From 32732823475676a1b28aa0fb6329f6fb45a3e125 Mon Sep 17 00:00:00 2001
From: Johannes Altmanninger <aclopte@gmail.com>
Date: Sat, 26 Jul 2025 09:39:09 +0200
Subject: [PATCH] Parse DCS and OSC commands

As reported in
https://github.com/fish-shell/fish-shell/issues/11609#issuecomment-3114092441,
a Proxmox Terminal (https://git.proxmox.com/git/novnc-pve) fails to
parse OSC commands such as:

	bash$ printf '\x1b]133;A;click_events=1\x07'

Judging by the Git history of the novnc-pve repo, it looks like they
use websockify-js.  They no longer vendor VT100.js, so hopefully
we only need to fix this here. Untested (happy to do that; not yet
sure how).
---
 include/VT100.js | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/include/VT100.js b/include/VT100.js
index 6a325e1..f1b5708 100644
--- a/include/VT100.js
+++ b/include/VT100.js
@@ -697,6 +697,11 @@ VT100.prototype.write = function(stuff)
 				this.esc_state_ = 2;
 				this.debug("write:: set escape state: 2");
 				break;
+			    case ']':
+			    case 'P':
+				this.esc_state_ = 7;
+				this.debug("write:: set escape state: 7");
+				break;
 			    case '=':
 				/* Set keypade mode (ignored) */
 				this.debug("write:: set keypade mode: ignored");
@@ -903,6 +908,28 @@ VT100.prototype.write = function(stuff)
 			this.esc_state_ = 0;
 			this.debug("write:: set escape state: 0");
 			break;
+		    case 7: // DCS, OSC
+			switch (ch) {
+				case '\x07': // BEL
+				case '\x9c': // ST
+					this.esc_state_ = 0;
+					this.debug("write:: set escape state: 0");
+					break;
+				case '\x1b': // ST
+					this.esc_state = 8;
+					this.debug("write:: set escape state: 8");
+					break;
+			}
+		    case 8: //  Maybe in ST
+			switch (ch) {
+				case '\x5c':
+					this.esc_state = 0;
+					this.debug("write:: set escape state: 0");
+					break;
+				default:
+					this.esc_state = 7;
+					break;
+			}
 		}
 	}
 	this.refresh();