Improve Visual Studio detection

The new COM API is expected to work on Visual Studio 2017 and newer
installations.

.gitignore

@@ -5,3 +5,4 @@
 *.user
 /src/.vs
 /src/*.opensdf
+/src/packages

src/cv2pdb.vcxproj

@@ -208,8 +208,18 @@
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">true</ExcludedFromBuild>
     </MASM>
   </ItemGroup>
+  <ItemGroup>
+    <None Include="packages.config" />
+  </ItemGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
   <ImportGroup Label="ExtensionTargets">
     <Import Project="$(VCTargetsPath)\BuildCustomizations\masm.targets" />
+    <Import Project="packages\Microsoft.VisualStudio.Setup.Configuration.Native.1.16.30\build\native\Microsoft.VisualStudio.Setup.Configuration.Native.targets" Condition="Exists('packages\Microsoft.VisualStudio.Setup.Configuration.Native.1.16.30\build\native\Microsoft.VisualStudio.Setup.Configuration.Native.targets')" />
   </ImportGroup>
+  <Target Name="EnsureNuGetPackageBuildImports" BeforeTargets="PrepareForBuild">
+    <PropertyGroup>
+      <ErrorText>This project references NuGet package(s) that are missing on this computer. Enable NuGet Package Restore to download them.  For more information, see http://go.microsoft.com/fwlink/?LinkID=322105. The missing file is {0}.</ErrorText>
+    </PropertyGroup>
+    <Error Condition="!Exists('packages\Microsoft.VisualStudio.Setup.Configuration.Native.1.16.30\build\native\Microsoft.VisualStudio.Setup.Configuration.Native.targets')" Text="$([System.String]::Format('$(ErrorText)', 'packages\Microsoft.VisualStudio.Setup.Configuration.Native.1.16.30\build\native\Microsoft.VisualStudio.Setup.Configuration.Native.targets'))" />
+  </Target>
 </Project>

src/main.cpp

@@ -122,6 +122,8 @@ int T_main(int argc, TCHAR* argv[])
 	const TCHAR* pdbref = 0;
 	bool debug = false;
 
+	CoInitialize(nullptr);
+
 	while (argc > 1 && argv[1][0] == '-')
 	{
 		argv++;

src/mspdb.cpp

@@ -6,7 +6,14 @@
 
 #include "mspdb.h"
 
+#include <atlstr.h>
+#include <comdef.h>
 #include <windows.h>
+#include <Setup.Configuration.h>
+
+_COM_SMARTPTR_TYPEDEF(ISetupConfiguration, __uuidof(ISetupConfiguration));
+_COM_SMARTPTR_TYPEDEF(ISetupInstance, __uuidof(ISetupInstance));
+_COM_SMARTPTR_TYPEDEF(IEnumSetupInstances, __uuidof(IEnumSetupInstances));
 
 #pragma comment(lib, "rpcrt4.lib")
 
@@ -83,24 +90,31 @@ bool tryLoadMsPdb(const char* version, const char* mspdb, const char* path = 0)
 
 bool tryLoadMsPdbVS2017(const char* mspdb, const char* path = 0)
 {
-	const char* key = "SOFTWARE\\Microsoft\\VisualStudio\\SxS\\VS7";
-
-	HKEY hkey;
-	if (RegOpenKeyExA(HKEY_LOCAL_MACHINE, key, 0, KEY_OPEN_FLAGS, &hkey) != ERROR_SUCCESS)
+	ISetupConfigurationPtr query;
+	ISetupInstancePtr instance;
+	IEnumSetupInstancesPtr instances;
+	BSTR installDir;
+	unsigned long fetched;
+
+	auto result = query.CreateInstance(__uuidof(SetupConfiguration));
+	if ((FAILED(result) && result != REGDB_E_CLASSNOTREG) || FAILED(query->EnumInstances(&instances)))
 		return false;
 
-	char installDir[260];
-	DWORD size = sizeof(installDir);
-	bool rc = RegQueryValueExA(hkey, "15.0", 0, 0, (LPBYTE)installDir, &size) == ERROR_SUCCESS;
-	RegCloseKey(hkey);
-	if(!rc)
-		return false;
+	while (!modMsPdb)
+	{
+		if (FAILED(instances->Next(1, &instance, &fetched)) || !fetched)
+			return false;
 
-	strncat(installDir, "Common7\\IDE\\", 260);
-	strncat(installDir, mspdb, 260);
+		if (FAILED(instance->GetInstallationPath(&installDir)))
+			continue;
 
-	tryLoadLibrary(installDir);
-	return modMsPdb != 0;
+		CStringA modpath = installDir;
+		modpath += "\\Common7\\IDE\\";
+		modpath += mspdb;
+		tryLoadLibrary(modpath);
+	}
+
+	return true;
 }
 
 #ifdef _M_X64

src/packages.config

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<packages>
+  <package id="Microsoft.VisualStudio.Setup.Configuration.Native" version="1.16.30" targetFramework="native" developmentDependency="true" />
+</packages>