From dab42a1afb881b8e7d0a7b50ae529545b45ecf5b Mon Sep 17 00:00:00 2001
From: saurtron <saurtron@riseup.net>
Date: Wed, 11 Dec 2024 14:38:54 +0100
Subject: [PATCH] get proper size for osFontsDir

Co-authored-by: sprunk <spr.ng@o2.pl>
---
 rts/Rendering/Fonts/CFontTexture.cpp | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/rts/Rendering/Fonts/CFontTexture.cpp b/rts/Rendering/Fonts/CFontTexture.cpp
index a638eef365..7a66a7a4d8 100644
--- a/rts/Rendering/Fonts/CFontTexture.cpp
+++ b/rts/Rendering/Fonts/CFontTexture.cpp
@@ -150,8 +150,10 @@ class FtLibraryHandler {
 			// and system fonts included. also linux actually has system config files that can be used by fontconfig.
 
 			#ifdef _WIN32
-			std::array<char, 4096> osFontsDir;
-			ExpandEnvironmentStrings("%WINDIR%\\fonts", osFontsDir.data(), osFontsDir.size()); // expands %HOME% etc.
+			static constexpr auto winFontPath = "%WINDIR%\\fonts";
+			const int neededSize = ExpandEnvironmentStrings(winFontPath, nullptr, 0);
+			std::vector <char> osFontsDir (neededSize);
+			ExpandEnvironmentStrings(winFontPath, osFontsDir.data(), osFontsDir.size());
 			static constexpr const char* configFmt = R"(<fontconfig><dir>%s</dir><cachedir>fontcache</cachedir></fontconfig>)";
 			std::string configFmtVar = fmt::sprintf(configFmt, osFontsDir.data());
 			#else