roken: Windows version support helpers

Add helper functions for determining the version of Windows upon which we are
running.

lib/roken/NTMakefile

@@ -177,6 +177,7 @@ INCFILES = 			\
 !ifndef HAVE_STDINT_H
 	$(INCDIR)\stdint.h	\
 !endif
+	$(INCDIR)\versionsupport.h	\
 	$(INCDIR)\xdbm.h
 
 clean::

lib/roken/rand.c

@@ -36,33 +36,7 @@
 
 #ifdef HAVE_WIN32_RAND_S
 static int hasRand_s = 1;
-
-// The Following is BackPorted from VersionHelpers.h in the 10.0.15063.0 SDK
-static FORCEINLINE BOOL
-IsWindowsVersionOrGreater(WORD wMajorVersion, WORD wMinorVersion, WORD wServicePackMajor)
-{
-	OSVERSIONINFOEXW osvi ={ sizeof(osvi), 0, 0, 0, 0,{ 0 }, 0, 0 };
-	DWORDLONG        const dwlConditionMask = VerSetConditionMask(
-		VerSetConditionMask(
-			VerSetConditionMask(
-				0, VER_MAJORVERSION, VER_GREATER_EQUAL),
-			VER_MINORVERSION, VER_GREATER_EQUAL),
-		VER_SERVICEPACKMAJOR, VER_GREATER_EQUAL);
-
-	osvi.dwMajorVersion = wMajorVersion;
-	osvi.dwMinorVersion = wMinorVersion;
-	osvi.wServicePackMajor = wServicePackMajor;
-
-	return VerifyVersionInfoW(&osvi, VER_MAJORVERSION | VER_MINORVERSION | VER_SERVICEPACKMAJOR, dwlConditionMask) != FALSE;
-}
-
-static FORCEINLINE BOOL
-IsWindowsXPOrGreater()
-{
-	// Assume that _WIN32_WINNT_WINXP (0x0501) not available so use contants.
-	return IsWindowsVersionOrGreater(5, 1, 0);
-}
-
+#include "versionsupport.h"
 #endif
 
 void ROKEN_LIB_FUNCTION

lib/roken/versionsupport.h

@@ -0,0 +1,139 @@
+/*
+ * Copyright (c) 2018-2019, AuriStor, Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in
+ *   the documentation and/or other materials provided with the
+ *   distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#ifndef _VERSIONSUPPORT_H_
+#define _VERSIONSUPPORT_H_ 1
+
+/*
+ * IsWindowsVersionOrGreater() is provided by Windows SDK 8.1 or greater.
+ * As AuriStorFS supports building with SDK 7.0 and greater we must
+ * provide our own.  VerifyVersionInfoW() is present on Windows XP and
+ * later.
+ */
+
+#ifndef _WIN32_WINNT_WIN7
+#define _WIN32_WINNT_WIN7     0x0601
+#endif
+
+#ifndef _WIN32_WINNT_WIN8
+#define _WIN32_WINNT_WIN8     0x0602
+#endif
+
+#ifndef _WIN32_WINNT_WINBLUE
+#define _WIN32_WINNT_WINBLUE  0x0603
+#endif
+
+/* Based upon VersionHelpers.h */
+FORCEINLINE BOOL
+IsWindowsVersionOrGreater(WORD wMajorVersion,
+			  WORD wMinorVersion,
+			  WORD wServicePackMajor)
+{
+    OSVERSIONINFOEXW osvi;
+    DWORDLONG        dwlConditionMask = 0;
+
+    dwlConditionMask = VerSetConditionMask(dwlConditionMask,
+					   VER_MAJORVERSION,
+					   VER_GREATER_EQUAL);
+    dwlConditionMask = VerSetConditionMask(dwlConditionMask,
+					   VER_MINORVERSION,
+					   VER_GREATER_EQUAL);
+    dwlConditionMask = VerSetConditionMask(dwlConditionMask,
+					   VER_SERVICEPACKMAJOR,
+					   VER_GREATER_EQUAL);
+
+    memset(&osvi, 0, sizeof(OSVERSIONINFOEXW));
+    osvi.dwOSVersionInfoSize = sizeof(OSVERSIONINFOEXW);
+    osvi.dwMajorVersion = wMajorVersion;
+    osvi.dwMinorVersion = wMinorVersion;
+    osvi.wServicePackMajor = wServicePackMajor;
+
+    return VerifyVersionInfoW(&osvi,
+			      (VER_MAJORVERSION |
+			       VER_MINORVERSION |
+			       VER_SERVICEPACKMAJOR),
+			      dwlConditionMask);
+}
+
+FORCEINLINE BOOL
+IsWindowsXPOrGreater(VOID)
+{
+    return IsWindowsVersionOrGreater(HIBYTE(_WIN32_WINNT_WINXP),
+				     LOBYTE(_WIN32_WINNT_WINXP),
+				     0);
+}
+
+FORCEINLINE BOOL
+IsWindows7OrGreater(VOID)
+{
+    return IsWindowsVersionOrGreater(HIBYTE(_WIN32_WINNT_WIN7),
+				     LOBYTE(_WIN32_WINNT_WIN7),
+				     0);
+}
+
+FORCEINLINE BOOL
+IsWindows8OrGreater(VOID)
+{
+    return IsWindowsVersionOrGreater(HIBYTE(_WIN32_WINNT_WIN8),
+				     LOBYTE(_WIN32_WINNT_WIN8),
+				     0);
+}
+
+FORCEINLINE BOOL
+IsWindows8Point1OrGreater(VOID)
+{
+    return IsWindowsVersionOrGreater(HIBYTE(_WIN32_WINNT_WINBLUE),
+				     LOBYTE(_WIN32_WINNT_WINBLUE),
+				     0);
+}
+
+#define IS_WINDOWS_VERSION_OR_GREATER_CACHED(fn)		\
+								\
+FORCEINLINE BOOL						\
+fn##Cached(VOID)						\
+{								\
+    static LONG lIsVersionOrGreater = -1;			\
+								\
+    if (lIsVersionOrGreater == -1) {				\
+	LONG lResult = fn();					\
+	InterlockedCompareExchangeRelease(&lIsVersionOrGreater, \
+					  lResult, -1);		\
+    }								\
+								\
+    return lIsVersionOrGreater == 1;				\
+}
+
+IS_WINDOWS_VERSION_OR_GREATER_CACHED(IsWindowsXPOrGreater)
+IS_WINDOWS_VERSION_OR_GREATER_CACHED(IsWindows7OrGreater)
+IS_WINDOWS_VERSION_OR_GREATER_CACHED(IsWindows8OrGreater)
+IS_WINDOWS_VERSION_OR_GREATER_CACHED(IsWindows8Point1OrGreater)
+
+#endif /* _VERSIONSUPPORT_H_ */