From 28bf2d637432ac5acff2a7f585820a7100074150 Mon Sep 17 00:00:00 2001
From: Bananymous <oskari.alaranta@bananymous.com>
Date: Wed, 23 Apr 2025 06:10:38 +0300
Subject: [PATCH] Kernel/Terminal: Add support for ANSI DSR

---
 kernel/kernel/Terminal/VirtualTTY.cpp    | 17 +++++++++++++++--
 userspace/programs/Terminal/Terminal.cpp | 12 +++++++++++-
 2 files changed, 26 insertions(+), 3 deletions(-)

diff --git a/kernel/kernel/Terminal/VirtualTTY.cpp b/kernel/kernel/Terminal/VirtualTTY.cpp
index 70ea31f4..b5d94d57 100644
--- a/kernel/kernel/Terminal/VirtualTTY.cpp
+++ b/kernel/kernel/Terminal/VirtualTTY.cpp
@@ -360,11 +360,24 @@ namespace Kernel
 					return reset_ansi();
 				}
 				reset_ansi();
-				dprintln_if(DEBUG_VTTY, "invalid ANSI CSI ?{}{}", m_ansi_state.nums[0], (char)ch);
+				dprintln_if(DEBUG_VTTY, "invalid ANSI CSI character {}", static_cast<char>(ch));
+				return;
+			case 'n':
+				if (m_ansi_state.nums[0] == 6)
+				{
+					char buffer[2 + 10 + 1 + 10 + 1];
+					size_t len = 0;
+					BAN::Formatter::print([&](char ch) { buffer[len++] = ch; }, "\e[{};{}R", m_row + 1, m_column + 1);
+					for (size_t i = 0; i < len; i++)
+						handle_input_byte(buffer[i]);
+					return reset_ansi();
+				};
+				reset_ansi();
+				dprintln_if(DEBUG_VTTY, "Unsupported ANSI CSI character n");
 				return;
 			default:
 				reset_ansi();
-				dprintln_if(DEBUG_VTTY, "Unsupported ANSI CSI character {}", ch);
+				dprintln_if(DEBUG_VTTY, "Unsupported ANSI CSI character {}", static_cast<char>(ch));
 				return;
 		}
 	}
diff --git a/userspace/programs/Terminal/Terminal.cpp b/userspace/programs/Terminal/Terminal.cpp
index 96d41bbc..b4864c91 100644
--- a/userspace/programs/Terminal/Terminal.cpp
+++ b/userspace/programs/Terminal/Terminal.cpp
@@ -517,11 +517,21 @@ Rectangle Terminal::handle_csi(char ch)
 		case 'l':
 			if (!m_csi_info.question || m_csi_info.fields[0] != 25)
 			{
-				dprintln("invalid ANSI CSI ?{}{}", m_csi_info.fields[0], (char)ch);
+				dprintln("unsupported ANSI CSI {}", ch);
 				break;
 			}
 			m_cursor_shown = (ch == 'h');
 			break;
+		case 'n':
+			if (m_csi_info.fields[0] != 6)
+			{
+				dprintln("unsupported ANSI CSI n");
+				break;
+			}
+			char buffer[2 + 10 + 1 + 10 + 2];
+			sprintf(buffer, "\e[%u;%uR", m_cursor.y + 1, m_cursor.x + 1);
+			write(m_shell_info.pts_master, buffer, strlen(buffer));
+			break;
 		default:
 			dprintln("TODO: CSI {}", ch);
 			break;