/*

  * Copyright (c) 1997-1999

  * Silicon Graphics Computer Systems, Inc.

  *

  * Copyright (c) 1999 

  * Boris Fomitchev

  *

  * This material is provided "as is", with absolutely no warranty expressed

  * or implied. Any use is at your own risk.

  *

  * Permission to use or copy this software for any purpose is hereby granted 

  * without fee, provided the above notices are retained on all copies.

  * Permission to modify the code and to distribute modified code is granted,

  * provided the above notices are retained, and a notice that the code was

  * modified is included with the above copyright notice.

  *

  */

 // WARNING: This is an internal header file, included by other C++

 // standard library headers.  You should not attempt to use this header

 // file directly.

 // Stl_config.h should be included before this file.

 #ifndef _STLP_INTERNAL_THREADS_H

 #define _STLP_INTERNAL_THREADS_H

 // Supported threading models are native SGI, pthreads, uithreads

 // (similar to pthreads, but based on an earlier draft of the Posix

 // threads standard), and Win32 threads.  Uithread support by Jochen

 // Schlick, 1999, and Solaris threads generalized to them.

 #ifndef _STLP_CONFIG_H

 #include <stl/_config.h>

 #endif

 # if ! defined (_STLP_CSTDDEF)

 #  include <cstddef>

 # endif

 # if ! defined (_STLP_CSTDLIB)

 #  include <cstdlib>

 # endif

 // On SUN and Mac OS X gcc, zero-initialization works just fine...

 # if defined (__sun) || ( defined(__GNUC__) && defined(__APPLE__) )

 # define _STLP_MUTEX_INITIALIZER

 # endif

 # if defined (_STLP_WIN32) || defined (__sgi) || defined (_STLP_SPARC_SOLARIS_THREADS)

   typedef long __stl_atomic_t;

 # else 

 # if defined (_STLP_USE_NAMESPACES) && ! defined (_STLP_VENDOR_GLOBAL_CSTD)

 // using _STLP_VENDOR_CSTD::size_t;

 using namespace _STLP_VENDOR_CSTD;

 # endif

   typedef size_t __stl_atomic_t;

 #endif  

 # if defined(_STLP_SGI_THREADS)

 #  include <mutex.h>

 // Hack for SGI o32 compilers.

 #if !defined(__add_and_fetch) && \

     (__mips < 3 || !(defined (_ABIN32) || defined(_ABI64)))

 #  define __add_and_fetch(__l,__v) add_then_test((unsigned long*)__l,__v)  

 #  define __test_and_set(__l,__v)  test_and_set(__l,__v)

 #endif /* o32 */

 # if __mips < 3 || !(defined (_ABIN32) || defined(_ABI64))

 #  define _STLP_ATOMIC_EXCHANGE(__p, __q) test_and_set(__p, __q)

 # else

 #  define _STLP_ATOMIC_EXCHANGE(__p, __q) __test_and_set((unsigned long*)__p, (unsigned long)__q)

 # endif

 #  define _STLP_ATOMIC_INCREMENT(__x) __add_and_fetch(__x, 1)

 #  define _STLP_ATOMIC_DECREMENT(__x) __add_and_fetch(__x, (size_t) -1)

 # elif defined (__GNUC__) && defined (__i386__) && defined (__unix__) && defined (_STLP_USE_INLINE_X86_SPINLOCK) 

 // gcc on i386 linux, freebsd, etc. 

 // This enables the memory caching on x86 linux.  It is critical for SMP

 // without it the performace is DISMAL!

 static inline unsigned long __xchg(volatile __stl_atomic_t* target, int source)

 {

   // The target is refernce in memory rather than the register

   // because making a copy of it from memory to the register and

   // back again would ruin the atomic nature of the call.

   // the source does not need to be delt with atomicly so it can

   // be copied about as needed.

   //

   // The casting of the source is used to prevent gcc from optimizing 

   // in such a way that breaks the atomic nature of this call.

   //

   __asm__ __volatile__("xchgl %1,%0"

 		       :"=m" (*(volatile long *) target), "=r" (source)

 		       :"m" (*(volatile long *) target), "r" (source) );

   return source;

   //  The assembly above does the following atomicly:

   //   int temp=source;

   //   source=(int)(*target);

   //   (int)(*target)=temp;

   // return source

 }

 static inline void __inc_and_fetch(volatile __stl_atomic_t* __x)

 {

   // Referenced in memory rather than register to preserve the atomic nature.

   //

   __asm__ __volatile__(

       "lock; incl %0"

       :"=m" (*__x)

       :"m" (*__x) );

   //  The assembly above does the following atomicly:

   //   ++(int)(*__x);

 }

 static inline void __dec_and_fetch(volatile __stl_atomic_t* __x)

 {

   // Referenced in memory rather than register to preserve the atomic nature.

   //

   __asm__ __volatile__(

       "lock; decl %0"

       :"=m" (*__x)

       :"m" (*__x) );

   //  The assembly above does the following atomicly:

   //   --(int)(*__x);

 }

 #  define _STLP_ATOMIC_EXCHANGE(target, newValue) ((__xchg(target, newValue)))

 #  define _STLP_ATOMIC_INCREMENT(__x) __inc_and_fetch(__x)

 #  define _STLP_ATOMIC_DECREMENT(__x) __dec_and_fetch(__x)

 # elif defined(_STLP_PTHREADS)

 #  include <pthread.h>

 #  ifndef _STLP_USE_PTHREAD_SPINLOCK

 #   if defined(PTHREAD_MUTEX_INITIALIZER) && !defined(_STLP_MUTEX_INITIALIZER)

 #    define _STLP_MUTEX_INITIALIZER = { PTHREAD_MUTEX_INITIALIZER }

 #   endif

 //HPUX variants have (on some platforms optional) non-standard "DCE" pthreads impl

 #   if defined(_DECTHREADS_) && (defined(_PTHREAD_USE_D4) || defined(__hpux)) && !defined(_CMA_SUPPRESS_EXTERNALS_)

 #    define _STLP_PTHREAD_ATTR_DEFAULT pthread_mutexattr_default

 #   else

 #    define _STLP_PTHREAD_ATTR_DEFAULT 0

 #   endif

 #  endif // !_STLP_USE_PTHREAD_SPINLOCK 

 # elif defined(_STLP_WIN32THREADS)

 #  if !defined (_STLP_WINDOWS_H_INCLUDED) && ! defined (_WINDOWS_H)

 #   if ! (defined ( _STLP_MSVC ) || defined (__BORLANDC__) || defined (__ICL) || defined (__WATCOMC__) || defined (__MINGW32__) || defined (__DMC__))

 #    ifdef _STLP_USE_MFC

 #     include <afx.h>

 #    else

 #     include <windows.h>

 #    endif

 #    define _STLP_WINDOWS_H_INCLUDED

 #   else 

 // This section serves as a replacement for windows.h header for Visual C++

 extern "C" {

 #   if (defined(_M_MRX000) || defined(_M_ALPHA) \

        || (defined(_M_PPC) && (_MSC_VER >= 1000))) && !defined(RC_INVOKED)

 #    define InterlockedIncrement       _InterlockedIncrement

 #    define InterlockedDecrement       _InterlockedDecrement

 #    define InterlockedExchange        _InterlockedExchange

 #    define _STLP_STDCALL

 #   else

 #    ifdef _MAC

 #     define _STLP_STDCALL _cdecl

 #    else

 #     define _STLP_STDCALL __stdcall

 #    endif

 #   endif

 #if (_MSC_VER >= 1300) || defined (_STLP_NEW_PLATFORM_SDK)

 _STLP_IMPORT_DECLSPEC long _STLP_STDCALL InterlockedIncrement(long volatile *);

 _STLP_IMPORT_DECLSPEC long _STLP_STDCALL InterlockedDecrement(long volatile *);

 _STLP_IMPORT_DECLSPEC long _STLP_STDCALL InterlockedExchange(long volatile *, long);

 #else

   // boris : for the latest SDK, you may actually need the other version of the declaration (above)

   // even for earlier VC++ versions. There is no way to tell SDK versions apart, sorry ...

 _STLP_IMPORT_DECLSPEC long _STLP_STDCALL InterlockedIncrement(long*);

 _STLP_IMPORT_DECLSPEC long _STLP_STDCALL InterlockedDecrement(long*);

 _STLP_IMPORT_DECLSPEC long _STLP_STDCALL InterlockedExchange(long*, long);

 #endif

 _STLP_IMPORT_DECLSPEC void _STLP_STDCALL Sleep(unsigned long);

 _STLP_IMPORT_DECLSPEC void _STLP_STDCALL OutputDebugStringA( const char* lpOutputString );

 #ifdef _STLP_DEBUG

 typedef unsigned long DWORD;

 _STLP_IMPORT_DECLSPEC DWORD _STLP_STDCALL GetCurrentThreadId();

 #endif /* _STLP_DEBUG */

 #    if defined (InterlockedIncrement)

 #     pragma intrinsic(_InterlockedIncrement)

 #     pragma intrinsic(_InterlockedDecrement)

 #     pragma intrinsic(_InterlockedExchange)

 #    endif

 } /* extern "C" */

 #   endif /* STL_MSVC */

 #   define _STLP_WINDOWS_H_INCLUDED

 #  endif /* _STLP_WIN32 */

 #  ifndef _STLP_ATOMIC_INCREMENT

 #   define _STLP_ATOMIC_INCREMENT(__x)           InterlockedIncrement((long*)__x)

 #   define _STLP_ATOMIC_DECREMENT(__x)           InterlockedDecrement((long*)__x)

 #   define _STLP_ATOMIC_EXCHANGE(__x, __y)       InterlockedExchange((long*)__x, (long)__y)

 #  endif

 # elif defined(__DECC) || defined(__DECCXX)

 #  include <machine/builtins.h>

 #  define _STLP_ATOMIC_EXCHANGE __ATOMIC_EXCH_LONG

 #  define _STLP_ATOMIC_INCREMENT(__x) __ATOMIC_ADD_LONG(__x, 1)

 #  define _STLP_ATOMIC_DECREMENT(__x) __ATOMIC_ADD_LONG(__x, -1)

 # elif defined(_STLP_SPARC_SOLARIS_THREADS)

 #  include <stl/_sparc_atomic.h>

 # elif defined (_STLP_UITHREADS)

 // this inclusion is potential hazard to bring up all sorts

 // of old-style headers. Let's assume vendor already know how

 // to deal with that.

 #  include <ctime>

 # if defined (_STLP_USE_NAMESPACES) && ! defined (_STLP_VENDOR_GLOBAL_CSTD)

 using _STLP_VENDOR_CSTD::time_t;

 # endif

 #  include <synch.h>

 #  include <cstdio>

 #  include <stl/_cwchar.h>

 # elif defined (_STLP_BETHREADS)

 #  include <OS.h>

 #include <cassert>

 #include <stdio.h>

 #  define _STLP_MUTEX_INITIALIZER = { 0 }

 #elif defined(_STLP_OS2THREADS)

 # ifdef __GNUC__

 #  define INCL_DOSSEMAPHORES

 #  include <os2.h>

 # else

   // This section serves to replace os2.h for VisualAge C++

   typedef unsigned long ULONG;

   #ifndef __HEV__  /* INCL_SEMAPHORE may also define HEV */

     #define __HEV__

     typedef ULONG HEV;

     typedef HEV*  PHEV;

   #endif

   typedef ULONG APIRET;

   typedef ULONG HMTX;

   typedef HMTX*  PHMTX;

   typedef const char*  PCSZ;

   typedef ULONG BOOL32;

   APIRET _System DosCreateMutexSem(PCSZ pszName, PHEV phev, ULONG flAttr, BOOL32 fState);

   APIRET _System DosRequestMutexSem(HMTX hmtx, ULONG ulTimeout);

   APIRET _System DosReleaseMutexSem(HMTX hmtx);

   APIRET _System DosCloseMutexSem(HMTX hmtx);

 # define _STLP_MUTEX_INITIALIZER = { 0 };

 #  endif /* GNUC */

 # elif defined(_STLP_VXWORKS_THREADS)

 #  include "semLib.h"

 # endif

 # ifndef _STLP_MUTEX_INITIALIZER

 #   if defined(_STLP_ATOMIC_EXCHANGE)

 // we are using our own spinlock. 

 #     define _STLP_MUTEX_INITIALIZER = { 0 }

 #   elif defined(_STLP_UITHREADS)

 // known case

 #     define _STLP_MUTEX_INITIALIZER = { DEFAULTMUTEX }

 #   else

 // we do not have static initializer available. therefore, on-demand synchronization is needed.

 #     define _STLP_MUTEX_INITIALIZER

 #     define _STLP_MUTEX_NEEDS_ONDEMAND_INITIALIZATION

 #   endif

 # endif

 _STLP_BEGIN_NAMESPACE

 #ifndef _STLP_USE_PTHREAD_SPINLOCK

 // Helper struct.  This is a workaround for various compilers that don't

 // handle static variables in inline functions properly.

 template <int __inst>

 struct _STLP_mutex_spin {

   enum { __low_max = 30, __high_max = 1000 };

   // Low if we suspect uniprocessor, high for multiprocessor.

   static unsigned __max;

   static unsigned __last;

   static void _STLP_CALL _M_do_lock(volatile __stl_atomic_t* __lock);

   static void _STLP_CALL _S_nsec_sleep(int __log_nsec);

 };

 #endif // !_STLP_USE_PTHREAD_SPINLOCK

 // Locking class.  Note that this class *does not have a constructor*.

 // It must be initialized either statically, with _STLP_MUTEX_INITIALIZER,

 // or dynamically, by explicitly calling the _M_initialize member function.

 // (This is similar to the ways that a pthreads mutex can be initialized.)

 // There are explicit member functions for acquiring and releasing the lock.

 // There is no constructor because static initialization is essential for

 // some uses, and only a class aggregate (see section 8.5.1 of the C++

 // standard) can be initialized that way.  That means we must have no

 // constructors, no base classes, no virtual functions, and no private or

 // protected members.

 // For non-static cases, clients should use  _STLP_mutex.

 struct _STLP_CLASS_DECLSPEC _STLP_mutex_base

 {

 #if defined(_STLP_ATOMIC_EXCHANGE) || defined(_STLP_SGI_THREADS)

   // It should be relatively easy to get this to work on any modern Unix.

   volatile __stl_atomic_t _M_lock;

 #endif

 #ifdef _STLP_THREADS

 # ifdef _STLP_ATOMIC_EXCHANGE

   inline void _M_initialize() { _M_lock=0; }

   inline void _M_destroy() {}

   void _M_acquire_lock() {

     _STLP_mutex_spin<0>::_M_do_lock(&_M_lock);

   }

   inline void _M_release_lock() {

     volatile __stl_atomic_t* __lock = &_M_lock;

 #  if defined(_STLP_SGI_THREADS) && defined(__GNUC__) && __mips >= 3

         asm("sync");

         *__lock = 0;

 #  elif defined(_STLP_SGI_THREADS) && __mips >= 3 \

 	 && (defined (_ABIN32) || defined(_ABI64))

         __lock_release(__lock);

 #  elif defined (_STLP_SPARC_SOLARIS_THREADS)

 #   if defined (__WORD64) || defined (__arch64__) || defined (__sparcv9) || defined (__sparcv8plus)

 	asm("membar #StoreStore ; membar #LoadStore");

 #   else

 	asm(" stbar ");

 #   endif

         *__lock = 0;	

 #  else

         *__lock = 0;

         // This is not sufficient on many multiprocessors, since

         // writes to protected variables and the lock may be reordered.

 #  endif

   }

 # elif defined(_STLP_PTHREADS)

 #  ifdef _STLP_USE_PTHREAD_SPINLOCK

   pthread_spinlock_t _M_lock;

   inline void _M_initialize() { pthread_spin_init( &_M_lock, 0 ); }

   inline void _M_destroy() { pthread_spin_destroy( &_M_lock ); }

   inline void _M_acquire_lock() { 

     // we do not care about race conditions here : there is only one thread at this point 

     if(!_M_lock) pthread_spin_init( &_M_lock, 0 );

     // fbp: here, initialization on demand should happen before the lock

     // we use simple strategy as we are sure this only happens on initialization

     pthread_spin_lock( &_M_lock );

   }

   inline void _M_acquire_lock_nodemand() { 

     pthread_spin_lock( &_M_lock ); 

   }

   inline void _M_release_lock() { pthread_spin_unlock( &_M_lock ); }

 #  else // !_STLP_USE_PTHREAD_SPINLOCK

   pthread_mutex_t _M_lock;

   inline void _M_initialize() {

     pthread_mutex_init(&_M_lock,_STLP_PTHREAD_ATTR_DEFAULT);

   }

   inline void _M_destroy() {

     pthread_mutex_destroy(&_M_lock);

   }

   inline void _M_acquire_lock_nodemand() { 

     pthread_mutex_lock(&_M_lock);

   }

   inline void _M_acquire_lock() { 

 #    if defined (__hpux) && !defined (PTHREAD_MUTEX_INITIALIZER)

       if (!_M_lock.field1)  _M_initialize();

 #    endif

      pthread_mutex_lock(&_M_lock);

   }

   inline void _M_release_lock() { pthread_mutex_unlock(&_M_lock); }

 #  endif // !_STLP_USE_PTHREAD_SPINLOCK

 # elif defined (_STLP_UITHREADS)

   mutex_t _M_lock;

   inline void _M_initialize() {

     mutex_init(&_M_lock,0,NULL);	

   }

   inline void _M_destroy() {

     mutex_destroy(&_M_lock);

   }

   inline void _M_acquire_lock() { mutex_lock(&_M_lock); }

   inline void _M_release_lock() { mutex_unlock(&_M_lock); }

 # elif defined(_STLP_OS2THREADS)

   HMTX _M_lock;

   inline void _M_initialize() { DosCreateMutexSem(NULL, &_M_lock, 0, false); }

   inline void _M_destroy() { DosCloseMutexSem(_M_lock); }

   inline void _M_acquire_lock_nodemand() {

     DosRequestMutexSem(_M_lock, SEM_INDEFINITE_WAIT);

   }  

   inline void _M_acquire_lock() {

     if(!_M_lock) _M_initialize();

     DosRequestMutexSem(_M_lock, SEM_INDEFINITE_WAIT);

   }

   inline void _M_release_lock() { DosReleaseMutexSem(_M_lock); }

 # elif defined(_STLP_BETHREADS)

   sem_id sem;

   inline void _M_initialize() 

   {

      sem = create_sem(1, "STLPort");

      assert(sem > 0);

   }

   inline void _M_destroy() 

   {

      int t = delete_sem(sem);

      assert(t == B_NO_ERROR);

   }

   inline void _M_acquire_lock_nodemand()

   {

     status_t t;

     t = acquire_sem(sem);

     assert(t == B_NO_ERROR);

   }

   inline void _M_acquire_lock();

   inline void _M_release_lock() 

   {

      status_t t = release_sem(sem);

      assert(t == B_NO_ERROR);

   }

 # elif defined(_STLP_VXWORKS_THREADS)

   SEM_ID _M_sem;

   inline void _M_initialize() 

   {

      _M_sem = semMCreate(SEM_Q_FIFO);

      assert(_M_sem > 0);

   }

   inline void _M_destroy() 

   {

     STATUS __s;

     semDelete (_M_sem);

     assert(__s == OK);

   }

   inline void _M_acquire_lock_nodemand()

   {

     STATUS __s;

     semTake (_M_sem, WAIT_FOREVER);

     assert(__s == OK);

   }

   inline void _M_acquire_lock()

   {

     if (!_M_sem)

       _M_initialize();

     _M_acquire_lock_nodemand();

   }

   inline void _M_release_lock() 

   {

     STATUS __s;

     semGive (_M_sem, WAIT_FOREVER);

     assert(__s == OK);

   }

 # else		//*ty 11/24/2001 - added configuration check

 #  error "Unknown thread facility configuration"

 # endif

 #else /* No threads */

   inline void _M_initialize() {}

   inline void _M_destroy() {}

   inline void _M_acquire_lock() {}

   inline void _M_release_lock() {}

 #endif // _STLP_PTHREADS

 };

 #if defined (_STLP_THREADS) && defined (_STLP_MUTEX_NEEDS_ONDEMAND_INITIALIZATION)

 // for use in _STLP_mutex, our purposes do not require ondemand initialization

 // also, mutex_base may use some hacks to determine uninitialized state by zero data, which only works for globals.

 class _STLP_CLASS_DECLSPEC _STLP_mutex_nodemand : public _STLP_mutex_base {

   inline void _M_acquire_lock() { 

     _M_acquire_lock_nodemand();

   }

 };

 #else

 typedef _STLP_mutex_base _STLP_mutex_nodemand;

 #endif

 // Locking class.  The constructor initializes the lock, the destructor destroys it.

 // Well - behaving class, does not need static initializer

 class _STLP_CLASS_DECLSPEC _STLP_mutex : public _STLP_mutex_nodemand {

   public:

     inline _STLP_mutex () { _M_initialize(); }

     inline ~_STLP_mutex () { _M_destroy(); }

   private:

     _STLP_mutex(const _STLP_mutex&);

     void operator=(const _STLP_mutex&);

 };

 /*

  * Class _Refcount_Base provides a type, __stl_atomic_t, a data member,

  * _M_ref_count, and member functions _M_incr and _M_decr, which perform

  * atomic preincrement/predecrement.  The constructor initializes 

  * _M_ref_count.

  */

 struct _STLP_CLASS_DECLSPEC _Refcount_Base

 {

   // The data member _M_ref_count

   volatile __stl_atomic_t _M_ref_count;

 # if !defined (_STLP_ATOMIC_EXCHANGE)

   _STLP_mutex _M_mutex;

 # endif

   // Constructor

   _Refcount_Base(__stl_atomic_t __n) : _M_ref_count(__n) {}

   // _M_incr and _M_decr

 # if defined (_STLP_THREADS) && defined (_STLP_ATOMIC_EXCHANGE)

    void _M_incr() { _STLP_ATOMIC_INCREMENT((__stl_atomic_t*)&_M_ref_count); }

    void _M_decr() { _STLP_ATOMIC_DECREMENT((__stl_atomic_t*)&_M_ref_count); }

 # elif defined(_STLP_THREADS)

   void _M_incr() {

     _M_mutex._M_acquire_lock();

     ++_M_ref_count;

     _M_mutex._M_release_lock();

   }

   void _M_decr() {

     _M_mutex._M_acquire_lock();

     --_M_ref_count;

     _M_mutex._M_release_lock();

   }

 # else  /* No threads */

   void _M_incr() { ++_M_ref_count; }

   void _M_decr() { --_M_ref_count; }

 # endif

 };

 // Atomic swap on unsigned long

 // This is guaranteed to behave as though it were atomic only if all

 // possibly concurrent updates use _Atomic_swap.

 // In some cases the operation is emulated with a lock.

 # if defined (_STLP_THREADS)

 #  ifdef _STLP_ATOMIC_EXCHANGE

 inline __stl_atomic_t _Atomic_swap(volatile __stl_atomic_t * __p, __stl_atomic_t __q) {

   return (__stl_atomic_t) _STLP_ATOMIC_EXCHANGE(__p,__q);

 }

 #  elif defined(_STLP_PTHREADS) || defined (_STLP_UITHREADS) || defined (_STLP_OS2THREADS) || defined(_STLP_USE_PTHREAD_SPINLOCK)

 // We use a template here only to get a unique initialized instance.

 template<int __dummy>

 struct _Swap_lock_struct {

   static _STLP_STATIC_MUTEX _S_swap_lock;

 };

 // This should be portable, but performance is expected

 // to be quite awful.  This really needs platform specific

 // code.

 inline __stl_atomic_t _Atomic_swap(volatile __stl_atomic_t * __p, __stl_atomic_t __q) {

   _Swap_lock_struct<0>::_S_swap_lock._M_acquire_lock();

   __stl_atomic_t __result = *__p;

   *__p = __q;

   _Swap_lock_struct<0>::_S_swap_lock._M_release_lock();

   return __result;

 }

 #  endif // _STLP_PTHREADS || _STLP_UITHREADS || _STLP_OS2THREADS || _STLP_USE_PTHREAD_SPINLOCK

 # else // !_STLP_THREADS

 /* no threads */

 static inline __stl_atomic_t  _STLP_CALL

 _Atomic_swap(volatile __stl_atomic_t * __p, __stl_atomic_t __q) {

   __stl_atomic_t __result = *__p;

   *__p = __q;

   return __result;

 }

 # endif // _STLP_THREADS

 // A locking class that uses _STLP_STATIC_MUTEX.  The constructor takes

 // a reference to an _STLP_STATIC_MUTEX, and acquires a lock.  The destructor

 // releases the lock.

 struct _STLP_CLASS_DECLSPEC _STLP_auto_lock

 {

   _STLP_STATIC_MUTEX& _M_lock;

   _STLP_auto_lock(_STLP_STATIC_MUTEX& __lock) : _M_lock(__lock)

     { _M_lock._M_acquire_lock(); }

   ~_STLP_auto_lock() { _M_lock._M_release_lock(); }

 private:

   void operator=(const _STLP_auto_lock&);

   _STLP_auto_lock(const _STLP_auto_lock&);

 };

 typedef _STLP_auto_lock _STLP_mutex_lock;

 #ifdef _STLP_BETHREADS

 template <int __inst>

 struct _STLP_beos_static_lock_data

 {

 	static bool is_init;

 	struct mutex_t : public _STLP_mutex

 	{

 		mutex_t()

 		{

 			_STLP_beos_static_lock_data<0>::is_init = true;

 		}

 		~mutex_t()

 		{

 			_STLP_beos_static_lock_data<0>::is_init = false;

 		}

 	};

 	static mutex_t mut;

 };

 template <int __inst>

 bool _STLP_beos_static_lock_data<__inst>::is_init = false;

 template <int __inst>

 typename _STLP_beos_static_lock_data<__inst>::mutex_t _STLP_beos_static_lock_data<__inst>::mut;

 inline void _STLP_mutex_base::_M_acquire_lock() 

 {

 	if(sem == 0)

 	{

 		// we need to initialise on demand here

 		// to prevent race conditions use our global

 		// mutex if it's available:

 		if(_STLP_beos_static_lock_data<0>::is_init)

 		{

 			_STLP_auto_lock al(_STLP_beos_static_lock_data<0>::mut);

 			if(sem == 0) _M_initialize();

 		}

 		else

 		{

 			// no lock available, we must still be

 			// in startup code, THERE MUST BE ONE THREAD

 			// ONLY active at this point.

 			_M_initialize();

 		}

 	}

 	_M_acquire_lock_nodemand();

 }

 #endif

 _STLP_END_NAMESPACE

 # if !defined (_STLP_LINK_TIME_INSTANTIATION)

 #  include <stl/_threads.c>

 # endif

 #endif /* _STLP_INTERNAL_THREADS_H */

 // Local Variables:

 // mode:C++

 // End: