1 files changed, 73 insertions, 0 deletions

diff --git a/mps/code/th.h b/mps/code/th.h
new file mode 100644
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+++ b/mps/code/th.h
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+/*  impl.h.th: THREAD MANAGER
+ *
+ *  $HopeName$
+ *  Copyright (C) 1995 Harlequin Limited.  All rights reserved.
+ *
+ *  .purpose: Provides thread suspension facilities to the shield.
+ *  See design.mps.thread-manager.  Each thread has to be
+ *  individually registered and deregistered with an arena.
+ */
+
+#ifndef th_h
+#define th_h
+
+#include "mpmtypes.h"
+#include "ring.h"
+
+
+#define ThreadSig       ((Sig)0x519286ED) /* SIGnature THREaD */
+
+extern Bool ThreadCheck(Thread thread);
+
+
+/*  ThreadCheckSimple
+ *
+ *  Simple thread-safe check of a thread object.
+ */
+
+extern Bool ThreadCheckSimple(Thread thread);
+
+
+extern Res ThreadDescribe(Thread thread, mps_lib_FILE *stream);
+
+
+/*  Register/Deregister
+ *
+ *  Explicitly register/deregister a thread on the arena threadRing.
+ *  Register returns a "Thread" value which needs to be used
+ *  for deregistration.
+ *
+ *  Threads must not be multiply registered in the same arena.
+ */
+
+extern Res ThreadRegister(Thread *threadReturn, Arena arena);
+
+extern void ThreadDeregister(Thread thread, Arena arena);
+
+
+/*  ThreadRingSuspend/Resume
+ *
+ *  These functions suspend/resume the threads on the ring.
+ *  If the current thread is among them, it is not suspended,
+ *  nor is any attempt to resume it made.
+ */
+
+extern void ThreadRingSuspend(Ring threadRing);
+extern void ThreadRingResume(Ring threadRing);
+
+
+/*  ThreadRingThread 
+ *
+ *  Return the thread from an element of the Arena's
+ *  thread ring.
+ */
+
+extern Thread ThreadRingThread(Ring threadRing);
+
+
+extern Arena ThreadArena(Thread thread);
+
+extern Res ThreadScan(ScanState ss, Thread thread, void *stackBot);
+
+
+#endif /* th_h */