\f
-/* Set nonzero to make following function work under dbx
- (at least for bsd). */
-int wait_debugging EXTERNALLY_VISIBLE;
-
#ifndef MSDOS
static void
{
while (1)
{
-#if (defined (BSD_SYSTEM) || defined (HPUX)) && !defined (__GNU__)
- /* Note that kill returns -1 even if the process is just a zombie now.
- But inevitably a SIGCHLD interrupt should be generated
- and child_sig will do waitpid and make the process go away. */
- /* There is some indication that there is a bug involved with
- termination of subprocesses, perhaps involving a kernel bug too,
- but no idea what it is. Just as a hunch we signal SIGCHLD to see
- if that causes the problem to go away or get worse. */
- sigset_t sigchild_mask;
- sigemptyset (&sigchild_mask);
- sigaddset (&sigchild_mask, SIGCHLD);
- pthread_sigmask (SIG_SETMASK, &sigchild_mask, 0);
-
- if (0 > kill (pid, 0))
- {
- pthread_sigmask (SIG_SETMASK, &empty_mask, 0);
- kill (getpid (), SIGCHLD);
- break;
- }
- if (wait_debugging)
- sleep (1);
- else
- sigsuspend (&empty_mask);
-#else /* not BSD_SYSTEM, and not HPUX version >= 6 */
#ifdef WINDOWSNT
wait (0);
break;
#else /* not WINDOWSNT */
- sigset_t blocked;
- sigemptyset (&blocked);
- sigaddset (&blocked, SIGCHLD);
- pthread_sigmask (SIG_BLOCK, &blocked, 0);
- errno = 0;
- if (kill (pid, 0) == -1 && errno == ESRCH)
+ int status;
+ int wait_result = waitpid (pid, &status, 0);
+ if (wait_result < 0)
{
- pthread_sigmask (SIG_UNBLOCK, &blocked, 0);
+ if (errno != EINTR)
+ break;
+ }
+ else
+ {
+ record_child_status_change (wait_result, status);
break;
}
- sigsuspend (&empty_mask);
#endif /* not WINDOWSNT */
-#endif /* not BSD_SYSTEM, and not HPUX version >= 6 */
if (interruptible)
QUIT;
}
\f
sigset_t empty_mask;
-/* Store into *ACTION a signal action suitable for Emacs, with handler
- HANDLER. */
-void
-emacs_sigaction_init (struct sigaction *action, signal_handler_t handler)
+static struct sigaction process_fatal_action;
+
+static int
+emacs_sigaction_flags (void)
{
- sigemptyset (&action->sa_mask);
- action->sa_handler = handler;
- action->sa_flags = 0;
-#if defined (SA_RESTART)
+#ifdef SA_RESTART
/* SA_RESTART causes interruptible functions with timeouts (e.g.,
'select') to reset their timeout on some platforms (e.g.,
HP-UX 11), which is not what we want. Also, when Emacs is
interactive, we don't want SA_RESTART because we need to poll
for pending input so we need long-running syscalls to be interrupted
- after a signal that sets the interrupt_input_pending flag. */
- /* Non-interactive keyboard input goes through stdio, where we always
- want restartable system calls. */
+ after a signal that sets pending_signals.
+
+ Non-interactive keyboard input goes through stdio, where we
+ always want restartable system calls. */
if (noninteractive)
- action->sa_flags = SA_RESTART;
+ return SA_RESTART;
#endif
+ return 0;
+}
+
+/* Store into *ACTION a signal action suitable for Emacs, with handler
+ HANDLER. */
+void
+emacs_sigaction_init (struct sigaction *action, signal_handler_t handler)
+{
+ sigemptyset (&action->sa_mask);
+
+ /* When handling a signal, block nonfatal system signals that are caught
+ by Emacs. This makes race conditions less likely. */
+ sigaddset (&action->sa_mask, SIGALRM);
+#ifdef SIGCHLD
+ sigaddset (&action->sa_mask, SIGCHLD);
+#endif
+#ifdef SIGDANGER
+ sigaddset (&action->sa_mask, SIGDANGER);
+#endif
+#ifdef SIGWINCH
+ sigaddset (&action->sa_mask, SIGWINCH);
+#endif
+ if (! noninteractive)
+ {
+ sigaddset (&action->sa_mask, SIGINT);
+ sigaddset (&action->sa_mask, SIGQUIT);
+#ifdef USABLE_SIGIO
+ sigaddset (&action->sa_mask, SIGIO);
+#endif
+ }
+
+ if (! IEEE_FLOATING_POINT)
+ sigaddset (&action->sa_mask, SIGFPE);
+
+ action->sa_handler = handler;
+ action->sa_flags = emacs_sigaction_flags ();
}
#ifdef FORWARD_SIGNAL_TO_MAIN_THREAD
static pthread_t main_thread;
#endif
-/* If we are on the main thread, handle the signal SIG with HANDLER.
+/* SIG has arrived at the current process. Deliver it to the main
+ thread, which should handle it with HANDLER.
+
+ If we are on the main thread, handle the signal SIG with HANDLER.
Otherwise, redirect the signal to the main thread, blocking it from
this thread. POSIX says any thread can receive a signal that is
associated with a process, process group, or asynchronous event.
On GNU/Linux that is not true, but for other systems (FreeBSD at
least) it is. */
void
-handle_on_main_thread (int sig, signal_handler_t handler)
+deliver_process_signal (int sig, signal_handler_t handler)
{
/* Preserve errno, to avoid race conditions with signal handlers that
might change errno. Races can occur even in single-threaded hosts. */
errno = old_errno;
}
+
+/* Static location to save a fatal backtrace in a thread.
+ FIXME: If two subsidiary threads fail simultaneously, the resulting
+ backtrace may be garbage. */
+enum { BACKTRACE_LIMIT_MAX = 500 };
+static void *thread_backtrace_buffer[BACKTRACE_LIMIT_MAX + 1];
+static int thread_backtrace_npointers;
+
+/* SIG has arrived at the current thread.
+ If we are on the main thread, handle the signal SIG with HANDLER.
+ Otherwise, this is a fatal error in the handling thread. */
+static void
+deliver_thread_signal (int sig, signal_handler_t handler)
+{
+ int old_errno = errno;
+
+#ifdef FORWARD_SIGNAL_TO_MAIN_THREAD
+ if (! pthread_equal (pthread_self (), main_thread))
+ {
+ thread_backtrace_npointers
+ = backtrace (thread_backtrace_buffer, BACKTRACE_LIMIT_MAX);
+ sigaction (sig, &process_fatal_action, 0);
+ pthread_kill (main_thread, sig);
+
+ /* Avoid further damage while the main thread is exiting. */
+ while (1)
+ sigsuspend (&empty_mask);
+ }
+#endif
+
+ handler (sig);
+ errno = old_errno;
+}
\f
#if !defined HAVE_STRSIGNAL && !HAVE_DECL_SYS_SIGLIST
static char *my_sys_siglist[NSIG];
# define sys_siglist my_sys_siglist
#endif
+/* Handle bus errors, invalid instruction, etc. */
+static void
+handle_fatal_signal (int sig)
+{
+ terminate_due_to_signal (sig, 10);
+}
+
+static void
+deliver_fatal_signal (int sig)
+{
+ deliver_process_signal (sig, handle_fatal_signal);
+}
+
+static void
+deliver_fatal_thread_signal (int sig)
+{
+ deliver_thread_signal (sig, handle_fatal_signal);
+}
+
+static _Noreturn void
+handle_arith_signal (int sig)
+{
+ pthread_sigmask (SIG_SETMASK, &empty_mask, 0);
+ xsignal0 (Qarith_error);
+}
+
+static void
+deliver_arith_signal (int sig)
+{
+ deliver_thread_signal (sig, handle_arith_signal);
+}
+
+/* Treat SIG as a terminating signal, unless it is already ignored and
+ we are in --batch mode. Among other things, this makes nohup work. */
+static void
+maybe_fatal_sig (int sig)
+{
+ bool catch_sig = !noninteractive;
+ if (!catch_sig)
+ {
+ struct sigaction old_action;
+ sigaction (sig, 0, &old_action);
+ catch_sig = old_action.sa_handler != SIG_IGN;
+ }
+ if (catch_sig)
+ sigaction (sig, &process_fatal_action, 0);
+}
+
void
-init_signals (void)
+init_signals (bool dumping)
{
+ struct sigaction thread_fatal_action;
+ struct sigaction action;
+
sigemptyset (&empty_mask);
#ifdef FORWARD_SIGNAL_TO_MAIN_THREAD
#if !defined HAVE_STRSIGNAL && !HAVE_DECL_SYS_SIGLIST
if (! initialized)
{
-# ifdef SIGABRT
sys_siglist[SIGABRT] = "Aborted";
-# endif
# ifdef SIGAIO
sys_siglist[SIGAIO] = "LAN I/O interrupt";
# endif
# ifdef SIGEMT
sys_siglist[SIGEMT] = "Emulation trap";
# endif
-# ifdef SIGFPE
sys_siglist[SIGFPE] = "Arithmetic exception";
-# endif
# ifdef SIGFREEZE
sys_siglist[SIGFREEZE] = "SIGFREEZE";
# endif
# ifdef SIGHUP
sys_siglist[SIGHUP] = "Hangup";
# endif
-# ifdef SIGILL
sys_siglist[SIGILL] = "Illegal instruction";
-# endif
-# ifdef SIGINT
sys_siglist[SIGINT] = "Interrupt";
-# endif
# ifdef SIGIO
sys_siglist[SIGIO] = "I/O possible";
# endif
# ifdef SIGSAK
sys_siglist[SIGSAK] = "Secure attention";
# endif
-# ifdef SIGSEGV
sys_siglist[SIGSEGV] = "Segmentation violation";
-# endif
# ifdef SIGSOUND
sys_siglist[SIGSOUND] = "Sound completed";
# endif
# ifdef SIGSYS
sys_siglist[SIGSYS] = "Bad argument to system call";
# endif
-# ifdef SIGTERM
sys_siglist[SIGTERM] = "Terminated";
-# endif
# ifdef SIGTHAW
sys_siglist[SIGTHAW] = "SIGTHAW";
# endif
# endif
}
#endif /* !defined HAVE_STRSIGNAL && !defined HAVE_DECL_SYS_SIGLIST */
+
+ /* Don't alter signal handlers if dumping. On some machines,
+ changing signal handlers sets static data that would make signals
+ fail to work right when the dumped Emacs is run. */
+ if (dumping)
+ return;
+
+ sigfillset (&process_fatal_action.sa_mask);
+ process_fatal_action.sa_handler = deliver_fatal_signal;
+ process_fatal_action.sa_flags = emacs_sigaction_flags () | SA_NODEFER;
+
+ sigfillset (&thread_fatal_action.sa_mask);
+ thread_fatal_action.sa_handler = deliver_fatal_thread_signal;
+ thread_fatal_action.sa_flags = process_fatal_action.sa_flags;
+
+ /* SIGINT may need special treatment on MS-Windows. See
+ http://lists.gnu.org/archive/html/emacs-devel/2010-09/msg01062.html
+ Please update the doc of kill-emacs, kill-emacs-hook, and
+ NEWS if you change this. */
+
+ maybe_fatal_sig (SIGHUP);
+ maybe_fatal_sig (SIGINT);
+ maybe_fatal_sig (SIGTERM);
+
+ /* Emacs checks for write errors, so it can safely ignore SIGPIPE.
+ However, in batch mode leave SIGPIPE alone, as that causes Emacs
+ to behave more like typical batch applications do. */
+ if (! noninteractive)
+ signal (SIGPIPE, SIG_IGN);
+
+ sigaction (SIGQUIT, &process_fatal_action, 0);
+ sigaction (SIGILL, &thread_fatal_action, 0);
+ sigaction (SIGTRAP, &thread_fatal_action, 0);
+
+ /* Typically SIGFPE is thread-specific and is fatal, like SIGILL.
+ But on a non-IEEE host SIGFPE can come from a trap in the Lisp
+ interpreter's floating point operations, so treat SIGFPE as an
+ arith-error if it arises in the main thread. */
+ if (IEEE_FLOATING_POINT)
+ sigaction (SIGFPE, &thread_fatal_action, 0);
+ else
+ {
+ emacs_sigaction_init (&action, deliver_arith_signal);
+ sigaction (SIGFPE, &action, 0);
+ }
+
+#ifdef SIGUSR1
+ add_user_signal (SIGUSR1, "sigusr1");
+#endif
+#ifdef SIGUSR2
+ add_user_signal (SIGUSR2, "sigusr2");
+#endif
+ sigaction (SIGABRT, &thread_fatal_action, 0);
+#ifdef SIGPRE
+ sigaction (SIGPRE, &thread_fatal_action, 0);
+#endif
+#ifdef SIGORE
+ sigaction (SIGORE, &thread_fatal_action, 0);
+#endif
+#ifdef SIGUME
+ sigaction (SIGUME, &thread_fatal_action, 0);
+#endif
+#ifdef SIGDLK
+ sigaction (SIGDLK, &process_fatal_action, 0);
+#endif
+#ifdef SIGCPULIM
+ sigaction (SIGCPULIM, &process_fatal_action, 0);
+#endif
+#ifdef SIGIOT
+ sigaction (SIGIOT, &thread_fatal_action, 0);
+#endif
+#ifdef SIGEMT
+ sigaction (SIGEMT, &thread_fatal_action, 0);
+#endif
+#ifdef SIGBUS
+ sigaction (SIGBUS, &thread_fatal_action, 0);
+#endif
+ sigaction (SIGSEGV, &thread_fatal_action, 0);
+#ifdef SIGSYS
+ sigaction (SIGSYS, &thread_fatal_action, 0);
+#endif
+ sigaction (SIGTERM, &process_fatal_action, 0);
+#ifdef SIGPROF
+ sigaction (SIGPROF, &process_fatal_action, 0);
+#endif
+#ifdef SIGVTALRM
+ sigaction (SIGVTALRM, &process_fatal_action, 0);
+#endif
+#ifdef SIGXCPU
+ sigaction (SIGXCPU, &process_fatal_action, 0);
+#endif
+#ifdef SIGXFSZ
+ sigaction (SIGXFSZ, &process_fatal_action, 0);
+#endif
+
+#ifdef SIGDANGER
+ /* This just means available memory is getting low. */
+ emacs_sigaction_init (&action, deliver_danger_signal);
+ sigaction (SIGDANGER, &action, 0);
+#endif
+
+ /* AIX-specific signals. */
+#ifdef SIGGRANT
+ sigaction (SIGGRANT, &process_fatal_action, 0);
+#endif
+#ifdef SIGMIGRATE
+ sigaction (SIGMIGRATE, &process_fatal_action, 0);
+#endif
+#ifdef SIGMSG
+ sigaction (SIGMSG, &process_fatal_action, 0);
+#endif
+#ifdef SIGRETRACT
+ sigaction (SIGRETRACT, &process_fatal_action, 0);
+#endif
+#ifdef SIGSAK
+ sigaction (SIGSAK, &process_fatal_action, 0);
+#endif
+#ifdef SIGSOUND
+ sigaction (SIGSOUND, &process_fatal_action, 0);
+#endif
+#ifdef SIGTALRM
+ sigaction (SIGTALRM, &thread_fatal_action, 0);
+#endif
}
\f
#ifndef HAVE_RANDOM
void
emacs_backtrace (int backtrace_limit)
{
- enum { BACKTRACE_LIMIT_MAX = 500 };
- void *buffer[BACKTRACE_LIMIT_MAX + 1];
+ void *main_backtrace_buffer[BACKTRACE_LIMIT_MAX + 1];
int bounded_limit = min (backtrace_limit, BACKTRACE_LIMIT_MAX);
- int npointers = backtrace (buffer, bounded_limit + 1);
+ void *buffer;
+ int npointers;
+
+ if (thread_backtrace_npointers)
+ {
+ buffer = thread_backtrace_buffer;
+ npointers = thread_backtrace_npointers;
+ }
+ else
+ {
+ buffer = main_backtrace_buffer;
+ npointers = backtrace (buffer, bounded_limit + 1);
+ }
+
if (npointers)
- ignore_value (write (STDERR_FILENO, "\nBacktrace:\n", 12));
- backtrace_symbols_fd (buffer, bounded_limit, STDERR_FILENO);
- if (bounded_limit < npointers)
- ignore_value (write (STDERR_FILENO, "...\n", 4));
+ {
+ ignore_value (write (STDERR_FILENO, "\nBacktrace:\n", 12));
+ backtrace_symbols_fd (buffer, npointers, STDERR_FILENO);
+ if (bounded_limit < npointers)
+ ignore_value (write (STDERR_FILENO, "...\n", 4));
+ }
}
\f
#ifndef HAVE_NTGUI
-/* Using emacs_abort lets GDB return from a breakpoint here. */
void
emacs_abort (void)
{
- fatal_error_backtrace (SIGABRT, 10);
+ signal (SIGABRT, SIG_DFL);
+ terminate_due_to_signal (SIGABRT, 10);
}
#endif
{
/* I originally used `QUIT' but that might causes files to
be truncated if you hit C-g in the middle of it. --Stef */
- process_pending_signals ();
+ if (pending_signals)
+ process_pending_signals ();
continue;
}
else
char *npath, *spath;
extern char *getcwd (char *, size_t);
- BLOCK_INPUT; /* getcwd uses malloc */
+ block_input (); /* getcwd uses malloc */
spath = npath = getcwd ((char *) 0, MAXPATHLEN);
if (spath == 0)
{
- UNBLOCK_INPUT;
+ unblock_input ();
return spath;
}
/* On Altos 3068, getcwd can return @hostname/dir, so discard
npath++;
strcpy (pathname, npath);
free (spath); /* getcwd uses malloc */
- UNBLOCK_INPUT;
+ unblock_input ();
return pathname;
}
FILE *fup;
EMACS_TIME up = make_emacs_time (0, 0);
- BLOCK_INPUT;
+ block_input ();
fup = fopen ("/proc/uptime", "r");
if (fup)
}
fclose (fup);
}
- UNBLOCK_INPUT;
+ unblock_input ();
return up;
}
FILE *fdev = NULL;
char name[PATH_MAX];
- BLOCK_INPUT;
+ block_input ();
fdev = fopen ("/proc/tty/drivers", "r");
if (fdev)
}
fclose (fdev);
}
- UNBLOCK_INPUT;
+ unblock_input ();
return build_string (name);
}
FILE *fmem = NULL;
unsigned long retval = 2 * 1024 * 1024; /* default: 2GB */
- BLOCK_INPUT;
+ block_input ();
fmem = fopen ("/proc/meminfo", "r");
if (fmem)
}
fclose (fmem);
}
- UNBLOCK_INPUT;
+ unblock_input ();
return retval;
}
/* euid egid */
uid = st.st_uid;
attrs = Fcons (Fcons (Qeuid, make_fixnum_or_float (uid)), attrs);
- BLOCK_INPUT;
+ block_input ();
pw = getpwuid (uid);
- UNBLOCK_INPUT;
+ unblock_input ();
if (pw)
attrs = Fcons (Fcons (Quser, build_string (pw->pw_name)), attrs);
gid = st.st_gid;
attrs = Fcons (Fcons (Qegid, make_fixnum_or_float (gid)), attrs);
- BLOCK_INPUT;
+ block_input ();
gr = getgrgid (gid);
- UNBLOCK_INPUT;
+ unblock_input ();
if (gr)
attrs = Fcons (Fcons (Qgroup, build_string (gr->gr_name)), attrs);
/* euid egid */
uid = st.st_uid;
attrs = Fcons (Fcons (Qeuid, make_fixnum_or_float (uid)), attrs);
- BLOCK_INPUT;
+ block_input ();
pw = getpwuid (uid);
- UNBLOCK_INPUT;
+ unblock_input ();
if (pw)
attrs = Fcons (Fcons (Quser, build_string (pw->pw_name)), attrs);
gid = st.st_gid;
attrs = Fcons (Fcons (Qegid, make_fixnum_or_float (gid)), attrs);
- BLOCK_INPUT;
+ block_input ();
gr = getgrgid (gid);
- UNBLOCK_INPUT;
+ unblock_input ();
if (gr)
attrs = Fcons (Fcons (Qgroup, build_string (gr->gr_name)), attrs);
attrs = Fcons (Fcons (Qeuid, make_fixnum_or_float (proc.ki_uid)), attrs);
- BLOCK_INPUT;
+ block_input ();
pw = getpwuid (proc.ki_uid);
- UNBLOCK_INPUT;
+ unblock_input ();
if (pw)
attrs = Fcons (Fcons (Quser, build_string (pw->pw_name)), attrs);
attrs = Fcons (Fcons (Qegid, make_fixnum_or_float (proc.ki_svgid)), attrs);
- BLOCK_INPUT;
+ block_input ();
gr = getgrgid (proc.ki_svgid);
- UNBLOCK_INPUT;
+ unblock_input ();
if (gr)
attrs = Fcons (Fcons (Qgroup, build_string (gr->gr_name)), attrs);
attrs = Fcons (Fcons (Qpgrp, make_fixnum_or_float (proc.ki_pgid)), attrs);
attrs = Fcons (Fcons (Qsess, make_fixnum_or_float (proc.ki_sid)), attrs);
- BLOCK_INPUT;
+ block_input ();
ttyname = proc.ki_tdev == NODEV ? NULL : devname (proc.ki_tdev, S_IFCHR);
- UNBLOCK_INPUT;
+ unblock_input ();
if (ttyname)
attrs = Fcons (Fcons (Qtty, build_string (ttyname)), attrs);
HCoop / bpt / emacs.git / blobdiff