switch to "auto method() -> return_type" convention in device object

src/hvpp/hvpp/lib/device.h

@@ -12,44 +12,40 @@
 class device
 {
   public:
-             device() noexcept = default;
-    virtual ~device() noexcept { destroy(); }
-
-    virtual const char* name() const noexcept = 0;
+    device() noexcept = default;
+    device(const device& other) noexcept = delete;
+    device(device&& other) noexcept = delete;
+    device& operator=(const device& other) noexcept = delete;
+    device& operator=(device&& other) noexcept = delete;
+    virtual ~device() noexcept
+    { destroy(); }
 
     auto create() noexcept -> error_code_t;
     void destroy() noexcept;
 
-    //
-    // Dispatch methods.
-    //
+    virtual auto name() const noexcept -> const char * = 0;
 
     //
-    // A function declared with a return type that uses a placeholder
-    // type shall not be virtual ([class.virtual]).
-    // (ref: C++ standard, [dcl.spec.auto])
-    //
-    // TL;DR:
-    //   We can't use "virtual auto on_create() -> error_code_t" :(
+    // Dispatch methods.
     //
 
-    virtual error_code_t on_create() noexcept
+    virtual auto on_create() noexcept -> error_code_t
     { return {}; }
 
-    virtual error_code_t on_close() noexcept
+    virtual auto on_close() noexcept -> error_code_t
     { return {}; }
 
-    virtual error_code_t on_read(void* buffer, size_t buffer_size, size_t& bytes_read) noexcept
+    virtual auto on_read(void* buffer, size_t buffer_size, size_t& bytes_read) noexcept -> error_code_t
     { (void)(buffer); (void)(buffer_size); (void)(bytes_read); return {}; }
 
-    virtual error_code_t on_write(void* buffer, size_t buffer_size, size_t& bytes_written) noexcept
+    virtual auto on_write(void* buffer, size_t buffer_size, size_t& bytes_written) noexcept -> error_code_t
     { (void)(buffer); (void)(buffer_size); (void)(bytes_written); return {}; }
 
-    virtual error_code_t on_ioctl(void* buffer, size_t buffer_size, uint32_t code) noexcept
+    virtual auto on_ioctl(void* buffer, size_t buffer_size, uint32_t code) noexcept -> error_code_t
     { (void)(buffer); (void)(buffer_size); (void)(code); return {}; }
 
-    static error_code_t copy_from_user(void* buffer_to, const void* buffer_from, size_t length) noexcept;
-    static error_code_t copy_to_user(void* buffer_to, const void* buffer_from, size_t length) noexcept;
+    static auto copy_from_user(void* buffer_to, const void* buffer_from, size_t length) noexcept -> error_code_t;
+    static auto copy_to_user(void* buffer_to, const void* buffer_from, size_t length) noexcept -> error_code_t;
 
   private:
     void* impl_;

src/hvpp/hvpp/lib/win32/device.cpp

@@ -166,7 +166,7 @@ void device::destroy() noexcept
   impl_ = nullptr;
 }
 
-error_code_t device::copy_from_user(void* buffer_to, const void* buffer_from, size_t length) noexcept
+auto device::copy_from_user(void* buffer_to, const void* buffer_from, size_t length) noexcept -> error_code_t
 {
   if (!length)
   {
@@ -200,7 +200,7 @@ error_code_t device::copy_from_user(void* buffer_to, const void* buffer_from, si
   return {};
 }
 
-error_code_t device::copy_to_user(void* buffer_to, const void* buffer_from, size_t length) noexcept
+auto device::copy_to_user(void* buffer_to, const void* buffer_from, size_t length) noexcept -> error_code_t
 {
   if (!length)
   {