fix: update xauth on reboot/change

TODO.md

@@ -0,0 +1,13 @@
+# Ideas, Features, Roadmap
+
+## Known Bugs
+
+- the xauthority device changes when x or wayland is restarted. `igloo enter` should validate the existence of the xauthority device on each enter, replacing it if necessary
+
+## Ideas
+
+- On a host with no VS Code install, we'll be running code inside each igloo container. It'd be nice to share settings between them. Can't really symlink the ~/.vscode dir from the host since it won't exist. Explore having a Shared State sort of thing where directories like that live in ~/.config/igloo/shared_state and are linked in (by default? configurable?). Implement: `[shared_state]` section in config file that stores listed directories in ~/.config/igloo/shared_state and symlinks listed directories into the container, allowing all igloo instances to share these directories. This feature could be used for one-off script storage too.
+
+- copy the igloo binary into the container, and add one or more commands intended to run inside the container. Perhaps showing, editing `shared_state` contents? definitely `igloo status` should work inside the container and show that it knows it's inside.
+
+- modify PS1 in the container to add `[igloo]` prefix, change color of prompt, something visual as an indicator? Or... simply add a tip in the readme showing how to do this.

cmd/enter.go

@@ -117,6 +117,11 @@ func runEnter() error {
 		}
 	}
 
+	// Update Xauthority mount if necessary (file path can change on Wayland)
+	if err := client.UpdateXauthority(cfg.Container.Name); err != nil {
+		fmt.Println(styles.Warning(fmt.Sprintf("Could not update Xauthority: %v", err)))
+	}
+
 	// Get user info
 	username := os.Getenv("USER")
 	cwd, err := os.Getwd()

internal/incus/client.go

@@ -154,6 +154,85 @@ func (c *Client) AddGPUDevice(name string) error {
 	return cmd.Run()
 }
 
+// RemoveDevice removes a device from an instance
+func (c *Client) RemoveDevice(name, deviceName string) error {
+	cmd := exec.Command("incus", "config", "device", "remove", name, deviceName)
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	return cmd.Run()
+}
+
+// DeviceExists checks if a device exists on an instance
+func (c *Client) DeviceExists(name, deviceName string) (bool, error) {
+	cmd := exec.Command("incus", "config", "device", "show", name)
+	output, err := cmd.Output()
+	if err != nil {
+		return false, fmt.Errorf("failed to list devices: %w", err)
+	}
+
+	// Simple check if device name appears in output
+	return strings.Contains(string(output), deviceName+":"), nil
+}
+
+// GetDeviceSource gets the source path of a disk device
+func (c *Client) GetDeviceSource(name, deviceName string) (string, error) {
+	cmd := exec.Command("incus", "config", "device", "get", name, deviceName, "source")
+	output, err := cmd.Output()
+	if err != nil {
+		return "", fmt.Errorf("failed to get device source: %w", err)
+	}
+	return strings.TrimSpace(string(output)), nil
+}
+
+// UpdateXauthority updates the xauthority device mount if the source file has changed
+// This is necessary because XWayland can create new Xauthority files when restarted
+func (c *Client) UpdateXauthority(name string) error {
+	// Get current Xauthority file from environment
+	xauthFile := os.Getenv("XAUTHORITY")
+	if xauthFile == "" {
+		xauthFile = os.Getenv("HOME") + "/.Xauthority"
+	}
+
+	// Check if the file exists
+	if _, err := os.Stat(xauthFile); os.IsNotExist(err) {
+		// No xauthority file available, nothing to update
+		return nil
+	}
+
+	// Check if xauthority device exists
+	deviceExists, err := c.DeviceExists(name, "xauthority")
+	if err != nil {
+		return fmt.Errorf("failed to check xauthority device: %w", err)
+	}
+
+	username := os.Getenv("USER")
+	xauthPath := fmt.Sprintf("/home/%s/.Xauthority", username)
+
+	if !deviceExists {
+		// Device doesn't exist, add it
+		return c.AddDiskDevice(name, "xauthority", xauthFile, xauthPath)
+	}
+
+	// Device exists, check if source has changed
+	currentSource, err := c.GetDeviceSource(name, "xauthority")
+	if err != nil {
+		return fmt.Errorf("failed to get current xauthority source: %w", err)
+	}
+
+	if currentSource != xauthFile {
+		// Source has changed, remove and re-add the device
+		if err := c.RemoveDevice(name, "xauthority"); err != nil {
+			return fmt.Errorf("failed to remove old xauthority device: %w", err)
+		}
+
+		if err := c.AddDiskDevice(name, "xauthority", xauthFile, xauthPath); err != nil {
+			return fmt.Errorf("failed to add new xauthority device: %w", err)
+		}
+	}
+
+	return nil
+}
+
 // SetConfig sets a configuration option on an instance
 func (c *Client) SetConfig(name, key, value string) error {
 	cmd := exec.Command("incus", "config", "set", name, key+"="+value)

internal/incus/client_test.go

@@ -0,0 +1,129 @@
+package incus
+
+import (
+	"os"
+	"strings"
+	"testing"
+)
+
+// TestUpdateXauthority_NoFile tests UpdateXauthority when no xauthority file exists
+func TestUpdateXauthority_NoFile(t *testing.T) {
+	// Save current env vars
+	oldXauth := os.Getenv("XAUTHORITY")
+	oldHome := os.Getenv("HOME")
+	defer func() {
+		if oldXauth != "" {
+			_ = os.Setenv("XAUTHORITY", oldXauth)
+		} else {
+			_ = os.Unsetenv("XAUTHORITY")
+		}
+		_ = os.Setenv("HOME", oldHome)
+	}()
+
+	// Set env to point to non-existent file
+	tmpDir := t.TempDir()
+	_ = os.Setenv("HOME", tmpDir)
+	_ = os.Unsetenv("XAUTHORITY")
+
+	client := NewClient()
+
+	// This should not error when file doesn't exist - it just returns nil
+	err := client.UpdateXauthority("test-container")
+	if err != nil {
+		t.Errorf("UpdateXauthority() should not error when file doesn't exist, got: %v", err)
+	}
+}
+
+// TestUpdateXauthority_WithFile tests UpdateXauthority when xauthority file exists
+// Note: This test can't fully test the incus commands without a running incus instance,
+// but it verifies the file detection logic works
+func TestUpdateXauthority_WithFile(t *testing.T) {
+	// Save current env vars
+	oldXauth := os.Getenv("XAUTHORITY")
+	oldHome := os.Getenv("HOME")
+	oldUser := os.Getenv("USER")
+	defer func() {
+		if oldXauth != "" {
+			_ = os.Setenv("XAUTHORITY", oldXauth)
+		} else {
+			_ = os.Unsetenv("XAUTHORITY")
+		}
+		_ = os.Setenv("HOME", oldHome)
+		_ = os.Setenv("USER", oldUser)
+	}()
+
+	// Create a temporary xauthority file
+	tmpDir := t.TempDir()
+	xauthFile := tmpDir + "/.Xauthority"
+	if err := os.WriteFile(xauthFile, []byte("fake xauth data"), 0600); err != nil {
+		t.Fatalf("Failed to create test xauthority file: %v", err)
+	}
+
+	_ = os.Setenv("HOME", tmpDir)
+	_ = os.Setenv("USER", "testuser")
+	_ = os.Unsetenv("XAUTHORITY")
+
+	client := NewClient()
+
+	// This will attempt to call incus commands which will fail without incus installed
+	// but we can verify it at least tries to process the file
+	err := client.UpdateXauthority("test-container")
+
+	// We expect an error because incus isn't available in test environment,
+	// but we're verifying the logic path is taken when the file exists
+	// The function should have attempted to check device existence
+	if err == nil {
+		// If no error, then either incus is available (unlikely in CI)
+		// or the logic correctly handled the case
+		t.Log("UpdateXauthority succeeded (incus may be available)")
+	} else {
+		// Expected case: incus command failed
+		errMsg := err.Error()
+		if !strings.Contains(errMsg, "incus") && !strings.Contains(errMsg, "device") &&
+			!strings.Contains(errMsg, "executable file not found") && !strings.Contains(errMsg, "command not found") {
+			t.Errorf("Expected incus-related error, got: %v", err)
+		}
+	}
+}
+
+// TestUpdateXauthority_CustomPath tests UpdateXauthority with XAUTHORITY env var set
+func TestUpdateXauthority_CustomPath(t *testing.T) {
+	// Save current env vars
+	oldXauth := os.Getenv("XAUTHORITY")
+	oldUser := os.Getenv("USER")
+	defer func() {
+		if oldXauth != "" {
+			_ = os.Setenv("XAUTHORITY", oldXauth)
+		} else {
+			_ = os.Unsetenv("XAUTHORITY")
+		}
+		_ = os.Setenv("USER", oldUser)
+	}()
+
+	// Create a temporary xauthority file with custom path
+	tmpDir := t.TempDir()
+	xauthFile := tmpDir + "/.mutter-Xwaylandauth.ABC123"
+	if err := os.WriteFile(xauthFile, []byte("fake xauth data"), 0600); err != nil {
+		t.Fatalf("Failed to create test xauthority file: %v", err)
+	}
+
+	_ = os.Setenv("XAUTHORITY", xauthFile)
+	_ = os.Setenv("USER", "testuser")
+
+	client := NewClient()
+
+	// This will attempt to call incus commands which will fail without incus installed
+	err := client.UpdateXauthority("test-container")
+
+	// We expect an error because incus isn't available in test environment
+	if err == nil {
+		t.Log("UpdateXauthority succeeded (incus may be available)")
+	} else {
+		// Expected case: incus command failed
+		errMsg := err.Error()
+		if !strings.Contains(errMsg, "incus") && !strings.Contains(errMsg, "device") &&
+			!strings.Contains(errMsg, "executable file not found") && !strings.Contains(errMsg, "command not found") {
+			t.Errorf("Expected incus-related error, got: %v", err)
+		}
+	}
+}