dev: implement writing/reading input events to/from input devices

dev/core.c

@@ -79,6 +79,26 @@ struct device *device_alloc(void)
 	return DEVICE_CAST(dev_object);
 }
 
+kern_status_t device_read(struct device *dev, void *buf, size_t size, size_t *bytes_read)
+{
+	switch (dev->dev_type) {
+	case DEV_TYPE_INPUT:
+		return input_device_read(dev, buf, size, bytes_read);
+	default:
+		return KERN_UNSUPPORTED;
+	}
+}
+
+kern_status_t device_write(struct device *dev, const void *buf, size_t size, size_t *bytes_written)
+{
+	return KERN_UNSUPPORTED;
+}
+
+struct device *cast_to_device(struct object *obj)
+{
+	return DEVICE_CAST(obj);
+}
+
 static kern_status_t device_object_destroy(struct object *obj)
 {
 	return KERN_OK;

dev/input.c

@@ -1,4 +1,5 @@
 #include <socks/device.h>
+#include <socks/input.h>
 
 struct input_device *input_device_create(void)
 {
@@ -8,5 +9,43 @@ struct input_device *input_device_create(void)
 	}
 
 	dev->dev_type = DEV_TYPE_INPUT;
+
+	struct input_device *input_dev = INPUT_DEVICE(dev);
+	if (ringbuffer_init(&input_dev->i_events, INPUT_DEVICE_EVENT_QUEUE_SIZE * sizeof(struct input_event)) != KERN_OK) {
+		/* TODO destroy device */
+		return NULL;
+	}
+
 	return INPUT_DEVICE(dev);
 }
+
+kern_status_t input_device_report_event(struct input_device *dev, const struct input_event *ev, bool noblock)
+{
+	struct ringbuffer *event_queue = &dev->i_events;
+	enum ringbuffer_flags flags = RB_NORMAL;
+	if (noblock) {
+		flags = RB_NOBLOCK;
+	}
+
+	size_t r = ringbuffer_write(event_queue, sizeof *ev, ev, flags);
+
+	return r == sizeof *ev ? KERN_OK : KERN_WOULD_BLOCK;
+}
+
+kern_status_t input_device_read(struct device *dev, void *buf, size_t size, size_t *bytes_read)
+{
+	if (dev->dev_type != DEV_TYPE_INPUT || (size % sizeof (struct input_event)) != 0) {
+		return KERN_INVALID_ARGUMENT;
+	}
+
+	struct input_device *input_dev = INPUT_DEVICE(dev);
+	struct ringbuffer *event_queue = &input_dev->i_events;
+
+	size_t r = ringbuffer_read(event_queue, size, buf, RB_NORMAL);
+
+	if (bytes_read) {
+		*bytes_read = r;
+	}
+
+	return KERN_OK;
+}