* 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, write to the
- * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- * Boston, MA 02111-1307, USA.
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
/*
* GLib at ftp://ftp.gtk.org/pub/gtk/.
*/
-/*
- * MT safe
+/* 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"
-#define STRICT
-#define _WIN32_WINDOWS 0x0401 /* to get IsDebuggerPresent */
#include <windows.h>
-#undef STRICT
#include <process.h>
#include <stdlib.h>
#include <stdio.h>
-#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
+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);
+ abort ();
+}
-#define G_MUTEX_SIZE (sizeof (gpointer))
+/* Starting with Vista and Windows 2008, we have access to the
+ * CONDITION_VARIABLE and SRWLock primatives on Windows, which are
+ * pretty reasonable approximations of the primatives 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.
+ *
+ * Unfortunately, Windows XP lacks these facilities and GLib still
+ * needs to support Windows XP. Our approach here is as follows:
+ *
+ * - avoid depending on structure declarations at compile-time by
+ * declaring our own GMutex and GCond strutures to be
+ * ABI-compatible with SRWLock and CONDITION_VARIABLE and using
+ * those instead
+ *
+ * - avoid a hard dependency on the symbols used to manipulate these
+ * structures by doing a dynamic lookup of those symbols at
+ * runtime
+ *
+ * - if the symbols are not available, emulate them using other
+ * primatives
+ *
+ * Using this approach also allows us to easily build a GLib that lacks
+ * support for Windows XP or to remove this code entirely when XP is no
+ * longer supported (end of line is currently April 8, 2014).
+ */
+typedef struct
+{
+ void (__stdcall * CallThisOnThreadExit) (void); /* fake */
+
+ void (__stdcall * InitializeSRWLock) (gpointer lock);
+ void (__stdcall * DeleteSRWLock) (gpointer lock); /* fake */
+ void (__stdcall * AcquireSRWLockExclusive) (gpointer lock);
+ BOOLEAN (__stdcall * TryAcquireSRWLockExclusive) (gpointer lock);
+ void (__stdcall * ReleaseSRWLockExclusive) (gpointer lock);
+ void (__stdcall * AcquireSRWLockShared) (gpointer lock);
+ BOOLEAN (__stdcall * TryAcquireSRWLockShared) (gpointer lock);
+ void (__stdcall * ReleaseSRWLockShared) (gpointer lock);
+
+ void (__stdcall * InitializeConditionVariable) (gpointer cond);
+ void (__stdcall * DeleteConditionVariable) (gpointer cond); /* fake */
+ BOOL (__stdcall * SleepConditionVariableSRW) (gpointer cond,
+ gpointer lock,
+ DWORD timeout,
+ ULONG flags);
+ void (__stdcall * WakeAllConditionVariable) (gpointer cond);
+ void (__stdcall * WakeConditionVariable) (gpointer cond);
+} GThreadImplVtable;
+
+static GThreadImplVtable g_thread_impl_vtable;
+
+/* {{{1 GMutex */
+void
+g_mutex_init (GMutex *mutex)
+{
+ g_thread_impl_vtable.InitializeSRWLock (mutex);
+}
-static DWORD g_thread_self_tls;
-static DWORD g_private_tls;
-static DWORD g_cond_event_tls;
-static CRITICAL_SECTION g_thread_global_spinlock;
+void
+g_mutex_clear (GMutex *mutex)
+{
+ if (g_thread_impl_vtable.DeleteSRWLock != NULL)
+ g_thread_impl_vtable.DeleteSRWLock (mutex);
+}
-typedef BOOL (__stdcall *GTryEnterCriticalSectionFunc) (CRITICAL_SECTION *);
+void
+g_mutex_lock (GMutex *mutex)
+{
+ g_thread_impl_vtable.AcquireSRWLockExclusive (mutex);
+}
-/* As noted in the docs, GPrivate is a limited resource, here we take
- * a rather low maximum to save memory, use GStaticPrivate instead. */
-#define G_PRIVATE_MAX 100
+gboolean
+g_mutex_trylock (GMutex *mutex)
+{
+ return g_thread_impl_vtable.TryAcquireSRWLockExclusive (mutex);
+}
-static GDestroyNotify g_private_destructors[G_PRIVATE_MAX];
+void
+g_mutex_unlock (GMutex *mutex)
+{
+ g_thread_impl_vtable.ReleaseSRWLockExclusive (mutex);
+}
-static guint g_private_next = 0;
+/* {{{1 GRecMutex */
-typedef struct _GThreadData GThreadData;
-struct _GThreadData
+static CRITICAL_SECTION *
+g_rec_mutex_impl_new (void)
{
- GThreadFunc func;
- gpointer data;
- HANDLE thread;
- gboolean joinable;
-};
+ CRITICAL_SECTION *cs;
+
+ cs = g_slice_new (CRITICAL_SECTION);
+ InitializeCriticalSection (cs);
+
+ return cs;
+}
-struct _GCond
+static void
+g_rec_mutex_impl_free (CRITICAL_SECTION *cs)
{
- GPtrArray *array;
- CRITICAL_SECTION lock;
-};
+ DeleteCriticalSection (cs);
+ g_slice_free (CRITICAL_SECTION, cs);
+}
-static GMutex *
-g_mutex_new_win32_impl (void)
+static CRITICAL_SECTION *
+g_rec_mutex_get_impl (GRecMutex *mutex)
{
- CRITICAL_SECTION *cs = g_new (CRITICAL_SECTION, 1);
- gpointer *retval = g_new (gpointer, 1);
+ CRITICAL_SECTION *impl = mutex->p;
- InitializeCriticalSection (cs);
- *retval = cs;
- return (GMutex *) retval;
+ 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;
}
-static void
-g_mutex_free_win32_impl (GMutex *mutex)
+void
+g_rec_mutex_init (GRecMutex *mutex)
{
- gpointer *ptr = (gpointer *) mutex;
- CRITICAL_SECTION *cs = (CRITICAL_SECTION *) *ptr;
+ mutex->p = g_rec_mutex_impl_new ();
+}
- DeleteCriticalSection (cs);
- g_free (cs);
- g_free (mutex);
+void
+g_rec_mutex_clear (GRecMutex *mutex)
+{
+ g_rec_mutex_impl_free (mutex->p);
}
-/* NOTE: the functions g_mutex_lock and g_mutex_unlock may not use
- functions from gmem.c and gmessages.c; */
+void
+g_rec_mutex_lock (GRecMutex *mutex)
+{
+ EnterCriticalSection (g_rec_mutex_get_impl (mutex));
+}
-static void
-g_mutex_lock_win32_impl (GMutex *mutex)
+void
+g_rec_mutex_unlock (GRecMutex *mutex)
{
- EnterCriticalSection (*(CRITICAL_SECTION **)mutex);
+ LeaveCriticalSection (mutex->p);
}
-static gboolean
-g_mutex_trylock_win32_impl (GMutex * mutex)
+gboolean
+g_rec_mutex_trylock (GRecMutex *mutex)
{
- return TryEnterCriticalSection (*(CRITICAL_SECTION **)mutex);
+ return TryEnterCriticalSection (g_rec_mutex_get_impl (mutex));
}
-static void
-g_mutex_unlock_win32_impl (GMutex *mutex)
+/* {{{1 GRWLock */
+
+void
+g_rw_lock_init (GRWLock *lock)
{
- LeaveCriticalSection (*(CRITICAL_SECTION **)mutex);
+ g_thread_impl_vtable.InitializeSRWLock (lock);
}
-static GCond *
-g_cond_new_win32_impl (void)
+void
+g_rw_lock_clear (GRWLock *lock)
{
- GCond *retval = g_new (GCond, 1);
+ if (g_thread_impl_vtable.DeleteSRWLock != NULL)
+ g_thread_impl_vtable.DeleteSRWLock (lock);
+}
- retval->array = g_ptr_array_new ();
- InitializeCriticalSection (&retval->lock);
+void
+g_rw_lock_writer_lock (GRWLock *lock)
+{
+ g_thread_impl_vtable.AcquireSRWLockExclusive (lock);
+}
- return retval;
+gboolean
+g_rw_lock_writer_trylock (GRWLock *lock)
+{
+ return g_thread_impl_vtable.TryAcquireSRWLockExclusive (lock);
}
-static void
-g_cond_signal_win32_impl (GCond * cond)
+void
+g_rw_lock_writer_unlock (GRWLock *lock)
{
- EnterCriticalSection (&cond->lock);
+ g_thread_impl_vtable.ReleaseSRWLockExclusive (lock);
+}
- if (cond->array->len > 0)
- {
- SetEvent (g_ptr_array_index (cond->array, 0));
- g_ptr_array_remove_index (cond->array, 0);
- }
+void
+g_rw_lock_reader_lock (GRWLock *lock)
+{
+ g_thread_impl_vtable.AcquireSRWLockShared (lock);
+}
- LeaveCriticalSection (&cond->lock);
+gboolean
+g_rw_lock_reader_trylock (GRWLock *lock)
+{
+ return g_thread_impl_vtable.TryAcquireSRWLockShared (lock);
}
-static void
-g_cond_broadcast_win32_impl (GCond * cond)
+void
+g_rw_lock_reader_unlock (GRWLock *lock)
{
- guint i;
- EnterCriticalSection (&cond->lock);
+ g_thread_impl_vtable.ReleaseSRWLockShared (lock);
+}
- for (i = 0; i < cond->array->len; i++)
- SetEvent (g_ptr_array_index (cond->array, i));
+/* {{{1 GCond */
+void
+g_cond_init (GCond *cond)
+{
+ g_thread_impl_vtable.InitializeConditionVariable (cond);
+}
- g_ptr_array_set_size (cond->array, 0);
- LeaveCriticalSection (&cond->lock);
+void
+g_cond_clear (GCond *cond)
+{
+ if (g_thread_impl_vtable.DeleteConditionVariable)
+ g_thread_impl_vtable.DeleteConditionVariable (cond);
}
-static gboolean
-g_cond_wait_internal (GCond *cond,
- GMutex *entered_mutex,
- gulong milliseconds)
+void
+g_cond_signal (GCond *cond)
+{
+ g_thread_impl_vtable.WakeConditionVariable (cond);
+}
+
+void
+g_cond_broadcast (GCond *cond)
+{
+ g_thread_impl_vtable.WakeAllConditionVariable (cond);
+}
+
+void
+g_cond_wait (GCond *cond,
+ GMutex *entered_mutex)
+{
+ g_thread_impl_vtable.SleepConditionVariableSRW (cond, entered_mutex, INFINITE, 0);
+}
+
+gboolean
+g_cond_wait_until (GCond *cond,
+ GMutex *entered_mutex,
+ gint64 end_time)
+{
+ gint64 span;
+
+ span = end_time - g_get_monotonic_time ();
+
+ if G_UNLIKELY (span < 0)
+ span = 0;
+
+ if G_UNLIKELY (span > G_GINT64_CONSTANT (1000) * G_MAXINT32)
+ span = INFINITE;
+
+ return g_thread_impl_vtable.SleepConditionVariableSRW (cond, entered_mutex, span / 1000, 0);
+}
+
+/* {{{1 GPrivate */
+
+typedef struct _GPrivateDestructor GPrivateDestructor;
+
+struct _GPrivateDestructor
+{
+ DWORD index;
+ GDestroyNotify notify;
+ GPrivateDestructor *next;
+};
+
+static GPrivateDestructor * volatile g_private_destructors;
+static CRITICAL_SECTION g_private_lock;
+
+static DWORD
+g_private_get_impl (GPrivate *key)
{
- gulong retval;
- HANDLE event = TlsGetValue (g_cond_event_tls);
+ DWORD impl = (DWORD) key->p;
- if (!event)
+ if G_UNLIKELY (impl == 0)
{
- win32_check_for_error (event = CreateEvent (0, FALSE, FALSE, NULL));
- TlsSetValue (g_cond_event_tls, event);
+ EnterCriticalSection (&g_private_lock);
+ impl = (DWORD) key->p;
+ if (impl == 0)
+ {
+ GPrivateDestructor *destructor;
+
+ impl = TlsAlloc ();
+
+ if (impl == TLS_OUT_OF_INDEXES)
+ 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_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 (InterlockedCompareExchangePointer (&g_private_destructors, destructor,
+ destructor->next) != destructor->next)
+ g_thread_abort (0, "g_private_get_impl(1)");
+ }
+
+ /* Ditto, due to the unlocked access on the fast path */
+ if (InterlockedCompareExchangePointer (&key->p, impl, NULL) != NULL)
+ g_thread_abort (0, "g_private_get_impl(2)");
+ }
+ LeaveCriticalSection (&g_private_lock);
}
- EnterCriticalSection (&cond->lock);
+ return impl;
+}
- /* The event must not be signaled. Check this */
- g_assert (WaitForSingleObject (event, 0) == WAIT_TIMEOUT);
+gpointer
+g_private_get (GPrivate *key)
+{
+ return TlsGetValue (g_private_get_impl (key));
+}
- g_ptr_array_add (cond->array, event);
- LeaveCriticalSection (&cond->lock);
+void
+g_private_set (GPrivate *key,
+ gpointer value)
+{
+ TlsSetValue (g_private_get_impl (key), value);
+}
- g_mutex_unlock (entered_mutex);
+void
+g_private_replace (GPrivate *key,
+ gpointer value)
+{
+ DWORD impl = g_private_get_impl (key);
+ gpointer old;
- win32_check_for_error (WAIT_FAILED !=
- (retval = WaitForSingleObject (event, milliseconds)));
+ old = TlsGetValue (impl);
+ if (old && key->notify)
+ key->notify (old);
+ TlsSetValue (impl, value);
+}
- g_mutex_lock (entered_mutex);
+/* {{{1 GThread */
- if (retval == WAIT_TIMEOUT)
- {
- EnterCriticalSection (&cond->lock);
- g_ptr_array_remove (cond->array, event);
+#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
- /* In the meantime we could have been signaled, so we must again
- * wait for the signal, this time with no timeout, to reset
- * it. retval is set again to honour the late arrival of the
- * signal */
- win32_check_for_error (WAIT_FAILED !=
- (retval = WaitForSingleObject (event, 0)));
+#define G_MUTEX_SIZE (sizeof (gpointer))
- LeaveCriticalSection (&cond->lock);
- }
+typedef BOOL (__stdcall *GTryEnterCriticalSectionFunc) (CRITICAL_SECTION *);
+
+typedef struct
+{
+ GRealThread thread;
-#ifndef G_DISABLE_ASSERT
- EnterCriticalSection (&cond->lock);
+ GThreadFunc proxy;
+ HANDLE handle;
+} GThreadWin32;
- /* Now event must not be inside the array, check this */
- g_assert (g_ptr_array_remove (cond->array, event) == FALSE);
+void
+g_system_thread_free (GRealThread *thread)
+{
+ GThreadWin32 *wt = (GThreadWin32 *) thread;
- LeaveCriticalSection (&cond->lock);
-#endif /* !G_DISABLE_ASSERT */
+ win32_check_for_error (CloseHandle (wt->handle));
+ g_slice_free (GThreadWin32, wt);
+}
- return retval != WAIT_TIMEOUT;
+void
+g_system_thread_exit (void)
+{
+ _endthreadex (0);
}
-static void
-g_cond_wait_win32_impl (GCond *cond,
- GMutex *entered_mutex)
+static guint __stdcall
+g_thread_win32_proxy (gpointer data)
{
- g_return_if_fail (cond != NULL);
- g_return_if_fail (entered_mutex != NULL);
+ GThreadWin32 *self = data;
+
+ self->proxy (self);
+
+ g_system_thread_exit ();
- g_cond_wait_internal (cond, entered_mutex, INFINITE);
+ g_assert_not_reached ();
+
+ return 0;
}
-static gboolean
-g_cond_timed_wait_win32_impl (GCond *cond,
- GMutex *entered_mutex,
- GTimeVal *abs_time)
+GRealThread *
+g_system_thread_new (GThreadFunc func,
+ gulong stack_size,
+ GError **error)
{
- GTimeVal current_time;
- gulong to_wait;
+ GThreadWin32 *thread;
+ guint ignore;
- g_return_val_if_fail (cond != NULL, FALSE);
- g_return_val_if_fail (entered_mutex != NULL, FALSE);
+ thread = g_slice_new0 (GThreadWin32);
+ thread->proxy = func;
- if (!abs_time)
- to_wait = INFINITE;
- else
+ thread->handle = (HANDLE) _beginthreadex (NULL, stack_size, g_thread_win32_proxy, thread, 0, &ignore);
+
+ if (thread->handle == NULL)
{
- g_get_current_time (¤t_time);
- if (abs_time->tv_sec < current_time.tv_sec ||
- (abs_time->tv_sec == current_time.tv_sec &&
- abs_time->tv_usec <= current_time.tv_usec))
- to_wait = 0;
- else
- to_wait = (abs_time->tv_sec - current_time.tv_sec) * 1000 +
- (abs_time->tv_usec - current_time.tv_usec) / 1000;
+ gchar *win_error = g_win32_error_message (GetLastError ());
+ g_set_error (error, G_THREAD_ERROR, G_THREAD_ERROR_AGAIN,
+ "Error creating thread: %s", win_error);
+ g_free (win_error);
+ g_slice_free (GThreadWin32, thread);
+ return NULL;
}
- return g_cond_wait_internal (cond, entered_mutex, to_wait);
+ return (GRealThread *) thread;
}
-static void
-g_cond_free_win32_impl (GCond * cond)
+void
+g_thread_yield (void)
+{
+ Sleep(0);
+}
+
+void
+g_system_thread_wait (GRealThread *thread)
{
- DeleteCriticalSection (&cond->lock);
- g_ptr_array_free (cond->array, TRUE);
- g_free (cond);
+ GThreadWin32 *wt = (GThreadWin32 *) thread;
+
+ win32_check_for_error (WAIT_FAILED != WaitForSingleObject (wt->handle, INFINITE));
+}
+
+void
+g_system_thread_set_name (const gchar *name)
+{
+ /* FIXME: implement */
}
-static GPrivate *
-g_private_new_win32_impl (GDestroyNotify destructor)
+/* {{{1 SRWLock and CONDITION_VARIABLE emulation (for Windows XP) */
+
+static CRITICAL_SECTION g_thread_xp_lock;
+static DWORD g_thread_xp_waiter_tls;
+
+/* {{{2 GThreadWaiter utility class for CONDITION_VARIABLE emulation */
+typedef struct _GThreadXpWaiter GThreadXpWaiter;
+struct _GThreadXpWaiter
+{
+ HANDLE event;
+ volatile GThreadXpWaiter *next;
+ volatile GThreadXpWaiter **my_owner;
+};
+
+static GThreadXpWaiter *
+g_thread_xp_waiter_get (void)
{
- GPrivate *result;
- EnterCriticalSection (&g_thread_global_spinlock);
- if (g_private_next >= G_PRIVATE_MAX)
+ GThreadXpWaiter *waiter;
+
+ waiter = TlsGetValue (g_thread_xp_waiter_tls);
+
+ if G_UNLIKELY (waiter == NULL)
{
- char buf[100];
- sprintf (buf,
- "Too many GPrivate allocated. Their number is limited to %d.",
- G_PRIVATE_MAX);
- MessageBox (NULL, buf, NULL, MB_ICONERROR|MB_SETFOREGROUND);
- if (IsDebuggerPresent ())
- G_BREAKPOINT ();
- abort ();
+ waiter = malloc (sizeof (GThreadXpWaiter));
+ if (waiter == NULL)
+ g_thread_abort (GetLastError (), "malloc");
+ waiter->event = CreateEvent (0, FALSE, FALSE, NULL);
+ if (waiter->event == NULL)
+ g_thread_abort (GetLastError (), "CreateEvent");
+ waiter->my_owner = NULL;
+
+ TlsSetValue (g_thread_xp_waiter_tls, waiter);
}
- g_private_destructors[g_private_next] = destructor;
- result = GUINT_TO_POINTER (g_private_next);
- g_private_next++;
- LeaveCriticalSection (&g_thread_global_spinlock);
- return result;
+ return waiter;
}
-/* NOTE: the functions g_private_get and g_private_set may not use
- functions from gmem.c and gmessages.c */
-
-static void
-g_private_set_win32_impl (GPrivate * private_key, gpointer value)
+static void __stdcall
+g_thread_xp_CallThisOnThreadExit (void)
{
- gpointer* array = TlsGetValue (g_private_tls);
- guint index = GPOINTER_TO_UINT (private_key);
+ GThreadXpWaiter *waiter;
- if (index >= G_PRIVATE_MAX)
- return;
+ waiter = TlsGetValue (g_thread_xp_waiter_tls);
- if (!array)
+ if (waiter != NULL)
{
- array = (gpointer*) calloc (G_PRIVATE_MAX, sizeof (gpointer));
- TlsSetValue (g_private_tls, array);
+ TlsSetValue (g_thread_xp_waiter_tls, NULL);
+ CloseHandle (waiter->event);
+ free (waiter);
}
+}
- array[index] = value;
+/* {{{2 SRWLock emulation */
+typedef struct
+{
+ CRITICAL_SECTION writer_lock;
+ gboolean ever_shared; /* protected by writer_lock */
+ gboolean writer_locked; /* protected by writer_lock */
+
+ /* below is only ever touched if ever_shared becomes true */
+ CRITICAL_SECTION atomicity;
+ GThreadXpWaiter *queued_writer; /* protected by atomicity lock */
+ gint num_readers; /* protected by atomicity lock */
+} GThreadSRWLock;
+
+static void __stdcall
+g_thread_xp_InitializeSRWLock (gpointer mutex)
+{
+ *(GThreadSRWLock * volatile *) mutex = NULL;
}
-static gpointer
-g_private_get_win32_impl (GPrivate * private_key)
+static void __stdcall
+g_thread_xp_DeleteSRWLock (gpointer mutex)
{
- gpointer* array = TlsGetValue (g_private_tls);
- guint index = GPOINTER_TO_UINT (private_key);
+ GThreadSRWLock *lock = *(GThreadSRWLock * volatile *) mutex;
- if (index >= G_PRIVATE_MAX || !array)
- return NULL;
+ if (lock)
+ {
+ if (lock->ever_shared)
+ DeleteCriticalSection (&lock->atomicity);
- return array[index];
+ DeleteCriticalSection (&lock->writer_lock);
+ free (lock);
+ }
}
-static void
-g_thread_set_priority_win32_impl (gpointer thread, GThreadPriority priority)
+static GThreadSRWLock * __stdcall
+g_thread_xp_get_srwlock (GThreadSRWLock * volatile *lock)
{
- GThreadData *target = *(GThreadData **)thread;
- gint native_prio;
+ GThreadSRWLock *result;
- switch (priority)
+ /* It looks like we're missing some barriers here, but this code only
+ * ever runs on Windows XP, which in turn only ever runs on hardware
+ * with a relatively rigid memory model. The 'volatile' will take
+ * care of the compiler.
+ */
+ result = *lock;
+
+ if G_UNLIKELY (result == NULL)
{
- case G_THREAD_PRIORITY_LOW:
- native_prio = THREAD_PRIORITY_BELOW_NORMAL;
- break;
+ EnterCriticalSection (&g_thread_xp_lock);
- case G_THREAD_PRIORITY_NORMAL:
- native_prio = THREAD_PRIORITY_NORMAL;
- break;
+ /* Check again */
+ result = *lock;
+ if (result == NULL)
+ {
+ result = malloc (sizeof (GThreadSRWLock));
- case G_THREAD_PRIORITY_HIGH:
- native_prio = THREAD_PRIORITY_ABOVE_NORMAL;
- break;
+ if (result == NULL)
+ g_thread_abort (errno, "malloc");
- case G_THREAD_PRIORITY_URGENT:
- native_prio = THREAD_PRIORITY_HIGHEST;
- break;
+ InitializeCriticalSection (&result->writer_lock);
+ result->writer_locked = FALSE;
+ result->ever_shared = FALSE;
+ *lock = result;
+ }
- default:
- g_return_if_reached ();
+ LeaveCriticalSection (&g_thread_xp_lock);
}
- win32_check_for_error (SetThreadPriority (target->thread, native_prio));
+ return result;
}
-static void
-g_thread_self_win32_impl (gpointer thread)
+static void __stdcall
+g_thread_xp_AcquireSRWLockExclusive (gpointer mutex)
{
- GThreadData *self = TlsGetValue (g_thread_self_tls);
+ GThreadSRWLock *lock = g_thread_xp_get_srwlock (mutex);
+
+ EnterCriticalSection (&lock->writer_lock);
- if (!self)
+ /* CRITICAL_SECTION is reentrant, but SRWLock is not.
+ * Detect the deadlock that would occur on later Windows version.
+ */
+ g_assert (!lock->writer_locked);
+ lock->writer_locked = TRUE;
+
+ if (lock->ever_shared)
{
- /* This should only happen for the main thread! */
- HANDLE handle = GetCurrentThread ();
- HANDLE process = GetCurrentProcess ();
- self = g_new (GThreadData, 1);
- win32_check_for_error (DuplicateHandle (process, handle, process,
- &self->thread, 0, FALSE,
- DUPLICATE_SAME_ACCESS));
- win32_check_for_error (TlsSetValue (g_thread_self_tls, self));
- self->func = NULL;
- self->data = NULL;
- self->joinable = FALSE;
- }
+ GThreadXpWaiter *waiter = NULL;
- *(GThreadData **)thread = self;
+ EnterCriticalSection (&lock->atomicity);
+ if (lock->num_readers > 0)
+ lock->queued_writer = waiter = g_thread_xp_waiter_get ();
+ LeaveCriticalSection (&lock->atomicity);
+
+ if (waiter != NULL)
+ WaitForSingleObject (waiter->event, INFINITE);
+
+ lock->queued_writer = NULL;
+ }
}
-static void
-g_thread_exit_win32_impl (void)
+static BOOLEAN __stdcall
+g_thread_xp_TryAcquireSRWLockExclusive (gpointer mutex)
{
- GThreadData *self = TlsGetValue (g_thread_self_tls);
- guint i, private_max;
- gpointer *array = TlsGetValue (g_private_tls);
- HANDLE event = TlsGetValue (g_cond_event_tls);
+ GThreadSRWLock *lock = g_thread_xp_get_srwlock (mutex);
- EnterCriticalSection (&g_thread_global_spinlock);
- private_max = g_private_next;
- LeaveCriticalSection (&g_thread_global_spinlock);
+ if (!TryEnterCriticalSection (&lock->writer_lock))
+ return FALSE;
- if (array)
+ /* CRITICAL_SECTION is reentrant, but SRWLock is not.
+ * Ensure that this properly returns FALSE (as SRWLock would).
+ */
+ if G_UNLIKELY (lock->writer_locked)
{
- gboolean some_data_non_null;
+ LeaveCriticalSection (&lock->writer_lock);
+ return FALSE;
+ }
- do {
- some_data_non_null = FALSE;
- for (i = 0; i < private_max; i++)
- {
- GDestroyNotify destructor = g_private_destructors[i];
- GDestroyNotify data = array[i];
+ lock->writer_locked = TRUE;
- if (data)
- some_data_non_null = TRUE;
+ if (lock->ever_shared)
+ {
+ gboolean available;
- array[i] = NULL;
+ EnterCriticalSection (&lock->atomicity);
+ available = lock->num_readers == 0;
+ LeaveCriticalSection (&lock->atomicity);
- if (destructor && data)
- destructor (data);
- }
- } while (some_data_non_null);
+ if (!available)
+ {
+ LeaveCriticalSection (&lock->writer_lock);
+ return FALSE;
+ }
+ }
- free (array);
+ return TRUE;
+}
- win32_check_for_error (TlsSetValue (g_private_tls, NULL));
- }
+static void __stdcall
+g_thread_xp_ReleaseSRWLockExclusive (gpointer mutex)
+{
+ GThreadSRWLock *lock = *(GThreadSRWLock * volatile *) mutex;
+
+ lock->writer_locked = FALSE;
- if (self)
+ /* We need this until we fix some weird parts of GLib that try to
+ * unlock freshly-allocated mutexes.
+ */
+ if (lock != NULL)
+ LeaveCriticalSection (&lock->writer_lock);
+}
+
+static void
+g_thread_xp_srwlock_become_reader (GThreadSRWLock *lock)
+{
+ if G_UNLIKELY (!lock->ever_shared)
{
- if (!self->joinable)
- {
- win32_check_for_error (CloseHandle (self->thread));
- g_free (self);
- }
- win32_check_for_error (TlsSetValue (g_thread_self_tls, NULL));
+ InitializeCriticalSection (&lock->atomicity);
+ lock->queued_writer = NULL;
+ lock->num_readers = 0;
+
+ lock->ever_shared = TRUE;
}
- if (event)
+ EnterCriticalSection (&lock->atomicity);
+ lock->num_readers++;
+ LeaveCriticalSection (&lock->atomicity);
+}
+
+static void __stdcall
+g_thread_xp_AcquireSRWLockShared (gpointer mutex)
+{
+ GThreadSRWLock *lock = g_thread_xp_get_srwlock (mutex);
+
+ EnterCriticalSection (&lock->writer_lock);
+
+ /* See g_thread_xp_AcquireSRWLockExclusive */
+ g_assert (!lock->writer_locked);
+
+ g_thread_xp_srwlock_become_reader (lock);
+
+ LeaveCriticalSection (&lock->writer_lock);
+}
+
+static BOOLEAN __stdcall
+g_thread_xp_TryAcquireSRWLockShared (gpointer mutex)
+{
+ GThreadSRWLock *lock = g_thread_xp_get_srwlock (mutex);
+
+ if (!TryEnterCriticalSection (&lock->writer_lock))
+ return FALSE;
+
+ /* See g_thread_xp_AcquireSRWLockExclusive */
+ if G_UNLIKELY (lock->writer_locked)
{
- CloseHandle (event);
- win32_check_for_error (TlsSetValue (g_cond_event_tls, NULL));
+ LeaveCriticalSection (&lock->writer_lock);
+ return FALSE;
}
- _endthreadex (0);
+ g_thread_xp_srwlock_become_reader (lock);
+
+ LeaveCriticalSection (&lock->writer_lock);
+
+ return TRUE;
}
-static guint __stdcall
-g_thread_proxy (gpointer data)
+static void __stdcall
+g_thread_xp_ReleaseSRWLockShared (gpointer mutex)
{
- GThreadData *self = (GThreadData*) data;
+ GThreadSRWLock *lock = g_thread_xp_get_srwlock (mutex);
- win32_check_for_error (TlsSetValue (g_thread_self_tls, self));
+ EnterCriticalSection (&lock->atomicity);
- self->func (self->data);
+ lock->num_readers--;
- g_thread_exit_win32_impl ();
+ if (lock->num_readers == 0 && lock->queued_writer)
+ SetEvent (lock->queued_writer->event);
- g_assert_not_reached ();
+ LeaveCriticalSection (&lock->atomicity);
+}
- return 0;
+/* {{{2 CONDITION_VARIABLE emulation */
+typedef struct
+{
+ volatile GThreadXpWaiter *first;
+ volatile GThreadXpWaiter **last_ptr;
+} GThreadXpCONDITION_VARIABLE;
+
+static void __stdcall
+g_thread_xp_InitializeConditionVariable (gpointer cond)
+{
+ *(GThreadXpCONDITION_VARIABLE * volatile *) cond = NULL;
}
-static void
-g_thread_create_win32_impl (GThreadFunc func,
- gpointer data,
- gulong stack_size,
- gboolean joinable,
- gboolean bound,
- GThreadPriority priority,
- gpointer thread,
- GError **error)
+static void __stdcall
+g_thread_xp_DeleteConditionVariable (gpointer cond)
{
- guint ignore;
- GThreadData *retval;
+ GThreadXpCONDITION_VARIABLE *cv = *(GThreadXpCONDITION_VARIABLE * volatile *) cond;
+
+ if (cv)
+ free (cv);
+}
+
+static GThreadXpCONDITION_VARIABLE * __stdcall
+g_thread_xp_get_condition_variable (GThreadXpCONDITION_VARIABLE * volatile *cond)
+{
+ GThreadXpCONDITION_VARIABLE *result;
+
+ /* It looks like we're missing some barriers here, but this code only
+ * ever runs on Windows XP, which in turn only ever runs on hardware
+ * with a relatively rigid memory model. The 'volatile' will take
+ * care of the compiler.
+ */
+ result = *cond;
- g_return_if_fail (func);
- g_return_if_fail (priority >= G_THREAD_PRIORITY_LOW);
- g_return_if_fail (priority <= G_THREAD_PRIORITY_URGENT);
+ if G_UNLIKELY (result == NULL)
+ {
+ result = malloc (sizeof (GThreadXpCONDITION_VARIABLE));
+
+ if (result == NULL)
+ g_thread_abort (errno, "malloc");
+
+ result->first = NULL;
+ result->last_ptr = &result->first;
+
+ if (InterlockedCompareExchangePointer (cond, result, NULL) != NULL)
+ {
+ free (result);
+ result = *cond;
+ }
+ }
+
+ return result;
+}
+
+static BOOL __stdcall
+g_thread_xp_SleepConditionVariableSRW (gpointer cond,
+ gpointer mutex,
+ DWORD timeout,
+ ULONG flags)
+{
+ GThreadXpCONDITION_VARIABLE *cv = g_thread_xp_get_condition_variable (cond);
+ GThreadXpWaiter *waiter = g_thread_xp_waiter_get ();
+ DWORD status;
+
+ waiter->next = NULL;
- retval = g_new(GThreadData, 1);
- retval->func = func;
- retval->data = data;
+ EnterCriticalSection (&g_thread_xp_lock);
+ waiter->my_owner = cv->last_ptr;
+ *cv->last_ptr = waiter;
+ cv->last_ptr = &waiter->next;
+ LeaveCriticalSection (&g_thread_xp_lock);
- retval->joinable = joinable;
+ g_mutex_unlock (mutex);
+ status = WaitForSingleObject (waiter->event, timeout);
- retval->thread = (HANDLE) _beginthreadex (NULL, stack_size, g_thread_proxy,
- retval, 0, &ignore);
+ if (status != WAIT_TIMEOUT && status != WAIT_OBJECT_0)
+ g_thread_abort (GetLastError (), "WaitForSingleObject");
+ g_mutex_lock (mutex);
- if (retval->thread == NULL)
+ if (status == WAIT_TIMEOUT)
{
- gchar *win_error = g_win32_error_message (GetLastError ());
- g_set_error (error, G_THREAD_ERROR, G_THREAD_ERROR_AGAIN,
- "Error creating thread: %s", win_error);
- g_free (retval);
- g_free (win_error);
- return;
+ EnterCriticalSection (&g_thread_xp_lock);
+ if (waiter->my_owner)
+ {
+ if (waiter->next)
+ waiter->next->my_owner = waiter->my_owner;
+ else
+ cv->last_ptr = waiter->my_owner;
+ *waiter->my_owner = waiter->next;
+ waiter->my_owner = NULL;
+ }
+ LeaveCriticalSection (&g_thread_xp_lock);
+ }
+
+ return status == WAIT_OBJECT_0;
+}
+
+static void __stdcall
+g_thread_xp_WakeConditionVariable (gpointer cond)
+{
+ GThreadXpCONDITION_VARIABLE *cv = g_thread_xp_get_condition_variable (cond);
+ volatile GThreadXpWaiter *waiter;
+
+ EnterCriticalSection (&g_thread_xp_lock);
+
+ waiter = cv->first;
+ if (waiter != NULL)
+ {
+ waiter->my_owner = NULL;
+ cv->first = waiter->next;
+ if (cv->first != NULL)
+ cv->first->my_owner = &cv->first;
+ else
+ cv->last_ptr = &cv->first;
}
- *(GThreadData **)thread = retval;
+ if (waiter != NULL)
+ SetEvent (waiter->event);
- g_thread_set_priority_win32_impl (thread, priority);
+ LeaveCriticalSection (&g_thread_xp_lock);
}
-static void
-g_thread_yield_win32_impl (void)
+static void __stdcall
+g_thread_xp_WakeAllConditionVariable (gpointer cond)
{
- Sleep(0);
+ GThreadXpCONDITION_VARIABLE *cv = g_thread_xp_get_condition_variable (cond);
+ volatile GThreadXpWaiter *waiter;
+
+ EnterCriticalSection (&g_thread_xp_lock);
+
+ waiter = cv->first;
+ cv->first = NULL;
+ cv->last_ptr = &cv->first;
+
+ while (waiter != NULL)
+ {
+ volatile GThreadXpWaiter *next;
+
+ next = waiter->next;
+ SetEvent (waiter->event);
+ waiter->my_owner = NULL;
+ waiter = next;
+ }
+
+ LeaveCriticalSection (&g_thread_xp_lock);
}
+/* {{{2 XP Setup */
static void
-g_thread_join_win32_impl (gpointer thread)
-{
- GThreadData *target = *(GThreadData **)thread;
-
- g_return_if_fail (target->joinable);
-
- win32_check_for_error (WAIT_FAILED !=
- WaitForSingleObject (target->thread, INFINITE));
-
- win32_check_for_error (CloseHandle (target->thread));
- g_free (target);
-}
-
-GThreadFunctions g_thread_functions_for_glib_use =
-{
- g_mutex_new_win32_impl, /* mutex */
- g_mutex_lock_win32_impl,
- g_mutex_trylock_win32_impl,
- g_mutex_unlock_win32_impl,
- g_mutex_free_win32_impl,
- g_cond_new_win32_impl, /* condition */
- g_cond_signal_win32_impl,
- g_cond_broadcast_win32_impl,
- g_cond_wait_win32_impl,
- g_cond_timed_wait_win32_impl,
- g_cond_free_win32_impl,
- g_private_new_win32_impl, /* private thread data */
- g_private_get_win32_impl,
- g_private_set_win32_impl,
- g_thread_create_win32_impl, /* thread */
- g_thread_yield_win32_impl,
- g_thread_join_win32_impl,
- g_thread_exit_win32_impl,
- g_thread_set_priority_win32_impl,
- g_thread_self_win32_impl,
- NULL /* no equal function necessary */
-};
+g_thread_xp_init (void)
+{
+ static const GThreadImplVtable g_thread_xp_impl_vtable = {
+ g_thread_xp_CallThisOnThreadExit,
+ g_thread_xp_InitializeSRWLock,
+ g_thread_xp_DeleteSRWLock,
+ g_thread_xp_AcquireSRWLockExclusive,
+ g_thread_xp_TryAcquireSRWLockExclusive,
+ g_thread_xp_ReleaseSRWLockExclusive,
+ g_thread_xp_AcquireSRWLockShared,
+ g_thread_xp_TryAcquireSRWLockShared,
+ g_thread_xp_ReleaseSRWLockShared,
+ g_thread_xp_InitializeConditionVariable,
+ g_thread_xp_DeleteConditionVariable,
+ g_thread_xp_SleepConditionVariableSRW,
+ g_thread_xp_WakeAllConditionVariable,
+ g_thread_xp_WakeConditionVariable
+ };
+
+ InitializeCriticalSection (&g_thread_xp_lock);
+ g_thread_xp_waiter_tls = TlsAlloc ();
+
+ g_thread_impl_vtable = g_thread_xp_impl_vtable;
+}
+
+/* {{{1 Epilogue */
+
+static gboolean
+g_thread_lookup_native_funcs (void)
+{
+ GThreadImplVtable native_vtable = { 0, };
+ HMODULE kernel32;
+
+ kernel32 = GetModuleHandle ("KERNEL32.DLL");
+
+ if (kernel32 == NULL)
+ return FALSE;
+
+#define GET_FUNC(name) if ((native_vtable.name = (void *) GetProcAddress (kernel32, #name)) == NULL) return FALSE
+ GET_FUNC(InitializeSRWLock);
+ GET_FUNC(AcquireSRWLockExclusive);
+ GET_FUNC(TryAcquireSRWLockExclusive);
+ GET_FUNC(ReleaseSRWLockExclusive);
+ GET_FUNC(AcquireSRWLockShared);
+ GET_FUNC(TryAcquireSRWLockShared);
+ GET_FUNC(ReleaseSRWLockShared);
+
+ GET_FUNC(InitializeConditionVariable);
+ GET_FUNC(SleepConditionVariableSRW);
+ GET_FUNC(WakeAllConditionVariable);
+ GET_FUNC(WakeConditionVariable);
+#undef GET_FUNC
+
+ g_thread_impl_vtable = native_vtable;
+
+ return TRUE;
+}
void
-_g_thread_impl_init (void)
+g_thread_win32_init (void)
{
- static gboolean beenhere = FALSE;
+ if (!g_thread_lookup_native_funcs ())
+ g_thread_xp_init ();
- if (beenhere)
- return;
+ InitializeCriticalSection (&g_private_lock);
+}
- beenhere = TRUE;
+void
+g_thread_win32_thread_detach (void)
+{
+ gboolean dtors_called;
- win32_check_for_error (TLS_OUT_OF_INDEXES !=
- (g_thread_self_tls = TlsAlloc ()));
- win32_check_for_error (TLS_OUT_OF_INDEXES !=
- (g_private_tls = TlsAlloc ()));
- win32_check_for_error (TLS_OUT_OF_INDEXES !=
- (g_cond_event_tls = TlsAlloc ()));
- InitializeCriticalSection (&g_thread_global_spinlock);
+ 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_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);
+
+ if (g_thread_impl_vtable.CallThisOnThreadExit)
+ g_thread_impl_vtable.CallThisOnThreadExit ();
}
+
+/* vim:set foldmethod=marker: */
projects / platform / upstream / glib.git / blobdiff