Rewrite amux backend in Rust

.github/workflows/ci.yml

@@ -43,6 +43,8 @@ jobs:
     steps:
       - name: Checkout
         uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4
+        with:
+          submodules: recursive
 
       - name: Setup Go
         uses: actions/setup-go@d35c59abb061a4a6fb18e82ac0862c26744d6ab5 # v5.5.0

Sources/GhosttyTerminalView.swift

@@ -10,6 +10,14 @@ import Bonsplit
 import IOSurface
 import UniformTypeIdentifiers
 
+// Ghostty still exports these embedded-surface helpers, but the current
+// generated public header in this branch no longer declares them.
+@_silgen_name("ghostty_surface_clear_selection")
+private func cmuxGhosttySurfaceClearSelection(_ surface: ghostty_surface_t) -> Bool
+
+@_silgen_name("ghostty_surface_select_cursor_cell")
+private func cmuxGhosttySurfaceSelectCursorCell(_ surface: ghostty_surface_t) -> Bool
+
 #if os(macOS)
 func cmuxShouldUseTransparentBackgroundWindow() -> Bool {
     let defaults = UserDefaults.standard
@@ -1868,10 +1876,10 @@ class GhosttyApp {
 
     private func bellAudioPath() -> String? {
         guard let config else { return nil }
-        var value = ghostty_config_path_s()
+        var value: UnsafePointer<Int8>?
         let key = "bell-audio-path"
         guard ghostty_config_get(config, &value, key, UInt(key.lengthOfBytes(using: .utf8))),
-              let rawPath = value.path else {
+              let rawPath = value else {
             return nil
         }
         let path = String(cString: rawPath)
@@ -4679,7 +4687,7 @@ class GhosttyNSView: NSView, NSUserInterfaceValidations {
         guard surface != nil else { return false }
         setKeyboardCopyModeActive(!keyboardCopyModeActive)
         if !keyboardCopyModeActive, let surface {
-            _ = ghostty_surface_clear_selection(surface)
+            _ = cmuxGhosttySurfaceClearSelection(surface)
         }
         return true
     }
@@ -4690,13 +4698,13 @@ class GhosttyNSView: NSView, NSUserInterfaceValidations {
         keyboardCopyModeActive = active
         if active, let surface {
             keyboardCopyModeViewportRow = keyboardCopyModeSelectionAnchor(surface: surface)?.row
-            _ = ghostty_surface_clear_selection(surface)
+            _ = cmuxGhosttySurfaceClearSelection(surface)
             if keyboardCopyModeViewportRow == nil {
                 keyboardCopyModeViewportRow = keyboardCopyModeImeViewportRow(surface: surface)
             }
             // Create a 1-cell selection at the terminal cursor to serve as a
             // visible cursor indicator in copy mode.
-            _ = ghostty_surface_select_cursor_cell(surface)
+            _ = cmuxGhosttySurfaceSelectCursorCell(surface)
         } else {
             keyboardCopyModeViewportRow = nil
         }
@@ -4733,7 +4741,7 @@ class GhosttyNSView: NSView, NSUserInterfaceValidations {
     private func keyboardCopyModeSelectionAnchor(surface: ghostty_surface_t) -> (row: Int, y: Double)? {
         let size = ghostty_surface_size(surface)
         guard size.rows > 0, size.columns > 0 else { return nil }
-        guard ghostty_surface_select_cursor_cell(surface) else { return nil }
+        guard cmuxGhosttySurfaceSelectCursorCell(surface) else { return nil }
 
         var text = ghostty_text_s()
         guard ghostty_surface_read_selection(surface, &text) else { return nil }
@@ -4754,7 +4762,7 @@ class GhosttyNSView: NSView, NSUserInterfaceValidations {
         guard let anchor = keyboardCopyModeSelectionAnchor(surface: surface) else { return }
         keyboardCopyModeViewportRow = anchor.row
         // Preserve the visible cursor indicator.
-        _ = ghostty_surface_select_cursor_cell(surface)
+        _ = cmuxGhosttySurfaceSelectCursorCell(surface)
     }
 
     private func copyCurrentViewportLinesToClipboard(
@@ -4769,7 +4777,7 @@ class GhosttyNSView: NSView, NSUserInterfaceValidations {
         guard let anchor = keyboardCopyModeSelectionAnchor(surface: surface) else {
             return false
         }
-        _ = ghostty_surface_clear_selection(surface)
+        _ = cmuxGhosttySurfaceClearSelection(surface)
 
         var imeX: Double = 0
         var imeY: Double = 0
@@ -4825,18 +4833,18 @@ class GhosttyNSView: NSView, NSUserInterfaceValidations {
 
         switch action {
         case .exit:
-            _ = ghostty_surface_clear_selection(surface)
+            _ = cmuxGhosttySurfaceClearSelection(surface)
             setKeyboardCopyModeActive(false)
         case .startSelection:
             keyboardCopyModeVisualActive = true
         case .clearSelection:
             keyboardCopyModeVisualActive = false
-            _ = ghostty_surface_clear_selection(surface)
+            _ = cmuxGhosttySurfaceClearSelection(surface)
             // Re-create 1-cell cursor at terminal cursor position.
-            _ = ghostty_surface_select_cursor_cell(surface)
+            _ = cmuxGhosttySurfaceSelectCursorCell(surface)
         case .copyAndExit:
             _ = performBindingAction("copy_to_clipboard")
-            _ = ghostty_surface_clear_selection(surface)
+            _ = cmuxGhosttySurfaceClearSelection(surface)
             setKeyboardCopyModeActive(false)
         case .copyLineAndExit:
             let startRow = currentKeyboardCopyModeViewportRow(surface: surface)
@@ -4845,7 +4853,7 @@ class GhosttyNSView: NSView, NSUserInterfaceValidations {
                 startRow: startRow,
                 lineCount: count
             )
-            _ = ghostty_surface_clear_selection(surface)
+            _ = cmuxGhosttySurfaceClearSelection(surface)
             setKeyboardCopyModeActive(false)
         case let .scrollLines(delta):
             _ = performBindingAction("scroll_page_lines:\(delta * count)")

Sources/Workspace.swift

@@ -224,28 +224,6 @@ struct WorkspaceRemoteDaemonManifest: Decodable, Equatable {
     }
 }
 
-private struct BonsplitCompatibilityTabIDPayload: Codable {
-    let id: UUID
-}
-
-extension TabID {
-    var uuid: UUID {
-        if let id = Mirror(reflecting: self).children.first(where: { $0.label == "id" })?.value as? UUID {
-            return id
-        }
-
-        let decoder = JSONDecoder()
-        let encoder = JSONEncoder()
-
-        do {
-            let data = try encoder.encode(self)
-            return try decoder.decode(BonsplitCompatibilityTabIDPayload.self, from: data).id
-        } catch {
-            preconditionFailure("Failed to read Bonsplit TabID compatibility payload: \(error)")
-        }
-    }
-}
-
 extension Workspace {
     private static var compatibilityToggleZoomContextAction: TabContextAction? {
         TabContextAction(rawValue: "toggleZoom")

cmuxTests/TabManagerUnitTests.swift

@@ -989,7 +989,10 @@ final class BonsplitZoomCompatibilityTests: XCTestCase {
             receivedPaneId = incomingPaneId
         }
 
-        let paneId = controller.allPaneIds.first
+        guard let paneId = controller.allPaneIds.first else {
+            XCTFail("Expected a default Bonsplit pane")
+            return
+        }
         controller.onTabCloseRequest?(tabId, paneId)
 
         XCTAssertEqual(receivedTabId?.uuid, tabId.uuid)

daemon/remote/cmd/cmuxd-remote/ioctl_unix_darwin.go

@@ -0,0 +1,13 @@
+//go:build darwin
+
+package main
+
+import "syscall"
+
+func ioctlReadTermiosRequest() uintptr {
+	return syscall.TIOCGETA
+}
+
+func ioctlWriteTermiosRequest() uintptr {
+	return syscall.TIOCSETA
+}

daemon/remote/cmd/cmuxd-remote/ioctl_unix_linux.go

@@ -0,0 +1,13 @@
+//go:build linux
+
+package main
+
+import "syscall"
+
+func ioctlReadTermiosRequest() uintptr {
+	return syscall.TCGETS
+}
+
+func ioctlWriteTermiosRequest() uintptr {
+	return syscall.TCSETS
+}

daemon/remote/cmd/cmuxd-remote/main.go

@@ -54,6 +54,8 @@ func run(args []string, stdin io.Reader, stdout, stderr io.Writer) int {
 		fs := flag.NewFlagSet("serve", flag.ContinueOnError)
 		fs.SetOutput(stderr)
 		stdio := fs.Bool("stdio", false, "serve over stdin/stdout")
+		unixMode := fs.Bool("unix", false, "serve over a Unix socket")
+		socketPath := fs.String("socket", "", "Unix socket path")
 		tlsMode := fs.Bool("tls", false, "serve over TLS")
 		listenAddr := fs.String("listen", "", "TLS listen address")
 		serverID := fs.String("server-id", "", "server identifier for ticket verification")
@@ -63,8 +65,18 @@ func run(args []string, stdin io.Reader, stdout, stderr io.Writer) int {
 		if err := fs.Parse(args[1:]); err != nil {
 			return 2
 		}
-		if *stdio == *tlsMode {
-			_, _ = fmt.Fprintln(stderr, "serve requires exactly one of --stdio or --tls")
+		modeCount := 0
+		if *stdio {
+			modeCount++
+		}
+		if *unixMode {
+			modeCount++
+		}
+		if *tlsMode {
+			modeCount++
+		}
+		if modeCount != 1 {
+			_, _ = fmt.Fprintln(stderr, "serve requires exactly one of --stdio, --unix, or --tls")
 			return 2
 		}
 		if *stdio {
@@ -74,6 +86,13 @@ func run(args []string, stdin io.Reader, stdout, stderr io.Writer) int {
 			}
 			return 0
 		}
+		if *unixMode {
+			if err := runUnixServer(*socketPath); err != nil {
+				_, _ = fmt.Fprintf(stderr, "serve failed: %v\n", err)
+				return 1
+			}
+			return 0
+		}
 		if err := runTLSServer(direct.Config{
 			ServerID:     *serverID,
 			TicketSecret: []byte(*ticketSecret),
@@ -85,8 +104,12 @@ func run(args []string, stdin io.Reader, stdout, stderr io.Writer) int {
 			return 1
 		}
 		return 0
+	case "session":
+		return runSessionCLI(args[1:])
 	case "cli":
 		return runCLI(args[1:])
+	case "list", "ls", "attach", "status", "history", "kill", "new":
+		return runSessionCLI(args)
 	default:
 		usage(stderr)
 		return 2
@@ -97,7 +120,9 @@ func usage(w io.Writer) {
 	_, _ = fmt.Fprintln(w, "Usage:")
 	_, _ = fmt.Fprintln(w, "  cmuxd-remote version")
 	_, _ = fmt.Fprintln(w, "  cmuxd-remote serve --stdio")
+	_, _ = fmt.Fprintln(w, "  cmuxd-remote serve --unix --socket <path>")
 	_, _ = fmt.Fprintln(w, "  cmuxd-remote serve --tls --listen <addr> --server-id <id> --ticket-secret <secret> --cert-file <path> --key-file <path>")
+	_, _ = fmt.Fprintln(w, "  cmuxd-remote session <command> [args...]")
 	_, _ = fmt.Fprintln(w, "  cmuxd-remote cli <command> [args...]")
 }
 
@@ -107,6 +132,42 @@ func runStdioServer(stdin io.Reader, stdout io.Writer) error {
 	return rpc.NewServer(server.handleRequest).Serve(stdin, stdout)
 }
 
+func runUnixServer(socketPath string) error {
+	if socketPath == "" {
+		return errors.New("unix server requires --socket")
+	}
+	if err := os.MkdirAll(filepath.Dir(socketPath), 0o755); err != nil {
+		return err
+	}
+	_ = os.Remove(socketPath)
+
+	listener, err := net.Listen("unix", socketPath)
+	if err != nil {
+		return err
+	}
+	defer func() {
+		_ = listener.Close()
+		_ = os.Remove(socketPath)
+	}()
+
+	server := newDaemonServer()
+	defer server.closeAll()
+
+	for {
+		conn, err := listener.Accept()
+		if err != nil {
+			if errors.Is(err, net.ErrClosed) {
+				return nil
+			}
+			return err
+		}
+		go func(conn net.Conn) {
+			defer conn.Close()
+			_ = rpc.NewServer(server.handleRequest).Serve(conn, conn)
+		}(conn)
+	}
+}
+
 func runTLSServer(cfg direct.Config) error {
 	server := newDaemonServer()
 	defer server.closeAll()
@@ -181,6 +242,10 @@ func (s *daemonServer) handleRequest(req rpc.Request) rpc.Response {
 		return s.handleSessionDetach(req)
 	case "session.status":
 		return s.handleSessionStatus(req)
+	case "session.list":
+		return s.handleSessionList(req)
+	case "session.history":
+		return s.handleSessionHistory(req)
 	case "terminal.open":
 		return s.handleTerminalOpen(req)
 	case "terminal.read":
@@ -699,6 +764,52 @@ func (s *daemonServer) handleSessionStatus(req rpc.Request) rpc.Response {
 	}
 }
 
+func (s *daemonServer) handleSessionList(req rpc.Request) rpc.Response {
+	sessions := s.sessions.List()
+	result := make([]map[string]any, 0, len(sessions))
+	for _, status := range sessions {
+		result = append(result, map[string]any{
+			"session_id":       status.SessionID,
+			"attachment_count": len(status.Attachments),
+			"effective_cols":   status.EffectiveCols,
+			"effective_rows":   status.EffectiveRows,
+		})
+	}
+	return rpc.Response{
+		ID:     req.ID,
+		OK:     true,
+		Result: map[string]any{"sessions": result},
+	}
+}
+
+func (s *daemonServer) handleSessionHistory(req rpc.Request) rpc.Response {
+	sessionID, ok := getStringParam(req.Params, "session_id")
+	if !ok || sessionID == "" {
+		return rpc.Response{
+			ID: req.ID,
+			OK: false,
+			Error: &rpc.Error{
+				Code:    "invalid_params",
+				Message: "session.history requires session_id",
+			},
+		}
+	}
+
+	history, err := s.terminals.History(sessionID)
+	if err != nil {
+		return rpc.Response{
+			ID:    req.ID,
+			OK:    false,
+			Error: terminalError(err),
+		}
+	}
+	return rpc.Response{
+		ID:     req.ID,
+		OK:     true,
+		Result: map[string]any{"session_id": sessionID, "history": string(history)},
+	}
+}
+
 func (s *daemonServer) handleTerminalOpen(req rpc.Request) rpc.Response {
 	command, ok := getStringParam(req.Params, "command")
 	if !ok || command == "" {
@@ -735,7 +846,8 @@ func (s *daemonServer) handleTerminalOpen(req rpc.Request) rpc.Response {
 		}
 	}
 
-	sessionID, attachmentID := s.sessions.Open(cols, rows)
+	requestedSessionID, _ := getStringParam(req.Params, "session_id")
+	sessionID, attachmentID := s.sessions.Open(requestedSessionID, cols, rows)
 	status, err := s.sessions.Status(sessionID)
 	if err != nil {
 		return rpc.Response{ID: req.ID, OK: false, Error: sessionError(err)}

daemon/remote/cmd/cmuxd-remote/main_test.go

@@ -1,8 +1,8 @@
 package main
 
 import (
-	"encoding/base64"
 	"bufio"
+	"encoding/base64"
 	"encoding/json"
 	"fmt"
 	"io"
@@ -131,8 +131,8 @@ func TestServeStdioSupportsTerminalOpenReadAndWrite(t *testing.T) {
 		t.Fatalf("terminal.read echo result missing: %+v", readEcho)
 	}
 	echoChunk := decodeBase64Field(t, echoResult, "data")
-	if string(echoChunk) != "hello\r\n" {
-		t.Fatalf("echo chunk = %q, want %q", string(echoChunk), "hello\r\n")
+	if string(echoChunk) != "hello\n" {
+		t.Fatalf("echo chunk = %q, want %q", string(echoChunk), "hello\n")
 	}
 
 	_ = stdinW.Close()