Fix web terminal issues: improve xterm.js configuration, fix PTY setup, and...

Fix web terminal issues: improve xterm.js configuration, fix PTY setup, and resolve output alignment

- Enhanced xterm.js terminal configuration with proper theme, cursor, and font settings
- Fixed PTY setup in wssshd.py for better subprocess connection
- Improved terminal output formatting and line ending handling
- Resolved terminal connection and data flow issues
- Added proper terminal size configuration (80x24)
- Simplified input handling for better SSH compatibility

templates/terminal.html

@@ -45,10 +45,27 @@ function connect() {
         return;
     }
 
-    // Initialize xterm
+    // Initialize xterm with proper configuration
     if (!term) {
-        term = new Terminal();
+        term = new Terminal({
+            cursorBlink: true,
+            cursorStyle: 'block',
+            fontSize: 14,
+            fontFamily: 'Monaco, Menlo, "Ubuntu Mono", monospace',
+            theme: {
+                background: '#1e1e1e',
+                foreground: '#f8f8f2',
+                cursor: '#f8f8f2',
+                cursorAccent: '#1e1e1e',
+                selection: 'rgba(248, 248, 242, 0.3)'
+            },
+            allowTransparency: true,
+            scrollback: 1000,
+            tabStopWidth: 4,
+            convertEol: true
+        });
         term.open(document.getElementById('terminal'));
+        term.focus();
     }
 
     term.write('Connecting to ' + username + '@{{ client_id }}...\r\n');
@@ -74,8 +91,8 @@ function connect() {
                 term.write('Launching: ' + data.command + '\r\n');
             }
             term.write('Connected successfully!\r\n$ ');
-            // Start polling for data
-            pollInterval = setInterval(pollData, 500);
+            // Start polling for data with shorter interval for better responsiveness
+            pollInterval = setInterval(pollData, 100);
         } else {
             term.write('Error: ' + data.error + '\r\n');
             disconnect();
@@ -86,9 +103,11 @@ function connect() {
         disconnect();
     });
 
-    // Handle input
+    // Handle input - let SSH server handle echoing
     term.onData(data => {
         if (!connected || !requestId) return;
+
+        // Send data to server
         fetch('/terminal/{{ client_id }}/data', {
             method: 'POST',
             headers: {
@@ -132,8 +151,12 @@ function pollData() {
     .then(response => response.text())
     .then(data => {
         if (data) {
-            term.write(data);
+            // Ensure proper line ending handling
+            term.write(data.replace(/\n/g, '\r\n'));
         }
+    })
+    .catch(error => {
+        console.error('Polling error:', error);
     });
 }
 

wssshd.py

@@ -31,6 +31,9 @@ import uuid
 import subprocess
 import pty
 import select
+import fcntl
+import termios
+import stat
 from flask import Flask, render_template, request, redirect, url_for, flash, jsonify, send_from_directory
 from flask_login import LoginManager, UserMixin, login_user, login_required, logout_user, current_user
 from flask_sqlalchemy import SQLAlchemy
@@ -69,6 +72,72 @@ class User(UserMixin, db.Model):
 def load_user(user_id):
     return db.session.get(User, int(user_id))
 
+def openpty_with_fallback():
+    """Open a PTY with fallback to different device paths for systems where /dev/pty doesn't exist"""
+    # First try the standard pty.openpty()
+    try:
+        master, slave = pty.openpty()
+        return master, slave
+    except OSError as e:
+        if debug:
+            print(f"[DEBUG] Standard pty.openpty() failed: {e}, trying fallback methods")
+
+    # Fallback: try to open /dev/ptmx directly
+    ptmx_paths = ['/dev/ptmx', '/dev/pts/ptmx']
+    for ptmx_path in ptmx_paths:
+        try:
+            if os.path.exists(ptmx_path):
+                # Open master PTY
+                master = os.open(ptmx_path, os.O_RDWR | os.O_NOCTTY)
+                if master < 0:
+                    continue
+
+                # Get slave PTY name
+                slave_name = os.ttyname(master)
+                if not slave_name:
+                    os.close(master)
+                    continue
+
+                # Open slave PTY
+                slave = os.open(slave_name, os.O_RDWR | os.O_NOCTTY)
+                if slave < 0:
+                    os.close(master)
+                    continue
+
+                if debug:
+                    print(f"[DEBUG] Successfully opened PTY using {ptmx_path}: master={master}, slave={slave}")
+                return master, slave
+        except (OSError, AttributeError) as e:
+            if debug:
+                print(f"[DEBUG] Failed to open PTY using {ptmx_path}: {e}")
+            continue
+
+    # Last resort: try to create PTY devices manually
+    try:
+        # Try to find an available PTY number
+        for i in range(256):  # Try PTY numbers 0-255
+            pty_name = f"/dev/pts/{i}"
+            try:
+                if os.path.exists(pty_name):
+                    continue
+                # Try to create the PTY device
+                master = os.open('/dev/ptmx', os.O_RDWR | os.O_NOCTTY)
+                slave_name = os.ttyname(master)
+                if slave_name and os.path.exists(slave_name):
+                    slave = os.open(slave_name, os.O_RDWR | os.O_NOCTTY)
+                    if debug:
+                        print(f"[DEBUG] Created PTY manually: master={master}, slave={slave}")
+                    return master, slave
+                os.close(master)
+            except (OSError, AttributeError):
+                continue
+    except Exception as e:
+        if debug:
+            print(f"[DEBUG] Manual PTY creation failed: {e}")
+
+    # If all methods fail, raise the original exception
+    raise OSError("Failed to open PTY: no available PTY devices found")
+
 # Create database and default admin user
 with app.app_context():
     db.create_all()
@@ -186,15 +255,41 @@ def connect_terminal(client_id):
     username = request.form.get('username', 'root')
     request_id = str(uuid.uuid4())
     command = ['wsssh', '-p', str(args.port), f'{username}@{client_id}.{args.domain}']
-    # Spawn wsssh process with pty
-    master, slave = pty.openpty()
+    # Spawn wsssh process with pty using fallback method
+    master, slave = openpty_with_fallback()
+    slave_name = os.ttyname(slave)
+
+    def set_controlling_terminal():
+        os.setsid()
+
+        # Set the controlling terminal
+        try:
+            fcntl.ioctl(slave, termios.TIOCSCTTY, 0)
+        except (OSError, AttributeError):
+            pass  # Some systems don't support TIOCSCTTY
+
+        # Set terminal size to match xterm.js dimensions
+        import struct
+        winsize = struct.pack('HHHH', 24, 80, 0, 0)
+        try:
+            fcntl.ioctl(0, termios.TIOCSWINSZ, winsize)
+        except (OSError, AttributeError):
+            pass
+
+        # Set raw mode - let SSH client handle terminal behavior
+        import tty
+        try:
+            tty.setraw(0)
+        except (OSError, AttributeError):
+            pass
+
     proc = subprocess.Popen(
         command,
         stdin=slave,
         stdout=slave,
         stderr=slave,
-        preexec_fn=os.setsid,
-        env=dict(os.environ, TERM='xterm')
+        preexec_fn=set_controlling_terminal,
+        env=dict(os.environ, TERM='xterm', COLUMNS='80', LINES='24')
     )
     os.close(slave)