNALS
30
31/* Don't #include <signal.h>.  That header should always be #included
32   before "config.h", because some configuration files (like s/hpux.h)
33   indicate that SIGIO doesn't work by #undef-ing SIGIO.  If this file
34   #includes <signal.h>, then that will re-#define SIGIO and confuse
35   things.  */
36
37#define SIGMASKTYPE sigset_t
38
39#define SIGEMPTYMASK (empty_mask)
40#define SIGFULLMASK (full_mask)
41extern sigset_t empty_mask, full_mask;
42
43/* POSIX pretty much destroys any possibility of writing sigmask as a
44   macro in standard C.  We always define our own version because the
45   predefined macro in Glibc 2.1 is only provided for compatility for old
46   programs that use int as signal mask type.  */
47#undef sigmask
48#ifdef __GNUC__
49#define sigmask(SIG) 				\
50  ({						\
51    sigset_t _mask;				\
52    sigemptyset (&_mask);			\
53    sigaddset (&_mask, SIG);			\
54    _mask;					\
55  })
56#else /* ! defined (__GNUC__) */
57extern sigset_t sys_sigmask ();
58#define sigmask(SIG) (sys_sigmask (SIG))
59#endif /* ! defined (__GNUC__) */
60
61#undef sigpause
62#define sigpause(MASK)    sigsuspend (&(MASK))
63
64#define sigblock(SIG)    sys_sigblock (SIG)
65#define sigunblock(SIG)  sys_sigunblock (SIG)
66#ifndef sigsetmask
67#define sigsetmask(SIG)  sys_sigsetmask (SIG)
68#endif
69#define sighold(SIG)     ONLY_USED_IN_BSD_4_1
70#define sigrelse(SIG)    ONLY_USED_IN_BSD_4_1
71#undef signal
72#define signal(SIG,ACT)      sys_signal(SIG,ACT)
73
74/* Whether this is what all systems want or not, this is what
75   appears to be assumed in the source, for example data.c:arith_error.  */
76typedef RETSIGTYPE (*signal_handler_t) (/*int*/);
77
78signal_handler_t sys_signal P_ ((int signal_number, signal_handler_t action));
79sigset_t sys_sigblock   P_ ((sigset_t new_mask));
80sigset_t sys_sigunblock P_ ((sigset_t new_mask));
81sigset_t sys_sigsetmask P_ ((sigset_t new_mask));
82
83#define sys_sigdel(MASK,SIG) sigdelset (&MASK,SIG)
84
85#else /* ! defined (POSIX_SIGNALS) */
86#ifdef USG5_4
87
88extern SIGMASKTYPE sigprocmask_set;
89
90#ifndef sigblock
91#define sigblock(sig)					\
92     (sigprocmask_set = SIGEMPTYMASK | (sig),		\
93      sigprocmask (SIG_BLOCK, &sigprocmask_set, NULL))
94#endif
95
96#ifndef sigunblock
97#define sigunblock(sig)						\
98     (sigprocmask_set = SIGFULLMASK & ~(sig),			\
99      sigprocmask (SIG_SETMASK, &sigprocmask_set, NULL))
100#endif
101
102#else
103#ifdef USG
104
105#ifndef sigunblock
106#define sigunblock(sig)
107#endif
108
109#else
110
111#ifndef sigunblock
112#define sigunblock(SIG) \
113{ SIGMASKTYPE omask = sigblock (SIGEMPTYMASK); sigsetmask (omask & ~SIG); }
114#endif
115
116#endif /* ! defined (USG) */
117#endif /* ! defined (USG5_4) */
118#endif /* ! defined (POSIX_SIGNALS) */
119
120#ifndef SIGMASKTYPE
121#define SIGMASKTYPE int
122#endif
123
124#ifndef SIGEMPTYMASK
125#define SIGEMPTYMASK (0)
126#endif
127
128#ifndef SIGFULLMASK
129#define SIGFULLMASK (0xffffffff)
130#endif
131
132#ifndef sigmask
133#define sigmask(no) (1L << ((no) - 1))
134#endif
135
136#ifndef sigunblock
137#define sigunblock(SIG) \
138{ SIGMASKTYPE omask = sigblock (SIGFULLMASK); sigsetmask (omask & ~SIG); }
139#endif
140
141#ifndef BSD4_1
142#define sigfree() sigsetmask (SIGEMPTYMASK)
143#endif /* not BSD4_1 */
144
145#if defined (SIGINFO) && defined (BROKEN_SIGINFO)
146#undef SIGINFO
147#endif
148#if defined (SIGIO) && defined (BROKEN_SIGIO)
149# undef SIGIO
150# if defined (__Lynx__)
151# undef SIGPOLL /* Defined as SIGIO on LynxOS */
152# endif
153#endif
154#if defined (SIGPOLL) && defined (BROKEN_SIGPOLL)
155#undef SIGPOLL
156#endif
157#if defined (SIGTSTP) && defined (BROKEN_SIGTSTP)
158#undef SIGTSTP
159#endif
160#if defined (SIGURG) && defined (BROKEN_SIGURG)
161#undef SIGURG
162#endif
163#if defined (SIGAIO) && defined (BROKEN_SIGAIO)
164#undef SIGAIO
165#endif
166#if defined (SIGPTY) && defined (BROKEN_SIGPTY)
167#undef SIGPTY
168#endif
169
170
171#if NSIG < NSIG_MINIMUM
172# ifdef NSIG
173#  undef NSIG
174# endif
175# define NSIG NSIG_MINIMUM
176#endif
177
178#ifdef BSD4_1
179#define SIGIO SIGTINT
180/* sigfree is in sysdep.c */
181#endif /* BSD4_1 */
182
183/* On bsd, [man says] kill does not accept a negative number to kill a pgrp.
184   Must do that using the killpg call.  */
185#ifdef BSD_SYSTEM
186#define EMACS_KILLPG(gid, signo) (killpg ( (gid), (signo)))
187#else
188#ifdef WINDOWSNT
189#define EMACS_KILLPG(gid, signo) (kill (gid, signo))
190#else
191#define EMACS_KILLPG(gid, signo) (kill   (-(gid), (signo)))
192#endif
193#endif
194
195/* Define SIGCHLD as an alias for SIGCLD.  There are many conditionals
196   testing SIGCHLD.  */
197#ifndef VMS
198#ifdef SIGCLD
199#ifndef SIGCHLD
200#define SIGCHLD SIGCLD
201#endif /* SIGCHLD */
202#endif /* ! defined (SIGCLD) */
203#endif /* VMS */
204
205#ifndef HAVE_STRSIGNAL
206/* strsignal is in sysdep.c */
207char *strsignal ();
208#endif
209
210#ifdef HAVE_GTK_AND_PTHREAD
211#define SIGNAL_THREAD_CHECK(signo)                                      \
212  do {                                                                  \
213    if (!pthread_equal (pthread_self (), main_thread))			\
214      {                                                                 \
215        /* POSIX says any thread can receive the signal.  On GNU/Linux  \
216           that is not true, but for other systems (FreeBSD at least)   \
217           it is.  So direct the signal to the correct thread and block \
218           it from this thread.  */                                     \
219        sigset_t new_mask;                                              \
220                                                                        \
221        sigemptyset (&new_mask);                                        \
222        sigaddset (&new_mask, signo);                                   \
223        pthread_sigmask (SIG_BLOCK, &new_mask, 0);                      \
224        pthread_kill (main_thread, signo);                              \
225        return;                                                         \
226      }                                                                 \
227   } while (0)
228
229#else /* not HAVE_GTK_AND_PTHREAD */
230#define SIGNAL_THREAD_CHECK(signo)
231#endif /* not HAVE_GTK_AND_PTHREAD */
232/* arch-tag: 4580e86a-340d-4574-9e11-a742b6e1a152
233   (do not change this comment) */
234