RTS tidyup sweep, first phase

The first phase of this tidyup is focussed on the header files, and in
particular making sure we are exposinng publicly exactly what we need
to, and no more.

 - Rts.h now includes everything that the RTS exposes publicly,
   rather than a random subset of it.

 - Most of the public header files have moved into subdirectories, and
   many of them have been renamed.  But clients should not need to
   include any of the other headers directly, just #include the main
   public headers: Rts.h, HsFFI.h, RtsAPI.h.

 - All the headers needed for via-C compilation have moved into the
   stg subdirectory, which is self-contained.  Most of the headers for
   the rest of the RTS APIs have moved into the rts subdirectory.

 - I left MachDeps.h where it is, because it is so widely used in
   Haskell code.
 
 - I left a deprecated stub for RtsFlags.h in place.  The flag
   structures are now exposed by Rts.h.

 - Various internal APIs are no longer exposed by public header files.

 - Various bits of dead code and declarations have been removed

 - More gcc warnings are turned on, and the RTS code is more
   warning-clean.

 - More source files #include "PosixSource.h", and hence only use
   standard POSIX (1003.1c-1995) interfaces.

There is a lot more tidying up still to do, this is just the first
pass.  I also intend to standardise the names for external RTS APIs
(e.g use the rts_ prefix consistently), and declare the internal APIs
as hidden for shared libraries.

1 files changed, 209 insertions, 0 deletions

diff --git a/includes/rts/OSThreads.h b/includes/rts/OSThreads.h
new file mode 100644
index 0000000000..2d32136379
--- /dev/null
+++ b/includes/rts/OSThreads.h
@@ -0,0 +1,209 @@
+/* ---------------------------------------------------------------------------
+ *
+ * (c) The GHC Team, 2001-2005
+ *
+ * Accessing OS threads functionality in a (mostly) OS-independent
+ * manner. 
+ * 
+ * --------------------------------------------------------------------------*/
+
+#ifndef RTS_OSTHREADS_H
+#define RTS_OSTHREADS_H
+
+#if defined(THREADED_RTS) /* to the end */
+
+# if defined(HAVE_PTHREAD_H) && !defined(WANT_NATIVE_WIN32_THREADS)
+
+#if CMINUSMINUS
+
+#define ACQUIRE_LOCK(mutex) foreign "C" pthread_mutex_lock(mutex)
+#define RELEASE_LOCK(mutex) foreign "C" pthread_mutex_unlock(mutex)
+#define ASSERT_LOCK_HELD(mutex) /* nothing */
+
+#else
+
+#include <pthread.h>
+#include <errno.h>
+
+typedef pthread_cond_t  Condition;
+typedef pthread_mutex_t Mutex;
+typedef pthread_t       OSThreadId;
+typedef pthread_key_t   ThreadLocalKey;
+
+#define OSThreadProcAttr /* nothing */
+
+#define INIT_COND_VAR       PTHREAD_COND_INITIALIZER
+
+#ifdef LOCK_DEBUG
+#define LOCK_DEBUG_BELCH(what, mutex) \
+  debugBelch("%s(0x%p) %s %d\n", what, mutex, __FILE__, __LINE__)
+#else
+#define LOCK_DEBUG_BELCH(what, mutex) /* nothing */
+#endif
+
+/* Always check the result of lock and unlock. */
+#define ACQUIRE_LOCK(mutex) \
+  LOCK_DEBUG_BELCH("ACQUIRE_LOCK", mutex); \
+  if (pthread_mutex_lock(mutex) == EDEADLK) { \
+    barf("multiple ACQUIRE_LOCK: %s %d", __FILE__,__LINE__); \
+  }
+
+#define RELEASE_LOCK(mutex) \
+  LOCK_DEBUG_BELCH("RELEASE_LOCK", mutex); \
+  if (pthread_mutex_unlock(mutex) != 0) { \
+    barf("RELEASE_LOCK: I do not own this lock: %s %d", __FILE__,__LINE__); \
+  }
+
+// Note: this assertion calls pthread_mutex_lock() on a mutex that
+// is already held by the calling thread.  The mutex should therefore
+// have been created with PTHREAD_MUTEX_ERRORCHECK, otherwise this
+// assertion will hang.  We always initialise mutexes with
+// PTHREAD_MUTEX_ERRORCHECK when DEBUG is on (see rts/posix/OSThreads.h).
+#define ASSERT_LOCK_HELD(mutex) ASSERT(pthread_mutex_lock(mutex) == EDEADLK)
+
+#endif // CMINUSMINUS
+
+# elif defined(HAVE_WINDOWS_H)
+
+#if CMINUSMINUS
+
+/* We jump through a hoop here to get a CCall EnterCriticalSection
+   and LeaveCriticalSection, as that's what C-- wants. */
+
+#define ACQUIRE_LOCK(mutex) foreign "stdcall" EnterCriticalSection(mutex)
+#define RELEASE_LOCK(mutex) foreign "stdcall" LeaveCriticalSection(mutex)
+#define ASSERT_LOCK_HELD(mutex) /* nothing */
+
+#else
+
+#include <windows.h>
+
+typedef HANDLE Condition;
+typedef DWORD OSThreadId;
+// don't be tempted to use HANDLE as the OSThreadId: there can be 
+// many HANDLES to a given thread, so comparison would not work.
+typedef DWORD ThreadLocalKey;
+
+#define OSThreadProcAttr __stdcall
+
+#define INIT_COND_VAR  0
+
+// We have a choice for implementing Mutexes on Windows.  Standard
+// Mutexes are kernel objects that require kernel calls to
+// acquire/release, whereas CriticalSections are spin-locks that block
+// in the kernel after spinning for a configurable number of times.
+// CriticalSections are *much* faster, so we use those.  The Mutex
+// implementation is left here for posterity.
+#define USE_CRITICAL_SECTIONS 1
+
+#if USE_CRITICAL_SECTIONS
+
+typedef CRITICAL_SECTION Mutex;
+
+#ifdef LOCK_DEBUG
+
+#define ACQUIRE_LOCK(mutex) \
+  debugBelch("ACQUIRE_LOCK(0x%p) %s %d\n", mutex,__FILE__,__LINE__); \
+  EnterCriticalSection(mutex)
+#define RELEASE_LOCK(mutex) \
+  debugBelch("RELEASE_LOCK(0x%p) %s %d\n", mutex,__FILE__,__LINE__); \
+  LeaveCriticalSection(mutex)
+#define ASSERT_LOCK_HELD(mutex) /* nothing */
+
+#else
+
+#define ACQUIRE_LOCK(mutex)  EnterCriticalSection(mutex)
+#define RELEASE_LOCK(mutex)  LeaveCriticalSection(mutex)
+
+// I don't know how to do this.  TryEnterCriticalSection() doesn't do
+// the right thing.
+#define ASSERT_LOCK_HELD(mutex) /* nothing */
+
+#endif
+
+#else
+
+typedef HANDLE Mutex;
+
+// casting to (Mutex *) here required due to use in .cmm files where
+// the argument has (void *) type.
+#define ACQUIRE_LOCK(mutex)					\
+    if (WaitForSingleObject(*((Mutex *)mutex),INFINITE) == WAIT_FAILED) { \
+	barf("WaitForSingleObject: %d", GetLastError());	\
+    }
+
+#define RELEASE_LOCK(mutex)				\
+    if (ReleaseMutex(*((Mutex *)mutex)) == 0) {		\
+	barf("ReleaseMutex: %d", GetLastError());	\
+    }
+
+#define ASSERT_LOCK_HELD(mutex) /* nothing */
+#endif
+
+#endif // CMINUSMINUS
+
+# else
+#  error "Threads not supported"
+# endif
+
+
+#ifndef CMINUSMINUS
+//
+// General thread operations
+//
+extern OSThreadId osThreadId      ( void );
+extern void shutdownThread        ( void )   GNUC3_ATTRIBUTE(__noreturn__);
+extern void yieldThread           ( void );
+
+typedef void OSThreadProcAttr OSThreadProc(void *);
+
+extern int  createOSThread        ( OSThreadId* tid, 
+				    OSThreadProc *startProc, void *param);
+extern rtsBool osThreadIsAlive    ( OSThreadId id );
+
+//
+// Condition Variables
+//
+extern void initCondition         ( Condition* pCond );
+extern void closeCondition        ( Condition* pCond );
+extern rtsBool broadcastCondition ( Condition* pCond );
+extern rtsBool signalCondition    ( Condition* pCond );
+extern rtsBool waitCondition      ( Condition* pCond, 
+				    Mutex* pMut );
+
+//
+// Mutexes
+//
+extern void initMutex             ( Mutex* pMut );
+extern void closeMutex            ( Mutex* pMut );
+
+//
+// Thread-local storage
+//
+void  newThreadLocalKey (ThreadLocalKey *key);
+void *getThreadLocalVar (ThreadLocalKey *key);
+void  setThreadLocalVar (ThreadLocalKey *key, void *value);
+void  freeThreadLocalKey (ThreadLocalKey *key);
+
+// Processors and affinity
+nat  getNumberOfProcessors (void);
+void setThreadAffinity     (nat n, nat m);
+#endif // !CMINUSMINUS
+
+#else
+
+#define ACQUIRE_LOCK(l)
+#define RELEASE_LOCK(l)
+#define ASSERT_LOCK_HELD(l)
+
+#endif /* defined(THREADED_RTS) */
+
+//
+// Support for forkOS (defined regardless of THREADED_RTS, but does
+// nothing when !THREADED_RTS).
+//
+#ifndef CMINUSMINUS
+int forkOS_createThread ( HsStablePtr entry );
+#endif
+
+#endif /* RTS_OSTHREADS_H */