Object* Fiber::s_yield(STATE, Arguments& args) {
Fiber* fiber = state->vm()->fiber();
OnStack<1> os(state, fiber);
{
std::lock_guard<std::mutex> guard(state->vm()->thread()->fiber_mutex());
if(fiber->root_p()) {
Exception::raise_fiber_error(state, "can't yield from root fiber");
} else if(fiber->status() == eTransfer) {
Exception::raise_fiber_error(state, "can't yield from transferred fiber");
}
fiber->unpack_arguments(state, args);
fiber->status(eYielding);
}
// Being cooperative...
fiber->invoke_context()->fiber()->restart(state);
// Through the worm hole...
fiber->suspend_and_continue(state);
// We're back...
return fiber->return_value(state);
}
Fiber* Fiber::current(STATE) {
#ifdef RBX_FIBER_ENABLED
Fiber* fib = state->vm()->current_fiber.get();
// Lazily allocate a root fiber.
if(fib->nil_p()) {
fib = state->memory()->new_object<Fiber>(state, G(fiber));
fib->root(true);
fib->status(Fiber::eRunning);
fib->data(state->vm()->new_fiber_data(true, fib->stack_size()->to_native()));
fib->data()->set_call_frame(state->vm()->call_frame());
state->memory()->native_finalizer(state, fib,
(memory::FinalizerFunction)&Fiber::finalize);
state->vm()->current_fiber.set(fib);
state->vm()->root_fiber.set(fib);
}
return fib;
#else
Exception::raise_not_implemented_error(state, "Fibers not supported on this platform");
#endif
}
void Fiber::start_on_stack() {
#ifdef RBX_FIBER_ENABLED
VM* vm = VM::current();
State state_obj(vm), *state = &state_obj;
Fiber* fib = Fiber::current(state);
// Reset the current fiber again to reset the stack limits so
// we can properly detect stack overflows
vm->set_current_fiber(fib);
Array* result = nil<Array>();
Object* obj = fib->starter()->send(state, G(sym_call), fib->value(), cNil, false);
// GC has run! Don't use stack vars!
fib = Fiber::current(state);
fib->status(Fiber::eDead);
fib->dead(cTrue);
fib->set_call_frame(state, 0);
Fiber* dest = fib->prev();
// If this fiber has already been cleaned up, just ignore this
if(!dest->data()) return;
assert(!dest->nil_p());
// Box this up so it's in a standard format at the point
// of returning, so we can deal with it in the same way
// as *args from #yield, #resume, and #transfer
if(obj) {
result = Array::create(state, 1);
result->set(state, 0, obj);
} else {
if(state->vm()->thread_state()->raise_reason() == cException) {
dest->exception(state, state->vm()->thread_state()->current_exception());
}
}
vm->metrics().system.fibers_destroyed++;
dest->run(state);
dest->value(state, result);
dest->data()->switch_and_orphan(state, fib->data());
// TODO: CallFrame: return from this function
rubinius::bug("returning from Fiber::start_on_stack");
#else
rubinius::bug("Fibers not supported on this platform");
#endif
}
/* This creates the pseudo-Fiber for the Thread. This provides a uniform
* means of expressing things like Fiber.current.
*/
Fiber* Fiber::create(STATE, VM* vm) {
Fiber* fiber = state->memory()->new_object_pinned<Fiber>(state, G(fiber));
vm->set_fiber(fiber);
vm->set_running();
fiber->vm(vm);
fiber->pid(vm->thread()->pid());
fiber->stack_size(vm->thread()->stack_size());
fiber->thread_name(state, String::create(state, vm->name().c_str()));
fiber->fiber_id(Fixnum::from(0));
fiber->status(eRunning);
fiber->invoke_context(vm);
return fiber;
}