syscall: task: implement thread_self

syscall/dispatch.c

@@ -10,6 +10,7 @@ static const virt_addr_t syscall_table[] = {
 	SYSCALL_TABLE_ENTRY(TASK_CREATE, task_create),
 	SYSCALL_TABLE_ENTRY(TASK_CREATE_THREAD, task_create_thread),
 	SYSCALL_TABLE_ENTRY(TASK_GET_ADDRESS_SPACE, task_get_address_space),
+	SYSCALL_TABLE_ENTRY(THREAD_SELF, thread_self),
 	SYSCALL_TABLE_ENTRY(THREAD_START, thread_start),
 	SYSCALL_TABLE_ENTRY(THREAD_EXIT, thread_exit),
 	SYSCALL_TABLE_ENTRY(THREAD_CONFIG_GET, thread_config_get),

syscall/task.c

@@ -262,6 +262,37 @@ kern_status_t sys_task_get_address_space(
 	return KERN_OK;
 }
 
+kern_status_t sys_thread_self(kern_handle_t *out)
+{
+	struct task *self = current_task();
+	if (!validate_access_w(self, out, sizeof *out)) {
+		return KERN_MEMORY_FAULT;
+	}
+
+	struct thread *self_thread = current_thread();
+
+	unsigned long flags;
+	task_lock_irqsave(self, &flags);
+
+	struct handle *handle_slot = NULL;
+	kern_handle_t handle;
+	kern_status_t status = handle_table_alloc_handle(
+		self->t_handles,
+		&handle_slot,
+		&handle);
+	task_unlock_irqrestore(self, flags);
+
+	if (status != KERN_OK) {
+		return status;
+	}
+
+	object_add_handle(&self_thread->tr_base);
+	handle_slot->h_object = &self_thread->tr_base;
+
+	*out = handle;
+	return KERN_OK;
+}
+
 kern_status_t sys_thread_start(kern_handle_t thread_handle)
 {
 	unsigned long flags;