From d0f979ecd9a8e7eeb879af4ff3f7cee1968f3b4f Mon Sep 17 00:00:00 2001
From: GreyMerlin <GreyMerlin@gmail.com>
Date: Wed, 25 Jul 2018 19:20:17 -0700
Subject: [PATCH] Eliminate use of deprecated `GetVersionEx()`

* Add "Win_VersionHelper.h" to implement the proper modern runtime
checking for the Windows version.

* Unrelated: <mbstring.h> is useless in a UNICODE application.
---
 Src/DirTravel.cpp                |  8 ++------
 Src/Merge.vs2017.vcxproj         |  1 +
 Src/Merge.vs2017.vcxproj.filters |  3 +++
 Src/Win_VersionHelper.h          | 39 +++++++++++++++++++++++++++++++++++++++
 4 files changed, 45 insertions(+), 6 deletions(-)
 create mode 100644 Src/Win_VersionHelper.h

diff --git a/Src/DirTravel.cpp b/Src/DirTravel.cpp
index 93af3f1b2..defcc3ef0 100644
--- a/Src/DirTravel.cpp
+++ b/Src/DirTravel.cpp
@@ -12,12 +12,12 @@
 #include <Poco/Timestamp.h>
 #include <windows.h>
 #include <tchar.h>
-#include <mbstring.h>
 #include "TFile.h"
 #include "UnicodeString.h"
 #include "DirItem.h"
 #include "unicoder.h"
 #include "paths.h"
+#include "Win_VersionHelper.h"
 
 using Poco::DirectoryIterator;
 using Poco::Timestamp;
@@ -83,11 +83,7 @@ static void LoadFiles(const String& sDir, DirItemArray * dirs, DirItemArray * fi
 
 	WIN32_FIND_DATA ff;
 	HANDLE h;
-	OSVERSIONINFO vi;
-	vi.dwOSVersionInfoSize = sizeof(vi);
-	GetVersionEx(&vi);
-
-	if (vi.dwMajorVersion * 10 + vi.dwMinorVersion >= 61)
+	if (IsWin7_OrGreater())	// (also 'Windows Server 2008 R2' and greater) for FIND_FIRST_EX_LARGE_FETCH
 		h = FindFirstFileEx(TFile(sPattern).wpath().c_str(), FindExInfoBasic, &ff, FindExSearchNameMatch, NULL, FIND_FIRST_EX_LARGE_FETCH);
 	else
 		h = FindFirstFile(TFile(sPattern).wpath().c_str(), &ff);
diff --git a/Src/Merge.vs2017.vcxproj b/Src/Merge.vs2017.vcxproj
index b0d552fd3..cc3e92130 100644
--- a/Src/Merge.vs2017.vcxproj
+++ b/Src/Merge.vs2017.vcxproj
@@ -1129,6 +1129,7 @@
     <ClInclude Include="Common\VersionInfo.h" />
     <ClInclude Include="VSSHelper.h" />
     <ClInclude Include="VssPromptDlg.h" />
+    <ClInclude Include="Win_VersionHelper.h" />
     <ClInclude Include="WMGotoDlg.h" />
     <ClInclude Include="diffutils\lib\cmpbuf.h" />
     <ClInclude Include="diffutils\config.h" />
diff --git a/Src/Merge.vs2017.vcxproj.filters b/Src/Merge.vs2017.vcxproj.filters
index c0fcb89fc..226495562 100644
--- a/Src/Merge.vs2017.vcxproj.filters
+++ b/Src/Merge.vs2017.vcxproj.filters
@@ -1449,6 +1449,9 @@
     <ClInclude Include="..\Externals\gtest\include\gtest\gtest.h">
       <Filter>MergeTest</Filter>
     </ClInclude>
+    <ClInclude Include="Win_VersionHelper.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <None Include="res\binarydiff.ico">
diff --git a/Src/Win_VersionHelper.h b/Src/Win_VersionHelper.h
new file mode 100644
index 000000000..746dd4b77
--- /dev/null
+++ b/Src/Win_VersionHelper.h
@@ -0,0 +1,39 @@
+/** 
+ * @file  Win_VersionHelper.h
+ *
+ * @brief Defines quick-and-dirty runtime Windows version checking.
+
+ * All we need in WinMerge is `IsWin7_OrGreater()`
+ * But other possibilities (and slightly different implementation) can be seen in ...
+ *		'C:\Program Files (x86)\Windows Kits\10\Include\10.0.17134.0\um\VersionHelpers.h'
+ *
+ */
+
+#pragma once
+
+#include <windows.h>
+
+inline bool
+IsWinVer_OrGreater(WORD wVersion, WORD wServicePack = 0)
+{
+	DWORDLONG dwlConditionMask = 0;	
+	VER_SET_CONDITION( dwlConditionMask, VER_MAJORVERSION, VER_GREATER_EQUAL );
+	VER_SET_CONDITION( dwlConditionMask, VER_MINORVERSION, VER_GREATER_EQUAL );
+	VER_SET_CONDITION( dwlConditionMask, VER_SERVICEPACKMAJOR, VER_GREATER_EQUAL );
+
+	OSVERSIONINFOEXW osvi;
+	::ZeroMemory(&osvi, sizeof(OSVERSIONINFOEX));
+	osvi.dwOSVersionInfoSize = sizeof(OSVERSIONINFOEX);
+	osvi.dwMajorVersion = HIBYTE(wVersion);
+	osvi.dwMinorVersion = LOBYTE(wVersion);
+	osvi.wServicePackMajor = wServicePack;
+
+	return VerifyVersionInfoW(&osvi, VER_MAJORVERSION | VER_MINORVERSION | VER_SERVICEPACKMAJOR, dwlConditionMask) != FALSE;
+}
+
+
+inline bool
+IsWin7_OrGreater()
+{
+    return IsWinVer_OrGreater( _WIN32_WINNT_WIN7 );
+}
-- 
2.11.0