From 4e264bd45d6cd7fa7d0d1e93a4aeef55a9cc2371 Mon Sep 17 00:00:00 2001
From: Matt <m.moninger.h@gmail.com>
Date: Sun, 31 Mar 2019 16:52:16 +0200
Subject: [PATCH] Use mutex to protect scrolling banner cache from data race

---
 src/openrct2/drawing/ScrollingText.cpp | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/openrct2/drawing/ScrollingText.cpp b/src/openrct2/drawing/ScrollingText.cpp
index 0d35edea29..a054247a43 100644
--- a/src/openrct2/drawing/ScrollingText.cpp
+++ b/src/openrct2/drawing/ScrollingText.cpp
@@ -17,6 +17,7 @@
 #include "TTF.h"
 
 #include <algorithm>
+#include <mutex>
 
 #pragma pack(push, 1)
 /* size: 0xA12 */
@@ -38,6 +39,7 @@ assert_struct_size(rct_draw_scroll_text, 0xA12);
 static rct_draw_scroll_text _drawScrollTextList[MAX_SCROLLING_TEXT_ENTRIES];
 static uint8_t _characterBitmaps[FONT_SPRITE_GLYPH_COUNT + SPR_G2_GLYPH_COUNT][8];
 static uint32_t _drawSCrollNextIndex = 0;
+static std::mutex _scrollingTextMutex;
 
 static void scrolling_text_set_bitmap_for_sprite(
     utf8* text, int32_t scroll, uint8_t* bitmap, const int16_t* scrollPositionOffsets);
@@ -1472,6 +1474,8 @@ void scrolling_text_invalidate()
  */
 int32_t scrolling_text_setup(paint_session* session, rct_string_id stringId, uint16_t scroll, uint16_t scrollingMode)
 {
+    std::scoped_lock<std::mutex> lock(_scrollingTextMutex);
+
     assert(scrollingMode < MAX_SCROLLING_TEXT_MODES);
 
     rct_drawpixelinfo* dpi = &session->DPI;