/**
* Signal handler
*
* @param signr Signal type
*/
static void signal_handler(const gint signr)
{
switch (signr) {
case SIGUSR1:
/* We'll probably want some way to communicate with MCE */
break;
case SIGHUP:
/* Possibly for re-reading configuration? */
break;
case SIGINT:
case SIGQUIT:
case SIGTERM:
/* Just die if we somehow get here without having a mainloop */
if( !mainloop ) {
mce_exit_via_signal(signr);
}
/* Terminate mainloop */
mce_quit_mainloop();
break;
case SIGPIPE:
break;
default:
/* Should never happen */
break;
}
}
/** Signal handler callback for writing signals to pipe
*
* @param sig the signal number to pass to mainloop via pipe
*/
static void mce_tx_signal_cb(int sig)
{
/* NOTE: this function must be kept async-signal-safe! */
static volatile int exit_tries = 0;
static const char msg[] = "\n*** BREAK ***\n";
static const char die[] = "\n*** UNRECOVERABLE FAILURE ***\n";
switch( sig )
{
case SIGUSR1:
case SIGUSR2:
case SIGHUP:
/* Just pass to mainloop */
break;
case SIGINT:
case SIGQUIT:
case SIGTERM:
/* Make sure that a stuck or non-existing mainloop does
* not stop us from handling at least repeated terminating
signals ... */
#ifdef ENABLE_WAKELOCKS
/* We are on exit path -> block suspend for good */
wakelock_block_suspend_until_exit();
#endif
no_error_check_write(STDERR_FILENO, msg, sizeof msg - 1);
if( !mainloop || ++exit_tries >= 2 ) {
mce_abort();
}
break;
default:
/* Assume unrecoverable failure that can't be handled in
* the mainloop - disable autosuspend and then terminate
* via default signal handler. */
no_error_check_write(STDERR_FILENO, die, sizeof die - 1);
mce_exit_via_signal(sig);
break;
}
/* transfer the signal to mainloop via pipe */
int did = TEMP_FAILURE_RETRY(write(signal_pipe[1], &sig, sizeof sig));
if( did != (int)sizeof sig ) {
mce_abort();
}
}
/**
* Signal handler
*
* @param signr Signal type
*/
static void signal_handler(const gint signr)
{
switch (signr) {
case SIGUSR1:
/* switch to debug verbosity */
mce_log_set_verbosity(LL_DEBUG);
mce_log(LL_DEBUG, "switching to DEBUG verbosity level");
break;
case SIGUSR2:
/* switch to normal verbosity */
mce_log_set_verbosity(LL_DEBUG);
mce_log(LL_DEBUG, "switching to WARNING verbosity level");
mce_log_set_verbosity(LL_WARN);
break;
case SIGHUP:
/* Possibly for re-reading configuration? */
break;
case SIGINT:
case SIGQUIT:
case SIGTERM:
/* Just die if we somehow get here without having a mainloop */
if( !mainloop ) {
mce_exit_via_signal(signr);
}
/* Terminate mainloop */
mce_quit_mainloop();
break;
case SIGPIPE:
break;
default:
/* Should never happen */
break;
}
}
/** Suspend safe replacement for _exit(1), abort() etc
*/
void mce_abort(void)
{
mce_exit_via_signal(SIGABRT);
}
/** Signal handler callback for writing signals to pipe
*
* @param sig the signal number to pass to mainloop via pipe
*/
static void mce_tx_signal_cb(int sig)
{
/* NOTE: this function must be kept async-signal-safe! */
static volatile int exit_tries = 0;
static const char msg[] = "\n*** BREAK ***\n";
#ifdef ENABLE_WAKELOCKS
static const char die[] = "\n*** UNRECOVERABLE FAILURE ***\n";
#endif
/* FIXME: Should really use sigaction() to avoid having
* the default handler active until we manage to restore
* our handler here ... */
signal(sig, mce_tx_signal_cb);
switch( sig )
{
case SIGINT:
case SIGQUIT:
case SIGTERM:
/* Make sure that a stuck or non-existing mainloop does
* not stop us from handling at least repeated terminating
signals ... */
#ifdef ENABLE_WAKELOCKS
/* We are on exit path -> block suspend for good */
wakelock_block_suspend_until_exit();
#endif
no_error_check_write(STDERR_FILENO, msg, sizeof msg - 1);
if( !mainloop || ++exit_tries >= 2 ) {
mce_abort();
}
break;
#ifdef ENABLE_WAKELOCKS
case SIGABRT:
case SIGILL:
case SIGFPE:
case SIGSEGV:
case SIGALRM:
case SIGBUS:
/* Unrecoverable failures can't be handled in the mainloop
* Terminate but disable suspend first */
no_error_check_write(STDERR_FILENO, die, sizeof die - 1);
mce_exit_via_signal(sig);
break;
case SIGTSTP:
/* Stopping mce could also lead to unrecoverable suspend */
break;
#endif
default:
break;
}
/* transfer the signal to mainloop via pipe */
int did = TEMP_FAILURE_RETRY(write(signal_pipe[1], &sig, sizeof sig));
if( did != (int)sizeof sig ) {
mce_abort();
}
}
