X-Git-Url: https://gerrit.automotivelinux.org/gerrit/gitweb?a=blobdiff_plain;f=src%2Fsig-monitor.c;h=759825073e2737fe91b4d1cd46ac097ff9be6c62;hb=bee892ba769f78ede968ad9b6aea006b6aee26e9;hp=bd1311a9620c75edb521adc258068562c7a29e01;hpb=859e455780dccf2cbe4f2a94a65e4639e6c7e183;p=src%2Fapp-framework-binder.git

diff --git a/src/sig-monitor.c b/src/sig-monitor.c
index bd1311a9..75982507 100644
--- a/src/sig-monitor.c
+++ b/src/sig-monitor.c
@@ -18,6 +18,7 @@
 #define _GNU_SOURCE
 
 #include <stdlib.h>
+#include <stdio.h>
 #include <signal.h>
 #include <string.h>
 #include <setjmp.h>
@@ -33,6 +34,7 @@
 
 /* local handler */
 static _Thread_local sigjmp_buf *error_handler;
+static _Thread_local int in_safe_dumpstack;
 
 /* local timers */
 static _Thread_local int thread_timer_set;
@@ -41,23 +43,57 @@ static _Thread_local timer_t thread_timerid;
 /*
  * Dumps the current stack
  */
-static void dumpstack(int crop)
+static void dumpstack(int crop, int signum)
 {
-	int idx, count;
-	void *addresses[1000];
+	int idx, count, rc;
+	void *addresses[100];
 	char **locations;
+	char buffer[8000];
+	size_t pos, length;
 
 	count = backtrace(addresses, sizeof addresses / sizeof *addresses);
-	locations = backtrace_symbols(addresses, count);
+	if (count <= crop)
+		crop = 0;
+	count -= crop;
+	locations = backtrace_symbols(&addresses[crop], count);
 	if (locations == NULL)
 		ERROR("can't get the backtrace (returned %d addresses)", count);
 	else {
-		for (idx = crop; idx < count; idx++)
-			ERROR("[BACKTRACE %d/%d] %s", idx - crop + 1, count - crop, locations[idx]);
+		length = sizeof buffer - 1;
+		pos = 0;
+		idx = 0;
+		while (pos < length && idx < count) {
+			rc = snprintf(&buffer[pos], length - pos, " [%d/%d] %s\n", idx + 1, count, locations[idx]);
+			pos += rc >= 0 ? rc : 0;
+			idx++;
+		}
+		buffer[length] = 0;
+		if (signum)
+			ERROR("BACKTRACE due to signal %s/%d:\n%s", strsignal(signum), signum, buffer);
+		else
+			ERROR("BACKTRACE:\n%s", buffer);
 		free(locations);
 	}
 }
 
+static void safe_dumpstack_cb(int signum, void *closure)
+{
+	int *args = closure;
+	if (signum)
+		ERROR("Can't provide backtrace: raised signal %s", strsignal(signum));
+	else
+		dumpstack(args[0], args[1]);
+}
+
+static void safe_dumpstack(int crop, int signum)
+{
+	int args[2] = { crop, signum };
+
+	in_safe_dumpstack = 1;
+	sig_monitor(0, safe_dumpstack_cb, args);
+	in_safe_dumpstack = 0;
+}
+
 /*
  * Creates a timer for the current thread
  *
@@ -129,7 +165,11 @@ static inline void timeout_delete()
 /* Handles signals that terminate the process */
 static void on_signal_terminate (int signum)
 {
-	ERROR("Terminating signal %d received: %s", signum, strsignal(signum));
+	if (!in_safe_dumpstack) {
+		ERROR("Terminating signal %d received: %s", signum, strsignal(signum));
+		if (signum == SIGABRT)
+			safe_dumpstack(3, signum);
+	}
 	exit(1);
 }
 
@@ -138,19 +178,19 @@ static void on_signal_error(int signum)
 {
 	sigset_t sigset;
 
+	if (in_safe_dumpstack)
+		longjmp(*error_handler, signum);
+
 	ERROR("ALERT! signal %d received: %s", signum, strsignal(signum));
 	if (error_handler == NULL && signum == SIG_FOR_TIMER)
 		return;
 
-	dumpstack(3);
+	safe_dumpstack(3, signum);
 
 	// unlock signal to allow a new signal to come
-	if (error_handler != NULL) {
-		sigemptyset(&sigset);
-		sigaddset(&sigset, signum);
-		sigprocmask(SIG_UNBLOCK, &sigset, 0);
+	if (error_handler != NULL)
 		longjmp(*error_handler, signum);
-	}
+
 	ERROR("Unmonitored signal %d received: %s", signum, strsignal(signum));
 	exit(2);
 }
@@ -159,9 +199,14 @@ static void on_signal_error(int signum)
 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 (signal(*signals, handler) == SIG_ERR) {
-			ERROR("failed to install signal handler for signal %s", strsignal(*signals));
+		if (sigaction(*signals, &sa, NULL) < 0) {
+			ERROR("failed to install signal handler for signal %s: %m", strsignal(*signals));
 			result = 0;
 		}
 		signals++;