-/* Threads compatibility routines for libgcc2. */
+/* Threads compatibility routines for libgcc2 and libobjc. */
/* Compile this one with gcc. */
-/* Copyright (C) 1999, 2000 Free Software Foundation, Inc.
+
+/* 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 GNU CC.
+This file is part of GCC.
-GNU CC 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 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.
-GNU CC 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.
+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 GNU CC; see the file COPYING. If not, write to
-the Free Software Foundation, 59 Temple Place - Suite 330,
-Boston, MA 02111-1307, USA. */
+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 exception does not however invalidate any other reasons why
the executable file might be covered by the GNU General Public License. */
-#ifndef __gthr_win32_h
-#define __gthr_win32_h
+#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
+ 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
+ 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
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
+ 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
+ This may cause incorrect error return due to truncation values on
hw where sizeof (DWORD) > sizeof (int).
-
- 3. We might consider using Critical Sections instead of Windows32
- mutexes for better performance, but emulating __gthread_mutex_trylock
- interface becomes more complicated (Win9x does not support
- TryEnterCriticalSectioni, while NT does).
-
+
+ 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 <windows.h>
#include <errno.h>
#ifdef __MINGW32__
#include <_mingw.h>
#endif
-typedef DWORD __gthread_key_t;
+#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 HANDLE __gthread_mutex_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 {FALSE, -1}
+#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
-extern int __mingwthr_key_dtor PARAMS ((DWORD, void (*) (void *)));
-/* Mingw runtime >= v0.3 provides a magic variable that is set to non-zero
- if -mthreads option was specified, or 0 otherwise. This is to get around
+/* 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;
-#endif
+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 ()
+__gthread_active_p (void)
{
#ifdef MINGW32_SUPPORTS_MT_EH
return _CRT_MT;
#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) ())
+__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;
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. */
+ /* 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
+ 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 *))
return status;
}
-/* Currently, this routine is called only for Mingw runtime, and if
- -mthreads option is chosen to link in the thread support DLL. */
-static inline int
-__gthread_key_dtor (__gthread_key_t key, void *ptr)
-{
- /* Nothing needed. */
- return 0;
-}
-
static inline int
__gthread_key_delete (__gthread_key_t key)
{
static inline void *
__gthread_getspecific (__gthread_key_t key)
{
- return TlsGetValue (key);
+ DWORD lasterror;
+ void *ptr;
+
+ lasterror = GetLastError ();
+
+ ptr = TlsGetValue (key);
+
+ SetLastError (lasterror);
+
+ return ptr;
}
static inline int
static inline void
__gthread_mutex_init_function (__gthread_mutex_t *mutex)
{
- /* Create unnamed mutex with default security attr and no initial owner. */
- *mutex = CreateMutex (NULL, 0, NULL);
+ mutex->counter = -1;
+ mutex->sema = CreateSemaphore (NULL, 0, 65535, NULL);
}
static inline int
if (__gthread_active_p ())
{
- if (WaitForSingleObject (*mutex, INFINITE) == WAIT_OBJECT_0)
+ if (InterlockedIncrement (&mutex->counter) == 0 ||
+ WaitForSingleObject (mutex->sema, INFINITE) == WAIT_OBJECT_0)
status = 0;
else
- status = 1;
+ {
+ /* WaitForSingleObject returns WAIT_FAILED, and we can only do
+ some best-effort cleanup here. */
+ InterlockedDecrement (&mutex->counter);
+ status = 1;
+ }
}
return status;
}
if (__gthread_active_p ())
{
- if (WaitForSingleObject (*mutex, 0) == WAIT_OBJECT_0)
+ if (__GTHR_W32_InterlockedCompareExchange (&mutex->counter, 0, -1) < 0)
status = 0;
else
status = 1;
__gthread_mutex_unlock (__gthread_mutex_t *mutex)
{
if (__gthread_active_p ())
- return (ReleaseMutex (*mutex) != 0) ? 0 : 1;
- else
- return 0;
+ {
+ 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;
}
-#endif /* not __gthr_win32_h */
+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 */