glib/gthread-win32.c - third_party/glib - Git at Google

 /* GLIB - Library of useful routines for C programming
  * Copyright (C) 1995-1997  Peter Mattis, Spencer Kimball and Josh MacDonald
  *
  * gthread.c: solaris thread system implementation
  * Copyright 1998-2001 Sebastian Wilhelmi; University of Karlsruhe
  * Copyright 2001 Hans Breuer
  *
  * SPDX-License-Identifier: LGPL-2.1-or-later
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
  * This library 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
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  */

 /*
  * Modified by the GLib Team and others 1997-2000.  See the AUTHORS
  * file for a list of people on the GLib Team.  See the ChangeLog
  * files for a list of changes.  These files are distributed with
  * GLib at ftp://ftp.gtk.org/pub/gtk/.
  */

 /* The GMutex and GCond implementations in this file are some of the
  * lowest-level code in GLib.  All other parts of GLib (messages,
  * memory, slices, etc) assume that they can freely use these facilities
  * without risking recursion.
  *
  * As such, these functions are NOT permitted to call any other part of
  * GLib.
  *
  * The thread manipulation functions (create, exit, join, etc.) have
  * more freedom -- they can do as they please.
  */

 #include "config.h"

 #include "glib.h"
 #include "glib-init.h"
 #include "gthread.h"
 #include "gthreadprivate.h"
 #include "gslice.h"

 #include <windows.h>

 #include <process.h>
 #include <stdlib.h>
 #include <stdio.h>

 static void
 g_thread_abort (gint         status,
                 const gchar *function)
 {
   fprintf (stderr, "GLib (gthread-win32.c): Unexpected error from C library during '%s': %s.  Aborting.\n",
            strerror (status), function);
   g_abort ();
 }

 /* Starting with Vista and Windows 2008, we have access to the
  * CONDITION_VARIABLE and SRWLock primitives on Windows, which are
  * pretty reasonable approximations of the primitives specified in
  * POSIX 2001 (pthread_cond_t and pthread_mutex_t respectively).
  *
  * Both of these types are structs containing a single pointer.  That
  * pointer is used as an atomic bitfield to support user-space mutexes
  * that only get the kernel involved in cases of contention (similar
  * to how futex()-based mutexes work on Linux).  The biggest advantage
  * of these new types is that they can be statically initialised to
  * zero.  That means that they are completely ABI compatible with our
  * GMutex and GCond APIs.
  */

 /* {{{1 GMutex */
 void
 g_mutex_init (GMutex *mutex)
 {
   InitializeSRWLock ((gpointer) mutex);
 }

 void
 g_mutex_clear (GMutex *mutex)
 {
 }

 void
 g_mutex_lock (GMutex *mutex)
 {
   AcquireSRWLockExclusive ((gpointer) mutex);
 }

 gboolean
 g_mutex_trylock (GMutex *mutex)
 {
   return TryAcquireSRWLockExclusive ((gpointer) mutex);
 }

 void
 g_mutex_unlock (GMutex *mutex)
 {
   ReleaseSRWLockExclusive ((gpointer) mutex);
 }

 /* {{{1 GRecMutex */

 static CRITICAL_SECTION *
 g_rec_mutex_impl_new (void)
 {
   CRITICAL_SECTION *cs;

   cs = g_slice_new (CRITICAL_SECTION);
   InitializeCriticalSection (cs);

   return cs;
 }

 static void
 g_rec_mutex_impl_free (CRITICAL_SECTION *cs)
 {
   DeleteCriticalSection (cs);
   g_slice_free (CRITICAL_SECTION, cs);
 }

 static CRITICAL_SECTION *
 g_rec_mutex_get_impl (GRecMutex *mutex)
 {
   CRITICAL_SECTION *impl = mutex->p;

   if G_UNLIKELY (mutex->p == NULL)
     {
       impl = g_rec_mutex_impl_new ();
       if (InterlockedCompareExchangePointer (&mutex->p, impl, NULL) != NULL)
         g_rec_mutex_impl_free (impl);
       impl = mutex->p;
     }

   return impl;
 }

 void
 g_rec_mutex_init (GRecMutex *mutex)
 {
   mutex->p = g_rec_mutex_impl_new ();
 }

 void
 g_rec_mutex_clear (GRecMutex *mutex)
 {
   g_rec_mutex_impl_free (mutex->p);
 }

 void
 g_rec_mutex_lock (GRecMutex *mutex)
 {
   EnterCriticalSection (g_rec_mutex_get_impl (mutex));
 }

 void
 g_rec_mutex_unlock (GRecMutex *mutex)
 {
   LeaveCriticalSection (mutex->p);
 }

 gboolean
 g_rec_mutex_trylock (GRecMutex *mutex)
 {
   return TryEnterCriticalSection (g_rec_mutex_get_impl (mutex));
 }

 /* {{{1 GRWLock */

 void
 g_rw_lock_init (GRWLock *lock)
 {
   InitializeSRWLock ((gpointer) lock);
 }

 void
 g_rw_lock_clear (GRWLock *lock)
 {
 }

 void
 g_rw_lock_writer_lock (GRWLock *lock)
 {
   AcquireSRWLockExclusive ((gpointer) lock);
 }

 gboolean
 g_rw_lock_writer_trylock (GRWLock *lock)
 {
   return TryAcquireSRWLockExclusive ((gpointer) lock);
 }

 void
 g_rw_lock_writer_unlock (GRWLock *lock)
 {
   ReleaseSRWLockExclusive ((gpointer) lock);
 }

 void
 g_rw_lock_reader_lock (GRWLock *lock)
 {
   AcquireSRWLockShared ((gpointer) lock);
 }

 gboolean
 g_rw_lock_reader_trylock (GRWLock *lock)
 {
   return TryAcquireSRWLockShared ((gpointer) lock);
 }

 void
 g_rw_lock_reader_unlock (GRWLock *lock)
 {
   ReleaseSRWLockShared ((gpointer) lock);
 }

 /* {{{1 GCond */
 void
 g_cond_init (GCond *cond)
 {
   InitializeConditionVariable ((gpointer) cond);
 }

 void
 g_cond_clear (GCond *cond)
 {
 }

 void
 g_cond_signal (GCond *cond)
 {
   WakeConditionVariable ((gpointer) cond);
 }

 void
 g_cond_broadcast (GCond *cond)
 {
   WakeAllConditionVariable ((gpointer) cond);
 }

 void
 g_cond_wait (GCond  *cond,
              GMutex *entered_mutex)
 {
   SleepConditionVariableSRW ((gpointer) cond, (gpointer) entered_mutex, INFINITE, 0);
 }

 gboolean
 g_cond_wait_until (GCond  *cond,
                    GMutex *entered_mutex,
                    gint64  end_time)
 {
   gint64 span, start_time;
   DWORD span_millis;
   gboolean signalled;

   start_time = g_get_monotonic_time ();
   do
     {
       span = end_time - start_time;

       if G_UNLIKELY (span < 0)
         span_millis = 0;
       else if G_UNLIKELY (span > G_GINT64_CONSTANT (1000) * (DWORD) INFINITE)
         span_millis = INFINITE;
       else
         /* Round up so we don't time out too early */
         span_millis = (span + 1000 - 1) / 1000;

       /* We never want to wait infinitely */
       if (span_millis >= INFINITE)
         span_millis = INFINITE - 1;

       signalled = SleepConditionVariableSRW ((gpointer) cond, (gpointer) entered_mutex, span_millis, 0);
       if (signalled)
         break;

       /* In case we didn't wait long enough after a timeout, wait again for the
        * remaining time */
       start_time = g_get_monotonic_time ();
     }
   while (start_time < end_time);

   return signalled;
 }

 /* {{{1 GPrivate */

 typedef struct _GPrivateDestructor GPrivateDestructor;

 struct _GPrivateDestructor
 {
   DWORD               index;
   GDestroyNotify      notify;
   GPrivateDestructor *next;
 };

 static GPrivateDestructor *g_private_destructors;  /* (atomic) prepend-only */
 static CRITICAL_SECTION g_private_lock;

 static DWORD
 g_private_get_impl (GPrivate *key)
 {
   DWORD impl = (DWORD) GPOINTER_TO_UINT(key->p);

   if G_UNLIKELY (impl == 0)
     {
       EnterCriticalSection (&g_private_lock);
       impl = (UINT_PTR) key->p;
       if (impl == 0)
         {
           GPrivateDestructor *destructor;

           impl = TlsAlloc ();

           if G_UNLIKELY (impl == 0)
             {
               /* Ignore TLS index 0 temporarily (as 0 is the indicator that we
                * haven't allocated TLS yet) and alloc again;
                * See https://gitlab.gnome.org/GNOME/glib/-/issues/2058 */
               DWORD impl2 = TlsAlloc ();
               TlsFree (impl);
               impl = impl2;
             }

           if (impl == TLS_OUT_OF_INDEXES || impl == 0)
             g_thread_abort (0, "TlsAlloc");

           if (key->notify != NULL)
             {
               destructor = malloc (sizeof (GPrivateDestructor));
               if G_UNLIKELY (destructor == NULL)
                 g_thread_abort (errno, "malloc");
               destructor->index = impl;
               destructor->notify = key->notify;
               destructor->next = g_atomic_pointer_get (&g_private_destructors);

               /* We need to do an atomic store due to the unlocked
                * access to the destructor list from the thread exit
                * function.
                *
                * It can double as a sanity check...
                */
               if (!g_atomic_pointer_compare_and_exchange (&g_private_destructors,
                                                           destructor->next,
                                                           destructor))
                 g_thread_abort (0, "g_private_get_impl(1)");
             }

           /* Ditto, due to the unlocked access on the fast path */
           if (!g_atomic_pointer_compare_and_exchange (&key->p, NULL, GUINT_TO_POINTER (impl)))
             g_thread_abort (0, "g_private_get_impl(2)");
         }
       LeaveCriticalSection (&g_private_lock);
     }

   return impl;
 }

 gpointer
 g_private_get (GPrivate *key)
 {
   return TlsGetValue (g_private_get_impl (key));
 }

 void
 g_private_set (GPrivate *key,
                gpointer  value)
 {
   TlsSetValue (g_private_get_impl (key), value);
 }

 void
 g_private_replace (GPrivate *key,
                    gpointer  value)
 {
   DWORD impl = g_private_get_impl (key);
   gpointer old;

   old = TlsGetValue (impl);
   TlsSetValue (impl, value);
   if (old && key->notify)
     key->notify (old);
 }

 /* {{{1 GThread */

 #define win32_check_for_error(what) G_STMT_START{			\
   if (!(what))								\
     g_error ("file %s: line %d (%s): error %s during %s",		\
 	     __FILE__, __LINE__, G_STRFUNC,				\
 	     g_win32_error_message (GetLastError ()), #what);		\
   }G_STMT_END

 #define G_MUTEX_SIZE (sizeof (gpointer))

 typedef BOOL (__stdcall *GTryEnterCriticalSectionFunc) (CRITICAL_SECTION *);

 typedef struct
 {
   GRealThread thread;

   GThreadFunc proxy;
   HANDLE      handle;
 } GThreadWin32;

 void
 g_system_thread_free (GRealThread *thread)
 {
   GThreadWin32 *wt = (GThreadWin32 *) thread;

   win32_check_for_error (CloseHandle (wt->handle));
   g_slice_free (GThreadWin32, wt);
 }

 void
 g_system_thread_exit (void)
 {
   _endthreadex (0);
 }

 static guint __stdcall
 g_thread_win32_proxy (gpointer data)
 {
   GThreadWin32 *self = data;

   self->proxy (self);

   g_system_thread_exit ();

   g_assert_not_reached ();

   return 0;
 }

 GRealThread *
 g_system_thread_new (GThreadFunc proxy,
                      gulong stack_size,
                      const char *name,
                      GThreadFunc func,
                      gpointer data,
                      GError **error)
 {
   GThreadWin32 *thread;
   GRealThread *base_thread;
   guint ignore;
   const gchar *message = NULL;
   int thread_prio;

   thread = g_slice_new0 (GThreadWin32);
   thread->proxy = proxy;
   thread->handle = (HANDLE) NULL;
   base_thread = (GRealThread*)thread;
   base_thread->ref_count = 2;
   base_thread->ours = TRUE;
   base_thread->thread.joinable = TRUE;
   base_thread->thread.func = func;
   base_thread->thread.data = data;
   base_thread->name = g_strdup (name);

   thread->handle = (HANDLE) _beginthreadex (NULL, stack_size, g_thread_win32_proxy, thread,
                                             CREATE_SUSPENDED, &ignore);

   if (thread->handle == NULL)
     {
       message = "Error creating thread";
       goto error;
     }

   /* For thread priority inheritance we need to manually set the thread
    * priority of the new thread to the priority of the current thread. We
    * also have to start the thread suspended and resume it after actually
    * setting the priority here.
    *
    * On Windows, by default all new threads are created with NORMAL thread
    * priority.
    */
   {
     HANDLE current_thread = GetCurrentThread ();
     thread_prio = GetThreadPriority (current_thread);
   }

   if (thread_prio == THREAD_PRIORITY_ERROR_RETURN)
     {
       message = "Error getting current thread priority";
       goto error;
     }

   if (SetThreadPriority (thread->handle, thread_prio) == 0)
     {
       message = "Error setting new thread priority";
       goto error;
     }

   if (ResumeThread (thread->handle) == (DWORD) -1)
     {
       message = "Error resuming new thread";
       goto error;
     }

   return (GRealThread *) thread;

 error:
   {
     gchar *win_error = g_win32_error_message (GetLastError ());
     g_set_error (error, G_THREAD_ERROR, G_THREAD_ERROR_AGAIN,
                  "%s: %s", message, win_error);
     g_free (win_error);
     if (thread->handle)
       CloseHandle (thread->handle);
     g_slice_free (GThreadWin32, thread);
     return NULL;
   }
 }

 void
 g_thread_yield (void)
 {
   Sleep(0);
 }

 void
 g_system_thread_wait (GRealThread *thread)
 {
   GThreadWin32 *wt = (GThreadWin32 *) thread;

   win32_check_for_error (WAIT_FAILED != WaitForSingleObject (wt->handle, INFINITE));
 }

 #define EXCEPTION_SET_THREAD_NAME ((DWORD) 0x406D1388)

 #ifndef _MSC_VER
 static void *SetThreadName_VEH_handle = NULL;

 static LONG __stdcall
 SetThreadName_VEH (PEXCEPTION_POINTERS ExceptionInfo)
 {
   if (ExceptionInfo->ExceptionRecord != NULL &&
       ExceptionInfo->ExceptionRecord->ExceptionCode == EXCEPTION_SET_THREAD_NAME)
     return EXCEPTION_CONTINUE_EXECUTION;

   return EXCEPTION_CONTINUE_SEARCH;
 }
 #endif

 typedef struct _THREADNAME_INFO
 {
   DWORD  dwType;	/* must be 0x1000 */
   LPCSTR szName;	/* pointer to name (in user addr space) */
   DWORD  dwThreadID;	/* thread ID (-1=caller thread) */
   DWORD  dwFlags;	/* reserved for future use, must be zero */
 } THREADNAME_INFO;

 static void
 SetThreadName (DWORD  dwThreadID,
                LPCSTR szThreadName)
 {
    THREADNAME_INFO info;
    DWORD infosize;

    info.dwType = 0x1000;
    info.szName = szThreadName;
    info.dwThreadID = dwThreadID;
    info.dwFlags = 0;

    infosize = sizeof (info) / sizeof (ULONG_PTR);

 #ifdef _MSC_VER
    __try
      {
        RaiseException (EXCEPTION_SET_THREAD_NAME, 0, infosize,
                        (const ULONG_PTR *) &info);
      }
    __except (GetExceptionCode () == EXCEPTION_SET_THREAD_NAME ?
              EXCEPTION_EXECUTE_HANDLER : EXCEPTION_CONTINUE_SEARCH)
      {
      }
 #else
    if ((!IsDebuggerPresent ()) || (SetThreadName_VEH_handle == NULL))
      return;

    RaiseException (EXCEPTION_SET_THREAD_NAME, 0, infosize, (const ULONG_PTR *) &info);
 #endif
 }

 typedef HRESULT (WINAPI *pSetThreadDescription) (HANDLE hThread,
                                                  PCWSTR lpThreadDescription);
 static pSetThreadDescription SetThreadDescriptionFunc = NULL;
 static HMODULE kernel32_module = NULL;

 static gboolean
 g_thread_win32_load_library (void)
 {
   /* FIXME: Add support for UWP app */
 #if !defined(G_WINAPI_ONLY_APP)
   static gsize _init_once = 0;
   if (g_once_init_enter (&_init_once))
     {
       kernel32_module = LoadLibraryW (L"kernel32.dll");
       if (kernel32_module)
         {
           SetThreadDescriptionFunc =
               (pSetThreadDescription) GetProcAddress (kernel32_module,
                                                       "SetThreadDescription");
           if (!SetThreadDescriptionFunc)
             FreeLibrary (kernel32_module);
         }
       g_once_init_leave (&_init_once, 1);
     }
 #endif

   return !!SetThreadDescriptionFunc;
 }

 static gboolean
 g_thread_win32_set_thread_desc (const gchar *name)
 {
   HRESULT hr;
   wchar_t *namew;

   if (!g_thread_win32_load_library () || !name)
     return FALSE;

   namew = g_utf8_to_utf16 (name, -1, NULL, NULL, NULL);
   if (!namew)
     return FALSE;

   hr = SetThreadDescriptionFunc (GetCurrentThread (), namew);

   g_free (namew);
   return SUCCEEDED (hr);
 }

 void
 g_system_thread_set_name (const gchar *name)
 {
   /* Prefer SetThreadDescription over exception based way if available,
    * since thread description set by SetThreadDescription will be preserved
    * in dump file */
   if (!g_thread_win32_set_thread_desc (name))
     SetThreadName ((DWORD) -1, name);
 }

 /* {{{1 Epilogue */

 void
 g_thread_win32_init (void)
 {
   InitializeCriticalSection (&g_private_lock);

 #ifndef _MSC_VER
   /* Set the handler as last to not interfere with ASAN runtimes.
    * Many ASAN implementations (currently all three of GCC, CLANG
    * and MSVC) install a Vectored Exception Handler that must be
    * first in the sequence to work well
    */
   SetThreadName_VEH_handle = AddVectoredExceptionHandler (0, &SetThreadName_VEH);
   if (SetThreadName_VEH_handle == NULL)
     g_critical ("%s failed with error code %u",
                 "AddVectoredExceptionHandler", (unsigned int) GetLastError ());
 #endif
 }

 void
 g_thread_win32_thread_detach (void)
 {
   gboolean dtors_called;

   do
     {
       GPrivateDestructor *dtor;

       /* We go by the POSIX book on this one.
        *
        * If we call a destructor then there is a chance that some new
        * TLS variables got set by code called in that destructor.
        *
        * Loop until nothing is left.
        */
       dtors_called = FALSE;

       for (dtor = g_atomic_pointer_get (&g_private_destructors); dtor; dtor = dtor->next)
         {
           gpointer value;

           value = TlsGetValue (dtor->index);
           if (value != NULL && dtor->notify != NULL)
             {
               /* POSIX says to clear this before the call */
               TlsSetValue (dtor->index, NULL);
               dtor->notify (value);
               dtors_called = TRUE;
             }
         }
     }
   while (dtors_called);
 }

 void
 g_thread_win32_process_detach (void)
 {
 #ifndef _MSC_VER
   if (SetThreadName_VEH_handle != NULL)
     {
       RemoveVectoredExceptionHandler (SetThreadName_VEH_handle);
       SetThreadName_VEH_handle = NULL;
     }
 #endif
 }

 /* vim:set foldmethod=marker: */
	/* GLIB - Library of useful routines for C programming
	* Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
	*
	* gthread.c: solaris thread system implementation
	* Copyright 1998-2001 Sebastian Wilhelmi; University of Karlsruhe
	* Copyright 2001 Hans Breuer
	*
	* SPDX-License-Identifier: LGPL-2.1-or-later
	*
	* This library is free software; you can redistribute it and/or
	* modify it under the terms of the GNU Lesser General Public
	* License as published by the Free Software Foundation; either
	* version 2.1 of the License, or (at your option) any later version.
	*
	* This library 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
	* Lesser General Public License for more details.
	*
	* You should have received a copy of the GNU Lesser General Public
	* License along with this library; if not, see <http://www.gnu.org/licenses/>.
	*/

	/*
	* Modified by the GLib Team and others 1997-2000. See the AUTHORS
	* file for a list of people on the GLib Team. See the ChangeLog
	* files for a list of changes. These files are distributed with
	* GLib at ftp://ftp.gtk.org/pub/gtk/.
	*/

	/* The GMutex and GCond implementations in this file are some of the
	* lowest-level code in GLib. All other parts of GLib (messages,
	* memory, slices, etc) assume that they can freely use these facilities
	* without risking recursion.
	*
	* As such, these functions are NOT permitted to call any other part of
	* GLib.
	*
	* The thread manipulation functions (create, exit, join, etc.) have
	* more freedom -- they can do as they please.
	*/

	#include "config.h"

	#include "glib.h"
	#include "glib-init.h"
	#include "gthread.h"
	#include "gthreadprivate.h"
	#include "gslice.h"

	#include <windows.h>

	#include <process.h>
	#include <stdlib.h>
	#include <stdio.h>

	static void
	g_thread_abort (gint status,
	const gchar *function)
	{
	fprintf (stderr, "GLib (gthread-win32.c): Unexpected error from C library during '%s': %s. Aborting.\n",
	strerror (status), function);
	g_abort ();
	}

	/* Starting with Vista and Windows 2008, we have access to the
	* CONDITION_VARIABLE and SRWLock primitives on Windows, which are
	* pretty reasonable approximations of the primitives specified in
	* POSIX 2001 (pthread_cond_t and pthread_mutex_t respectively).
	*
	* Both of these types are structs containing a single pointer. That
	* pointer is used as an atomic bitfield to support user-space mutexes
	* that only get the kernel involved in cases of contention (similar
	* to how futex()-based mutexes work on Linux). The biggest advantage
	* of these new types is that they can be statically initialised to
	* zero. That means that they are completely ABI compatible with our
	* GMutex and GCond APIs.
	*/

	/* {{{1 GMutex */
	void
	g_mutex_init (GMutex *mutex)
	{
	InitializeSRWLock ((gpointer) mutex);
	}

	void
	g_mutex_clear (GMutex *mutex)
	{
	}

	void
	g_mutex_lock (GMutex *mutex)
	{
	AcquireSRWLockExclusive ((gpointer) mutex);
	}

	gboolean
	g_mutex_trylock (GMutex *mutex)
	{
	return TryAcquireSRWLockExclusive ((gpointer) mutex);
	}

	void
	g_mutex_unlock (GMutex *mutex)
	{
	ReleaseSRWLockExclusive ((gpointer) mutex);
	}

	/* {{{1 GRecMutex */

	static CRITICAL_SECTION *
	g_rec_mutex_impl_new (void)
	{
	CRITICAL_SECTION *cs;

	cs = g_slice_new (CRITICAL_SECTION);
	InitializeCriticalSection (cs);

	return cs;
	}

	static void
	g_rec_mutex_impl_free (CRITICAL_SECTION *cs)
	{
	DeleteCriticalSection (cs);
	g_slice_free (CRITICAL_SECTION, cs);
	}

	static CRITICAL_SECTION *
	g_rec_mutex_get_impl (GRecMutex *mutex)
	{
	CRITICAL_SECTION *impl = mutex->p;

	if G_UNLIKELY (mutex->p == NULL)
	{
	impl = g_rec_mutex_impl_new ();
	if (InterlockedCompareExchangePointer (&mutex->p, impl, NULL) != NULL)
	g_rec_mutex_impl_free (impl);
	impl = mutex->p;
	}

	return impl;
	}

	void
	g_rec_mutex_init (GRecMutex *mutex)
	{
	mutex->p = g_rec_mutex_impl_new ();
	}

	void
	g_rec_mutex_clear (GRecMutex *mutex)
	{
	g_rec_mutex_impl_free (mutex->p);
	}

	void
	g_rec_mutex_lock (GRecMutex *mutex)
	{
	EnterCriticalSection (g_rec_mutex_get_impl (mutex));
	}

	void
	g_rec_mutex_unlock (GRecMutex *mutex)
	{
	LeaveCriticalSection (mutex->p);
	}

	gboolean
	g_rec_mutex_trylock (GRecMutex *mutex)
	{
	return TryEnterCriticalSection (g_rec_mutex_get_impl (mutex));
	}

	/* {{{1 GRWLock */

	void
	g_rw_lock_init (GRWLock *lock)
	{
	InitializeSRWLock ((gpointer) lock);
	}

	void
	g_rw_lock_clear (GRWLock *lock)
	{
	}

	void
	g_rw_lock_writer_lock (GRWLock *lock)
	{
	AcquireSRWLockExclusive ((gpointer) lock);
	}

	gboolean
	g_rw_lock_writer_trylock (GRWLock *lock)
	{
	return TryAcquireSRWLockExclusive ((gpointer) lock);
	}

	void
	g_rw_lock_writer_unlock (GRWLock *lock)
	{
	ReleaseSRWLockExclusive ((gpointer) lock);
	}

	void
	g_rw_lock_reader_lock (GRWLock *lock)
	{
	AcquireSRWLockShared ((gpointer) lock);
	}

	gboolean
	g_rw_lock_reader_trylock (GRWLock *lock)
	{
	return TryAcquireSRWLockShared ((gpointer) lock);
	}

	void
	g_rw_lock_reader_unlock (GRWLock *lock)
	{
	ReleaseSRWLockShared ((gpointer) lock);
	}

	/* {{{1 GCond */
	void
	g_cond_init (GCond *cond)
	{
	InitializeConditionVariable ((gpointer) cond);
	}

	void
	g_cond_clear (GCond *cond)
	{
	}

	void
	g_cond_signal (GCond *cond)
	{
	WakeConditionVariable ((gpointer) cond);
	}

	void
	g_cond_broadcast (GCond *cond)
	{
	WakeAllConditionVariable ((gpointer) cond);
	}

	void
	g_cond_wait (GCond *cond,
	GMutex *entered_mutex)
	{
	SleepConditionVariableSRW ((gpointer) cond, (gpointer) entered_mutex, INFINITE, 0);
	}

	gboolean
	g_cond_wait_until (GCond *cond,
	GMutex *entered_mutex,
	gint64 end_time)
	{
	gint64 span, start_time;
	DWORD span_millis;
	gboolean signalled;

	start_time = g_get_monotonic_time ();
	do
	{
	span = end_time - start_time;

	if G_UNLIKELY (span < 0)
	span_millis = 0;
	else if G_UNLIKELY (span > G_GINT64_CONSTANT (1000) * (DWORD) INFINITE)
	span_millis = INFINITE;
	else
	/* Round up so we don't time out too early */
	span_millis = (span + 1000 - 1) / 1000;

	/* We never want to wait infinitely */
	if (span_millis >= INFINITE)
	span_millis = INFINITE - 1;

	signalled = SleepConditionVariableSRW ((gpointer) cond, (gpointer) entered_mutex, span_millis, 0);
	if (signalled)
	break;

	/* In case we didn't wait long enough after a timeout, wait again for the
	* remaining time */
	start_time = g_get_monotonic_time ();
	}
	while (start_time < end_time);

	return signalled;
	}

	/* {{{1 GPrivate */

	typedef struct _GPrivateDestructor GPrivateDestructor;

	struct _GPrivateDestructor
	{
	DWORD index;
	GDestroyNotify notify;
	GPrivateDestructor *next;
	};

	static GPrivateDestructor g_private_destructors; / (atomic) prepend-only */
	static CRITICAL_SECTION g_private_lock;

	static DWORD
	g_private_get_impl (GPrivate *key)
	{
	DWORD impl = (DWORD) GPOINTER_TO_UINT(key->p);

	if G_UNLIKELY (impl == 0)
	{
	EnterCriticalSection (&g_private_lock);
	impl = (UINT_PTR) key->p;
	if (impl == 0)
	{
	GPrivateDestructor *destructor;

	impl = TlsAlloc ();

	if G_UNLIKELY (impl == 0)
	{
	/* Ignore TLS index 0 temporarily (as 0 is the indicator that we
	* haven't allocated TLS yet) and alloc again;
	* See https://gitlab.gnome.org/GNOME/glib/-/issues/2058 */
	DWORD impl2 = TlsAlloc ();
	TlsFree (impl);
	impl = impl2;
	}

	if (impl == TLS_OUT_OF_INDEXES \|\| impl == 0)
	g_thread_abort (0, "TlsAlloc");

	if (key->notify != NULL)
	{
	destructor = malloc (sizeof (GPrivateDestructor));
	if G_UNLIKELY (destructor == NULL)
	g_thread_abort (errno, "malloc");
	destructor->index = impl;
	destructor->notify = key->notify;
	destructor->next = g_atomic_pointer_get (&g_private_destructors);

	/* We need to do an atomic store due to the unlocked
	* access to the destructor list from the thread exit
	* function.
	*
	* It can double as a sanity check...
	*/
	if (!g_atomic_pointer_compare_and_exchange (&g_private_destructors,
	destructor->next,
	destructor))
	g_thread_abort (0, "g_private_get_impl(1)");
	}

	/* Ditto, due to the unlocked access on the fast path */
	if (!g_atomic_pointer_compare_and_exchange (&key->p, NULL, GUINT_TO_POINTER (impl)))
	g_thread_abort (0, "g_private_get_impl(2)");
	}
	LeaveCriticalSection (&g_private_lock);
	}

	return impl;
	}

	gpointer
	g_private_get (GPrivate *key)
	{
	return TlsGetValue (g_private_get_impl (key));
	}

	void
	g_private_set (GPrivate *key,
	gpointer value)
	{
	TlsSetValue (g_private_get_impl (key), value);
	}

	void
	g_private_replace (GPrivate *key,
	gpointer value)
	{
	DWORD impl = g_private_get_impl (key);
	gpointer old;

	old = TlsGetValue (impl);
	TlsSetValue (impl, value);
	if (old && key->notify)
	key->notify (old);
	}

	/* {{{1 GThread */

	#define win32_check_for_error(what) G_STMT_START{ \
	if (!(what)) \
	g_error ("file %s: line %d (%s): error %s during %s", \
	__FILE__, __LINE__, G_STRFUNC, \
	g_win32_error_message (GetLastError ()), #what); \
	}G_STMT_END

	#define G_MUTEX_SIZE (sizeof (gpointer))

	typedef BOOL (__stdcall GTryEnterCriticalSectionFunc) (CRITICAL_SECTION );

	typedef struct
	{
	GRealThread thread;

	GThreadFunc proxy;
	HANDLE handle;
	} GThreadWin32;

	void
	g_system_thread_free (GRealThread *thread)
	{
	GThreadWin32 wt = (GThreadWin32 ) thread;

	win32_check_for_error (CloseHandle (wt->handle));
	g_slice_free (GThreadWin32, wt);
	}

	void
	g_system_thread_exit (void)
	{
	_endthreadex (0);
	}

	static guint __stdcall
	g_thread_win32_proxy (gpointer data)
	{
	GThreadWin32 *self = data;

	self->proxy (self);

	g_system_thread_exit ();

	g_assert_not_reached ();

	return 0;
	}

	GRealThread *
	g_system_thread_new (GThreadFunc proxy,
	gulong stack_size,
	const char *name,
	GThreadFunc func,
	gpointer data,
	GError **error)
	{
	GThreadWin32 *thread;
	GRealThread *base_thread;
	guint ignore;
	const gchar *message = NULL;
	int thread_prio;

	thread = g_slice_new0 (GThreadWin32);
	thread->proxy = proxy;
	thread->handle = (HANDLE) NULL;
	base_thread = (GRealThread*)thread;
	base_thread->ref_count = 2;
	base_thread->ours = TRUE;
	base_thread->thread.joinable = TRUE;
	base_thread->thread.func = func;
	base_thread->thread.data = data;
	base_thread->name = g_strdup (name);

	thread->handle = (HANDLE) _beginthreadex (NULL, stack_size, g_thread_win32_proxy, thread,
	CREATE_SUSPENDED, &ignore);

	if (thread->handle == NULL)
	{
	message = "Error creating thread";
	goto error;
	}

	/* For thread priority inheritance we need to manually set the thread
	* priority of the new thread to the priority of the current thread. We
	* also have to start the thread suspended and resume it after actually
	* setting the priority here.
	*
	* On Windows, by default all new threads are created with NORMAL thread
	* priority.
	*/
	{
	HANDLE current_thread = GetCurrentThread ();
	thread_prio = GetThreadPriority (current_thread);
	}

	if (thread_prio == THREAD_PRIORITY_ERROR_RETURN)
	{
	message = "Error getting current thread priority";
	goto error;
	}

	if (SetThreadPriority (thread->handle, thread_prio) == 0)
	{
	message = "Error setting new thread priority";
	goto error;
	}

	if (ResumeThread (thread->handle) == (DWORD) -1)
	{
	message = "Error resuming new thread";
	goto error;
	}

	return (GRealThread *) thread;

	error:
	{
	gchar *win_error = g_win32_error_message (GetLastError ());
	g_set_error (error, G_THREAD_ERROR, G_THREAD_ERROR_AGAIN,
	"%s: %s", message, win_error);
	g_free (win_error);
	if (thread->handle)
	CloseHandle (thread->handle);
	g_slice_free (GThreadWin32, thread);
	return NULL;
	}
	}

	void
	g_thread_yield (void)
	{
	Sleep(0);
	}

	void
	g_system_thread_wait (GRealThread *thread)
	{
	GThreadWin32 wt = (GThreadWin32 ) thread;

	win32_check_for_error (WAIT_FAILED != WaitForSingleObject (wt->handle, INFINITE));
	}

	#define EXCEPTION_SET_THREAD_NAME ((DWORD) 0x406D1388)

	#ifndef _MSC_VER
	static void *SetThreadName_VEH_handle = NULL;

	static LONG __stdcall
	SetThreadName_VEH (PEXCEPTION_POINTERS ExceptionInfo)
	{
	if (ExceptionInfo->ExceptionRecord != NULL &&
	ExceptionInfo->ExceptionRecord->ExceptionCode == EXCEPTION_SET_THREAD_NAME)
	return EXCEPTION_CONTINUE_EXECUTION;

	return EXCEPTION_CONTINUE_SEARCH;
	}
	#endif

	typedef struct _THREADNAME_INFO
	{
	DWORD dwType; /* must be 0x1000 */
	LPCSTR szName; /* pointer to name (in user addr space) */
	DWORD dwThreadID; /* thread ID (-1=caller thread) */
	DWORD dwFlags; /* reserved for future use, must be zero */
	} THREADNAME_INFO;

	static void
	SetThreadName (DWORD dwThreadID,
	LPCSTR szThreadName)
	{
	THREADNAME_INFO info;
	DWORD infosize;

	info.dwType = 0x1000;
	info.szName = szThreadName;
	info.dwThreadID = dwThreadID;
	info.dwFlags = 0;

	infosize = sizeof (info) / sizeof (ULONG_PTR);

	#ifdef _MSC_VER
	__try
	{
	RaiseException (EXCEPTION_SET_THREAD_NAME, 0, infosize,
	(const ULONG_PTR *) &info);
	}
	__except (GetExceptionCode () == EXCEPTION_SET_THREAD_NAME ?
	EXCEPTION_EXECUTE_HANDLER : EXCEPTION_CONTINUE_SEARCH)
	{
	}
	#else
	if ((!IsDebuggerPresent ()) \|\| (SetThreadName_VEH_handle == NULL))
	return;

	RaiseException (EXCEPTION_SET_THREAD_NAME, 0, infosize, (const ULONG_PTR *) &info);
	#endif
	}

	typedef HRESULT (WINAPI *pSetThreadDescription) (HANDLE hThread,
	PCWSTR lpThreadDescription);
	static pSetThreadDescription SetThreadDescriptionFunc = NULL;
	static HMODULE kernel32_module = NULL;

	static gboolean
	g_thread_win32_load_library (void)
	{
	/* FIXME: Add support for UWP app */
	#if !defined(G_WINAPI_ONLY_APP)
	static gsize _init_once = 0;
	if (g_once_init_enter (&_init_once))
	{
	kernel32_module = LoadLibraryW (L"kernel32.dll");
	if (kernel32_module)
	{
	SetThreadDescriptionFunc =
	(pSetThreadDescription) GetProcAddress (kernel32_module,
	"SetThreadDescription");
	if (!SetThreadDescriptionFunc)
	FreeLibrary (kernel32_module);
	}
	g_once_init_leave (&_init_once, 1);
	}
	#endif

	return !!SetThreadDescriptionFunc;
	}

	static gboolean
	g_thread_win32_set_thread_desc (const gchar *name)
	{
	HRESULT hr;
	wchar_t *namew;

	if (!g_thread_win32_load_library () \|\| !name)
	return FALSE;

	namew = g_utf8_to_utf16 (name, -1, NULL, NULL, NULL);
	if (!namew)
	return FALSE;

	hr = SetThreadDescriptionFunc (GetCurrentThread (), namew);

	g_free (namew);
	return SUCCEEDED (hr);
	}

	void
	g_system_thread_set_name (const gchar *name)
	{
	/* Prefer SetThreadDescription over exception based way if available,
	* since thread description set by SetThreadDescription will be preserved
	* in dump file */
	if (!g_thread_win32_set_thread_desc (name))
	SetThreadName ((DWORD) -1, name);
	}

	/* {{{1 Epilogue */

	void
	g_thread_win32_init (void)
	{
	InitializeCriticalSection (&g_private_lock);

	#ifndef _MSC_VER
	/* Set the handler as last to not interfere with ASAN runtimes.
	* Many ASAN implementations (currently all three of GCC, CLANG
	* and MSVC) install a Vectored Exception Handler that must be
	* first in the sequence to work well
	*/
	SetThreadName_VEH_handle = AddVectoredExceptionHandler (0, &SetThreadName_VEH);
	if (SetThreadName_VEH_handle == NULL)
	g_critical ("%s failed with error code %u",
	"AddVectoredExceptionHandler", (unsigned int) GetLastError ());
	#endif
	}

	void
	g_thread_win32_thread_detach (void)
	{
	gboolean dtors_called;

	do
	{
	GPrivateDestructor *dtor;

	/* We go by the POSIX book on this one.
	*
	* If we call a destructor then there is a chance that some new
	* TLS variables got set by code called in that destructor.
	*
	* Loop until nothing is left.
	*/
	dtors_called = FALSE;

	for (dtor = g_atomic_pointer_get (&g_private_destructors); dtor; dtor = dtor->next)
	{
	gpointer value;

	value = TlsGetValue (dtor->index);
	if (value != NULL && dtor->notify != NULL)
	{
	/* POSIX says to clear this before the call */
	TlsSetValue (dtor->index, NULL);
	dtor->notify (value);
	dtors_called = TRUE;
	}
	}
	}
	while (dtors_called);
	}

	void
	g_thread_win32_process_detach (void)
	{
	#ifndef _MSC_VER
	if (SetThreadName_VEH_handle != NULL)
	{
	RemoveVectoredExceptionHandler (SetThreadName_VEH_handle);
	SetThreadName_VEH_handle = NULL;
	}
	#endif
	}

	/* vim:set foldmethod=marker: */