1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253
|
/*
* Copyright (C) 1996-2000 Michael R. Elkins <me@mutt.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#if HAVE_CONFIG_H
# include "config.h"
#endif
#include "mutt.h"
#include "mutt_curses.h"
#include <signal.h>
#include <string.h>
#include <sys/wait.h>
#include <errno.h>
static sigset_t Sigset;
static sigset_t SigsetSys;
static struct sigaction SysOldInt;
static struct sigaction SysOldQuit;
static int IsEndwin = 0;
/* Attempt to catch "ordinary" signals and shut down gracefully. */
RETSIGTYPE exit_handler (int sig)
{
curs_set (1);
endwin (); /* just to be safe */
#if SYS_SIGLIST_DECLARED
printf(_("%s... Exiting.\n"), sys_siglist[sig]);
#else
#if (__sun__ && __svr4__)
printf(_("Caught %s... Exiting.\n"), _sys_siglist[sig]);
#else
#if (__alpha && __osf__)
printf(_("Caught %s... Exiting.\n"), __sys_siglist[sig]);
#else
printf(_("Caught signal %d... Exiting.\n"), sig);
#endif
#endif
#endif
exit (0);
}
RETSIGTYPE chld_handler (int sig)
{
/* empty */
}
RETSIGTYPE sighandler (int sig)
{
int save_errno = errno;
switch (sig)
{
case SIGTSTP: /* user requested a suspend */
if (!option (OPTSUSPEND))
break;
IsEndwin = isendwin ();
curs_set (1);
if (!IsEndwin)
endwin ();
kill (0, SIGSTOP);
case SIGCONT:
if (!IsEndwin)
refresh ();
mutt_curs_set (-1);
#if defined (USE_SLANG_CURSES) || defined (HAVE_RESIZETERM)
/* We don't receive SIGWINCH when suspended; however, no harm is done by
* just assuming we received one, and triggering the 'resize' anyway. */
SigWinch = 1;
#endif
break;
#if defined (USE_SLANG_CURSES) || defined (HAVE_RESIZETERM)
case SIGWINCH:
SigWinch = 1;
break;
#endif
case SIGINT:
SigInt = 1;
break;
}
errno = save_errno;
}
#ifdef USE_SLANG_CURSES
int mutt_intr_hook (void)
{
return (-1);
}
#endif /* USE_SLANG_CURSES */
void mutt_signal_init (void)
{
struct sigaction act;
sigemptyset (&act.sa_mask);
act.sa_flags = 0;
act.sa_handler = SIG_IGN;
sigaction (SIGPIPE, &act, NULL);
act.sa_handler = exit_handler;
sigaction (SIGTERM, &act, NULL);
sigaction (SIGHUP, &act, NULL);
sigaction (SIGQUIT, &act, NULL);
/* we want to avoid race conditions */
sigaddset (&act.sa_mask, SIGTSTP);
act.sa_handler = sighandler;
/* we want SIGALRM to abort the current syscall, so we do this before
* setting the SA_RESTART flag below. currently this is only used to
* timeout on a connect() call in a reasonable amout of time.
*/
sigaction (SIGALRM, &act, NULL);
/* we also don't want to mess with interrupted system calls */
#ifdef SA_RESTART
act.sa_flags = SA_RESTART;
#endif
sigaction (SIGCONT, &act, NULL);
sigaction (SIGTSTP, &act, NULL);
sigaction (SIGINT, &act, NULL);
#if defined (USE_SLANG_CURSES) || defined (HAVE_RESIZETERM)
sigaction (SIGWINCH, &act, NULL);
#endif
/* POSIX doesn't allow us to ignore SIGCHLD,
* so we just install a dummy handler for it
*/
act.sa_handler = chld_handler;
/* don't need to block any other signals here */
sigemptyset (&act.sa_mask);
/* we don't want to mess with stopped children */
act.sa_flags |= SA_NOCLDSTOP;
sigaction (SIGCHLD, &act, NULL);
#ifdef USE_SLANG_CURSES
/* This bit of code is required because of the implementation of
* SLcurses_wgetch(). If a signal is received (like SIGWINCH) when we
* are in blocking mode, SLsys_getkey() will not return an error unless
* a handler function is defined and it returns -1. This is needed so
* that if the user resizes the screen while at a prompt, it will just
* abort and go back to the main-menu.
*/
SLang_getkey_intr_hook = mutt_intr_hook;
#endif
}
/* signals which are important to block while doing critical ops */
void mutt_block_signals (void)
{
if (!option (OPTSIGNALSBLOCKED))
{
sigemptyset (&Sigset);
sigaddset (&Sigset, SIGTERM);
sigaddset (&Sigset, SIGHUP);
sigaddset (&Sigset, SIGTSTP);
sigaddset (&Sigset, SIGINT);
#if defined (USE_SLANG_CURSES) || defined (HAVE_RESIZETERM)
sigaddset (&Sigset, SIGWINCH);
#endif
sigprocmask (SIG_BLOCK, &Sigset, 0);
set_option (OPTSIGNALSBLOCKED);
}
}
/* restore the previous signal mask */
void mutt_unblock_signals (void)
{
if (option (OPTSIGNALSBLOCKED))
{
sigprocmask (SIG_UNBLOCK, &Sigset, 0);
unset_option (OPTSIGNALSBLOCKED);
}
}
void mutt_block_signals_system (void)
{
struct sigaction sa;
if (! option (OPTSYSSIGNALSBLOCKED))
{
/* POSIX: ignore SIGINT and SIGQUIT & block SIGCHLD before exec */
sa.sa_handler = SIG_IGN;
sa.sa_flags = 0;
sigemptyset (&sa.sa_mask);
sigaction (SIGINT, &sa, &SysOldInt);
sigaction (SIGQUIT, &sa, &SysOldQuit);
sigemptyset (&SigsetSys);
sigaddset (&SigsetSys, SIGCHLD);
sigprocmask (SIG_BLOCK, &SigsetSys, 0);
set_option (OPTSYSSIGNALSBLOCKED);
}
}
void mutt_unblock_signals_system (int catch)
{
if (option (OPTSYSSIGNALSBLOCKED))
{
sigprocmask (SIG_UNBLOCK, &SigsetSys, NULL);
if (catch)
{
sigaction (SIGQUIT, &SysOldQuit, NULL);
sigaction (SIGINT, &SysOldInt, NULL);
}
else
{
struct sigaction sa;
sa.sa_handler = SIG_DFL;
sigemptyset (&sa.sa_mask);
sa.sa_flags = 0;
sigaction (SIGQUIT, &sa, NULL);
sigaction (SIGINT, &sa, NULL);
}
unset_option (OPTSYSSIGNALSBLOCKED);
}
}
void mutt_allow_interrupt (int disposition)
{
struct sigaction sa;
memset (&sa, 0, sizeof sa);
sa.sa_handler = sighandler;
#ifdef SA_RESTART
if (disposition == 0)
sa.sa_flags |= SA_RESTART;
#endif
sigaction (SIGINT, &sa, NULL);
}
|