#define _GNU_SOURCE
#include <stdlib.h>
+#include <stdio.h>
#include <signal.h>
#include <string.h>
#include <setjmp.h>
#include <time.h>
#include <unistd.h>
#include <sys/syscall.h>
+#include <execinfo.h>
#include "sig-monitor.h"
#include "verbose.h"
+#define SIG_FOR_TIMER SIGVTALRM
+
/* 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;
static _Thread_local timer_t thread_timerid;
+/*
+ * Dumps the current stack
+ */
+static void dumpstack(int crop, int signum)
+{
+ int idx, count, rc;
+ void *addresses[100];
+ char **locations;
+ char buffer[8000];
+ size_t pos, length;
+
+ count = backtrace(addresses, sizeof addresses / sizeof *addresses);
+ 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 {
+ 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 + 3, signum };
+
+ in_safe_dumpstack = 1;
+ sig_monitor(0, safe_dumpstack_cb, args);
+ in_safe_dumpstack = 0;
+}
+
/*
* Creates a timer for the current thread
*
rc = 0;
else {
sevp.sigev_notify = SIGEV_THREAD_ID;
- sevp.sigev_signo = SIGALRM;
+ sevp.sigev_signo = SIG_FOR_TIMER;
sevp.sigev_value.sival_ptr = NULL;
#if defined(sigev_notify_thread_id)
sevp.sigev_notify_thread_id = (pid_t)syscall(SYS_gettid);
/* 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);
}
/* 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);
+
+ ERROR("ALERT! signal %d received: %s", signum, strsignal(signum));
+ if (error_handler == NULL && signum == SIG_FOR_TIMER)
+ return;
+
+ 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);
- }
- if (signum == SIGALRM)
- return;
+
ERROR("Unmonitored signal %d received: %s", signum, strsignal(signum));
exit(2);
}
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++;
int sig_monitor_init()
{
- static int sigerr[] = { SIGALRM, SIGSEGV, SIGFPE, 0 };
- static int sigterm[] = { SIGINT, SIGABRT, 0 };
+ static int sigerr[] = { SIG_FOR_TIMER, SIGSEGV, SIGFPE, SIGILL, SIGBUS, 0 };
+ static int sigterm[] = { SIGINT, SIGABRT, SIGTERM, 0 };
return (install(on_signal_error, sigerr) & install(on_signal_terminate, sigterm)) - 1;
}
}
void sig_monitor(int timeout, void (*function)(int sig, void*), void *arg)
-{
- sig_monitor3(timeout, (void (*)(int,void*,void*,void*))function, arg, NULL, NULL);
-}
-
-void sig_monitor2(int timeout, void (*function)(int sig, void*, void*), void *arg1, void *arg2)
-{
- sig_monitor3(timeout, (void (*)(int,void*,void*,void*))function, arg1, arg2, NULL);
-}
-
-void sig_monitor3(int timeout, void (*function)(int sig, void*, void*, void*), void *arg1, void *arg2, void *arg3)
{
volatile int signum, signum2;
sigjmp_buf jmpbuf, *older;
error_handler = &jmpbuf;
if (timeout)
timeout_arm(timeout);
- function(0, arg1, arg2, arg3);
+ function(0, arg);
} else {
signum2 = setjmp(jmpbuf);
if (signum2 == 0)
- function(signum, arg1, arg2, arg3);
+ function(signum, arg);
}
error_handler = older;
if (timeout)
}
-
-
-
Code Review / src / app-framework-binder.git / blobdiff