From 9aab3038cc41b5f621d545df8302fdd7f957aa49 Mon Sep 17 00:00:00 2001
From: Luke Howard <lukeh@padl.com>
Date: Sat, 10 Dec 2011 20:39:17 +1100
Subject: [PATCH] InitOnceExecuteOnce not present on XP

---
 mech_eap/util.h        |  8 +++-----
 mech_eap/util_attr.cpp | 14 ++++++++++++++
 2 files changed, 17 insertions(+), 5 deletions(-)

diff --git a/mech_eap/util.h b/mech_eap/util.h
index 4f54d41..23d6ff8 100644
--- a/mech_eap/util.h
+++ b/mech_eap/util.h
@@ -816,14 +816,12 @@ verifyTokenHeader(OM_uint32 *minor,
 #define GSSEAP_MUTEX_DESTROY(m)         DeleteCriticalSection((m))
 #define GSSEAP_MUTEX_LOCK(m)            EnterCriticalSection((m))
 #define GSSEAP_MUTEX_UNLOCK(m)          LeaveCriticalSection((m))
-#define GSSEAP_ONCE_LEAVE		do { return TRUE; } while (0)
 
 /* Thread-local is handled separately */
 
-#define GSSEAP_THREAD_ONCE              INIT_ONCE
-#define GSSEAP_ONCE_CALLBACK(cb)        BOOL CALLBACK cb(PINIT_ONCE InitOnce, PVOID Parameter, PVOID *Context)
-#define GSSEAP_ONCE(o, i)               InitOnceExecuteOnce((o), (i), NULL, NULL)
-#define GSSEAP_ONCE_INITIALIZER         INIT_ONCE_STATIC_INIT
+/* Once is handled separately because INIT_ONCE is only on Vista and above */
+#define GSSEAP_ONCE_LEAVE
+#define GSSEAP_ONCE_CALLBACK(cb)        void CALLBACK cb(void)
 
 #else
 
diff --git a/mech_eap/util_attr.cpp b/mech_eap/util_attr.cpp
index 3bfe785..d3c99d3 100644
--- a/mech_eap/util_attr.cpp
+++ b/mech_eap/util_attr.cpp
@@ -43,8 +43,12 @@
 #include <new>
 
 /* lazy initialisation */
+#ifdef WIN32
+static volatile OM_uint32 gssEapAttrProvidersInitStatus = GSS_S_UNAVAILABLE;
+#else
 static GSSEAP_THREAD_ONCE gssEapAttrProvidersInitOnce = GSSEAP_ONCE_INITIALIZER;
 static OM_uint32 gssEapAttrProvidersInitStatus = GSS_S_UNAVAILABLE;
+#endif
 
 GSSEAP_ONCE_CALLBACK(gssEapAttrProvidersInitInternal)
 {
@@ -74,7 +78,12 @@ cleanup:
     GSSEAP_ASSERT(major == GSS_S_COMPLETE);
 #endif
 
+#ifdef WIN32
+    InterlockedCompareExchangeRelease(&gssEapAttrProvidersInitStatus,
+                                      major, GSS_S_UNAVAILABLE);
+#else
     gssEapAttrProvidersInitStatus = major;
+#endif
 
     GSSEAP_ONCE_LEAVE;
 }
@@ -82,7 +91,12 @@ cleanup:
 static OM_uint32
 gssEapAttrProvidersInit(OM_uint32 *minor)
 {
+#ifdef WIN32
+    if (gssEapAttrProvidersInitStatus == GSS_S_UNAVAILABLE)
+        gssEapAttrProvidersInitInternal();
+#else
     GSSEAP_ONCE(&gssEapAttrProvidersInitOnce, gssEapAttrProvidersInitInternal);
+#endif
 
     if (GSS_ERROR(gssEapAttrProvidersInitStatus))
         *minor = GSSEAP_NO_ATTR_PROVIDERS;
-- 
2.1.4