[kernel] Add endpoint object and related syscalls

The endpoint object adds synchronous IPC. Also added the wait-type of
'object' to threads.

src/kernel/syscalls/endpoint.cpp

@@ -0,0 +1,99 @@
+#include "j6/errors.h"
+#include "j6/types.h"
+
+#include "log.h"
+#include "objects/endpoint.h"
+#include "objects/process.h"
+#include "scheduler.h"
+
+namespace syscalls {
+
+j6_status_t
+endpoint_create(j6_handle_t *handle)
+{
+	scheduler &s = scheduler::get();
+	TCB *tcb = s.current();
+	thread *parent = thread::from_tcb(tcb);
+	process &p = parent->parent();
+
+	endpoint *e = new endpoint;
+	*handle = p.add_handle(e);
+
+	return j6_status_ok;
+}
+
+j6_status_t
+endpoint_close(j6_handle_t handle)
+{
+	scheduler &s = scheduler::get();
+	TCB *tcb = s.current();
+	thread *parent = thread::from_tcb(tcb);
+	process &p = parent->parent();
+
+	kobject *o = p.lookup_handle(handle);
+	if (!o || o->get_type() != kobject::type::endpoint)
+		return j6_err_invalid_arg;
+
+	p.remove_handle(handle);
+	endpoint *e = static_cast<endpoint*>(o);
+	e->close();
+
+	return j6_status_ok;
+}
+
+j6_status_t
+endpoint_send(j6_handle_t handle, size_t len, void *data)
+{
+	scheduler &s = scheduler::get();
+	TCB *tcb = s.current();
+	thread *parent = thread::from_tcb(tcb);
+	process &p = parent->parent();
+
+	kobject *o = p.lookup_handle(handle);
+	if (!o || o->get_type() != kobject::type::endpoint)
+		return j6_err_invalid_arg;
+
+	endpoint *e = static_cast<endpoint*>(o);
+	j6_status_t status = e->send(len, data);
+	return status;
+}
+
+j6_status_t
+endpoint_receive(j6_handle_t handle, size_t *len, void *data)
+{
+	scheduler &s = scheduler::get();
+	TCB *tcb = s.current();
+	thread *parent = thread::from_tcb(tcb);
+	process &p = parent->parent();
+
+	kobject *o = p.lookup_handle(handle);
+	if (!o || o->get_type() != kobject::type::endpoint)
+		return j6_err_invalid_arg;
+
+	endpoint *e = static_cast<endpoint*>(o);
+	j6_status_t status = e->receive(len, data);
+	return status;
+}
+
+j6_status_t
+endpoint_sendrecv(j6_handle_t handle, size_t *len, void *data)
+{
+	scheduler &s = scheduler::get();
+	TCB *tcb = s.current();
+	thread *parent = thread::from_tcb(tcb);
+	process &p = parent->parent();
+
+	kobject *o = p.lookup_handle(handle);
+	if (!o || o->get_type() != kobject::type::endpoint)
+		return j6_err_invalid_arg;
+
+	endpoint *e = static_cast<endpoint*>(o);
+	j6_status_t status = e->send(*len, data);
+	if (status != j6_status_ok)
+		return status;
+
+	status = e->receive(len, data);
+	return status;
+}
+
+} // namespace syscalls