New header testthr.h provides simple threading interface.

Implementations testthrix.c for Unix and testthrw3.c for Windows.
Multi-threaded test cases use the new interface.
Rename lockutw3 to lockut (no longer Windows-specific).
Run multi-threaded test cases on Windows and lockut elsewhere.

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 Change: 185350
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mps/code/testthr.h

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+/* testthr.h: MULTI-THREADED TEST INTERFACE
+ *
+ * $Id: //info.ravenbrook.com/project/mps/master/code/testlib.h#30 $
+ * Copyright (c) 2014 Ravenbrook Limited.  See end of file for license.
+ *
+ * .purpose: Simple interface to threads that makes it possible to
+ * write test cases that are portable between Windows (using the
+ * implementation in testthrw3.c) and Unix (using the implementation
+ * in testthrix.c).
+ */
+
+#ifndef testthr_h
+#define testthr_h
+
+#include "mpstd.h"
+
+
+/* testthr_routine_t -- type of thread routines
+ *
+ * Use the pthread type here and convert back and forth in the Windows
+ * implementation.
+ */
+typedef void *(*testthr_routine_t)(void *);
+
+
+/* testthr_t -- type of thread identifiers
+ *
+ * It is necessary to define it here (even though it requires some
+ * #ifdefs) so that clients can allocate storage for them.
+ */
+
+#if defined(MPS_OS_W3)
+
+#include "mpswin.h"
+
+/* On Windows, a thread is identified by a HANDLE.
+ * <http://msdn.microsoft.com/en-us/library/windows/desktop/aa383751.aspx>
+ * But use a structure so that the thread has somewhere to store its
+ * result for use by testthr_join.
+ */
+typedef struct testthr_t {
+  HANDLE handle;
+  testthr_routine_t start;
+  void *arg;                  /* argument to pass to start */
+  void *result;               /* result returned from start */
+} testthr_t;
+
+#elif defined(MPS_OS_FR) || defined(MPS_OS_LI) || defined(MPS_OS_XC)
+
+#include <pthread.h>
+
+/* In pthreads, a thread is identified by a pthread_t, which is
+ * allowed "to be defined as a structure" [IEEE Std 1003.1, sys/types.h]
+ * <http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/sys_types.h.html>
+ */
+typedef pthread_t testthr_t;
+
+#else
+#error "Unknown platform: can't determine a type for testthr_t."
+#endif
+
+
+/* testthr_create -- create a thread
+ *
+ * Store the identifier of the newly created thread in *thread_o, and
+ * call start, passing arg as the single parameter.
+ */
+
+void testthr_create(testthr_t *thread_o, testthr_routine_t start, void *arg);
+
+
+/* testthr_join -- wait for a thread to complete 
+ *
+ * Suspend execution of the calling thread until the target thread
+ * terminates (if necessary), and if result_o is non-NULL, update
+ * *result_o with the return value of the thread's start.
+ */
+
+void testthr_join(testthr_t *thread, void **result_o);
+
+#endif /* testthr_h */
+
+
+/* C. COPYRIGHT AND LICENSE
+ *
+ * Copyright (C) 2014 Ravenbrook Limited <http://www.ravenbrook.com/>.
+ * All rights reserved.  This is an open source license.  Contact
+ * Ravenbrook for commercial licensing options.
+ * 
+ * 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. Redistributions in any form must be accompanied by information on how
+ * to obtain complete source code for this software and any accompanying
+ * software that uses this software.  The source code must either be
+ * included in the distribution or be available for no more than the cost
+ * of distribution plus a nominal fee, and must be freely redistributable
+ * under reasonable conditions.  For an executable file, complete source
+ * code means the source code for all modules it contains. It does not
+ * include source code for modules or files that typically accompany the
+ * major components of the operating system on which the executable file
+ * runs.
+ * 
+ * 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, FITNESS FOR A PARTICULAR
+ * PURPOSE, OR NON-INFRINGEMENT, ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDERS AND 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.
+ */