Android app restarts automatically after a crash

Question

My app is partly written in native app using C/C++. The problem is that whenever C/C++ part crashes for some reason the app dies and then restarts automatically. This causes

Answer 1

By default your application should not be automatically restarting. Generally one would have to register for this kind of thing, e.g. via the AlarmManager/keep alives.

Do you have a service as part of your application?

Answer 2

Try to handle crash signals (SIGSEGV etc.) and send kill to yourself in signal handler. This trick helps me.

Example:

#include <signal.h>
#include <unistd.h>


static void signal_handler(int signal, siginfo_t *info, void *reserved)
{
  kill(getpid(),SIGKILL);
}

extern "C" jint JNI_OnLoad(JavaVM* vm, void* /*reserved*/)
{
  struct sigaction handler;
  memset(&handler, 0, sizeof(handler));
  handler.sa_sigaction = signal_handler;
  handler.sa_flags = SA_SIGINFO;
  sigaction(SIGILL, &handler, NULL);
  sigaction(SIGABRT, &handler, NULL);
  sigaction(SIGBUS, &handler, NULL);
  sigaction(SIGFPE, &handler, NULL);
  sigaction(SIGSEGV, &handler, NULL);
  sigaction(SIGSTKFLT, &handler, NULL);
  return(JNI_VERSION_1_6);
}

UPDATE2

if you want to see crashlog in android logcat you should use this signal handler

static void signal_handler(int signal, siginfo_t *info, void *reserved)
{
 struct sockaddr_un addr;
 size_t namelen;
 socklen_t alen;
 int s, err;
 char name[] = "android:debuggerd";
 namelen  = strlen(name);

 // Test with length +1 for the *initial* '\0'.
 if ((namelen + 1) > sizeof(addr.sun_path)) {
    errno = EINVAL;
    return;
 }

 /* This is used for abstract socket namespace, we need
  * an initial '\0' at the start of the Unix socket path.
  *
  * Note: The path in this case is *not* supposed to be
  * '\0'-terminated. ("man 7 unix" for the gory details.)
  */
 memset (&addr, 0, sizeof addr);
 addr.sun_family = AF_LOCAL;
 addr.sun_path[0] = 0;
 memcpy(addr.sun_path + 1, name, namelen);

 alen = namelen + offsetof(struct sockaddr_un, sun_path) + 1;

 s = socket(AF_LOCAL, SOCK_STREAM, 0);
 if(s < 0) return;

 RETRY_ON_EINTR(err,connect(s, (struct sockaddr *) &addr, alen));
 if (err < 0) {
    close(s);
    s = -1;
 }

 pid_t tid = gettid();
 if(s>=0)
 {
   /* debugger knows our pid from the credentials on the
    * local socket but we need to tell it our tid.  It
    * is paranoid and will verify that we are giving a tid
    * that's actually in our process
    */
    int  ret;

    RETRY_ON_EINTR(ret, write(s, &tid, sizeof(unsigned)));
    if (ret == sizeof(unsigned)) {
        /* if the write failed, there is no point to read on
         * the file descriptor. */
        RETRY_ON_EINTR(ret, read(s, &tid, 1));
        //notify_gdb_of_libraries();
    }
    close(s);
 }

 wait(NULL);
 kill(getpid(),SIGKILL);
}

I took it from android source (can't insert link because android.git.kernel.org is down), but I am not sure that it will work in future Android releases