/*
- * Copyright (C) 2017 "IoT.bzh"
+ * Copyright (C) 2017, 2018 "IoT.bzh"
* Author José Bollo <jose.bollo@iot.bzh>
*
* Licensed under the Apache License, Version 2.0 (the "License");
static _Thread_local int thread_timer_set;
static _Thread_local timer_t thread_timerid;
+/* internal signal lists */
+static int sigerr[] = { SIG_FOR_TIMER, SIGSEGV, SIGFPE, SIGILL, SIGBUS, 0 };
+static int sigterm[] = { SIGINT, SIGABRT, SIGTERM, 0 };
+static int exiting = 0;
+static int enabled = 0;
+
/*
* Dumps the current stack
*/
static void safe_dumpstack(int crop, int signum)
{
- int args[2] = { crop, signum };
+ int args[2] = { crop + 3, signum };
in_safe_dumpstack = 1;
sig_monitor(0, safe_dumpstack_cb, args);
}
}
+/* install the handlers */
+static int install(void (*handler)(int), int *signals)
+{
+ int result = 1;
+ struct sigaction sa;
+
+ sa.sa_handler = handler;
+ sigemptyset(&sa.sa_mask);
+ sa.sa_flags = SA_NODEFER;
+ while(*signals > 0) {
+ if (sigaction(*signals, &sa, NULL) < 0) {
+ ERROR("failed to install signal handler for signal %s: %m", strsignal(*signals));
+ result = 0;
+ }
+ signals++;
+ }
+ return result;
+}
+
+/*
+ * rescue exit
+ */
+static void on_rescue_exit(int signum)
+{
+ ERROR("Rescue exit for signal %d: %s", signum, strsignal(signum));
+ _exit(exiting);
+}
+
+/*
+ * Do a safe exit
+ */
+static void safe_exit(int code)
+{
+ install(on_rescue_exit, sigerr);
+ install(on_rescue_exit, sigterm);
+ exiting = code;
+ exit(code);
+}
/* Handles signals that terminate the process */
static void on_signal_terminate (int signum)
if (signum == SIGABRT)
safe_dumpstack(3, signum);
}
- exit(1);
+ safe_exit(1);
}
/* Handles monitored signals that can be continued */
static void on_signal_error(int signum)
{
- sigset_t sigset;
-
if (in_safe_dumpstack)
longjmp(*error_handler, signum);
longjmp(*error_handler, signum);
ERROR("Unmonitored signal %d received: %s", signum, strsignal(signum));
- exit(2);
+ safe_exit(2);
}
-/* install the handlers */
-static int install(void (*handler)(int), int *signals)
+void sig_monitor_disable()
{
- int result = 1;
- struct sigaction sa;
-
- sa.sa_handler = handler;
- sigemptyset(&sa.sa_mask);
- sa.sa_flags = SA_NODEFER;
- while(*signals > 0) {
- if (sigaction(*signals, &sa, NULL) < 0) {
- ERROR("failed to install signal handler for signal %s: %m", strsignal(*signals));
- result = 0;
- }
- signals++;
- }
- return result;
+ enabled = 0;
+ install(SIG_DFL, sigerr);
+ install(SIG_DFL, sigterm);
}
-int sig_monitor_init()
+int sig_monitor_enable()
{
- static int sigerr[] = { SIG_FOR_TIMER, SIGSEGV, SIGFPE, SIGILL, SIGBUS, 0 };
- static int sigterm[] = { SIGINT, SIGABRT, SIGTERM, 0 };
+ enabled = install(on_signal_error, sigerr) && install(on_signal_terminate, sigterm);
+ if (enabled)
+ return 0;
+ sig_monitor_disable();
+ return -1;
+}
- return (install(on_signal_error, sigerr) & install(on_signal_terminate, sigterm)) - 1;
+int sig_monitor_init(int enable)
+{
+ return enable ? sig_monitor_enable() : (sig_monitor_disable(), 0);
}
int sig_monitor_init_timeouts()
timeout_delete();
}
-void sig_monitor(int timeout, void (*function)(int sig, void*), void *arg)
+static void monitor(int timeout, void (*function)(int sig, void*), void *arg)
{
volatile int signum, signum2;
sigjmp_buf jmpbuf, *older;
signum = setjmp(jmpbuf);
if (signum == 0) {
error_handler = &jmpbuf;
- if (timeout)
+ if (timeout) {
+ timeout_create();
timeout_arm(timeout);
+ }
function(0, arg);
} else {
signum2 = setjmp(jmpbuf);
if (signum2 == 0)
function(signum, arg);
}
- error_handler = older;
if (timeout)
timeout_disarm();
+ error_handler = older;
}
+void sig_monitor(int timeout, void (*function)(int sig, void*), void *arg)
+{
+ if (enabled)
+ monitor(timeout, function, arg);
+ else
+ function(0, arg);
+}
+void sig_monitor_dumpstack()
+{
+ return dumpstack(1, 0);
+}