From 5b99238fca19e3996e40dc85b3ed082870e118c8 Mon Sep 17 00:00:00 2001
From: Ryan Prichard <ryan.prichard@gmail.com>
Date: Sat, 22 Apr 2017 23:41:22 -0700
Subject: [PATCH] Don't show the cursor if it is outside the console window

Fixes https://github.com/rprichard/winpty/issues/113
---
 src/agent/Scraper.cc  | 28 ++++++++++++++++------------
 src/agent/Scraper.h   |  4 ++--
 src/agent/SmallRect.h |  8 ++++++++
 3 files changed, 26 insertions(+), 14 deletions(-)

diff --git a/src/agent/Scraper.cc b/src/agent/Scraper.cc
index 542d833..21f9c67 100755
--- a/src/agent/Scraper.cc
+++ b/src/agent/Scraper.cc
@@ -432,7 +432,7 @@ WORD Scraper::attributesMask()
 }
 
 void Scraper::directScrapeOutput(const ConsoleScreenBufferInfo &info,
-                                 bool cursorVisible)
+                                 bool consoleCursorVisible)
 {
     const SmallRect windowRect = info.windowRect();
 
@@ -446,11 +446,12 @@ void Scraper::directScrapeOutput(const ConsoleScreenBufferInfo &info,
     const int h = scrapeRect.height();
 
     const Coord cursor = info.cursorPosition();
-    const int cursorColumn = !cursorVisible ? -1 :
-        constrained(0, cursor.X - scrapeRect.Left, w - 1);
-    const int cursorLine = !cursorVisible ? -1 :
-        constrained(0, cursor.Y - scrapeRect.Top, h - 1);
-    if (!cursorVisible) {
+    const bool showTerminalCursor =
+        consoleCursorVisible && scrapeRect.contains(cursor);
+    const int cursorColumn = !showTerminalCursor ? -1 : cursor.X - scrapeRect.Left;
+    const int cursorLine = !showTerminalCursor ? -1 : cursor.Y - scrapeRect.Top;
+
+    if (!showTerminalCursor) {
         m_terminal->hideTerminalCursor();
     }
 
@@ -467,13 +468,13 @@ void Scraper::directScrapeOutput(const ConsoleScreenBufferInfo &info,
         }
     }
 
-    if (cursorVisible) {
+    if (showTerminalCursor) {
         m_terminal->showTerminalCursor(cursorColumn, cursorLine);
     }
 }
 
 bool Scraper::scrollingScrapeOutput(const ConsoleScreenBufferInfo &info,
-                                    bool cursorVisible,
+                                    bool consoleCursorVisible,
                                     bool tentative)
 {
     const Coord cursor = info.cursorPosition();
@@ -605,9 +606,12 @@ bool Scraper::scrollingScrapeOutput(const ConsoleScreenBufferInfo &info,
         std::min(m_dirtyLineCount, windowRect.top() + windowRect.height()) +
             m_scrolledCount;
 
-    const int64_t cursorLine = !cursorVisible ? -1 : cursor.Y + m_scrolledCount;
-    const int cursorColumn = !cursorVisible ? -1 : cursor.X;
-    if (!cursorVisible) {
+    const bool showTerminalCursor =
+        consoleCursorVisible && windowRect.contains(cursor);
+    const int64_t cursorLine = !showTerminalCursor ? -1 : cursor.Y + m_scrolledCount;
+    const int cursorColumn = !showTerminalCursor ? -1 : cursor.X;
+
+    if (!showTerminalCursor) {
         m_terminal->hideTerminalCursor();
     }
 
@@ -636,7 +640,7 @@ bool Scraper::scrollingScrapeOutput(const ConsoleScreenBufferInfo &info,
 
     m_scrapedLineCount = windowRect.top() + m_scrolledCount;
 
-    if (cursorVisible) {
+    if (showTerminalCursor) {
         m_terminal->showTerminalCursor(cursorColumn, cursorLine);
     }
 
diff --git a/src/agent/Scraper.h b/src/agent/Scraper.h
index 48314a6..9c10d80 100755
--- a/src/agent/Scraper.h
+++ b/src/agent/Scraper.h
@@ -73,9 +73,9 @@ private:
                                    ConsoleScreenBufferInfo &finalInfoOut);
     WORD attributesMask();
     void directScrapeOutput(const ConsoleScreenBufferInfo &info,
-                            bool cursorVisible);
+                            bool consoleCursorVisible);
     bool scrollingScrapeOutput(const ConsoleScreenBufferInfo &info,
-                               bool cursorVisible,
+                               bool consoleCursorVisible,
                                bool tentative);
     void syncMarkerText(CHAR_INFO (&output)[SYNC_MARKER_LEN]);
     int findSyncMarker();
diff --git a/src/agent/SmallRect.h b/src/agent/SmallRect.h
index c159346..bad0b88 100644
--- a/src/agent/SmallRect.h
+++ b/src/agent/SmallRect.h
@@ -76,6 +76,14 @@ struct SmallRect : SMALL_RECT
                other.Bottom <= Bottom;
     }
 
+    bool contains(const Coord &other) const
+    {
+        return other.X >= Left &&
+               other.X <= Right &&
+               other.Y >= Top &&
+               other.Y <= Bottom;
+    }
+
     SmallRect intersected(const SmallRect &other) const
     {
         int x1 = std::max(Left, other.Left);