Filesystem/Win32: Recreate hardlinks on fs::pending_file

Utilities/File.cpp

@@ -2475,7 +2475,6 @@ bool fs::pending_file::commit(bool overwrite)
 	{
 		file.sync();
 	}
-
 #endif
 
 #ifdef _WIN32
@@ -2486,16 +2485,62 @@ bool fs::pending_file::commit(bool overwrite)
 		disp.DeleteFileW = false;
 		ensure(SetFileInformationByHandle(file.get_handle(), FileDispositionInfo, &disp, sizeof(disp)));
 	}
+
+	std::vector<std::wstring> hardlinkPaths;
+
+	const auto ws1 = to_wchar(m_path);
+
+	const HANDLE fileHandle = CreateFileW(ws1.get(), GENERIC_READ, FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, nullptr, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, nullptr);
+
+	while (fileHandle != INVALID_HANDLE_VALUE)
+	{
+		// Get file ID (used to check for hardlinks)
+		BY_HANDLE_FILE_INFORMATION fileInfo;
+
+		if (!GetFileInformationByHandle(fileHandle, &fileInfo) || fileInfo.nNumberOfLinks == 1)
+		{	
+			CloseHandle(fileHandle);
+			break;
+		}
+
+		// Buffer for holding link name
+		WCHAR linkNameBuffer[MAX_PATH];
+		HANDLE findHandle = FindFirstFileNameW(ws1.get(), 0, nullptr, linkNameBuffer);
+
+		if (findHandle != INVALID_HANDLE_VALUE)
+		{
+			const std::wstring_view ws1_sv = ws1.get();
+
+			do
+			{
+				if (linkNameBuffer != ws1_sv)
+				{
+					hardlinkPaths.push_back(linkNameBuffer);
+				}
+			}
+			while (FindNextFileNameW(findHandle, nullptr, linkNameBuffer));
+		}
+
+		// Clean up
+		FindClose(findHandle);
+		CloseHandle(fileHandle);
+		break;
+	}
 #endif
 
 	file.close();
 
 #ifdef _WIN32
-	const auto ws1 = to_wchar(m_path);
 	const auto ws2 = to_wchar(m_dest);
 
 	if (MoveFileExW(ws1.get(), ws2.get(), overwrite ? MOVEFILE_REPLACE_EXISTING | MOVEFILE_WRITE_THROUGH : MOVEFILE_WRITE_THROUGH))
 	{
+		for (auto&& path : hardlinkPaths)
+		{
+			// Recreate hard links
+			createHardLinkW(m_dest.c_str(), path.c_str());
+		}
+
 		// Disable the destructor
 		m_path.clear();
 		return true;