add signal handler

diff --git a/signal.c b/signal.c
new file mode 100644 (file)
index 0000000..a4b08c3
--- /dev/null
+++ b/signal.c
@@ -0,0 +1,88 @@
+/*
+ * Copyright (C) 2013 Felix Fietkau <nbd@openwrt.org>
+ * Copyright (C) 2013 John Crispin <blogic@openwrt.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1
+ * as published by the Free Software Foundation
+ *
+ * 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.
+ */
+
+#include <sys/reboot.h>
+#include <sys/types.h>
+
+#include <unistd.h>
+
+#include "procd.h"
+
+static void signal_shutdown(int signal, siginfo_t *siginfo, void *data)
+{
+       int event = 0;
+       char *msg = NULL;
+
+       switch(signal) {
+       case SIGTERM:
+               event = RB_AUTOBOOT;
+               msg = "reboot";
+               break;
+       case SIGUSR1:
+       case SIGUSR2:
+               event = RB_POWER_OFF;
+               msg = "poweroff";
+               break;
+       }
+
+       DEBUG(1, "Triggering %s\n", msg);
+       if (event)
+               procd_shutdown(event);
+}
+
+struct sigaction sa_shutdown = {
+       .sa_sigaction = signal_shutdown,
+       .sa_flags = SA_SIGINFO
+};
+
+static void signal_crash(int signal, siginfo_t *siginfo, void *data)
+{
+       ERROR("Rebooting as procd has crashed\n");
+       fflush(stderr);
+       sync();
+       sleep(1);
+       reboot(RB_AUTOBOOT);
+       while (1)
+               ;
+}
+
+struct sigaction sa_crash = {
+       .sa_sigaction = signal_crash,
+       .sa_flags = SA_SIGINFO
+};
+
+static void signal_dummy(int signal, siginfo_t *siginfo, void *data)
+{
+       ERROR("Got unexpected signal %d\n", signal);
+}
+
+struct sigaction sa_dummy = {
+       .sa_sigaction = signal_dummy,
+       .sa_flags = SA_SIGINFO
+};
+
+void procd_signal(void)
+{
+       sigaction(SIGPIPE, &sa_dummy, NULL);
+       if (getpid() != 1)
+               return;
+       sigaction(SIGTERM, &sa_shutdown, NULL);
+       sigaction(SIGUSR1, &sa_shutdown, NULL);
+       sigaction(SIGUSR2, &sa_shutdown, NULL);
+       sigaction(SIGSEGV, &sa_crash, NULL);
+       sigaction(SIGBUS, &sa_crash, NULL);
+       sigaction(SIGHUP, &sa_dummy, NULL);
+       sigaction(SIGKILL, &sa_dummy, NULL);
+       sigaction(SIGSTOP, &sa_dummy, NULL);
+}