kernel: implement tty driver system

kernel/console.c

@@ -6,6 +6,20 @@
 static struct queue consoles;
 static spin_lock_t consoles_lock = SPIN_LOCK_INIT;
 
+static void unregister_boot_consoles(void)
+{
+	struct queue_entry *cur = queue_first(&consoles);
+	while (cur) {
+		struct queue_entry *next = cur->qe_next;
+		struct console *con = QUEUE_CONTAINER(struct console, c_list, cur);
+		if (con->c_flags & CON_BOOT) {
+			queue_delete(&consoles, cur);
+		}
+
+		cur = next;
+	}
+}
+
 kern_status_t console_register(struct console *con)
 {
 	unsigned long flags;
@@ -19,7 +33,13 @@ kern_status_t console_register(struct console *con)
 	}
 
 	queue_push_back(&consoles, &con->c_list);
+
+	if (!(con->c_flags & CON_BOOT)) {
+		unregister_boot_consoles();
+	}
+
 	spin_unlock_irqrestore(&consoles_lock, flags);
+
 	return KERN_OK;
 }