lib, vm: reimplement exit() as exception type

Instead of invoking exit(3) from uc_exit(), use a new EXCEPTION_EXIT
exception type to instruct the VM to shutdown cleanly.

This is required to not terminate the host program in case libucode
is embedded and loaded scripts invoke the exit() function.

Signed-off-by: Jo-Philipp Wich <jo@mein.io>

1 files changed, 5 insertions, 2 deletions

diff --git a/lib.c b/lib.c
index 750acfb..cd0f582 100644
--- a/lib.c
+++ b/lib.c
@@ -502,12 +502,15 @@ uc_exists(uc_vm *vm, size_t nargs)
 	return ucv_boolean_new(found);
 }
 
-__attribute__((noreturn)) static uc_value_t *
+static uc_value_t *
 uc_exit(uc_vm *vm, size_t nargs)
 {
 	int64_t n = uc_cast_int64(uc_get_arg(0));
 
-	exit(n);
+	vm->arg.s32 = (int32_t)n;
+	uc_vm_raise_exception(vm, EXCEPTION_EXIT, "Terminated");
+
+	return NULL;
 }
 
 static uc_value_t *