# include <mmsystem.h>
#endif
-static vlc_threadvar_t cancel_key;
+static vlc_threadvar_t thread_key;
/**
- * Per-thread cancellation data
+ * Per-thread data
*/
-typedef struct vlc_cancel_t
+struct vlc_thread
{
- vlc_cleanup_t *cleaners;
+ HANDLE id;
#ifdef UNDER_CE
HANDLE cancel_event;
#endif
+
+ bool detached;
bool killable;
bool killed;
-} vlc_cancel_t;
+ vlc_cleanup_t *cleaners;
-#ifndef UNDER_CE
-# define VLC_CANCEL_INIT { NULL, true, false }
-#else
-# define VLC_CANCEL_INIT { NULL, NULL, true, false }
-#endif
+ void *(*entry) (void *);
+ void *data;
+};
#ifdef UNDER_CE
static void CALLBACK vlc_cancel_self (ULONG_PTR dummy);
static DWORD vlc_cancelable_wait (DWORD count, const HANDLE *handles,
DWORD delay)
{
- vlc_cancel_t *nfo = vlc_threadvar_get (cancel_key);
- if (nfo == NULL)
+ struct vlc_thread *th = vlc_threadvar_get (thread_key);
+ if (th == NULL)
{
/* Main thread - cannot be cancelled anyway */
return WaitForMultipleObjects (count, handles, FALSE, delay);
}
HANDLE new_handles[count + 1];
memcpy(new_handles, handles, count * sizeof(HANDLE));
- new_handles[count] = nfo->cancel_event;
+ new_handles[count] = th->cancel_event;
DWORD result = WaitForMultipleObjects (count + 1, new_handles, FALSE,
delay);
if (result == WAIT_OBJECT_0 + count)
{
- vlc_cancel_self (NULL);
+ vlc_cancel_self ((uintptr_t)th);
return WAIT_IO_COMPLETION;
}
else
case DLL_PROCESS_ATTACH:
vlc_mutex_init (&super_mutex);
vlc_cond_init (&super_variable);
- vlc_threadvar_create (&cancel_key, NULL);
+ vlc_threadvar_create (&thread_key, NULL);
break;
case DLL_PROCESS_DETACH:
- vlc_threadvar_delete( &cancel_key );
+ vlc_threadvar_delete (&thread_key);
vlc_cond_destroy (&super_variable);
vlc_mutex_destroy (&super_mutex);
break;
vlc_cond_init (&lock->read_wait);
vlc_cond_init (&lock->write_wait);
lock->readers = 0; /* active readers */
- lock->writers = 0; /* waiting or active writers */
+ lock->writers = 0; /* waiting writers */
lock->writer = 0; /* ID of active writer */
}
-/**
- * Destroys an initialized unused read/write lock.
- */
void vlc_rwlock_destroy (vlc_rwlock_t *lock)
{
vlc_cond_destroy (&lock->read_wait);
vlc_mutex_destroy (&lock->mutex);
}
-/**
- * Acquires a read/write lock for reading. Recursion is allowed.
- */
void vlc_rwlock_rdlock (vlc_rwlock_t *lock)
{
vlc_mutex_lock (&lock->mutex);
+ /* Recursive read-locking is allowed. With the infos available:
+ * - the loosest possible condition (no active writer) is:
+ * (lock->writer != 0)
+ * - the strictest possible condition is:
+ * (lock->writer != 0 || (lock->readers == 0 && lock->writers > 0))
+ * or (lock->readers == 0 && (lock->writer != 0 || lock->writers > 0))
+ */
while (lock->writer != 0)
+ {
+ assert (lock->readers == 0);
vlc_cond_wait (&lock->read_wait, &lock->mutex);
- if (lock->readers == ULONG_MAX)
+ }
+ if (unlikely(lock->readers == ULONG_MAX))
abort ();
lock->readers++;
vlc_mutex_unlock (&lock->mutex);
}
-/**
- * Acquires a read/write lock for writing. Recursion is not allowed.
- */
+static void vlc_rwlock_rdunlock (vlc_rwlock_t *lock)
+{
+ vlc_mutex_lock (&lock->mutex);
+ assert (lock->readers > 0);
+
+ /* If there are no readers left, wake up a writer. */
+ if (--lock->readers == 0 && lock->writers > 0)
+ vlc_cond_signal (&lock->write_wait);
+ vlc_mutex_unlock (&lock->mutex);
+}
+
void vlc_rwlock_wrlock (vlc_rwlock_t *lock)
{
vlc_mutex_lock (&lock->mutex);
- if (lock->writers == ULONG_MAX)
+ if (unlikely(lock->writers == ULONG_MAX))
abort ();
lock->writers++;
+ /* Wait until nobody owns the lock in either way. */
while ((lock->readers > 0) || (lock->writer != 0))
vlc_cond_wait (&lock->write_wait, &lock->mutex);
lock->writers--;
+ assert (lock->writer == 0);
lock->writer = GetCurrentThreadId ();
vlc_mutex_unlock (&lock->mutex);
}
-/**
- * Releases a read/write lock.
- */
-void vlc_rwlock_unlock (vlc_rwlock_t *lock)
+static void vlc_rwlock_wrunlock (vlc_rwlock_t *lock)
{
vlc_mutex_lock (&lock->mutex);
- if (lock->readers > 0)
- lock->readers--; /* Read unlock */
- else
- lock->writer = 0; /* Write unlock */
+ assert (lock->writer == GetCurrentThreadId ());
+ assert (lock->readers == 0);
+ lock->writer = 0; /* Write unlock */
+ /* Let reader and writer compete. Scheduler decides who wins. */
if (lock->writers > 0)
- {
- if (lock->readers == 0)
- vlc_cond_signal (&lock->write_wait);
- }
- else
- vlc_cond_broadcast (&lock->read_wait);
+ vlc_cond_signal (&lock->write_wait);
+ vlc_cond_broadcast (&lock->read_wait);
vlc_mutex_unlock (&lock->mutex);
}
+void vlc_rwlock_unlock (vlc_rwlock_t *lock)
+{
+ /* Note: If the lock is held for reading, lock->writer is nul.
+ * If the lock is held for writing, only this thread can store a value to
+ * lock->writer. Either way, lock->writer is safe to fetch here. */
+ if (lock->writer != 0)
+ vlc_rwlock_wrunlock (lock);
+ else
+ vlc_rwlock_rdunlock (lock);
+}
+
/*** Thread-specific variables (TLS) ***/
struct vlc_threadvar
{
var->id = TlsAlloc();
if (var->id == TLS_OUT_OF_INDEXES)
+ {
+ free (var);
return EAGAIN;
+ }
var->destroy = destr;
var->next = NULL;
*p_tls = var;
return TlsGetValue (key->id);
}
-static void vlc_threadvar_cleanup (void)
+/*** Threads ***/
+void vlc_threads_setup (libvlc_int_t *p_libvlc)
+{
+ (void) p_libvlc;
+}
+
+static void vlc_thread_cleanup (struct vlc_thread *th)
{
vlc_threadvar_t key;
for (key = vlc_threadvar_last; key != NULL; key = key->prev)
{
void *value = vlc_threadvar_get (key);
- if (value != NULL)
+ if (value != NULL && key->destroy != NULL)
{
vlc_mutex_unlock (&super_mutex);
vlc_threadvar_set (key, NULL);
}
}
vlc_mutex_unlock (&super_mutex);
-}
-
-/*** Threads ***/
-void vlc_threads_setup (libvlc_int_t *p_libvlc)
-{
- (void) p_libvlc;
-}
-
-struct vlc_entry_data
-{
- void * (*func) (void *);
- void * data;
- vlc_sem_t ready;
+ if (th->detached)
+ {
+ CloseHandle (th->id);
#ifdef UNDER_CE
- HANDLE cancel_event;
+ CloseHandle (th->cancel_event);
#endif
-};
+ free (th);
+ }
+}
static unsigned __stdcall vlc_entry (void *p)
{
- struct vlc_entry_data *entry = p;
- vlc_cancel_t cancel_data = VLC_CANCEL_INIT;
- void *(*func) (void *) = entry->func;
- void *data = entry->data;
+ struct vlc_thread *th = p;
-#ifdef UNDER_CE
- cancel_data.cancel_event = entry->cancel_event;
-#endif
- vlc_threadvar_set (cancel_key, &cancel_data);
- vlc_sem_post (&entry->ready);
- func (data);
- vlc_threadvar_cleanup ();
+ vlc_threadvar_set (thread_key, th);
+ th->killable = true;
+ th->data = th->entry (th->data);
+ vlc_thread_cleanup (th);
return 0;
}
-int vlc_clone (vlc_thread_t *p_handle, void * (*entry) (void *), void *data,
- int priority)
+static int vlc_clone_attr (vlc_thread_t *p_handle, bool detached,
+ void *(*entry) (void *), void *data, int priority)
{
- int err = ENOMEM;
- HANDLE hThread;
-
- struct vlc_entry_data *entry_data = malloc (sizeof (*entry_data));
- if (entry_data == NULL)
+ struct vlc_thread *th = malloc (sizeof (*th));
+ if (unlikely(th == NULL))
return ENOMEM;
- entry_data->func = entry;
- entry_data->data = data;
- vlc_sem_init (&entry_data->ready, 0);
+ th->entry = entry;
+ th->data = data;
+ th->detached = detached;
+ th->killable = false; /* not until vlc_entry() ! */
+ th->killed = false;
+ th->cleaners = NULL;
+ HANDLE hThread;
#ifndef UNDER_CE
/* When using the MSVCRT C library you have to use the _beginthreadex
* function instead of CreateThread, otherwise you'll end up with
* memory leaks and the signal functions not working (see Microsoft
* Knowledge Base, article 104641) */
hThread = (HANDLE)(uintptr_t)
- _beginthreadex (NULL, 0, vlc_entry, entry_data, CREATE_SUSPENDED, NULL);
- if (! hThread)
+ _beginthreadex (NULL, 0, vlc_entry, th, CREATE_SUSPENDED, NULL);
+ if (hThread == NULL)
{
- err = errno;
- goto error;
+ int err = errno;
+ free (th);
+ return err;
}
- *p_handle = hThread;
-
#else
- vlc_thread_t th = malloc (sizeof (*th));
- if (th == NULL)
- goto error;
th->cancel_event = CreateEvent (NULL, FALSE, FALSE, NULL);
if (th->cancel_event == NULL)
{
free (th);
- goto error;
+ return ENOMEM;
}
- entry_data->cancel_event = th->cancel_event;
/* Not sure if CREATE_SUSPENDED + ResumeThread() is any useful on WinCE.
* Thread handles act up, too. */
- th->handle = CreateThread (NULL, 128*1024, vlc_entry, entry_data,
- CREATE_SUSPENDED, NULL);
- if (th->handle == NULL)
+ hThread = CreateThread (NULL, 128*1024, vlc_entry, th,
+ CREATE_SUSPENDED, NULL);
+ if (hThread == NULL)
{
CloseHandle (th->cancel_event);
free (th);
- goto error;
+ return ENOMEM;
}
- *p_handle = th;
- hThread = th->handle;
-
#endif
+ /* Thread is suspended, so we can safely set th->id */
+ th->id = hThread;
+ if (p_handle != NULL)
+ *p_handle = th;
- ResumeThread (hThread);
if (priority)
SetThreadPriority (hThread, priority);
- /* Prevent cancellation until cancel_data is initialized. */
- /* XXX: This could be postponed to vlc_cancel() or avoided completely by
- * passing the "right" pointer to vlc_cancel_self(). */
- vlc_sem_wait (&entry_data->ready);
- vlc_sem_destroy (&entry_data->ready);
- free (entry_data);
+ ResumeThread (hThread);
return 0;
+}
-error:
- vlc_sem_destroy (&entry_data->ready);
- free (entry_data);
- return err;
+int vlc_clone (vlc_thread_t *p_handle, void *(*entry) (void *),
+ void *data, int priority)
+{
+ return vlc_clone_attr (p_handle, false, entry, data, priority);
}
-void vlc_join (vlc_thread_t handle, void **result)
+void vlc_join (vlc_thread_t th, void **result)
{
-#ifdef UNDER_CE
-# define handle handle->handle
-#endif
do
vlc_testcancel ();
- while (WaitForSingleObjectEx (handle, INFINITE, TRUE)
+ while (WaitForSingleObjectEx (th->id, INFINITE, TRUE)
== WAIT_IO_COMPLETION);
- CloseHandle (handle);
- assert (result == NULL); /* <- FIXME if ever needed */
+ if (result != NULL)
+ *result = th->data;
+ CloseHandle (th->id);
#ifdef UNDER_CE
-# undef handle
- CloseHandle (handle->cancel_event);
- free (handle);
+ CloseHandle (th->cancel_event);
#endif
+ free (th);
}
-void vlc_detach (vlc_thread_t handle)
+int vlc_clone_detach (vlc_thread_t *p_handle, void *(*entry) (void *),
+ void *data, int priority)
{
-#ifndef UNDER_CE
- CloseHandle (handle);
-#else
- /* FIXME: handle->cancel_event leak */
- CloseHandle (handle->handle);
- free (handle);
-#endif
+ vlc_thread_t th;
+ if (p_handle == NULL)
+ p_handle = &th;
+
+ return vlc_clone_attr (p_handle, true, entry, data, priority);
+}
+
+int vlc_set_priority (vlc_thread_t th, int priority)
+{
+ if (!SetThreadPriority (th->id, priority))
+ return VLC_EGENERIC;
+ return VLC_SUCCESS;
}
/*** Thread cancellation ***/
/* APC procedure for thread cancellation */
-static void CALLBACK vlc_cancel_self (ULONG_PTR dummy)
+static void CALLBACK vlc_cancel_self (ULONG_PTR self)
{
- vlc_cancel_t *nfo = vlc_threadvar_get (cancel_key);
+ struct vlc_thread *th = (void *)self;
- if (likely(nfo != NULL))
- nfo->killed = true;
-
- (void)dummy;
+ if (likely(th != NULL))
+ th->killed = true;
}
-void vlc_cancel (vlc_thread_t thread_id)
+void vlc_cancel (vlc_thread_t th)
{
#ifndef UNDER_CE
- QueueUserAPC (vlc_cancel_self, thread_id, 0);
+ QueueUserAPC (vlc_cancel_self, th->id, (uintptr_t)th);
#else
- SetEvent (thread_id->cancel_event);
+ SetEvent (th->cancel_event);
#endif
}
int vlc_savecancel (void)
{
- int state;
-
- vlc_cancel_t *nfo = vlc_threadvar_get (cancel_key);
- if (nfo == NULL)
+ struct vlc_thread *th = vlc_threadvar_get (thread_key);
+ if (th == NULL)
return false; /* Main thread - cannot be cancelled anyway */
- state = nfo->killable;
- nfo->killable = false;
+ int state = th->killable;
+ th->killable = false;
return state;
}
void vlc_restorecancel (int state)
{
- vlc_cancel_t *nfo = vlc_threadvar_get (cancel_key);
+ struct vlc_thread *th = vlc_threadvar_get (thread_key);
assert (state == false || state == true);
- if (nfo == NULL)
+ if (th == NULL)
return; /* Main thread - cannot be cancelled anyway */
- assert (!nfo->killable);
- nfo->killable = state != 0;
+ assert (!th->killable);
+ th->killable = state != 0;
}
void vlc_testcancel (void)
{
- vlc_cancel_t *nfo = vlc_threadvar_get (cancel_key);
- if (nfo == NULL)
+ struct vlc_thread *th = vlc_threadvar_get (thread_key);
+ if (th == NULL)
return; /* Main thread - cannot be cancelled anyway */
- if (nfo->killable && nfo->killed)
+ if (th->killable && th->killed)
{
- for (vlc_cleanup_t *p = nfo->cleaners; p != NULL; p = p->next)
+ for (vlc_cleanup_t *p = th->cleaners; p != NULL; p = p->next)
p->proc (p->data);
- vlc_threadvar_cleanup ();
+
+ th->data = NULL; /* TODO: special value? */
+ vlc_thread_cleanup (th);
#ifndef UNDER_CE
_endthreadex(0);
#else
* need to lock anything. */
va_list ap;
- vlc_cancel_t *nfo = vlc_threadvar_get (cancel_key);
- if (nfo == NULL)
+ struct vlc_thread *th = vlc_threadvar_get (thread_key);
+ if (th == NULL)
return; /* Main thread - cannot be cancelled anyway */
va_start (ap, cmd);
/* cleaner is a pointer to the caller stack, no need to allocate
* and copy anything. As a nice side effect, this cannot fail. */
vlc_cleanup_t *cleaner = va_arg (ap, vlc_cleanup_t *);
- cleaner->next = nfo->cleaners;
- nfo->cleaners = cleaner;
+ cleaner->next = th->cleaners;
+ th->cleaners = cleaner;
break;
}
case VLC_CLEANUP_POP:
{
- nfo->cleaners = nfo->cleaners->next;
+ th->cleaners = th->cleaners->next;
break;
}
}
(void)timer;
return 0;
}
+
+
+/*** CPU ***/
+unsigned vlc_GetCPUCount (void)
+{
+#ifndef UNDER_CE
+ DWORD process;
+ DWORD system;
+
+ if (GetProcessAffinityMask (GetCurrentProcess(), &process, &system))
+ return popcount (system);
+#endif
+ return 1;
+}
projects / vlc / blobdiff