diff --git a/init/devices.h b/init/devices.h
index 8e9ab7d..d1e489b 100644
--- a/init/devices.h
+++ b/init/devices.h
@@ -17,10 +17,36 @@
 #ifndef _INIT_DEVICES_H
 #define _INIT_DEVICES_H
 
+#include <functional>
 #include <sys/stat.h>
 
-extern void handle_device_fd();
-extern void device_init(void);
+enum coldboot_action_t {
+    // coldboot continues without creating the device for the uevent
+    COLDBOOT_CONTINUE = 0,
+    // coldboot continues after creating the device for the uevent
+    COLDBOOT_CREATE,
+    // coldboot stops after creating the device for uevent but doesn't
+    // create the COLDBOOT_DONE file
+    COLDBOOT_STOP,
+    // same as COLDBOOT_STOP, but creates the COLDBOOT_DONE file
+    COLDBOOT_FINISH
+};
+
+struct uevent {
+    const char* action;
+    const char* path;
+    const char* subsystem;
+    const char* firmware;
+    const char* partition_name;
+    const char* device_name;
+    int partition_num;
+    int major;
+    int minor;
+};
+
+typedef std::function<coldboot_action_t(struct uevent* uevent)> coldboot_callback;
+extern coldboot_action_t handle_device_fd(coldboot_callback fn = nullptr);
+extern void device_init(const char* path = nullptr, coldboot_callback fn = nullptr);
 
 enum early_device_type { EARLY_BLOCK_DEV, EARLY_CHAR_DEV };