compat/timer-resolution: don't include windows.h in header

1 files changed, 44 insertions, 1 deletions

diff --git a/compat/timer-resolution.hpp b/compat/timer-resolution.hpp
index 5db877c0..8c18a600 100644
--- a/compat/timer-resolution.hpp
+++ b/compat/timer-resolution.hpp
@@ -3,14 +3,57 @@
 #if defined _WIN32
 #   include "export.hpp"
 
+#include <type_traits>
+
+namespace timer_impl
+{
+
+// cf. https://msdn.microsoft.com/en-us/library/windows/desktop/aa383751%28v=vs.85%29.aspx?f=255&MSPPError=-2147217396
+// for NTSTATUS, see http://stackoverflow.com/questions/3378622/how-to-understand-the-ntstatus-nt-success-typedef-in-windows-ddk
+
+using ulong_ = unsigned long;
+using long_ = long;
+using byte_ = unsigned char;
+using boolean_ = byte_;
+
+using true_ = std::integral_constant<int, 1>;
+
+using fail_ = std::integral_constant<byte_, byte_(-1)>;
+
+// cf. http://stackoverflow.com/questions/3378622/how-to-understand-the-ntstatus-nt-success-typedef-in-windows-ddk
+
+// typedef __success(return >= 0) LONG NTSTATUS;
+
+// __success(expr) T f() :  indicates whether function f succeeded or
+// not. If is true at exit, all the function's guarantees (as given
+// by other annotations) must hold. If is false at exit, the caller
+// should not expect any of the function's guarantees to hold. If not used,
+// the function must always satisfy its guarantees. Added automatically to
+// functions that indicate success in standard ways, such as by returning an
+// HRESULT.
+
+using ntstatus_ = long_;
+
+// finally what we want
+// this is equivalent to typedef syntax
+
+using funptr_NtSetTimerResolution = ntstatus_ (__stdcall *)(ulong_, boolean_, ulong_*);
+
+// RAII wrapper
+
 class OTR_COMPAT_EXPORT timer_resolution final
 {
-    unsigned long old_value;
+    ulong_ old_value;
 
 public:
     timer_resolution(int msecs);
     ~timer_resolution();
 };
+
+}
+
+using timer_impl::timer_resolution;
+
 #else
 struct timer_resolution final
 {