URL https://opencores.org/ocsvn/openrisc/openrisc/trunk

Subversion Repositories openrisc

[/] [openrisc/] [trunk/] [gnu-old/] [gcc-4.2.2/] [gcc/] [gthr-win32.h] - Blame information for rev 867

Go to most recent revision | Details | Compare with Previous | View Log


/* Threads compatibility routines for libgcc2 and libobjc.  */
/* Compile this one with gcc.  */
 
/* Copyright (C) 1999, 2000, 2002, 2003, 2004, 2005
   Free Software Foundation, Inc.
   Contributed by Mumit Khan <khan@xraylith.wisc.edu>.
 
This file is part of GCC.
 
GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 2, or (at your option) any later
version.
 
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
for more details.
 
You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING.  If not, write to the Free
Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301, USA.  */
 
/* As a special exception, if you link this library with other files,
   some of which are compiled with GCC, to produce an executable,
   this library does not by itself cause the resulting executable
   to be covered by the GNU General Public License.
   This exception does not however invalidate any other reasons why
   the executable file might be covered by the GNU General Public License.  */
 
#ifndef GCC_GTHR_WIN32_H
#define GCC_GTHR_WIN32_H
 
/* Windows32 threads specific definitions. The windows32 threading model
   does not map well into pthread-inspired gcc's threading model, and so
   there are caveats one needs to be aware of.
 
   1. The destructor supplied to __gthread_key_create is ignored for
      generic x86-win32 ports. This will certainly cause memory leaks
      due to unreclaimed eh contexts (sizeof (eh_context) is at least
      24 bytes for x86 currently).
 
      This memory leak may be significant for long-running applications
      that make heavy use of C++ EH.
 
      However, Mingw runtime (version 0.3 or newer) provides a mechanism
      to emulate pthreads key dtors; the runtime provides a special DLL,
      linked in if -mthreads option is specified, that runs the dtors in
      the reverse order of registration when each thread exits. If
      -mthreads option is not given, a stub is linked in instead of the
      DLL, which results in memory leak. Other x86-win32 ports can use
      the same technique of course to avoid the leak.
 
   2. The error codes returned are non-POSIX like, and cast into ints.
      This may cause incorrect error return due to truncation values on
      hw where sizeof (DWORD) > sizeof (int).
 
   3. We are currently using a special mutex instead of the Critical
      Sections, since Win9x does not support TryEnterCriticalSection
      (while NT does).
 
   The basic framework should work well enough. In the long term, GCC
   needs to use Structured Exception Handling on Windows32.  */
 
#define __GTHREADS 1
 
#include <errno.h>
#ifdef __MINGW32__
#include <_mingw.h>
#endif
 
#ifdef _LIBOBJC
 
/* This is necessary to prevent windef.h (included from windows.h) from
   defining its own BOOL as a typedef.  */
#ifndef __OBJC__
#define __OBJC__
#endif
#include <windows.h>
/* Now undef the windows BOOL.  */
#undef BOOL
 
/* Key structure for maintaining thread specific storage */
static DWORD    __gthread_objc_data_tls = (DWORD) -1;
 
/* Backend initialization functions */
 
/* Initialize the threads subsystem.  */
int
__gthread_objc_init_thread_system (void)
{
  /* Initialize the thread storage key.  */
  if ((__gthread_objc_data_tls = TlsAlloc ()) != (DWORD) -1)
    return 0;
  else
    return -1;
}
 
/* Close the threads subsystem.  */
int
__gthread_objc_close_thread_system (void)
{
  if (__gthread_objc_data_tls != (DWORD) -1)
    TlsFree (__gthread_objc_data_tls);
  return 0;
}
 
/* Backend thread functions */
 
/* Create a new thread of execution.  */
objc_thread_t
__gthread_objc_thread_detach (void (*func)(void *arg), void *arg)
{
  DWORD thread_id = 0;
  HANDLE win32_handle;
 
  if (!(win32_handle = CreateThread (NULL, 0, (LPTHREAD_START_ROUTINE) func,
                                     arg, 0, &thread_id)))
    thread_id = 0;
 
  return (objc_thread_t) thread_id;
}
 
/* Set the current thread's priority.  */
int
__gthread_objc_thread_set_priority (int priority)
{
  int sys_priority = 0;
 
  switch (priority)
    {
    case OBJC_THREAD_INTERACTIVE_PRIORITY:
      sys_priority = THREAD_PRIORITY_NORMAL;
      break;
    default:
    case OBJC_THREAD_BACKGROUND_PRIORITY:
      sys_priority = THREAD_PRIORITY_BELOW_NORMAL;
      break;
    case OBJC_THREAD_LOW_PRIORITY:
      sys_priority = THREAD_PRIORITY_LOWEST;
      break;
    }
 
  /* Change priority */
  if (SetThreadPriority (GetCurrentThread (), sys_priority))
    return 0;
  else
    return -1;
}
 
/* Return the current thread's priority.  */
int
__gthread_objc_thread_get_priority (void)
{
  int sys_priority;
 
  sys_priority = GetThreadPriority (GetCurrentThread ());
 
  switch (sys_priority)
    {
    case THREAD_PRIORITY_HIGHEST:
    case THREAD_PRIORITY_TIME_CRITICAL:
    case THREAD_PRIORITY_ABOVE_NORMAL:
    case THREAD_PRIORITY_NORMAL:
      return OBJC_THREAD_INTERACTIVE_PRIORITY;
 
    default:
    case THREAD_PRIORITY_BELOW_NORMAL:
      return OBJC_THREAD_BACKGROUND_PRIORITY;
 
    case THREAD_PRIORITY_IDLE:
    case THREAD_PRIORITY_LOWEST:
      return OBJC_THREAD_LOW_PRIORITY;
    }
 
  /* Couldn't get priority.  */
  return -1;
}
 
/* Yield our process time to another thread.  */
void
__gthread_objc_thread_yield (void)
{
  Sleep (0);
}
 
/* Terminate the current thread.  */
int
__gthread_objc_thread_exit (void)
{
  /* exit the thread */
  ExitThread (__objc_thread_exit_status);
 
  /* Failed if we reached here */
  return -1;
}
 
/* Returns an integer value which uniquely describes a thread.  */
objc_thread_t
__gthread_objc_thread_id (void)
{
  return (objc_thread_t) GetCurrentThreadId ();
}
 
/* Sets the thread's local storage pointer.  */
int
__gthread_objc_thread_set_data (void *value)
{
  if (TlsSetValue (__gthread_objc_data_tls, value))
    return 0;
  else
    return -1;
}
 
/* Returns the thread's local storage pointer.  */
void *
__gthread_objc_thread_get_data (void)
{
  DWORD lasterror;
  void *ptr;
 
  lasterror = GetLastError ();
 
  ptr = TlsGetValue (__gthread_objc_data_tls);          /* Return thread data.  */
 
  SetLastError (lasterror);
 
  return ptr;
}
 
/* Backend mutex functions */
 
/* Allocate a mutex.  */
int
__gthread_objc_mutex_allocate (objc_mutex_t mutex)
{
  if ((mutex->backend = (void *) CreateMutex (NULL, 0, NULL)) == NULL)
    return -1;
  else
    return 0;
}
 
/* Deallocate a mutex.  */
int
__gthread_objc_mutex_deallocate (objc_mutex_t mutex)
{
  CloseHandle ((HANDLE) (mutex->backend));
  return 0;
}
 
/* Grab a lock on a mutex.  */
int
__gthread_objc_mutex_lock (objc_mutex_t mutex)
{
  int status;
 
  status = WaitForSingleObject ((HANDLE) (mutex->backend), INFINITE);
  if (status != WAIT_OBJECT_0 && status != WAIT_ABANDONED)
    return -1;
  else
    return 0;
}
 
/* Try to grab a lock on a mutex.  */
int
__gthread_objc_mutex_trylock (objc_mutex_t mutex)
{
  int status;
 
  status = WaitForSingleObject ((HANDLE) (mutex->backend), 0);
  if (status != WAIT_OBJECT_0 && status != WAIT_ABANDONED)
    return -1;
  else
    return 0;
}
 
/* Unlock the mutex */
int
__gthread_objc_mutex_unlock (objc_mutex_t mutex)
{
  if (ReleaseMutex ((HANDLE) (mutex->backend)) == 0)
    return -1;
  else
    return 0;
}
 
/* Backend condition mutex functions */
 
/* Allocate a condition.  */
int
__gthread_objc_condition_allocate (objc_condition_t condition)
{
  /* Unimplemented.  */
  return -1;
}
 
/* Deallocate a condition.  */
int
__gthread_objc_condition_deallocate (objc_condition_t condition)
{
  /* Unimplemented.  */
  return -1;
}
 
/* Wait on the condition */
int
__gthread_objc_condition_wait (objc_condition_t condition, objc_mutex_t mutex)
{
  /* Unimplemented.  */
  return -1;
}
 
/* Wake up all threads waiting on this condition.  */
int
__gthread_objc_condition_broadcast (objc_condition_t condition)
{
  /* Unimplemented.  */
  return -1;
}
 
/* Wake up one thread waiting on this condition.  */
int
__gthread_objc_condition_signal (objc_condition_t condition)
{
  /* Unimplemented.  */
  return -1;
}
 
#else /* _LIBOBJC */
 
#ifdef __cplusplus
extern "C" {
#endif
 
typedef unsigned long __gthread_key_t;
 
typedef struct {
  int done;
  long started;
} __gthread_once_t;
 
typedef struct {
  long counter;
  void *sema;
} __gthread_mutex_t;
 
typedef struct {
  long counter;
  long depth;
  unsigned long owner;
  void *sema;
} __gthread_recursive_mutex_t;
 
#define __GTHREAD_ONCE_INIT {0, -1}
#define __GTHREAD_MUTEX_INIT_FUNCTION __gthread_mutex_init_function
#define __GTHREAD_MUTEX_INIT_DEFAULT {-1, 0}
#define __GTHREAD_RECURSIVE_MUTEX_INIT_FUNCTION \
  __gthread_recursive_mutex_init_function
#define __GTHREAD_RECURSIVE_MUTEX_INIT_DEFAULT {-1, 0, 0, 0}
 
#if __MINGW32_MAJOR_VERSION >= 1 || \
  (__MINGW32_MAJOR_VERSION == 0 && __MINGW32_MINOR_VERSION > 2)
#define MINGW32_SUPPORTS_MT_EH 1
/* Mingw runtime >= v0.3 provides a magic variable that is set to nonzero
   if -mthreads option was specified, or 0 otherwise. This is to get around
   the lack of weak symbols in PE-COFF.  */
extern int _CRT_MT;
extern int __mingwthr_key_dtor (unsigned long, void (*) (void *));
#endif /* __MINGW32__ version */
 
/* The Windows95 kernel does not export InterlockedCompareExchange.
   This provides a substitute.   When building apps that reference
   gthread_mutex_try_lock, the  __GTHREAD_I486_INLINE_LOCK_PRIMITIVES
   macro  must be defined if Windows95 is a target.  Currently
   gthread_mutex_try_lock is not referenced by libgcc or libstdc++.  */
#ifdef __GTHREAD_I486_INLINE_LOCK_PRIMITIVES
static inline long
__gthr_i486_lock_cmp_xchg(long *dest, long xchg, long comperand)
{
  long result;
  __asm__ __volatile__ ("\n\
        lock\n\
        cmpxchg{l} {%4, %1|%1, %4}\n"
        : "=a" (result), "=m" (*dest)
        : "0" (comperand), "m" (*dest), "r" (xchg)
        : "cc");
  return result;
}
#define __GTHR_W32_InterlockedCompareExchange __gthr_i486_lock_cmp_xchg
#else  /* __GTHREAD_I486_INLINE_LOCK_PRIMITIVES */
#define __GTHR_W32_InterlockedCompareExchange InterlockedCompareExchange
#endif /* __GTHREAD_I486_INLINE_LOCK_PRIMITIVES */
 
static inline int
__gthread_active_p (void)
{
#ifdef MINGW32_SUPPORTS_MT_EH
  return _CRT_MT;
#else
  return 1;
#endif
}
 
#if __GTHREAD_HIDE_WIN32API
 
/* The implementations are in config/i386/gthr-win32.c in libgcc.a.
   Only stubs are exposed to avoid polluting the C++ namespace with
   windows api definitions.  */
 
extern int __gthr_win32_once (__gthread_once_t *, void (*) (void));
extern int __gthr_win32_key_create (__gthread_key_t *, void (*) (void*));
extern int __gthr_win32_key_delete (__gthread_key_t);
extern void * __gthr_win32_getspecific (__gthread_key_t);
extern int __gthr_win32_setspecific (__gthread_key_t, const void *);
extern void __gthr_win32_mutex_init_function (__gthread_mutex_t *);
extern int __gthr_win32_mutex_lock (__gthread_mutex_t *);
extern int __gthr_win32_mutex_trylock (__gthread_mutex_t *);
extern int __gthr_win32_mutex_unlock (__gthread_mutex_t *);
extern void
  __gthr_win32_recursive_mutex_init_function (__gthread_recursive_mutex_t *);
extern int __gthr_win32_recursive_mutex_lock (__gthread_recursive_mutex_t *);
extern int
  __gthr_win32_recursive_mutex_trylock (__gthread_recursive_mutex_t *);
extern int __gthr_win32_recursive_mutex_unlock (__gthread_recursive_mutex_t *);
 
static inline int
__gthread_once (__gthread_once_t *once, void (*func) (void))
{
  if (__gthread_active_p ())
    return __gthr_win32_once (once, func);
  else
    return -1;
}
 
static inline int
__gthread_key_create (__gthread_key_t *key, void (*dtor) (void *))
{
  return __gthr_win32_key_create (key, dtor);
}
 
static inline int
__gthread_key_delete (__gthread_key_t key)
{
  return __gthr_win32_key_delete (key);
}
 
static inline void *
__gthread_getspecific (__gthread_key_t key)
{
  return __gthr_win32_getspecific (key);
}
 
static inline int
__gthread_setspecific (__gthread_key_t key, const void *ptr)
{
  return __gthr_win32_setspecific (key, ptr);
}
 
static inline void
__gthread_mutex_init_function (__gthread_mutex_t *mutex)
{
  __gthr_win32_mutex_init_function (mutex);
}
 
static inline int
__gthread_mutex_lock (__gthread_mutex_t *mutex)
{
  if (__gthread_active_p ())
    return __gthr_win32_mutex_lock (mutex);
  else
    return 0;
}
 
static inline int
__gthread_mutex_trylock (__gthread_mutex_t *mutex)
{
  if (__gthread_active_p ())
    return __gthr_win32_mutex_trylock (mutex);
  else
    return 0;
}
 
static inline int
__gthread_mutex_unlock (__gthread_mutex_t *mutex)
{
  if (__gthread_active_p ())
    return __gthr_win32_mutex_unlock (mutex);
  else
    return 0;
}
 
static inline void
__gthread_recursive_mutex_init_function (__gthread_recursive_mutex_t *mutex)
{
   __gthr_win32_recursive_mutex_init_function (mutex);
}
 
static inline int
__gthread_recursive_mutex_lock (__gthread_recursive_mutex_t *mutex)
{
  if (__gthread_active_p ())
    return __gthr_win32_recursive_mutex_lock (mutex);
  else
    return 0;
}
 
static inline int
__gthread_recursive_mutex_trylock (__gthread_recursive_mutex_t *mutex)
{
  if (__gthread_active_p ())
    return __gthr_win32_recursive_mutex_trylock (mutex);
  else
    return 0;
}
 
static inline int
__gthread_recursive_mutex_unlock (__gthread_recursive_mutex_t *mutex)
{
  if (__gthread_active_p ())
    return __gthr_win32_recursive_mutex_unlock (mutex);
  else
    return 0;
}
 
#else /* ! __GTHREAD_HIDE_WIN32API */
 
#include <windows.h>
#include <errno.h>
 
static inline int
__gthread_once (__gthread_once_t *once, void (*func) (void))
{
  if (! __gthread_active_p ())
    return -1;
  else if (once == NULL || func == NULL)
    return EINVAL;
 
  if (! once->done)
    {
      if (InterlockedIncrement (&(once->started)) == 0)
        {
          (*func) ();
          once->done = TRUE;
        }
      else
        {
          /* Another thread is currently executing the code, so wait for it
             to finish; yield the CPU in the meantime.  If performance
             does become an issue, the solution is to use an Event that
             we wait on here (and set above), but that implies a place to
             create the event before this routine is called.  */
          while (! once->done)
            Sleep (0);
        }
    }
 
  return 0;
}
 
/* Windows32 thread local keys don't support destructors; this leads to
   leaks, especially in threaded applications making extensive use of
   C++ EH. Mingw uses a thread-support DLL to work-around this problem.  */
static inline int
__gthread_key_create (__gthread_key_t *key, void (*dtor) (void *))
{
  int status = 0;
  DWORD tls_index = TlsAlloc ();
  if (tls_index != 0xFFFFFFFF)
    {
      *key = tls_index;
#ifdef MINGW32_SUPPORTS_MT_EH
      /* Mingw runtime will run the dtors in reverse order for each thread
         when the thread exits.  */
      status = __mingwthr_key_dtor (*key, dtor);
#endif
    }
  else
    status = (int) GetLastError ();
  return status;
}
 
static inline int
__gthread_key_delete (__gthread_key_t key)
{
  return (TlsFree (key) != 0) ? 0 : (int) GetLastError ();
}
 
static inline void *
__gthread_getspecific (__gthread_key_t key)
{
  DWORD lasterror;
  void *ptr;
 
  lasterror = GetLastError ();
 
  ptr = TlsGetValue (key);
 
  SetLastError (lasterror);
 
  return ptr;
}
 
static inline int
__gthread_setspecific (__gthread_key_t key, const void *ptr)
{
  return (TlsSetValue (key, (void*) ptr) != 0) ? 0 : (int) GetLastError ();
}
 
static inline void
__gthread_mutex_init_function (__gthread_mutex_t *mutex)
{
  mutex->counter = -1;
  mutex->sema = CreateSemaphore (NULL, 0, 65535, NULL);
}
 
static inline int
__gthread_mutex_lock (__gthread_mutex_t *mutex)
{
  int status = 0;
 
  if (__gthread_active_p ())
    {
      if (InterlockedIncrement (&mutex->counter) == 0 ||
          WaitForSingleObject (mutex->sema, INFINITE) == WAIT_OBJECT_0)
        status = 0;
      else
        {
          /* WaitForSingleObject returns WAIT_FAILED, and we can only do
             some best-effort cleanup here.  */
          InterlockedDecrement (&mutex->counter);
          status = 1;
        }
    }
  return status;
}
 
static inline int
__gthread_mutex_trylock (__gthread_mutex_t *mutex)
{
  int status = 0;
 
  if (__gthread_active_p ())
    {
      if (__GTHR_W32_InterlockedCompareExchange (&mutex->counter, 0, -1) < 0)
        status = 0;
      else
        status = 1;
    }
  return status;
}
 
static inline int
__gthread_mutex_unlock (__gthread_mutex_t *mutex)
{
  if (__gthread_active_p ())
    {
      if (InterlockedDecrement (&mutex->counter) >= 0)
        return ReleaseSemaphore (mutex->sema, 1, NULL) ? 0 : 1;
    }
  return 0;
}
 
static inline void
__gthread_recursive_mutex_init_function (__gthread_recursive_mutex_t *mutex)
{
  mutex->counter = -1;
  mutex->depth = 0;
  mutex->owner = 0;
  mutex->sema = CreateSemaphore (NULL, 0, 65535, NULL);
}
 
static inline int
__gthread_recursive_mutex_lock (__gthread_recursive_mutex_t *mutex)
{
  if (__gthread_active_p ())
    {
      DWORD me = GetCurrentThreadId();
      if (InterlockedIncrement (&mutex->counter) == 0)
        {
          mutex->depth = 1;
          mutex->owner = me;
        }
      else if (mutex->owner == me)
        {
          InterlockedDecrement (&mutex->counter);
          ++(mutex->depth);
        }
      else if (WaitForSingleObject (mutex->sema, INFINITE) == WAIT_OBJECT_0)
        {
          mutex->depth = 1;
          mutex->owner = me;
        }
      else
        {
          /* WaitForSingleObject returns WAIT_FAILED, and we can only do
             some best-effort cleanup here.  */
          InterlockedDecrement (&mutex->counter);
          return 1;
        }
    }
  return 0;
}
 
static inline int
__gthread_recursive_mutex_trylock (__gthread_recursive_mutex_t *mutex)
{
  if (__gthread_active_p ())
    {
      DWORD me = GetCurrentThreadId();
      if (__GTHR_W32_InterlockedCompareExchange (&mutex->counter, 0, -1) < 0)
        {
          mutex->depth = 1;
          mutex->owner = me;
        }
      else if (mutex->owner == me)
        ++(mutex->depth);
      else
        return 1;
    }
  return 0;
}
 
static inline int
__gthread_recursive_mutex_unlock (__gthread_recursive_mutex_t *mutex)
{
  if (__gthread_active_p ())
    {
      --(mutex->depth);
      if (mutex->depth == 0)
        {
          mutex->owner = 0;
 
          if (InterlockedDecrement (&mutex->counter) >= 0)
            return ReleaseSemaphore (mutex->sema, 1, NULL) ? 0 : 1;
        }
    }
  return 0;
}
 
#endif /*  __GTHREAD_HIDE_WIN32API */
 
#ifdef __cplusplus
}
#endif
 
#endif /* _LIBOBJC */
 
#endif /* ! GCC_GTHR_WIN32_H */

Browse

Tools

Subversion Repositories openrisc

[/] [openrisc/] [trunk/] [gnu-old/] [gcc-4.2.2/] [gcc/] [gthr-win32.h] - Blame information for rev 867

Line No.	Rev	Author	Line
1	38	julius	`/* Threads compatibility routines for libgcc2 and libobjc. */`
2			`/* Compile this one with gcc. */`
3
4			`/* Copyright (C) 1999, 2000, 2002, 2003, 2004, 2005`
5			`Free Software Foundation, Inc.`
6			`Contributed by Mumit Khan <khan@xraylith.wisc.edu>.`
7
8			`This file is part of GCC.`
9
10			`GCC is free software; you can redistribute it and/or modify it under`
11			`the terms of the GNU General Public License as published by the Free`
12			`Software Foundation; either version 2, or (at your option) any later`
13			`version.`
14
15			`GCC is distributed in the hope that it will be useful, but WITHOUT ANY`
16			`WARRANTY; without even the implied warranty of MERCHANTABILITY or`
17			`FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License`
18			`for more details.`
19
20			`You should have received a copy of the GNU General Public License`
21			`along with GCC; see the file COPYING. If not, write to the Free`
22			`Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA`
23			`02110-1301, USA. */`
24
25			`/* As a special exception, if you link this library with other files,`
26			`some of which are compiled with GCC, to produce an executable,`
27			`this library does not by itself cause the resulting executable`
28			`to be covered by the GNU General Public License.`
29			`This exception does not however invalidate any other reasons why`
30			`the executable file might be covered by the GNU General Public License. */`
31
32			`#ifndef GCC_GTHR_WIN32_H`
33			`#define GCC_GTHR_WIN32_H`
34
35			`/* Windows32 threads specific definitions. The windows32 threading model`
36			`does not map well into pthread-inspired gcc's threading model, and so`
37			`there are caveats one needs to be aware of.`
38
39			`1. The destructor supplied to __gthread_key_create is ignored for`
40			`generic x86-win32 ports. This will certainly cause memory leaks`
41			`due to unreclaimed eh contexts (sizeof (eh_context) is at least`
42			`24 bytes for x86 currently).`
43
44			`This memory leak may be significant for long-running applications`
45			`that make heavy use of C++ EH.`
46
47			`However, Mingw runtime (version 0.3 or newer) provides a mechanism`
48			`to emulate pthreads key dtors; the runtime provides a special DLL,`
49			`linked in if -mthreads option is specified, that runs the dtors in`
50			`the reverse order of registration when each thread exits. If`
51			`-mthreads option is not given, a stub is linked in instead of the`
52			`DLL, which results in memory leak. Other x86-win32 ports can use`
53			`the same technique of course to avoid the leak.`
54
55			`2. The error codes returned are non-POSIX like, and cast into ints.`
56			`This may cause incorrect error return due to truncation values on`
57			`hw where sizeof (DWORD) > sizeof (int).`
58
59			`3. We are currently using a special mutex instead of the Critical`
60			`Sections, since Win9x does not support TryEnterCriticalSection`
61			`(while NT does).`
62
63			`The basic framework should work well enough. In the long term, GCC`
64			`needs to use Structured Exception Handling on Windows32. */`
65
66			`#define __GTHREADS 1`
67
68			`#include <errno.h>`
69			`#ifdef __MINGW32__`
70			`#include <_mingw.h>`
71			`#endif`
72
73			`#ifdef _LIBOBJC`
74
75			`/* This is necessary to prevent windef.h (included from windows.h) from`
76			`defining its own BOOL as a typedef. */`
77			`#ifndef __OBJC__`
78			`#define __OBJC__`
79			`#endif`
80			`#include <windows.h>`
81			`/* Now undef the windows BOOL. */`
82			`#undef BOOL`
83
84			`/* Key structure for maintaining thread specific storage */`
85			`static DWORD __gthread_objc_data_tls = (DWORD) -1;`
86
87			`/* Backend initialization functions */`
88
89			`/* Initialize the threads subsystem. */`
90			`int`
91			`__gthread_objc_init_thread_system (void)`
92			`{`
93			`/* Initialize the thread storage key. */`
94			`if ((__gthread_objc_data_tls = TlsAlloc ()) != (DWORD) -1)`
95			`return 0;`
96			`else`
97			`return -1;`
98			`}`
99
100			`/* Close the threads subsystem. */`
101			`int`
102			`__gthread_objc_close_thread_system (void)`
103			`{`
104			`if (__gthread_objc_data_tls != (DWORD) -1)`
105			`TlsFree (__gthread_objc_data_tls);`
106			`return 0;`
107			`}`
108
109			`/* Backend thread functions */`
110
111			`/* Create a new thread of execution. */`
112			`objc_thread_t`
113			`__gthread_objc_thread_detach (void (func)(void arg), void *arg)`
114			`{`
115			`DWORD thread_id = 0;`
116			`HANDLE win32_handle;`
117
118			`if (!(win32_handle = CreateThread (NULL, 0, (LPTHREAD_START_ROUTINE) func,`
119			`arg, 0, &thread_id)))`
120			`thread_id = 0;`
121
122			`return (objc_thread_t) thread_id;`
123			`}`
124
125			`/* Set the current thread's priority. */`
126			`int`
127			`__gthread_objc_thread_set_priority (int priority)`
128			`{`
129			`int sys_priority = 0;`
130
131			`switch (priority)`
132			`{`
133			`case OBJC_THREAD_INTERACTIVE_PRIORITY:`
134			`sys_priority = THREAD_PRIORITY_NORMAL;`
135			`break;`
136			`default:`
137			`case OBJC_THREAD_BACKGROUND_PRIORITY:`
138			`sys_priority = THREAD_PRIORITY_BELOW_NORMAL;`
139			`break;`
140			`case OBJC_THREAD_LOW_PRIORITY:`
141			`sys_priority = THREAD_PRIORITY_LOWEST;`
142			`break;`
143			`}`
144
145			`/* Change priority */`
146			`if (SetThreadPriority (GetCurrentThread (), sys_priority))`
147			`return 0;`
148			`else`
149			`return -1;`
150			`}`
151
152			`/* Return the current thread's priority. */`
153			`int`
154			`__gthread_objc_thread_get_priority (void)`
155			`{`
156			`int sys_priority;`
157
158			`sys_priority = GetThreadPriority (GetCurrentThread ());`
159
160			`switch (sys_priority)`
161			`{`
162			`case THREAD_PRIORITY_HIGHEST:`
163			`case THREAD_PRIORITY_TIME_CRITICAL:`
164			`case THREAD_PRIORITY_ABOVE_NORMAL:`
165			`case THREAD_PRIORITY_NORMAL:`
166			`return OBJC_THREAD_INTERACTIVE_PRIORITY;`
167
168			`default:`
169			`case THREAD_PRIORITY_BELOW_NORMAL:`
170			`return OBJC_THREAD_BACKGROUND_PRIORITY;`
171
172			`case THREAD_PRIORITY_IDLE:`
173			`case THREAD_PRIORITY_LOWEST:`
174			`return OBJC_THREAD_LOW_PRIORITY;`
175			`}`
176
177			`/* Couldn't get priority. */`
178			`return -1;`
179			`}`
180
181			`/* Yield our process time to another thread. */`
182			`void`
183			`__gthread_objc_thread_yield (void)`
184			`{`
185			`Sleep (0);`
186			`}`
187
188			`/* Terminate the current thread. */`
189			`int`
190			`__gthread_objc_thread_exit (void)`
191			`{`
192			`/* exit the thread */`
193			`ExitThread (__objc_thread_exit_status);`
194
195			`/* Failed if we reached here */`
196			`return -1;`
197			`}`
198
199			`/* Returns an integer value which uniquely describes a thread. */`
200			`objc_thread_t`
201			`__gthread_objc_thread_id (void)`
202			`{`
203			`return (objc_thread_t) GetCurrentThreadId ();`
204			`}`
205
206			`/* Sets the thread's local storage pointer. */`
207			`int`
208			`__gthread_objc_thread_set_data (void *value)`
209			`{`
210			`if (TlsSetValue (__gthread_objc_data_tls, value))`
211			`return 0;`
212			`else`
213			`return -1;`
214			`}`
215
216			`/* Returns the thread's local storage pointer. */`
217			`void *`
218			`__gthread_objc_thread_get_data (void)`
219			`{`
220			`DWORD lasterror;`
221			`void *ptr;`
222
223			`lasterror = GetLastError ();`
224
225			`ptr = TlsGetValue (__gthread_objc_data_tls); /* Return thread data. */`
226
227			`SetLastError (lasterror);`
228
229			`return ptr;`
230			`}`
231
232			`/* Backend mutex functions */`
233
234			`/* Allocate a mutex. */`
235			`int`
236			`__gthread_objc_mutex_allocate (objc_mutex_t mutex)`
237			`{`
238			`if ((mutex->backend = (void *) CreateMutex (NULL, 0, NULL)) == NULL)`
239			`return -1;`
240			`else`
241			`return 0;`
242			`}`
243
244			`/* Deallocate a mutex. */`
245			`int`
246			`__gthread_objc_mutex_deallocate (objc_mutex_t mutex)`
247			`{`
248			`CloseHandle ((HANDLE) (mutex->backend));`
249			`return 0;`
250			`}`
251
252			`/* Grab a lock on a mutex. */`
253			`int`
254			`__gthread_objc_mutex_lock (objc_mutex_t mutex)`
255			`{`
256			`int status;`
257
258			`status = WaitForSingleObject ((HANDLE) (mutex->backend), INFINITE);`
259			`if (status != WAIT_OBJECT_0 && status != WAIT_ABANDONED)`
260			`return -1;`
261			`else`
262			`return 0;`
263			`}`
264
265			`/* Try to grab a lock on a mutex. */`
266			`int`
267			`__gthread_objc_mutex_trylock (objc_mutex_t mutex)`
268			`{`
269			`int status;`
270
271			`status = WaitForSingleObject ((HANDLE) (mutex->backend), 0);`
272			`if (status != WAIT_OBJECT_0 && status != WAIT_ABANDONED)`
273			`return -1;`
274			`else`
275			`return 0;`
276			`}`
277
278			`/* Unlock the mutex */`
279			`int`
280			`__gthread_objc_mutex_unlock (objc_mutex_t mutex)`
281			`{`
282			`if (ReleaseMutex ((HANDLE) (mutex->backend)) == 0)`
283			`return -1;`
284			`else`
285			`return 0;`
286			`}`
287
288			`/* Backend condition mutex functions */`
289
290			`/* Allocate a condition. */`
291			`int`
292			`__gthread_objc_condition_allocate (objc_condition_t condition)`
293			`{`
294			`/* Unimplemented. */`
295			`return -1;`
296			`}`
297
298			`/* Deallocate a condition. */`
299			`int`
300			`__gthread_objc_condition_deallocate (objc_condition_t condition)`
301			`{`
302			`/* Unimplemented. */`
303			`return -1;`
304			`}`
305
306			`/* Wait on the condition */`
307			`int`
308			`__gthread_objc_condition_wait (objc_condition_t condition, objc_mutex_t mutex)`
309			`{`
310			`/* Unimplemented. */`
311			`return -1;`
312			`}`
313
314			`/* Wake up all threads waiting on this condition. */`
315			`int`
316			`__gthread_objc_condition_broadcast (objc_condition_t condition)`
317			`{`
318			`/* Unimplemented. */`
319			`return -1;`
320			`}`
321
322			`/* Wake up one thread waiting on this condition. */`
323			`int`
324			`__gthread_objc_condition_signal (objc_condition_t condition)`
325			`{`
326			`/* Unimplemented. */`
327			`return -1;`
328			`}`
329
330			`#else /* _LIBOBJC */`
331
332			`#ifdef __cplusplus`
333			`extern "C" {`
334			`#endif`
335
336			`typedef unsigned long __gthread_key_t;`
337
338			`typedef struct {`
339			`int done;`
340			`long started;`
341			`} __gthread_once_t;`
342
343			`typedef struct {`
344			`long counter;`
345			`void *sema;`
346			`} __gthread_mutex_t;`
347
348			`typedef struct {`
349			`long counter;`
350			`long depth;`
351			`unsigned long owner;`
352			`void *sema;`
353			`} __gthread_recursive_mutex_t;`
354
355			`#define __GTHREAD_ONCE_INIT {0, -1}`
356			`#define __GTHREAD_MUTEX_INIT_FUNCTION __gthread_mutex_init_function`
357			`#define __GTHREAD_MUTEX_INIT_DEFAULT {-1, 0}`
358			`#define __GTHREAD_RECURSIVE_MUTEX_INIT_FUNCTION \`
359			`__gthread_recursive_mutex_init_function`
360			`#define __GTHREAD_RECURSIVE_MUTEX_INIT_DEFAULT {-1, 0, 0, 0}`
361
362			`#if __MINGW32_MAJOR_VERSION >= 1 \|\| \`
363			`(__MINGW32_MAJOR_VERSION == 0 && __MINGW32_MINOR_VERSION > 2)`
364			`#define MINGW32_SUPPORTS_MT_EH 1`
365			`/* Mingw runtime >= v0.3 provides a magic variable that is set to nonzero`
366			`if -mthreads option was specified, or 0 otherwise. This is to get around`
367			`the lack of weak symbols in PE-COFF. */`
368			`extern int _CRT_MT;`
369			`extern int __mingwthr_key_dtor (unsigned long, void () (void ));`
370			`#endif /* __MINGW32__ version */`
371
372			`/* The Windows95 kernel does not export InterlockedCompareExchange.`
373			`This provides a substitute. When building apps that reference`
374			`gthread_mutex_try_lock, the __GTHREAD_I486_INLINE_LOCK_PRIMITIVES`
375			`macro must be defined if Windows95 is a target. Currently`
376			`gthread_mutex_try_lock is not referenced by libgcc or libstdc++. */`
377			`#ifdef __GTHREAD_I486_INLINE_LOCK_PRIMITIVES`
378			`static inline long`
379			`__gthr_i486_lock_cmp_xchg(long *dest, long xchg, long comperand)`
380			`{`
381			`long result;`
382			`__asm__ __volatile__ ("\n\`
383			`lock\n\`
384			`cmpxchg{l} {%4, %1\|%1, %4}\n"`
385			`: "=a" (result), "=m" (*dest)`
386			`: "0" (comperand), "m" (*dest), "r" (xchg)`
387			`: "cc");`
388			`return result;`
389			`}`
390			`#define __GTHR_W32_InterlockedCompareExchange __gthr_i486_lock_cmp_xchg`
391			`#else /* __GTHREAD_I486_INLINE_LOCK_PRIMITIVES */`
392			`#define __GTHR_W32_InterlockedCompareExchange InterlockedCompareExchange`
393			`#endif /* __GTHREAD_I486_INLINE_LOCK_PRIMITIVES */`
394
395			`static inline int`
396			`__gthread_active_p (void)`
397			`{`
398			`#ifdef MINGW32_SUPPORTS_MT_EH`
399			`return _CRT_MT;`
400			`#else`
401			`return 1;`
402			`#endif`
403			`}`
404
405			`#if __GTHREAD_HIDE_WIN32API`
406
407			`/* The implementations are in config/i386/gthr-win32.c in libgcc.a.`
408			`Only stubs are exposed to avoid polluting the C++ namespace with`
409			`windows api definitions. */`
410
411			`extern int __gthr_win32_once (__gthread_once_t , void () (void));`
412			`extern int __gthr_win32_key_create (__gthread_key_t , void () (void*));`
413			`extern int __gthr_win32_key_delete (__gthread_key_t);`
414			`extern void * __gthr_win32_getspecific (__gthread_key_t);`
415			`extern int __gthr_win32_setspecific (__gthread_key_t, const void *);`
416			`extern void __gthr_win32_mutex_init_function (__gthread_mutex_t *);`
417			`extern int __gthr_win32_mutex_lock (__gthread_mutex_t *);`
418			`extern int __gthr_win32_mutex_trylock (__gthread_mutex_t *);`
419			`extern int __gthr_win32_mutex_unlock (__gthread_mutex_t *);`
420			`extern void`
421			`__gthr_win32_recursive_mutex_init_function (__gthread_recursive_mutex_t *);`
422			`extern int __gthr_win32_recursive_mutex_lock (__gthread_recursive_mutex_t *);`
423			`extern int`
424			`__gthr_win32_recursive_mutex_trylock (__gthread_recursive_mutex_t *);`
425			`extern int __gthr_win32_recursive_mutex_unlock (__gthread_recursive_mutex_t *);`
426
427			`static inline int`
428			`__gthread_once (__gthread_once_t once, void (func) (void))`
429			`{`
430			`if (__gthread_active_p ())`
431			`return __gthr_win32_once (once, func);`
432			`else`
433			`return -1;`
434			`}`
435
436			`static inline int`
437			`__gthread_key_create (__gthread_key_t key, void (dtor) (void *))`
438			`{`
439			`return __gthr_win32_key_create (key, dtor);`
440			`}`
441
442			`static inline int`
443			`__gthread_key_delete (__gthread_key_t key)`
444			`{`
445			`return __gthr_win32_key_delete (key);`
446			`}`
447
448			`static inline void *`
449			`__gthread_getspecific (__gthread_key_t key)`
450			`{`
451			`return __gthr_win32_getspecific (key);`
452			`}`
453
454			`static inline int`
455			`__gthread_setspecific (__gthread_key_t key, const void *ptr)`
456			`{`
457			`return __gthr_win32_setspecific (key, ptr);`
458			`}`
459
460			`static inline void`
461			`__gthread_mutex_init_function (__gthread_mutex_t *mutex)`
462			`{`
463			`__gthr_win32_mutex_init_function (mutex);`
464			`}`
465
466			`static inline int`
467			`__gthread_mutex_lock (__gthread_mutex_t *mutex)`
468			`{`
469			`if (__gthread_active_p ())`
470			`return __gthr_win32_mutex_lock (mutex);`
471			`else`
472			`return 0;`
473			`}`
474
475			`static inline int`
476			`__gthread_mutex_trylock (__gthread_mutex_t *mutex)`
477			`{`
478			`if (__gthread_active_p ())`
479			`return __gthr_win32_mutex_trylock (mutex);`
480			`else`
481			`return 0;`
482			`}`
483
484			`static inline int`
485			`__gthread_mutex_unlock (__gthread_mutex_t *mutex)`
486			`{`
487			`if (__gthread_active_p ())`
488			`return __gthr_win32_mutex_unlock (mutex);`
489			`else`
490			`return 0;`
491			`}`
492
493			`static inline void`
494			`__gthread_recursive_mutex_init_function (__gthread_recursive_mutex_t *mutex)`
495			`{`
496			`__gthr_win32_recursive_mutex_init_function (mutex);`
497			`}`
498
499			`static inline int`
500			`__gthread_recursive_mutex_lock (__gthread_recursive_mutex_t *mutex)`
501			`{`
502			`if (__gthread_active_p ())`
503			`return __gthr_win32_recursive_mutex_lock (mutex);`
504			`else`
505			`return 0;`
506			`}`
507
508			`static inline int`
509			`__gthread_recursive_mutex_trylock (__gthread_recursive_mutex_t *mutex)`
510			`{`
511			`if (__gthread_active_p ())`
512			`return __gthr_win32_recursive_mutex_trylock (mutex);`
513			`else`
514			`return 0;`
515			`}`
516
517			`static inline int`
518			`__gthread_recursive_mutex_unlock (__gthread_recursive_mutex_t *mutex)`
519			`{`
520			`if (__gthread_active_p ())`
521			`return __gthr_win32_recursive_mutex_unlock (mutex);`
522			`else`
523			`return 0;`
524			`}`
525
526			`#else /* ! __GTHREAD_HIDE_WIN32API */`
527
528			`#include <windows.h>`
529			`#include <errno.h>`
530
531			`static inline int`
532			`__gthread_once (__gthread_once_t once, void (func) (void))`
533			`{`
534			`if (! __gthread_active_p ())`
535			`return -1;`
536			`else if (once == NULL \|\| func == NULL)`
537			`return EINVAL;`
538
539			`if (! once->done)`
540			`{`
541			`if (InterlockedIncrement (&(once->started)) == 0)`
542			`{`
543			`(*func) ();`
544			`once->done = TRUE;`
545			`}`
546			`else`
547			`{`
548			`/* Another thread is currently executing the code, so wait for it`
549			`to finish; yield the CPU in the meantime. If performance`
550			`does become an issue, the solution is to use an Event that`
551			`we wait on here (and set above), but that implies a place to`
552			`create the event before this routine is called. */`
553			`while (! once->done)`
554			`Sleep (0);`
555			`}`
556			`}`
557
558			`return 0;`
559			`}`
560
561			`/* Windows32 thread local keys don't support destructors; this leads to`
562			`leaks, especially in threaded applications making extensive use of`
563			`C++ EH. Mingw uses a thread-support DLL to work-around this problem. */`
564			`static inline int`
565			`__gthread_key_create (__gthread_key_t key, void (dtor) (void *))`
566			`{`
567			`int status = 0;`
568			`DWORD tls_index = TlsAlloc ();`
569			`if (tls_index != 0xFFFFFFFF)`
570			`{`
571			`*key = tls_index;`
572			`#ifdef MINGW32_SUPPORTS_MT_EH`
573			`/* Mingw runtime will run the dtors in reverse order for each thread`
574			`when the thread exits. */`
575			`status = __mingwthr_key_dtor (*key, dtor);`
576			`#endif`
577			`}`
578			`else`
579			`status = (int) GetLastError ();`
580			`return status;`
581			`}`
582
583			`static inline int`
584			`__gthread_key_delete (__gthread_key_t key)`
585			`{`
586			`return (TlsFree (key) != 0) ? 0 : (int) GetLastError ();`
587			`}`
588
589			`static inline void *`
590			`__gthread_getspecific (__gthread_key_t key)`
591			`{`
592			`DWORD lasterror;`
593			`void *ptr;`
594
595			`lasterror = GetLastError ();`
596
597			`ptr = TlsGetValue (key);`
598
599			`SetLastError (lasterror);`
600
601			`return ptr;`
602			`}`
603
604			`static inline int`
605			`__gthread_setspecific (__gthread_key_t key, const void *ptr)`
606			`{`
607			`return (TlsSetValue (key, (void*) ptr) != 0) ? 0 : (int) GetLastError ();`
608			`}`
609
610			`static inline void`
611			`__gthread_mutex_init_function (__gthread_mutex_t *mutex)`
612			`{`
613			`mutex->counter = -1;`
614			`mutex->sema = CreateSemaphore (NULL, 0, 65535, NULL);`
615			`}`
616
617			`static inline int`
618			`__gthread_mutex_lock (__gthread_mutex_t *mutex)`
619			`{`
620			`int status = 0;`
621
622			`if (__gthread_active_p ())`
623			`{`
624			`if (InterlockedIncrement (&mutex->counter) == 0 \|\|`
625			`WaitForSingleObject (mutex->sema, INFINITE) == WAIT_OBJECT_0)`
626			`status = 0;`
627			`else`
628			`{`
629			`/* WaitForSingleObject returns WAIT_FAILED, and we can only do`
630			`some best-effort cleanup here. */`
631			`InterlockedDecrement (&mutex->counter);`
632			`status = 1;`
633			`}`
634			`}`
635			`return status;`
636			`}`
637
638			`static inline int`
639			`__gthread_mutex_trylock (__gthread_mutex_t *mutex)`
640			`{`
641			`int status = 0;`
642
643			`if (__gthread_active_p ())`
644			`{`
645			`if (__GTHR_W32_InterlockedCompareExchange (&mutex->counter, 0, -1) < 0)`
646			`status = 0;`
647			`else`
648			`status = 1;`
649			`}`
650			`return status;`
651			`}`
652
653			`static inline int`
654			`__gthread_mutex_unlock (__gthread_mutex_t *mutex)`
655			`{`
656			`if (__gthread_active_p ())`
657			`{`
658			`if (InterlockedDecrement (&mutex->counter) >= 0)`
659			`return ReleaseSemaphore (mutex->sema, 1, NULL) ? 0 : 1;`
660			`}`
661			`return 0;`
662			`}`
663
664			`static inline void`
665			`__gthread_recursive_mutex_init_function (__gthread_recursive_mutex_t *mutex)`
666			`{`
667			`mutex->counter = -1;`
668			`mutex->depth = 0;`
669			`mutex->owner = 0;`
670			`mutex->sema = CreateSemaphore (NULL, 0, 65535, NULL);`
671			`}`
672
673			`static inline int`
674			`__gthread_recursive_mutex_lock (__gthread_recursive_mutex_t *mutex)`
675			`{`
676			`if (__gthread_active_p ())`
677			`{`
678			`DWORD me = GetCurrentThreadId();`
679			`if (InterlockedIncrement (&mutex->counter) == 0)`
680			`{`
681			`mutex->depth = 1;`
682			`mutex->owner = me;`
683			`}`
684			`else if (mutex->owner == me)`
685			`{`
686			`InterlockedDecrement (&mutex->counter);`
687			`++(mutex->depth);`
688			`}`
689			`else if (WaitForSingleObject (mutex->sema, INFINITE) == WAIT_OBJECT_0)`
690			`{`
691			`mutex->depth = 1;`
692			`mutex->owner = me;`
693			`}`
694			`else`
695			`{`
696			`/* WaitForSingleObject returns WAIT_FAILED, and we can only do`
697			`some best-effort cleanup here. */`
698			`InterlockedDecrement (&mutex->counter);`
699			`return 1;`
700			`}`
701			`}`
702			`return 0;`
703			`}`
704
705			`static inline int`
706			`__gthread_recursive_mutex_trylock (__gthread_recursive_mutex_t *mutex)`
707			`{`
708			`if (__gthread_active_p ())`
709			`{`
710			`DWORD me = GetCurrentThreadId();`
711			`if (__GTHR_W32_InterlockedCompareExchange (&mutex->counter, 0, -1) < 0)`
712			`{`
713			`mutex->depth = 1;`
714			`mutex->owner = me;`
715			`}`
716			`else if (mutex->owner == me)`
717			`++(mutex->depth);`
718			`else`
719			`return 1;`
720			`}`
721			`return 0;`
722			`}`
723
724			`static inline int`
725			`__gthread_recursive_mutex_unlock (__gthread_recursive_mutex_t *mutex)`
726			`{`
727			`if (__gthread_active_p ())`
728			`{`
729			`--(mutex->depth);`
730			`if (mutex->depth == 0)`
731			`{`
732			`mutex->owner = 0;`
733
734			`if (InterlockedDecrement (&mutex->counter) >= 0)`
735			`return ReleaseSemaphore (mutex->sema, 1, NULL) ? 0 : 1;`
736			`}`
737			`}`
738			`return 0;`
739			`}`
740
741			`#endif /* __GTHREAD_HIDE_WIN32API */`
742
743			`#ifdef __cplusplus`
744			`}`
745			`#endif`
746
747			`#endif /* _LIBOBJC */`
748
749			`#endif /* ! GCC_GTHR_WIN32_H */`