Add NSIS installer scripting language

samples/NSIS/x64.nsh

@@ -0,0 +1,54 @@
+; ---------------------
+;       x64.nsh
+; ---------------------
+;
+; A few simple macros to handle installations on x64 machines.
+;
+; RunningX64 checks if the installer is running on x64.
+;
+;   ${If} ${RunningX64}
+;     MessageBox MB_OK "running on x64"
+;   ${EndIf}
+;
+; DisableX64FSRedirection disables file system redirection.
+; EnableX64FSRedirection enables file system redirection.
+;
+;   SetOutPath $SYSDIR
+;   ${DisableX64FSRedirection}
+;   File some.dll # extracts to C:\Windows\System32
+;   ${EnableX64FSRedirection}
+;   File some.dll # extracts to C:\Windows\SysWOW64
+;
+
+!ifndef ___X64__NSH___
+!define ___X64__NSH___
+
+!include LogicLib.nsh
+
+!macro _RunningX64 _a _b _t _f
+  !insertmacro _LOGICLIB_TEMP
+  System::Call kernel32::GetCurrentProcess()i.s
+  System::Call kernel32::IsWow64Process(is,*i.s)
+  Pop $_LOGICLIB_TEMP
+  !insertmacro _!= $_LOGICLIB_TEMP 0 `${_t}` `${_f}`
+!macroend
+
+!define RunningX64 `"" RunningX64 ""`
+
+!macro DisableX64FSRedirection
+
+  System::Call kernel32::Wow64EnableWow64FsRedirection(i0)
+
+!macroend
+
+!define DisableX64FSRedirection "!insertmacro DisableX64FSRedirection"
+
+!macro EnableX64FSRedirection
+
+  System::Call kernel32::Wow64EnableWow64FsRedirection(i1)
+
+!macroend
+
+!define EnableX64FSRedirection "!insertmacro EnableX64FSRedirection"
+
+!endif # !___X64__NSH___