improve genminiupnpcstrings.vbs to generate file only if changed

miniupnpc/msvc/genminiupnpcstrings.vbs

@@ -29,8 +29,58 @@ For Each objOperatingSystem in colOperatingSystems
 	os_version = objOperatingSystem.Version
 Next
 
-Dim array
+'Wscript.Echo os_version
 
+Dim array
+needWrite = True
+
+' First Check if the file already contains the right versions
+Err.Clear
+Set f_in = FSO.OpenTextFile(outfile, 1, False)
+If Err.Number = 0 Then
+	old_version = ""
+	old_os_version = ""
+	Do Until f_in.AtEndOfStream
+		line = f_in.ReadLine
+		If Len(line) > 0 Then
+			array = Split(line, " ")
+			If UBound(array) >= 2 And array(0) = "#define" Then
+				If array(1) = "OS_STRING" Then
+					old_os_version = Replace(array(2), Chr(34), "")
+				ElseIf array(1) = "MINIUPNPC_VERSION_STRING" Then
+					old_version = Replace(array(2), Chr(34), "")
+				End if
+			End if
+		End If
+	Loop
+	f_in.Close
+	If old_version = version And old_os_version = "MSWindows/" & os_version Then
+		needWrite = False
+	Else
+		needWrite = True
+	End If
+End If
+
+If Not needWrite Then
+	' check files dates
+	Set fIn1 = FSO.GetFile(versionfile)
+	Set fIn2 = FSO.GetFile(infile)
+	Set fOut = FSO.GetFile(outfile)
+	If DateDiff("s", fIn1.DateLastModified, fOut.DateLastModified) < 0 Then
+		needWrite = True
+	End If
+	If DateDiff("s", fIn2.DateLastModified, fOut.DateLastModified) < 0 Then
+		needWrite = True
+	End If
+End If
+
+If Not needWrite Then
+    ' nothing to do
+	WScript.Quit 0
+End if
+
+' generate the file
+Err.Clear
 Set f_in = FSO.OpenTextFile(infile, 1, False)
 If Err.Number = 0 Then
 	Set f_out = FSO.OpenTextFile(outfile, 2, True) ' 2 = Write

miniupnpc/msvc/miniupnpc_vs2010.vcxproj

@@ -178,6 +178,9 @@
     <ClInclude Include="..\upnperrors.h" />
     <ClInclude Include="..\upnpreplyparse.h" />
   </ItemGroup>
+  <ItemGroup>
+    <None Include="genminiupnpcstrings.vbs" />
+  </ItemGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
   <ImportGroup Label="ExtensionTargets">
   </ImportGroup>

miniupnpc/msvc/miniupnpc_vs2010.vcxproj.filters

@@ -104,5 +104,13 @@
     <Filter Include="headers">
       <UniqueIdentifier>{2b3996de-1bc4-418b-8a83-a5f34fdf0df5}</UniqueIdentifier>
     </Filter>
+    <Filter Include="scripts">
+      <UniqueIdentifier>{45dbc39d-c3ca-4a75-adf0-76070e20415a}</UniqueIdentifier>
+    </Filter>
+  </ItemGroup>
+  <ItemGroup>
+    <None Include="genminiupnpcstrings.vbs">
+      <Filter>scripts</Filter>
+    </None>
   </ItemGroup>
 </Project>