libei: add a few comments and extra checks

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>

src/libei-device.c

@@ -46,6 +46,7 @@ OBJECT_IMPLEMENT_PARENT(ei_device, ei);
 _public_ struct ei*
 ei_device_get_context(struct ei_device *device)
 {
+	assert(device);
 	return ei_device_parent(device);
 }
 
@@ -53,6 +54,8 @@ _public_
 struct ei_device *
 ei_device_new(struct ei *ei)
 {
+	/* device IDs are managed by the client, the server merely accepts
+	 * them and fails where they're being reused. */
 	static uint32_t deviceid = 0;
 	struct ei_device *device = ei_device_create(&ei->object);
 
@@ -67,6 +70,9 @@ _public_ bool
 ei_device_configure_capability(struct ei_device *device,
 			       enum ei_device_capability cap)
 {
+	if (device->state != EI_DEVICE_STATE_NEW)
+		return false;
+
 	switch (cap) {
 	case EI_DEVICE_CAP_POINTER:
 	case EI_DEVICE_CAP_POINTER_ABSOLUTE:
@@ -83,6 +89,7 @@ _public_ void
 ei_device_add(struct ei_device *device)
 {
 	ei_add_device(device);
+	device->state = EI_DEVICE_STATE_CONNECTING;
 }
 
 _public_ void

src/libei-private.h

@@ -55,6 +55,7 @@ struct ei {
 
 enum ei_device_state {
 	EI_DEVICE_STATE_NEW,
+	EI_DEVICE_STATE_CONNECTING,
 	EI_DEVICE_STATE_ACCEPTED,
 	EI_DEVICE_STATE_REMOVED,
 };

src/libei.c

@@ -82,7 +82,6 @@ message_free(struct message *msg)
 
 DEFINE_TRIVIAL_CLEANUP_FUNC(struct message*, message_free);
 
-
 static struct ei_event* ei_event_ref(struct ei_event *event);
 
 static void
@@ -700,6 +699,12 @@ ei_set_connection(struct ei *ei, int fd)
 _public_ void
 ei_configure_name(struct ei *ei, const char *name)
 {
+	if (ei->state != EI_STATE_NEW)
+		return;
+
+	if (strlen(name) > 1024)
+		return;
+
 	free(ei->name);
 	ei->name = xstrdup(name);
 }