Add conditional compilation for windows and posix functions.

This adds a Windows-specific versions of several symbols from libcrypto
and openssl(1).

apps/apps_win.c

@@ -0,0 +1,29 @@
+/*
+ * Public domain
+ *
+ * Dongsheng Song <dongsheng.song@gmail.com>
+ * Brent Cook <bcook@openbsd.org>
+ */
+
+#include <windows.h>
+
+#include "apps.h"
+
+double
+app_tminterval(int stop, int usertime)
+{
+	static unsigned __int64 tmstart;
+	union {
+		unsigned __int64 u64;
+		FILETIME ft;
+	} ct, et, kt, ut;
+
+	GetProcessTimes(GetCurrentProcess(), &ct.ft, &et.ft, &kt.ft, &ut.ft);
+
+	if (stop == TM_START) {
+		tmstart = ut.u64 + kt.u64;
+	} else {
+		return (ut.u64 + kt.u64 - tmstart) / (double) 10000000;
+	}
+	return 0;
+}