linux-user: proper exit code for uncaught signals

The proper exit code for dieing from an uncaught signal is -<signal>.
The kernel doesn't allow exit() or _exit() to pass a negative value.
To get the proper exit code we need to actually die from an uncaught signal.

A default signal handler is installed, we send ourself a signal
and we wait for it to arrive.

Patch originates from Scratchbox

Signed-off-by: Riku Voipio <riku.voipio@iki.fi>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7119 c046a42c-6fe2-441c-8c8c-71466251a162
This commit is contained in:
aurel32 2009-04-15 16:18:38 +00:00
parent 3b3f24add0
commit 603e4fd7b1

View File

@ -25,6 +25,7 @@
#include <unistd.h> #include <unistd.h>
#include <signal.h> #include <signal.h>
#include <errno.h> #include <errno.h>
#include <assert.h>
#include <sys/ucontext.h> #include <sys/ucontext.h>
#include "qemu.h" #include "qemu.h"
@ -352,22 +353,34 @@ static inline void free_sigqueue(CPUState *env, struct sigqueue *q)
static void QEMU_NORETURN force_sig(int sig) static void QEMU_NORETURN force_sig(int sig)
{ {
int host_sig; int host_sig;
struct sigaction act;
host_sig = target_to_host_signal(sig); host_sig = target_to_host_signal(sig);
fprintf(stderr, "qemu: uncaught target signal %d (%s) - exiting\n", fprintf(stderr, "qemu: uncaught target signal %d (%s) - exiting\n",
sig, strsignal(host_sig)); sig, strsignal(host_sig));
#if 1
gdb_signalled(thread_env, sig); gdb_signalled(thread_env, sig);
_exit(-host_sig);
#else /* The proper exit code for dieing from an uncaught signal is
{ * -<signal>. The kernel doesn't allow exit() or _exit() to pass
struct sigaction act; * a negative value. To get the proper exit code we need to
sigemptyset(&act.sa_mask); * actually die from an uncaught signal. Here the default signal
act.sa_flags = SA_SIGINFO; * handler is installed, we send ourself a signal and we wait for
act.sa_sigaction = SIG_DFL; * it to arrive. */
sigaction(SIGABRT, &act, NULL); sigfillset(&act.sa_mask);
abort(); act.sa_handler = SIG_DFL;
} sigaction(host_sig, &act, NULL);
#endif
/* For some reason raise(host_sig) doesn't send the signal when
* statically linked on x86-64. */
kill(getpid(), host_sig);
/* Make sure the signal isn't masked (just reuse the mask inside
of act) */
sigdelset(&act.sa_mask, host_sig);
sigsuspend(&act.sa_mask);
/* unreachable */
assert(0);
} }
/* queue a signal so that it will be send to the virtual CPU as soon /* queue a signal so that it will be send to the virtual CPU as soon