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Cleanup signal handling.
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SIGTSTP should not redirect you to the internal signal handler but just
use the normal signal handling e.g. stop the process.
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Marco van Wieringen committed Feb 17, 2015
1 parent ba80259 commit c1341bb
Showing 1 changed file with 103 additions and 89 deletions.
192 changes: 103 additions & 89 deletions src/lib/signal.c
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Expand Up @@ -45,7 +45,7 @@ extern char *exepath;
extern char *exename;
extern bool prt_kaboom;

static const char *sig_names[BA_NSIG+1];
static const char *sig_names[BA_NSIG + 1];

typedef void (SIG_HANDLER)(int sig);
static SIG_HANDLER *exit_handler;
Expand Down Expand Up @@ -127,23 +127,31 @@ extern "C" void signal_handler(int sig)
static int already_dead = 0;
int chld_status = -1;

/* If we come back more than once, get out fast! */
/*
* If we come back more than once, get out fast!
*/
if (already_dead) {
exit(1);
}
Dmsg2(900, "sig=%d %s\n", sig, sig_names[sig]);
/* Ignore certain signals -- SIGUSR2 used to interrupt threads */

/*
* Ignore certain signals -- SIGUSR2 used to interrupt threads
*/
if (sig == SIGCHLD || sig == SIGUSR2) {
return;
}
already_dead++;
/* Don't use Emsg here as it may lock and thus block us */

/*
* Don't use Emsg here as it may lock and thus block us
*/
if (sig == SIGTERM) {
syslog(LOG_DAEMON|LOG_ERR, "Shutting down BAREOS service: %s ...\n", my_name);
syslog(LOG_DAEMON | LOG_ERR, "Shutting down BAREOS service: %s ...\n", my_name);
} else {
fprintf(stderr, _("BAREOS interrupted by signal %d: %s\n"), sig, get_signal_name(sig));
syslog(LOG_DAEMON|LOG_ERR,
_("BAREOS interrupted by signal %d: %s\n"), sig, get_signal_name(sig));
syslog(LOG_DAEMON | LOG_ERR,
_("BAREOS interrupted by signal %d: %s\n"), sig, get_signal_name(sig));
}

#ifdef TRACEBACK
Expand Down Expand Up @@ -188,7 +196,9 @@ extern "C" void signal_handler(int sig)
unlink("./core"); /* get rid of any old core file */

#ifdef DEVELOPER /* When DEVELOPER not set, this is done below */
/* print information about the current state into working/<file>.bactrace */
/*
* Print information about the current state into working/<file>.bactrace
*/
dbg_print_bareos();
#endif

Expand Down Expand Up @@ -217,12 +227,14 @@ extern "C" void signal_handler(int sig)
break;
}

/* Parent continue here, waiting for child */
/*
* Parent continue here, waiting for child
*/
sigdefault.sa_flags = 0;
sigdefault.sa_handler = SIG_DFL;
sigfillset(&sigdefault.sa_mask);

sigaction(sig, &sigdefault, NULL);
sigaction(sig, &sigdefault, NULL);
if (pid > 0) {
Dmsg0(500, "Doing waitpid\n");
waitpid(pid, &chld_status, 0); /* wait for child to produce dump */
Expand All @@ -235,13 +247,16 @@ extern "C" void signal_handler(int sig)
fprintf(stderr, _("It looks like the traceback worked...\n"));
} else {
fprintf(stderr, _("The btraceback call returned %d\n"),
WEXITSTATUS(chld_status));
WEXITSTATUS(chld_status));
}

/* If we want it printed, do so */
/*
* If we want it printed, do so
*/
#ifdef direct_print
if (prt_kaboom) {
FILE *fd;

snprintf(buf, sizeof(buf), "%s/bareos.%s.traceback", working_directory, pid_buf);
fd = fopen(buf, "r");
if (fd != NULL) {
Expand All @@ -263,7 +278,9 @@ extern "C" void signal_handler(int sig)
#endif

#ifndef DEVELOPER /* When DEVELOPER set, this is done above */
/* print information about the current state into working/<file>.bactrace */
/*
* Print information about the current state into working/<file>.bactrace
*/
dbg_print_bareos();
#endif

Expand All @@ -274,8 +291,7 @@ extern "C" void signal_handler(int sig)
}

/*
* Init stack dump by saving main process id --
* needed by debugger to attach to this program.
* Init stack dump by saving main process id -- needed by debugger to attach to this program.
*/
void init_stack_dump(void)
{
Expand All @@ -294,76 +310,79 @@ void init_signals(void terminate(int sig))
int i;

exit_handler = terminate;
if (BA_NSIG < _sys_nsig)
if (BA_NSIG < _sys_nsig) {
Emsg2(M_ABORT, 0, _("BA_NSIG too small (%d) should be (%d)\n"), BA_NSIG, _sys_nsig);
}

for (i=0; i<_sys_nsig; i++)
for (i = 0; i < _sys_nsig; i++) {
sig_names[i] = _sys_siglist[i];
}
#else
exit_handler = terminate;
sig_names[0] = _("UNKNOWN SIGNAL");
sig_names[SIGHUP] = _("Hangup");
sig_names[SIGINT] = _("Interrupt");
sig_names[SIGQUIT] = _("Quit");
sig_names[SIGILL] = _("Illegal instruction");
sig_names[SIGTRAP] = _("Trace/Breakpoint trap");
sig_names[SIGABRT] = _("Abort");
sig_names[0] = _("UNKNOWN SIGNAL");
sig_names[SIGHUP] = _("Hangup");
sig_names[SIGINT] = _("Interrupt");
sig_names[SIGQUIT] = _("Quit");
sig_names[SIGILL] = _("Illegal instruction");
sig_names[SIGTRAP] = _("Trace/Breakpoint trap");
sig_names[SIGABRT] = _("Abort");
#ifdef SIGEMT
sig_names[SIGEMT] = _("EMT instruction (Emulation Trap)");
sig_names[SIGEMT] = _("EMT instruction (Emulation Trap)");
#endif
#ifdef SIGIOT
sig_names[SIGIOT] = _("IOT trap");
sig_names[SIGIOT] = _("IOT trap");
#endif
sig_names[SIGBUS] = _("BUS error");
sig_names[SIGFPE] = _("Floating-point exception");
sig_names[SIGKILL] = _("Kill, unblockable");
sig_names[SIGUSR1] = _("User-defined signal 1");
sig_names[SIGSEGV] = _("Segmentation violation");
sig_names[SIGUSR2] = _("User-defined signal 2");
sig_names[SIGPIPE] = _("Broken pipe");
sig_names[SIGALRM] = _("Alarm clock");
sig_names[SIGTERM] = _("Termination");
sig_names[SIGBUS] = _("BUS error");
sig_names[SIGFPE] = _("Floating-point exception");
sig_names[SIGKILL] = _("Kill, unblockable");
sig_names[SIGUSR1] = _("User-defined signal 1");
sig_names[SIGSEGV] = _("Segmentation violation");
sig_names[SIGUSR2] = _("User-defined signal 2");
sig_names[SIGPIPE] = _("Broken pipe");
sig_names[SIGALRM] = _("Alarm clock");
sig_names[SIGTERM] = _("Termination");
#ifdef SIGSTKFLT
sig_names[SIGSTKFLT] = _("Stack fault");
#endif
sig_names[SIGCHLD] = _("Child status has changed");
sig_names[SIGCONT] = _("Continue");
sig_names[SIGSTOP] = _("Stop, unblockable");
sig_names[SIGTSTP] = _("Keyboard stop");
sig_names[SIGTTIN] = _("Background read from tty");
sig_names[SIGTTOU] = _("Background write to tty");
sig_names[SIGURG] = _("Urgent condition on socket");
sig_names[SIGXCPU] = _("CPU limit exceeded");
sig_names[SIGXFSZ] = _("File size limit exceeded");
sig_names[SIGCHLD] = _("Child status has changed");
sig_names[SIGCONT] = _("Continue");
sig_names[SIGSTOP] = _("Stop, unblockable");
sig_names[SIGTSTP] = _("Keyboard stop");
sig_names[SIGTTIN] = _("Background read from tty");
sig_names[SIGTTOU] = _("Background write to tty");
sig_names[SIGURG] = _("Urgent condition on socket");
sig_names[SIGXCPU] = _("CPU limit exceeded");
sig_names[SIGXFSZ] = _("File size limit exceeded");
sig_names[SIGVTALRM] = _("Virtual alarm clock");
sig_names[SIGPROF] = _("Profiling alarm clock");
sig_names[SIGWINCH] = _("Window size change");
sig_names[SIGIO] = _("I/O now possible");
sig_names[SIGPROF] = _("Profiling alarm clock");
sig_names[SIGWINCH] = _("Window size change");
sig_names[SIGIO] = _("I/O now possible");
#ifdef SIGPWR
sig_names[SIGPWR] = _("Power failure restart");
sig_names[SIGPWR] = _("Power failure restart");
#endif
#ifdef SIGWAITING
sig_names[SIGWAITING] = _("No runnable lwp");
#endif
#ifdef SIGLWP
sig_names[SIGLWP] = _("SIGLWP special signal used by thread library");
sig_names[SIGLWP] = _("SIGLWP special signal used by thread library");
#endif
#ifdef SIGFREEZE
sig_names[SIGFREEZE] = _("Checkpoint Freeze");
#endif
#ifdef SIGTHAW
sig_names[SIGTHAW] = _("Checkpoint Thaw");
sig_names[SIGTHAW] = _("Checkpoint Thaw");
#endif
#ifdef SIGCANCEL
sig_names[SIGCANCEL] = _("Thread Cancellation");
#endif
#ifdef SIGLOST
sig_names[SIGLOST] = _("Resource Lost (e.g. record-lock lost)");
sig_names[SIGLOST] = _("Resource Lost (e.g. record-lock lost)");
#endif
#endif


/* Now setup signal handlers */
/*
* Now setup signal handlers
*/
sighandle.sa_flags = 0;
sighandle.sa_handler = signal_handler;
sigfillset(&sighandle.sa_mask);
Expand All @@ -374,66 +393,61 @@ void init_signals(void terminate(int sig))
sigdefault.sa_handler = SIG_DFL;
sigfillset(&sigdefault.sa_mask);


sigaction(SIGPIPE, &sigignore, NULL);
sigaction(SIGCHLD, &sighandle, NULL);
sigaction(SIGCONT, &sigignore, NULL);
sigaction(SIGPROF, &sigignore, NULL);
sigaction(SIGWINCH, &sigignore, NULL);
sigaction(SIGIO, &sighandle, NULL);

sigaction(SIGINT, &sigdefault, NULL);
sigaction(SIGXCPU, &sigdefault, NULL);
sigaction(SIGXFSZ, &sigdefault, NULL);

sigaction(SIGHUP, &sigignore, NULL);
sigaction(SIGQUIT, &sighandle, NULL);
sigaction(SIGILL, &sighandle, NULL);
sigaction(SIGTRAP, &sighandle, NULL);
sigaction(SIGABRT, &sighandle, NULL);
sigaction(SIGPIPE, &sigignore, NULL);
sigaction(SIGCHLD, &sighandle, NULL);
sigaction(SIGCONT, &sigignore, NULL);
sigaction(SIGPROF, &sigignore, NULL);
sigaction(SIGWINCH, &sigignore, NULL);
sigaction(SIGIO, &sighandle, NULL);
sigaction(SIGINT, &sigdefault, NULL);
sigaction(SIGXCPU, &sigdefault, NULL);
sigaction(SIGXFSZ, &sigdefault, NULL);
sigaction(SIGHUP, &sigignore, NULL);
sigaction(SIGQUIT, &sighandle, NULL);
sigaction(SIGILL, &sighandle, NULL);
sigaction(SIGTRAP, &sighandle, NULL);
sigaction(SIGABRT, &sighandle, NULL);
#ifdef SIGEMT
sigaction(SIGEMT, &sighandle, NULL);
sigaction(SIGEMT, &sighandle, NULL);
#endif
#ifdef SIGIOT
sigaction(SIGIOT, &sighandle, NULL);
sigaction(SIGIOT, &sighandle, NULL);
#endif
sigaction(SIGBUS, &sighandle, NULL);
sigaction(SIGFPE, &sighandle, NULL);
/* sigaction(SIGKILL, &sighandle, NULL); cannot be trapped */
sigaction(SIGUSR1, &sighandle, NULL);
sigaction(SIGSEGV, &sighandle, NULL);
sigaction(SIGUSR2, &sighandle, NULL);
sigaction(SIGALRM, &sighandle, NULL);
sigaction(SIGTERM, &sighandle, NULL);
sigaction(SIGBUS, &sighandle, NULL);
sigaction(SIGFPE, &sighandle, NULL);
sigaction(SIGUSR1, &sighandle, NULL);
sigaction(SIGSEGV, &sighandle, NULL);
sigaction(SIGUSR2, &sighandle, NULL);
sigaction(SIGALRM, &sighandle, NULL);
sigaction(SIGTERM, &sighandle, NULL);
#ifdef SIGSTKFLT
sigaction(SIGSTKFLT, &sighandle, NULL);
#endif
/* sigaction(SIGSTOP, &sighandle, NULL); cannot be trapped */
sigaction(SIGTSTP, &sighandle, NULL);
sigaction(SIGTTIN, &sighandle, NULL);
sigaction(SIGTTOU, &sighandle, NULL);
sigaction(SIGURG, &sighandle, NULL);
sigaction(SIGTSTP, &sigdefault, NULL);
sigaction(SIGTTIN, &sighandle, NULL);
sigaction(SIGTTOU, &sighandle, NULL);
sigaction(SIGURG, &sighandle, NULL);
sigaction(SIGVTALRM, &sighandle, NULL);
#ifdef SIGPWR
sigaction(SIGPWR, &sighandle, NULL);
sigaction(SIGPWR, &sighandle, NULL);
#endif
#ifdef SIGWAITING
sigaction(SIGWAITING,&sighandle, NULL);
#endif
#ifdef SIGLWP
sigaction(SIGLWP, &sighandle, NULL);
sigaction(SIGLWP, &sighandle, NULL);
#endif
#ifdef SIGFREEZE
sigaction(SIGFREEZE, &sighandle, NULL);
#endif
#ifdef SIGTHAW
sigaction(SIGTHAW, &sighandle, NULL);
sigaction(SIGTHAW, &sighandle, NULL);
#endif
#ifdef SIGCANCEL
sigaction(SIGCANCEL, &sighandle, NULL);
#endif
#ifdef SIGLOST
sigaction(SIGLOST, &sighandle, NULL);
sigaction(SIGLOST, &sighandle, NULL);
#endif
}
#endif

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