src/syssignal.h

   1 /* syssignal.h - System-dependent definitions for signals.
   2    Copyright (C) 1993, 1999, 2001, 2002, 2003, 2004,
   3                  2005, 2006, 2007, 2008  Free Software Foundation, Inc.
   4
   5 This file is part of GNU Emacs.
   6
   7 GNU Emacs is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 3, or (at your option)
  10 any later version.
  11
  12 GNU Emacs is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GNU Emacs; see the file COPYING.  If not, write to
  19 the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  20 Boston, MA 02110-1301, USA.  */
  21
  22 extern void init_signals P_ ((void));
  23
  24 #ifdef HAVE_GTK_AND_PTHREAD
  25 #include <pthread.h>
  26 extern 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 /* XXX This is not correct anymore, there is a BROKEN_SIGIO macro. */
  37
  38 #define SIGMASKTYPE sigset_t
  39
  40 #define SIGEMPTYMASK (empty_mask)
  41 #define SIGFULLMASK (full_mask)
  42 extern sigset_t empty_mask, full_mask;
  43
  44 /* POSIX pretty much destroys any possibility of writing sigmask as a
  45    macro in standard C.  We always define our own version because the
  46    predefined macro in Glibc 2.1 is only provided for compatility for old
  47    programs that use int as signal mask type.  */
  48 #undef sigmask
  49 #ifdef __GNUC__
  50 #define sigmask(SIG)                            \
  51   ({                                            \
  52     sigset_t _mask;                             \
  53     sigemptyset (&_mask);                       \
  54     sigaddset (&_mask, SIG);                    \
  55     _mask;                                      \
  56   })
  57 #else /* ! defined (__GNUC__) */
  58 extern sigset_t sys_sigmask ();
  59 #define sigmask(SIG) (sys_sigmask (SIG))
  60 #endif /* ! defined (__GNUC__) */
  61
  62 #undef sigpause
  63 #define sigpause(MASK)    sigsuspend (&(MASK))
  64
  65 #define sigblock(SIG)    sys_sigblock (SIG)
  66 #define sigunblock(SIG)  sys_sigunblock (SIG)
  67 #ifndef sigsetmask
  68 #define sigsetmask(SIG)  sys_sigsetmask (SIG)
  69 #endif
  70 #define sighold(SIG)     ONLY_USED_IN_BSD_4_1
  71 #define sigrelse(SIG)    ONLY_USED_IN_BSD_4_1
  72 #undef signal
  73 #define signal(SIG,ACT)      sys_signal(SIG,ACT)
  74
  75 /* Whether this is what all systems want or not, this is what
  76    appears to be assumed in the source, for example data.c:arith_error.  */
  77 typedef RETSIGTYPE (*signal_handler_t) (/*int*/);
  78
  79 signal_handler_t sys_signal P_ ((int signal_number, signal_handler_t action));
  80 sigset_t sys_sigblock   P_ ((sigset_t new_mask));
  81 sigset_t sys_sigunblock P_ ((sigset_t new_mask));
  82 sigset_t sys_sigsetmask P_ ((sigset_t new_mask));
  83
  84 #define sys_sigdel(MASK,SIG) sigdelset (&MASK,SIG)
  85
  86 #else /* ! defined (POSIX_SIGNALS) */
  87 #ifdef USG5_4
  88
  89 extern SIGMASKTYPE sigprocmask_set;
  90
  91 #ifndef sigblock
  92 #define sigblock(sig)                                   \
  93      (sigprocmask_set = SIGEMPTYMASK | (sig),           \
  94       sigprocmask (SIG_BLOCK, &sigprocmask_set, NULL))
  95 #endif
  96
  97 #ifndef sigunblock
  98 #define sigunblock(sig)                                         \
  99      (sigprocmask_set = SIGFULLMASK & ~(sig),                   \
 100       sigprocmask (SIG_SETMASK, &sigprocmask_set, NULL))
 101 #endif
 102
 103 #else
 104 #ifdef USG
 105
 106 #ifndef sigunblock
 107 #define sigunblock(sig)
 108 #endif
 109
 110 #else
 111
 112 #ifndef sigunblock
 113 #define sigunblock(SIG) \
 114 { SIGMASKTYPE omask = sigblock (SIGEMPTYMASK); sigsetmask (omask & ~SIG); }
 115 #endif
 116
 117 #endif /* ! defined (USG) */
 118 #endif /* ! defined (USG5_4) */
 119 #endif /* ! defined (POSIX_SIGNALS) */
 120
 121 #ifndef SIGMASKTYPE
 122 #define SIGMASKTYPE int
 123 #endif
 124
 125 #ifndef SIGEMPTYMASK
 126 #define SIGEMPTYMASK (0)
 127 #endif
 128
 129 #ifndef SIGFULLMASK
 130 #define SIGFULLMASK (0xffffffff)
 131 #endif
 132
 133 #ifndef sigmask
 134 #define sigmask(no) (1L << ((no) - 1))
 135 #endif
 136
 137 #ifndef sigunblock
 138 #define sigunblock(SIG) \
 139 { SIGMASKTYPE omask = sigblock (SIGFULLMASK); sigsetmask (omask & ~SIG); }
 140 #endif
 141
 142 #ifndef BSD4_1
 143 #define sigfree() sigsetmask (SIGEMPTYMASK)
 144 #endif /* not BSD4_1 */
 145
 146 #if defined (SIGINFO) && defined (BROKEN_SIGINFO)
 147 #undef SIGINFO
 148 #endif
 149 #if defined (SIGIO) && defined (BROKEN_SIGIO)
 150 # undef SIGIO
 151 # if defined (__Lynx__)
 152 # undef SIGPOLL /* Defined as SIGIO on LynxOS */
 153 # endif
 154 #endif
 155 #if defined (SIGPOLL) && defined (BROKEN_SIGPOLL)
 156 #undef SIGPOLL
 157 #endif
 158 #if defined (SIGTSTP) && defined (BROKEN_SIGTSTP)
 159 #undef SIGTSTP
 160 #endif
 161 #if defined (SIGURG) && defined (BROKEN_SIGURG)
 162 #undef SIGURG
 163 #endif
 164 #if defined (SIGAIO) && defined (BROKEN_SIGAIO)
 165 #undef SIGAIO
 166 #endif
 167 #if defined (SIGPTY) && defined (BROKEN_SIGPTY)
 168 #undef SIGPTY
 169 #endif
 170
 171
 172 #if NSIG < NSIG_MINIMUM
 173 # ifdef NSIG
 174 #  undef NSIG
 175 # endif
 176 # define NSIG NSIG_MINIMUM
 177 #endif
 178
 179 #ifdef BSD4_1
 180 #define SIGIO SIGTINT
 181 /* sigfree is in sysdep.c */
 182 #endif /* BSD4_1 */
 183
 184 /* On bsd, [man says] kill does not accept a negative number to kill a pgrp.
 185    Must do that using the killpg call.  */
 186 #ifdef BSD_SYSTEM
 187 #define EMACS_KILLPG(gid, signo) (killpg ( (gid), (signo)))
 188 #else
 189 #ifdef WINDOWSNT
 190 #define EMACS_KILLPG(gid, signo) (kill (gid, signo))
 191 #else
 192 #define EMACS_KILLPG(gid, signo) (kill   (-(gid), (signo)))
 193 #endif
 194 #endif
 195
 196 /* Define SIGCHLD as an alias for SIGCLD.  There are many conditionals
 197    testing SIGCHLD.  */
 198 #ifndef VMS
 199 #ifdef SIGCLD
 200 #ifndef SIGCHLD
 201 #define SIGCHLD SIGCLD
 202 #endif /* SIGCHLD */
 203 #endif /* ! defined (SIGCLD) */
 204 #endif /* VMS */
 205
 206 #ifndef HAVE_STRSIGNAL
 207 /* strsignal is in sysdep.c */
 208 char *strsignal ();
 209 #endif
 210
 211 #ifdef HAVE_GTK_AND_PTHREAD
 212 #define SIGNAL_THREAD_CHECK(signo)                                      \
 213   do {                                                                  \
 214     if (!pthread_equal (pthread_self (), main_thread))                  \
 215       {                                                                 \
 216         /* POSIX says any thread can receive the signal.  On GNU/Linux  \
 217            that is not true, but for other systems (FreeBSD at least)   \
 218            it is.  So direct the signal to the correct thread and block \
 219            it from this thread.  */                                     \
 220         sigset_t new_mask;                                              \
 221                                                                         \
 222         sigemptyset (&new_mask);                                        \
 223         sigaddset (&new_mask, signo);                                   \
 224         pthread_sigmask (SIG_BLOCK, &new_mask, 0);                      \
 225         pthread_kill (main_thread, signo);                              \
 226         return;                                                         \
 227       }                                                                 \
 228    } while (0)
 229
 230 #else /* not HAVE_GTK_AND_PTHREAD */
 231 #define SIGNAL_THREAD_CHECK(signo)
 232 #endif /* not HAVE_GTK_AND_PTHREAD */
 233 /* arch-tag: 4580e86a-340d-4574-9e11-a742b6e1a152
 234    (do not change this comment) */