Move the code from lib.rs to separate files

src/common.rs

@@ -0,0 +1,26 @@
+// Copyright 2023, Igor Shaula
+// Licensed under the MIT License <LICENSE or
+// http://opensource.org/licenses/MIT>. This file
+// may not be copied, modified, or distributed
+// except according to those terms.
+#![macro_use]
+use std::ffi::OsStr;
+use std::os::windows::ffi::OsStrExt;
+use std::slice;
+
+macro_rules! werr {
+    ($e:expr) => {
+        Err(io::Error::from_raw_os_error($e as i32))
+    };
+}
+
+pub(crate) fn to_utf16<P: AsRef<OsStr>>(s: P) -> Vec<u16> {
+    s.as_ref()
+        .encode_wide()
+        .chain(Some(0).into_iter())
+        .collect()
+}
+
+pub(crate) fn v16_to_v8(v: &[u16]) -> Vec<u8> {
+    unsafe { slice::from_raw_parts(v.as_ptr() as *const u8, v.len() * 2).to_vec() }
+}

src/decoder/mod.rs

@@ -4,7 +4,7 @@
 // may not be copied, modified, or distributed
 // except according to those terms.
 use crate::enums::*;
-use crate::RegKey;
+use crate::reg_key::RegKey;
 use std::error::Error;
 use std::fmt;
 use std::io;

src/encoder/mod.rs

@@ -5,8 +5,8 @@
 // except according to those terms.
 use self::EncoderState::*;
 use crate::enums::*;
+use crate::reg_key::RegKey;
 use crate::transaction::Transaction;
-use crate::RegKey;
 use std::error::Error;
 use std::fmt;
 use std::io;