/*****************************************************************************
* threads.c : threads implementation for the VideoLAN client
*****************************************************************************
- * Copyright (C) 1999-2007 the VideoLAN team
+ * Copyright (C) 1999-2008 the VideoLAN team
* $Id$
*
* Authors: Jean-Marc Dressler <polux@via.ecp.fr>
* Samuel Hocevar <sam@zoy.org>
* Gildas Bazin <gbazin@netcourrier.com>
* Clément Sténac
+ * Rémi Denis-Courmont
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
# include "config.h"
#endif
-#include <vlc/vlc.h>
+#include <vlc_common.h>
#include "libvlc.h"
+#include <stdarg.h>
#include <assert.h>
#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif
-
-#define VLC_THREADS_UNINITIALIZED 0
-#define VLC_THREADS_PENDING 1
-#define VLC_THREADS_ERROR 2
-#define VLC_THREADS_READY 3
+#include <signal.h>
/*****************************************************************************
* Global mutex for lazy initialization of the threads system
static volatile unsigned i_initializations = 0;
#if defined( LIBVLC_USE_PTHREAD )
+# include <sched.h>
+
static pthread_mutex_t once_mutex = PTHREAD_MUTEX_INITIALIZER;
+#else
+static vlc_threadvar_t cancel_key;
+#endif
+
+static struct
+{
+ vlc_dictionary_t list;
+ vlc_mutex_t lock;
+} named_mutexes;
+
+#ifdef HAVE_EXECINFO_H
+# include <execinfo.h>
#endif
/**
- * Global process-wide VLC object.
- * Contains inter-instance data, such as the module cache and global mutexes.
+ * Print a backtrace to the standard error for debugging purpose.
*/
-static libvlc_global_data_t *p_root;
-
-libvlc_global_data_t *vlc_global( void )
+void vlc_trace (const char *fn, const char *file, unsigned line)
{
- assert( i_initializations > 0 );
- return p_root;
+ fprintf (stderr, "at %s:%u in %s\n", file, line, fn);
+ fflush (stderr); /* needed before switch to low-level I/O */
+#ifdef HAVE_BACKTRACE
+ void *stack[20];
+ int len = backtrace (stack, sizeof (stack) / sizeof (stack[0]));
+ backtrace_symbols_fd (stack, len, 2);
+#endif
+#ifndef WIN32
+ fsync (2);
+#endif
}
-
-vlc_threadvar_t msg_context_global_key;
-
-#if defined(LIBVLC_USE_PTHREAD)
static inline unsigned long vlc_threadid (void)
{
+#if defined(LIBVLC_USE_PTHREAD)
union { pthread_t th; unsigned long int i; } v = { };
v.th = pthread_self ();
return v.i;
-}
+#elif defined (WIN32)
+ return GetCurrentThreadId ();
+
+#else
+ return 0;
+
+#endif
+}
/*****************************************************************************
* vlc_thread_fatal: Report an error from the threading layer
*****************************************************************************
* This is mostly meant for debugging.
*****************************************************************************/
-void vlc_pthread_fatal (const char *action, int error,
- const char *file, unsigned line)
+static void
+vlc_thread_fatal (const char *action, int error,
+ const char *function, const char *file, unsigned line)
{
- fprintf (stderr, "LibVLC fatal error %s in thread %lu at %s:%u: %d\n",
- action, vlc_threadid (), file, line, error);
- fflush (stderr);
+ fprintf (stderr, "LibVLC fatal error %s (%d) in thread %lu ",
+ action, error, vlc_threadid ());
+ vlc_trace (function, file, line);
/* Sometimes strerror_r() crashes too, so make sure we print an error
* message before we invoke it */
/* Avoid the strerror_r() prototype brain damage in glibc */
errno = error;
fprintf (stderr, " Error message: %m\n");
-#else
+#elif !defined (WIN32)
char buf[1000];
const char *msg;
}
fprintf (stderr, " Error message: %s\n", msg);
#endif
-
fflush (stderr);
+
abort ();
}
+
+#ifndef NDEBUG
+# define VLC_THREAD_ASSERT( action ) \
+ if (val) vlc_thread_fatal (action, val, __func__, __FILE__, __LINE__)
+#else
+# define VLC_THREAD_ASSERT( action ) ((void)val)
#endif
+/**
+ * Per-thread cancellation data
+ */
+#ifndef LIBVLC_USE_PTHREAD_CANCEL
+typedef struct vlc_cancel_t
+{
+ vlc_cleanup_t *cleaners;
+ bool killable;
+ bool killed;
+} vlc_cancel_t;
+
+# define VLC_CANCEL_INIT { NULL, true, false }
+#endif
/*****************************************************************************
* vlc_threads_init: initialize threads system
*****************************************************************************/
int vlc_threads_init( void )
{
- int i_ret = VLC_SUCCESS;
-
/* If we have lazy mutex initialization, use it. Otherwise, we just
* hope nothing wrong happens. */
#if defined( LIBVLC_USE_PTHREAD )
if( i_initializations == 0 )
{
- p_root = vlc_custom_create( NULL, sizeof( *p_root ),
- VLC_OBJECT_GENERIC, "root" );
- if( p_root == NULL )
- {
- i_ret = VLC_ENOMEM;
- goto out;
- }
-
- /* We should be safe now. Do all the initialization stuff we want. */
- vlc_threadvar_create( p_root, &msg_context_global_key );
+ vlc_dictionary_init (&named_mutexes.list, 0);
+ vlc_mutex_init (&named_mutexes.lock);
+#ifndef LIBVLC_USE_PTHREAD_CANCEL
+ vlc_threadvar_create( &cancel_key, free );
+#endif
}
i_initializations++;
-out:
- /* If we have lazy mutex initialization support, unlock the mutex.
- * Otherwize, we are screwed. */
#if defined( LIBVLC_USE_PTHREAD )
pthread_mutex_unlock( &once_mutex );
#endif
- return i_ret;
+ return VLC_SUCCESS;
}
/*****************************************************************************
assert( i_initializations > 0 );
if( i_initializations == 1 )
- vlc_object_release( p_root );
+ {
+#ifndef LIBVLC_USE_PTHREAD
+ vlc_threadvar_delete( &cancel_key );
+#endif
+ vlc_mutex_destroy (&named_mutexes.lock);
+ vlc_dictionary_clear (&named_mutexes.list);
+ }
i_initializations--;
#if defined( LIBVLC_USE_PTHREAD )
i_result = pthread_mutex_init( p_mutex, &attr );
pthread_mutexattr_destroy( &attr );
return i_result;
-#elif defined( UNDER_CE )
- InitializeCriticalSection( &p_mutex->csection );
- return 0;
#elif defined( WIN32 )
- *p_mutex = CreateMutex( 0, FALSE, 0 );
- return (*p_mutex != NULL) ? 0 : ENOMEM;
-
-#elif defined( HAVE_KERNEL_SCHEDULER_H )
- /* check the arguments and whether it's already been initialized */
- if( p_mutex == NULL )
- {
- return B_BAD_VALUE;
- }
-
- if( p_mutex->init == 9999 )
- {
- return EALREADY;
- }
-
- p_mutex->lock = create_sem( 1, "BeMutex" );
- if( p_mutex->lock < B_NO_ERROR )
- {
- return( -1 );
- }
-
- p_mutex->init = 9999;
- return B_OK;
+ InitializeCriticalSection (&p_mutex->mutex);
+ p_mutex->recursive = false;
+ return 0;
#endif
}
i_result = pthread_mutex_init( p_mutex, &attr );
pthread_mutexattr_destroy( &attr );
return( i_result );
+
#elif defined( WIN32 )
- /* Create mutex returns a recursive mutex */
- *p_mutex = CreateMutex( 0, FALSE, 0 );
- return (*p_mutex != NULL) ? 0 : ENOMEM;
-#else
-# error Unimplemented!
+ InitializeCriticalSection( &p_mutex->mutex );
+ p_mutex->owner = 0; /* the error value for GetThreadId()! */
+ p_mutex->recursion = 0;
+ p_mutex->recursive = true;
+ return 0;
+
#endif
}
-/*****************************************************************************
- * vlc_mutex_destroy: destroy a mutex, inner version
- *****************************************************************************/
-void __vlc_mutex_destroy( const char * psz_file, int i_line, vlc_mutex_t *p_mutex )
+/**
+ * Destroys a mutex. The mutex must not be locked.
+ *
+ * @param p_mutex mutex to destroy
+ * @return always succeeds
+ */
+void vlc_mutex_destroy (vlc_mutex_t *p_mutex)
{
#if defined( LIBVLC_USE_PTHREAD )
int val = pthread_mutex_destroy( p_mutex );
VLC_THREAD_ASSERT ("destroying mutex");
-#elif defined( UNDER_CE )
- VLC_UNUSED( psz_file); VLC_UNUSED( i_line );
+#elif defined( WIN32 )
+ DeleteCriticalSection (&p_mutex->mutex);
- DeleteCriticalSection( &p_mutex->csection );
+#endif
+}
+
+/**
+ * Acquires a mutex. If needed, waits for any other thread to release it.
+ * Beware of deadlocks when locking multiple mutexes at the same time,
+ * or when using mutexes from callbacks.
+ *
+ * @param p_mutex mutex initialized with vlc_mutex_init() or
+ * vlc_mutex_init_recursive()
+ */
+void vlc_mutex_lock (vlc_mutex_t *p_mutex)
+{
+#if defined(LIBVLC_USE_PTHREAD)
+ int val = pthread_mutex_lock( p_mutex );
+ VLC_THREAD_ASSERT ("locking mutex");
#elif defined( WIN32 )
- VLC_UNUSED( psz_file); VLC_UNUSED( i_line );
+ if (p_mutex->recursive)
+ {
+ DWORD self = GetCurrentThreadId ();
+
+ if ((DWORD)InterlockedCompareExchange (&p_mutex->owner, self,
+ self) == self)
+ { /* We already locked this recursive mutex */
+ p_mutex->recursion++;
+ return;
+ }
+
+ /* We need to lock this recursive mutex */
+ EnterCriticalSection (&p_mutex->mutex);
+ self = InterlockedExchange (&p_mutex->owner, self);
+ assert (self == 0); /* no previous owner */
+ return;
+ }
+ /* Non-recursive mutex */
+ EnterCriticalSection (&p_mutex->mutex);
+
+#endif
+}
- CloseHandle( *p_mutex );
-#elif defined( HAVE_KERNEL_SCHEDULER_H )
- if( p_mutex->init == 9999 )
- delete_sem( p_mutex->lock );
+/**
+ * Releases a mutex (or crashes if the mutex is not locked by the caller).
+ * @param p_mutex mutex locked with vlc_mutex_lock().
+ */
+void vlc_mutex_unlock (vlc_mutex_t *p_mutex)
+{
+#if defined(LIBVLC_USE_PTHREAD)
+ int val = pthread_mutex_unlock( p_mutex );
+ VLC_THREAD_ASSERT ("unlocking mutex");
+
+#elif defined( WIN32 )
+ if (p_mutex->recursive)
+ {
+ if (p_mutex->recursion != 0)
+ {
+ p_mutex->recursion--;
+ return; /* We still own this mutex */
+ }
- p_mutex->init = 0;
+ /* We release the mutex */
+ InterlockedExchange (&p_mutex->owner, 0);
+ /* fall through */
+ }
+ LeaveCriticalSection (&p_mutex->mutex);
#endif
}
/*****************************************************************************
- * vlc_cond_init: initialize a condition
+ * vlc_cond_init: initialize a condition variable
*****************************************************************************/
-int __vlc_cond_init( vlc_cond_t *p_condvar )
+int vlc_cond_init( vlc_cond_t *p_condvar )
{
#if defined( LIBVLC_USE_PTHREAD )
pthread_condattr_t attr;
pthread_condattr_destroy (&attr);
return ret;
-#elif defined( UNDER_CE ) || defined( WIN32 )
- /* Initialize counter */
- p_condvar->i_waiting_threads = 0;
-
- /* Create an auto-reset event. */
- p_condvar->event = CreateEvent( NULL, /* no security */
- FALSE, /* auto-reset event */
- FALSE, /* start non-signaled */
- NULL ); /* unnamed */
- return !p_condvar->event;
-
-#elif defined( HAVE_KERNEL_SCHEDULER_H )
- if( !p_condvar )
- {
- return B_BAD_VALUE;
- }
+#elif defined( WIN32 )
+ /* Create a manual-reset event (manual reset is needed for broadcast). */
+ *p_condvar = CreateEvent( NULL, TRUE, FALSE, NULL );
+ return *p_condvar ? 0 : ENOMEM;
+
+#endif
+}
+
+/**
+ * Destroys a condition variable. No threads shall be waiting or signaling the
+ * condition.
+ * @param p_condvar condition variable to destroy
+ */
+void vlc_cond_destroy (vlc_cond_t *p_condvar)
+{
+#if defined( LIBVLC_USE_PTHREAD )
+ int val = pthread_cond_destroy( p_condvar );
+ VLC_THREAD_ASSERT ("destroying condition");
+
+#elif defined( WIN32 )
+ CloseHandle( *p_condvar );
+
+#endif
+}
+
+/**
+ * Wakes up one thread waiting on a condition variable, if any.
+ * @param p_condvar condition variable
+ */
+void vlc_cond_signal (vlc_cond_t *p_condvar)
+{
+#if defined(LIBVLC_USE_PTHREAD)
+ int val = pthread_cond_signal( p_condvar );
+ VLC_THREAD_ASSERT ("signaling condition variable");
+
+#elif defined( WIN32 )
+ /* NOTE: This will cause a broadcast, that is wrong.
+ * This will also wake up the next waiting thread if no thread are yet
+ * waiting, which is also wrong. However both of these issues are allowed
+ * by the provision for spurious wakeups. Better have too many wakeups
+ * than too few (= deadlocks). */
+ SetEvent (*p_condvar);
- if( p_condvar->init == 9999 )
+#endif
+}
+
+/**
+ * Wakes up all threads (if any) waiting on a condition variable.
+ * @param p_cond condition variable
+ */
+void vlc_cond_broadcast (vlc_cond_t *p_condvar)
+{
+#if defined (LIBVLC_USE_PTHREAD)
+ pthread_cond_broadcast (p_condvar);
+
+#elif defined (WIN32)
+ SetEvent (*p_condvar);
+
+#endif
+}
+
+#ifdef UNDER_CE
+# warning FIXME
+# define WaitForMultipleObjectsEx(a,b,c) WaitForMultipleObjects(a,b)
+#endif
+
+/**
+ * Waits for a condition variable. The calling thread will be suspended until
+ * another thread calls vlc_cond_signal() or vlc_cond_broadcast() on the same
+ * condition variable, the thread is cancelled with vlc_cancel(), or the
+ * system causes a "spurious" unsolicited wake-up.
+ *
+ * A mutex is needed to wait on a condition variable. It must <b>not</b> be
+ * a recursive mutex. Although it is possible to use the same mutex for
+ * multiple condition, it is not valid to use different mutexes for the same
+ * condition variable at the same time from different threads.
+ *
+ * In case of thread cancellation, the mutex is always locked before
+ * cancellation proceeds.
+ *
+ * The canonical way to use a condition variable to wait for event foobar is:
+ @code
+ vlc_mutex_lock (&lock);
+ mutex_cleanup_push (&lock); // release the mutex in case of cancellation
+
+ while (!foobar)
+ vlc_cond_wait (&wait, &lock);
+
+ --- foobar is now true, do something about it here --
+
+ vlc_cleanup_run (); // release the mutex
+ @endcode
+ *
+ * @param p_condvar condition variable to wait on
+ * @param p_mutex mutex which is unlocked while waiting,
+ * then locked again when waking up.
+ * @param deadline <b>absolute</b> timeout
+ *
+ * @return 0 if the condition was signaled, an error code in case of timeout.
+ */
+void vlc_cond_wait (vlc_cond_t *p_condvar, vlc_mutex_t *p_mutex)
+{
+#if defined(LIBVLC_USE_PTHREAD)
+ int val = pthread_cond_wait( p_condvar, p_mutex );
+ VLC_THREAD_ASSERT ("waiting on condition");
+
+#elif defined( WIN32 )
+ DWORD result;
+
+ assert (!p_mutex->recursive);
+ do
{
- return EALREADY;
+ vlc_testcancel ();
+ LeaveCriticalSection (&p_mutex->mutex);
+ result = WaitForSingleObjectEx (*p_condvar, INFINITE, TRUE);
+ EnterCriticalSection (&p_mutex->mutex);
}
+ while (result == WAIT_IO_COMPLETION);
- p_condvar->thread = -1;
- p_condvar->init = 9999;
- return 0;
+ ResetEvent (*p_condvar);
#endif
}
-/*****************************************************************************
- * vlc_cond_destroy: destroy a condition, inner version
- *****************************************************************************/
-void __vlc_cond_destroy( const char * psz_file, int i_line, vlc_cond_t *p_condvar )
+/**
+ * Waits for a condition variable up to a certain date.
+ * This works like vlc_cond_wait(), except for the additional timeout.
+ *
+ * @param p_condvar condition variable to wait on
+ * @param p_mutex mutex which is unlocked while waiting,
+ * then locked again when waking up.
+ * @param deadline <b>absolute</b> timeout
+ *
+ * @return 0 if the condition was signaled, an error code in case of timeout.
+ */
+int vlc_cond_timedwait (vlc_cond_t *p_condvar, vlc_mutex_t *p_mutex,
+ mtime_t deadline)
{
-#if defined( LIBVLC_USE_PTHREAD )
- int val = pthread_cond_destroy( p_condvar );
- VLC_THREAD_ASSERT ("destroying condition");
+#if defined(LIBVLC_USE_PTHREAD)
+ lldiv_t d = lldiv( deadline, CLOCK_FREQ );
+ struct timespec ts = { d.quot, d.rem * (1000000000 / CLOCK_FREQ) };
-#elif defined( UNDER_CE ) || defined( WIN32 )
- VLC_UNUSED( psz_file); VLC_UNUSED( i_line );
+ int val = pthread_cond_timedwait (p_condvar, p_mutex, &ts);
+ if (val != ETIMEDOUT)
+ VLC_THREAD_ASSERT ("timed-waiting on condition");
+ return val;
+
+#elif defined( WIN32 )
+ DWORD result;
- CloseHandle( p_condvar->event );
+ assert (!p_mutex->recursive);
+ do
+ {
+ vlc_testcancel ();
+
+ mtime_t total = (deadline - mdate ())/1000;
+ if( total < 0 )
+ total = 0;
-#elif defined( HAVE_KERNEL_SCHEDULER_H )
- p_condvar->init = 0;
+ DWORD delay = (total > 0x7fffffff) ? 0x7fffffff : total;
+ LeaveCriticalSection (&p_mutex->mutex);
+ result = WaitForSingleObjectEx (*p_condvar, delay, TRUE);
+ EnterCriticalSection (&p_mutex->mutex);
+ }
+ while (result == WAIT_IO_COMPLETION);
+
+ ResetEvent (*p_condvar);
+
+ return (result == WAIT_OBJECT_0) ? 0 : ETIMEDOUT;
#endif
}
/*****************************************************************************
* vlc_tls_create: create a thread-local variable
*****************************************************************************/
-int __vlc_threadvar_create( vlc_threadvar_t *p_tls )
+int vlc_threadvar_create( vlc_threadvar_t *p_tls, void (*destr) (void *) )
{
- int i_ret = -1;
+ int i_ret;
#if defined( LIBVLC_USE_PTHREAD )
- i_ret = pthread_key_create( p_tls, NULL );
+ i_ret = pthread_key_create( p_tls, destr );
#elif defined( UNDER_CE )
+ i_ret = ENOSYS;
#elif defined( WIN32 )
+ /* FIXME: remember/use the destr() callback and stop leaking whatever */
*p_tls = TlsAlloc();
i_ret = (*p_tls == TLS_OUT_OF_INDEXES) ? EAGAIN : 0;
#else
return i_ret;
}
-/*****************************************************************************
- * vlc_thread_create: create a thread, inner version
- *****************************************************************************
- * Note that i_priority is only taken into account on platforms supporting
- * userland real-time priority threads.
- *****************************************************************************/
-int __vlc_thread_create( vlc_object_t *p_this, const char * psz_file, int i_line,
- const char *psz_name, void * ( *func ) ( void * ),
- int i_priority, bool b_wait )
+void vlc_threadvar_delete (vlc_threadvar_t *p_tls)
{
- int i_ret;
- void *p_data = (void *)p_this;
- vlc_object_internals_t *p_priv = vlc_internals( p_this );
-
- vlc_mutex_lock( &p_this->object_lock );
-
#if defined( LIBVLC_USE_PTHREAD )
- i_ret = pthread_create( &p_priv->thread_id, NULL, func, p_data );
+ pthread_key_delete (*p_tls);
+#elif defined( UNDER_CE )
+#elif defined( WIN32 )
+ TlsFree (*p_tls);
+#else
+# error Unimplemented!
+#endif
+}
-#ifndef __APPLE__
- if( config_GetInt( p_this, "rt-priority" ) > 0 )
+#if defined (LIBVLC_USE_PTHREAD)
+#elif defined (WIN32)
+static unsigned __stdcall vlc_entry (void *data)
+{
+ vlc_cancel_t cancel_data = VLC_CANCEL_INIT;
+ vlc_thread_t self = data;
+
+ vlc_threadvar_set (&cancel_key, &cancel_data);
+ self->data = self->entry (self->data);
+ return 0;
+}
#endif
+
+/**
+ * Creates and starts new thread.
+ *
+ * @param p_handle [OUT] pointer to write the handle of the created thread to
+ * @param entry entry point for the thread
+ * @param data data parameter given to the entry point
+ * @param priority thread priority value
+ * @return 0 on success, a standard error code on error.
+ */
+int vlc_clone (vlc_thread_t *p_handle, void * (*entry) (void *), void *data,
+ int priority)
+{
+ int ret;
+
+#if defined( LIBVLC_USE_PTHREAD )
+ pthread_attr_t attr;
+ pthread_attr_init (&attr);
+
+ /* Block the signals that signals interface plugin handles.
+ * If the LibVLC caller wants to handle some signals by itself, it should
+ * block these before whenever invoking LibVLC. And it must obviously not
+ * start the VLC signals interface plugin.
+ *
+ * LibVLC will normally ignore any interruption caused by an asynchronous
+ * signal during a system call. But there may well be some buggy cases
+ * where it fails to handle EINTR (bug reports welcome). Some underlying
+ * libraries might also not handle EINTR properly.
+ */
+ sigset_t oldset;
{
- int i_error, i_policy;
- struct sched_param param;
+ sigset_t set;
+ sigemptyset (&set);
+ sigdelset (&set, SIGHUP);
+ sigaddset (&set, SIGINT);
+ sigaddset (&set, SIGQUIT);
+ sigaddset (&set, SIGTERM);
+
+ sigaddset (&set, SIGPIPE); /* We don't want this one, really! */
+ pthread_sigmask (SIG_BLOCK, &set, &oldset);
+ }
+ {
+ struct sched_param sp = { .sched_priority = priority, };
+ int policy;
- memset( ¶m, 0, sizeof(struct sched_param) );
- if( config_GetType( p_this, "rt-offset" ) )
- i_priority += config_GetInt( p_this, "rt-offset" );
- if( i_priority <= 0 )
- {
- param.sched_priority = (-1) * i_priority;
- i_policy = SCHED_OTHER;
- }
+ if (sp.sched_priority <= 0)
+ sp.sched_priority += sched_get_priority_max (policy = SCHED_OTHER);
else
- {
- param.sched_priority = i_priority;
- i_policy = SCHED_RR;
- }
- if( (i_error = pthread_setschedparam( p_priv->thread_id,
- i_policy, ¶m )) )
- {
- errno = i_error;
- msg_Warn( p_this, "couldn't set thread priority (%s:%d): %m",
- psz_file, i_line );
- i_priority = 0;
- }
+ sp.sched_priority += sched_get_priority_min (policy = SCHED_RR);
+
+ pthread_attr_setschedpolicy (&attr, policy);
+ pthread_attr_setschedparam (&attr, &sp);
}
-#ifndef __APPLE__
- else
- i_priority = 0;
+
+ /* The thread stack size.
+ * The lower the value, the less address space per thread, the highest
+ * maximum simultaneous threads per process. Too low values will cause
+ * stack overflows and weird crashes. Set with caution. Also keep in mind
+ * that 64-bits platforms consume more stack than 32-bits one.
+ *
+ * Thanks to on-demand paging, thread stack size only affects address space
+ * consumption. In terms of memory, threads only use what they need
+ * (rounded up to the page boundary).
+ *
+ * For example, on Linux i386, the default is 2 mega-bytes, which supports
+ * about 320 threads per processes. */
+#define VLC_STACKSIZE (128 * sizeof (void *) * 1024)
+
+#ifdef VLC_STACKSIZE
+ ret = pthread_attr_setstacksize (&attr, VLC_STACKSIZE);
+ assert (ret == 0); /* fails iif VLC_STACKSIZE is invalid */
#endif
+ ret = pthread_create (p_handle, &attr, entry, data);
+ pthread_sigmask (SIG_SETMASK, &oldset, NULL);
+ pthread_attr_destroy (&attr);
+
#elif defined( WIN32 ) || defined( 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) */
+ /* 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) */
+ HANDLE hThread;
+ vlc_thread_t th = malloc (sizeof (*th));
+
+ if (th == NULL)
+ return ENOMEM;
+
+ th->data = data;
+ th->entry = entry;
#if defined( UNDER_CE )
- HANDLE hThread = CreateThread( NULL, 0, (LPTHREAD_START_ROUTINE)func,
- (LPVOID)p_data, CREATE_SUSPENDED,
- NULL );
+ hThread = CreateThread (NULL, 0, vlc_entry, th, CREATE_SUSPENDED, NULL);
#else
- HANDLE hThread = (HANDLE)(uintptr_t)
- _beginthreadex( NULL, 0, (LPTHREAD_START_ROUTINE)func,
- (void *)p_data, CREATE_SUSPENDED, NULL );
+ hThread = (HANDLE)(uintptr_t)
+ _beginthreadex (NULL, 0, vlc_entry, th, CREATE_SUSPENDED, NULL);
#endif
- p_priv->thread_id = hThread;
- ResumeThread(hThread);
- }
- i_ret = ( p_priv->thread_id ? 0 : errno );
-
- if( !i_ret && i_priority )
+ if (hThread)
{
- if( !SetThreadPriority(p_priv->thread_id, i_priority) )
+ /* Thread closes the handle when exiting, duplicate it here
+ * to be on the safe side when joining. */
+ if (!DuplicateHandle (GetCurrentProcess (), hThread,
+ GetCurrentProcess (), &th->handle, 0, FALSE,
+ DUPLICATE_SAME_ACCESS))
{
- msg_Warn( p_this, "couldn't set a faster priority" );
- i_priority = 0;
+ CloseHandle (hThread);
+ free (th);
+ return ENOMEM;
}
+
+ ResumeThread (hThread);
+ if (priority)
+ SetThreadPriority (hThread, priority);
+
+ ret = 0;
+ *p_handle = th;
}
+ else
+ {
+ ret = errno;
+ free (th);
+ }
+
+#endif
+ return ret;
+}
+
+#if defined (WIN32)
+/* APC procedure for thread cancellation */
+static void CALLBACK vlc_cancel_self (ULONG_PTR dummy)
+{
+ (void)dummy;
+ vlc_control_cancel (VLC_DO_CANCEL);
+}
+#endif
+
+/**
+ * Marks a thread as cancelled. Next time the target thread reaches a
+ * cancellation point (while not having disabled cancellation), it will
+ * run its cancellation cleanup handler, the thread variable destructors, and
+ * terminate. vlc_join() must be used afterward regardless of a thread being
+ * cancelled or not.
+ */
+void vlc_cancel (vlc_thread_t thread_id)
+{
+#if defined (LIBVLC_USE_PTHREAD_CANCEL)
+ pthread_cancel (thread_id);
+#elif defined (WIN32)
+ QueueUserAPC (vlc_cancel_self, thread_id->handle, 0);
+#else
+# warning vlc_cancel is not implemented!
+#endif
+}
+
+/**
+ * Waits for a thread to complete (if needed), and destroys it.
+ * This is a cancellation point; in case of cancellation, the join does _not_
+ * occur.
+ *
+ * @param handle thread handle
+ * @param p_result [OUT] pointer to write the thread return value or NULL
+ * @return 0 on success, a standard error code otherwise.
+ */
+void vlc_join (vlc_thread_t handle, void **result)
+{
+#if defined( LIBVLC_USE_PTHREAD )
+ int val = pthread_join (handle, result);
+ if (val)
+ vlc_thread_fatal ("joining thread", val, __func__, __FILE__, __LINE__);
+
+#elif defined( UNDER_CE ) || defined( WIN32 )
+ do
+ vlc_testcancel ();
+ while (WaitForSingleObjectEx (handle->handle, INFINITE, TRUE)
+ == WAIT_IO_COMPLETION);
+
+ CloseHandle (handle->handle);
+ if (result)
+ *result = handle->data;
+ free (handle);
+
+#endif
+}
+
+
+struct vlc_thread_boot
+{
+ void * (*entry) (vlc_object_t *);
+ vlc_object_t *object;
+};
+
+static void *thread_entry (void *data)
+{
+ vlc_object_t *obj = ((struct vlc_thread_boot *)data)->object;
+ void *(*func) (vlc_object_t *) = ((struct vlc_thread_boot *)data)->entry;
-#elif defined( HAVE_KERNEL_SCHEDULER_H )
- p_priv->thread_id = spawn_thread( (thread_func)func, psz_name,
- i_priority, p_data );
- i_ret = resume_thread( p_priv->thread_id );
+ free (data);
+ msg_Dbg (obj, "thread started");
+ func (obj);
+ msg_Dbg (obj, "thread ended");
+ return NULL;
+}
+
+/*****************************************************************************
+ * vlc_thread_create: create a thread, inner version
+ *****************************************************************************
+ * Note that i_priority is only taken into account on platforms supporting
+ * userland real-time priority threads.
+ *****************************************************************************/
+int __vlc_thread_create( vlc_object_t *p_this, const char * psz_file, int i_line,
+ const char *psz_name, void * ( *func ) ( vlc_object_t * ),
+ int i_priority, bool b_wait )
+{
+ int i_ret;
+ vlc_object_internals_t *p_priv = vlc_internals( p_this );
+
+ struct vlc_thread_boot *boot = malloc (sizeof (*boot));
+ if (boot == NULL)
+ return errno;
+ boot->entry = func;
+ boot->object = p_this;
+
+ vlc_object_lock( p_this );
+
+ /* Make sure we don't re-create a thread if the object has already one */
+ assert( !p_priv->b_thread );
+
+#if defined( LIBVLC_USE_PTHREAD )
+#ifndef __APPLE__
+ if( config_GetInt( p_this, "rt-priority" ) > 0 )
+#endif
+ {
+ /* Hack to avoid error msg */
+ if( config_GetType( p_this, "rt-offset" ) )
+ i_priority += config_GetInt( p_this, "rt-offset" );
+ }
#endif
+ i_ret = vlc_clone( &p_priv->thread_id, thread_entry, boot, i_priority );
if( i_ret == 0 )
{
if( b_wait )
{
- msg_Dbg( p_this, "waiting for thread completion" );
+ msg_Dbg( p_this, "waiting for thread initialization" );
vlc_object_wait( p_this );
}
psz_name, psz_file, i_line );
}
- vlc_mutex_unlock( &p_this->object_lock );
+ vlc_object_unlock( p_this );
return i_ret;
}
{
vlc_object_internals_t *p_priv = vlc_internals( p_this );
+ if( !p_priv->b_thread )
+ {
+ msg_Err( p_this, "couldn't set priority of non-existent thread" );
+ return ESRCH;
+ }
+
#if defined( LIBVLC_USE_PTHREAD )
# ifndef __APPLE__
if( config_GetInt( p_this, "rt-priority" ) > 0 )
param.sched_priority = i_priority;
i_policy = SCHED_RR;
}
- if( !p_priv->thread_id )
- p_priv->thread_id = pthread_self();
if( (i_error = pthread_setschedparam( p_priv->thread_id,
- i_policy, ¶m )) )
+ i_policy, ¶m )) )
{
errno = i_error;
msg_Warn( p_this, "couldn't set thread priority (%s:%d): %m",
#elif defined( WIN32 ) || defined( UNDER_CE )
VLC_UNUSED( psz_file); VLC_UNUSED( i_line );
- if( !p_priv->thread_id )
- p_priv->thread_id = GetCurrentThread();
- if( !SetThreadPriority(p_priv->thread_id, i_priority) )
+ if( !SetThreadPriority(p_priv->thread_id->handle, i_priority) )
{
msg_Warn( p_this, "couldn't set a faster priority" );
return 1;
return 0;
}
-/*****************************************************************************
- * vlc_thread_ready: tell the parent thread we were successfully spawned
- *****************************************************************************/
-void __vlc_thread_ready( vlc_object_t *p_this )
-{
- vlc_object_signal( p_this );
-}
-
/*****************************************************************************
* vlc_thread_join: wait until a thread exits, inner version
*****************************************************************************/
-void __vlc_thread_join( vlc_object_t *p_this, const char * psz_file, int i_line )
+void __vlc_thread_join( vlc_object_t *p_this )
{
vlc_object_internals_t *p_priv = vlc_internals( p_this );
- int i_ret = 0;
#if defined( LIBVLC_USE_PTHREAD )
- /* Make sure we do return if we are calling vlc_thread_join()
- * from the joined thread */
- if (pthread_equal (pthread_self (), p_priv->thread_id))
- i_ret = pthread_detach (p_priv->thread_id);
- else
- i_ret = pthread_join (p_priv->thread_id, NULL);
+ vlc_join (p_priv->thread_id, NULL);
#elif defined( UNDER_CE ) || defined( WIN32 )
- HMODULE hmodule;
- BOOL (WINAPI *OurGetThreadTimes)( HANDLE, FILETIME*, FILETIME*,
- FILETIME*, FILETIME* );
+ HANDLE hThread;
FILETIME create_ft, exit_ft, kernel_ft, user_ft;
int64_t real_time, kernel_time, user_time;
- HANDLE hThread;
- /*
- ** object will close its thread handle when destroyed, duplicate it here
- ** to be on the safe side
- */
if( ! DuplicateHandle(GetCurrentProcess(),
- p_priv->thread_id,
+ p_priv->thread_id->handle,
GetCurrentProcess(),
&hThread,
0,
DUPLICATE_SAME_ACCESS) )
{
p_priv->b_thread = false;
- i_ret = GetLastError();
- goto error;
+ return; /* We have a problem! */
}
- WaitForSingleObject( hThread, INFINITE );
-
-#if defined( UNDER_CE )
- hmodule = GetModuleHandle( _T("COREDLL") );
-#else
- hmodule = GetModuleHandle( _T("KERNEL32") );
-#endif
- OurGetThreadTimes = (BOOL (WINAPI*)( HANDLE, FILETIME*, FILETIME*,
- FILETIME*, FILETIME* ))
- GetProcAddress( hmodule, _T("GetThreadTimes") );
+ vlc_join( p_priv->thread_id, NULL );
- if( OurGetThreadTimes &&
- OurGetThreadTimes( hThread,
- &create_ft, &exit_ft, &kernel_ft, &user_ft ) )
+ if( GetThreadTimes( hThread, &create_ft, &exit_ft, &kernel_ft, &user_ft ) )
{
real_time =
((((int64_t)exit_ft.dwHighDateTime)<<32)| exit_ft.dwLowDateTime) -
(double)((user_time%(60*1000000))/1000000.0) );
}
CloseHandle( hThread );
-error:
-#elif defined( HAVE_KERNEL_SCHEDULER_H )
- int32_t exit_value;
- i_ret = (B_OK == wait_for_thread( p_priv->thread_id, &exit_value ));
+#else
+ vlc_join( p_priv->thread_id, NULL );
#endif
- if( i_ret )
+ p_priv->b_thread = false;
+}
+
+void vlc_thread_cancel (vlc_object_t *obj)
+{
+ vlc_object_internals_t *priv = vlc_internals (obj);
+
+ if (priv->b_thread)
+ vlc_cancel (priv->thread_id);
+}
+
+void vlc_control_cancel (int cmd, ...)
+{
+ /* NOTE: This function only modifies thread-specific data, so there is no
+ * need to lock anything. */
+#ifdef LIBVLC_USE_PTHREAD_CANCEL
+ (void) cmd;
+ assert (0);
+#else
+ va_list ap;
+
+ vlc_cancel_t *nfo = vlc_threadvar_get (&cancel_key);
+ if (nfo == NULL)
{
- errno = i_ret;
- msg_Err( p_this, "thread_join(%lu) failed at %s:%d (%m)",
- (unsigned long)p_priv->thread_id, psz_file, i_line );
+#ifdef WIN32
+ /* Main thread - cannot be cancelled anyway */
+ return;
+#else
+ nfo = malloc (sizeof (*nfo));
+ if (nfo == NULL)
+ return; /* Uho! Expect problems! */
+ *nfo = VLC_CANCEL_INIT;
+ vlc_threadvar_set (&cancel_key, nfo);
+#endif
}
- else
- msg_Dbg( p_this, "thread %lu joined (%s:%d)",
- (unsigned long)p_priv->thread_id, psz_file, i_line );
- p_priv->b_thread = false;
+ va_start (ap, cmd);
+ switch (cmd)
+ {
+ case VLC_SAVE_CANCEL:
+ {
+ int *p_state = va_arg (ap, int *);
+ *p_state = nfo->killable;
+ nfo->killable = false;
+ break;
+ }
+
+ case VLC_RESTORE_CANCEL:
+ {
+ int state = va_arg (ap, int);
+ nfo->killable = state != 0;
+ break;
+ }
+
+ case VLC_TEST_CANCEL:
+ if (nfo->killable && nfo->killed)
+ {
+ for (vlc_cleanup_t *p = nfo->cleaners; p != NULL; p = p->next)
+ p->proc (p->data);
+#ifndef WIN32
+ free (nfo);
+#endif
+#if defined (LIBVLC_USE_PTHREAD)
+ pthread_exit (PTHREAD_CANCELLED);
+#elif defined (UNDER_CE)
+ ExitThread(0);
+#elif defined (WIN32)
+ _endthread ();
+#else
+# error Not implemented!
+#endif
+ }
+ break;
+
+ case VLC_DO_CANCEL:
+ nfo->killed = true;
+ break;
+
+ case VLC_CLEANUP_PUSH:
+ {
+ /* 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;
+ break;
+ }
+
+ case VLC_CLEANUP_POP:
+ {
+ nfo->cleaners = nfo->cleaners->next;
+ break;
+ }
+ }
+ va_end (ap);
+#endif
+}
+
+
+#undef var_AcquireMutex
+/**
+ * Finds a process-wide mutex, creates it if needed, and locks it.
+ * Unlock with vlc_mutex_unlock().
+ * FIXME: This is very inefficient, this is not memory-safe and this leaks
+ * memory. Use static locks instead.
+ */
+vlc_mutex_t *var_AcquireMutex( const char *name )
+{
+ vlc_mutex_t *lock;
+
+ vlc_mutex_lock (&named_mutexes.lock);
+ lock = vlc_dictionary_value_for_key (&named_mutexes.list, name);
+ if (lock == kVLCDictionaryNotFound)
+ {
+ lock = malloc (sizeof (*lock));
+ vlc_mutex_init (lock);
+ vlc_dictionary_insert (&named_mutexes.list, name, lock);
+ }
+ vlc_mutex_unlock (&named_mutexes.lock);
+
+ vlc_mutex_lock (lock);
+ return lock;
}
projects / vlc / blobdiff