diff --git a/lib/krb5/heim_threads.h b/lib/krb5/heim_threads.h
new file mode 100644
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+++ b/lib/krb5/heim_threads.h
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+/*
+ * Copyright (c) 2003 Kungliga Tekniska Högskolan
+ * (Royal Institute of Technology, Stockholm, Sweden). 
+ * All rights reserved. 
+ *
+ * Redistribution and use in source and binary forms, with or without 
+ * modification, are permitted provided that the following conditions 
+ * are met: 
+ *
+ * 1. Redistributions of source code must retain the above copyright 
+ *    notice, this list of conditions and the following disclaimer. 
+ *
+ * 2. 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. 
+ *
+ * 3. Neither the name of the Institute nor the names of its contributors 
+ *    may be used to endorse or promote products derived from this software 
+ *    without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE 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 INSTITUTE 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. 
+ */
+
+/* $Id$ */
+
+/*
+ * Provide wrapper macros for thread synchronization primitives so we
+ * can use native thread functions for those operating system that
+ * supports it.
+ *
+ * This is so libkrb5.so (or more importantly, libgssapi.so) can have
+ * thread support while the program that that dlopen(3)s the library
+ * don't need to be linked to libpthread.
+ */
+
+#ifndef HEIM_THREADS_H
+#define HEIM_THREADS_H 1
+
+/* assume headers already included */
+
+#if defined(__NetBSD__) && __NetBSD_Version__ >= 106120000
+
+/* 
+ * NetBSD have a thread lib that we can use that part of libc that
+ * works regardless if application are linked to pthreads or not.
+ */
+#include <threadlib.h>
+
+#define HEIMDAL_MUTEX mutex_t
+#define HEIMDAL_MUTEX_INITIALIZER MUTEX_INITIALIZER
+#define HEIMDAL_MUTEX_init(m) mutex_init(m)
+#define HEIMDAL_MUTEX_lock(m) mutex_lock(m)
+#define HEIMDAL_MUTEX_unlock(m) mutex_unlock(m)
+#define HEIMDAL_MUTEX_destroy(m) mutex_destroy(m)
+
+/* XXX hole for Jacques to fill in :)
+   #el if defined(__FreeBSD_version) &&  */
+
+#elif define(ENABLE_PTHREAD_SUPPORT)
+
+#define HEIMDAL_MUTEX pthread_mutex_t
+#define HEIMDAL_MUTEX_INITIALIZER PTHREAD_MUTEX_INITIALIZER
+#define HEIMDAL_MUTEX_init(m) pthread_mutex_init(m)
+#define HEIMDAL_MUTEX_lock(m) pthread_mutex_lock(m)
+#define HEIMDAL_MUTEX_unlock(m) pthread_mutex_unlock(m)
+#define HEIMDAL_MUTEX_destroy(m) pthread_mutex_destroy(m)
+
+#elif defined(HEIMDAL_DEBUG_THREADS) || 1
+
+/* no threads support, just do consistency checks */
+#include <stdlib.h>
+
+#define HEIMDAL_MUTEX int
+#define HEIMDAL_MUTEX_INITIALIZER 0
+#define HEIMDAL_MUTEX_init(m)  do { (*(m)) = 0; } while(0)
+#define HEIMDAL_MUTEX_lock(m)  do { if ((*(m))++ != 0) abort(); } while(0)
+#define HEIMDAL_MUTEX_unlock do { if ((*(m))-- != 1) abort(); } while(0)
+#define HEIMDAL_MUTEX_destroy do {if ((*(m)) != 0) abort(); } while(0)
+
+#else /* no thread support, no debug case */
+
+#define HEIMDAL_MUTEX int
+#define HEIMDAL_MUTEX_INITIALIZER 0
+#define HEIMDAL_MUTEX_init(m)  do { } while(0)
+#define HEIMDAL_MUTEX_lock(m)  do { } while(0)
+#define HEIMDAL_MUTEX_unlock do { } while(0)
+#define HEIMDAL_MUTEX_destroy do { } while(0)
+
+#endif /* no thread support */
+
+#endif /* HEIM_THREADS_H */