/*****************************************************************************
* 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>
# 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
+#include <signal.h>
#define VLC_THREADS_UNINITIALIZED 0
#define VLC_THREADS_PENDING 1
static volatile unsigned i_initializations = 0;
#if defined( LIBVLC_USE_PTHREAD )
+# include <sched.h>
+
static pthread_mutex_t once_mutex = PTHREAD_MUTEX_INITIALIZER;
#endif
return p_root;
}
+#ifndef NDEBUG
+/**
+ * Object running the current thread
+ */
+static vlc_threadvar_t thread_object_key;
+
+vlc_object_t *vlc_threadobj (void)
+{
+ return vlc_threadvar_get (&thread_object_key);
+}
+#endif
vlc_threadvar_t msg_context_global_key;
return v.i;
}
+#if defined(HAVE_EXECINFO_H) && defined(HAVE_BACKTRACE)
+# include <execinfo.h>
+#endif
/*****************************************************************************
* vlc_thread_fatal: Report an error from the threading layer
{
fprintf (stderr, "LibVLC fatal error %s in thread %lu at %s:%u: %d\n",
action, vlc_threadid (), file, line, error);
- fflush (stderr);
/* Sometimes strerror_r() crashes too, so make sure we print an error
* message before we invoke it */
#ifdef __GLIBC__
/* Avoid the strerror_r() prototype brain damage in glibc */
errno = error;
- fprintf (stderr, " Error message: %m\n");
+ fprintf (stderr, " Error message: %m at:\n");
#else
char buf[1000];
const char *msg;
}
fprintf (stderr, " Error message: %s\n", msg);
#endif
-
fflush (stderr);
+
+#ifdef HAVE_BACKTRACE
+ void *stack[20];
+ int len = backtrace (stack, sizeof (stack) / sizeof (stack[0]));
+ backtrace_symbols_fd (stack, len, 2);
+#endif
+
abort ();
}
-#endif
+#else
+void vlc_pthread_fatal (const char *action, int error,
+ const char *file, unsigned line)
+{
+ (void)action; (void)error; (void)file; (void)line;
+ abort();
+}
+static vlc_threadvar_t cancel_key;
+#endif
/*****************************************************************************
* vlc_threads_init: initialize threads system
if( i_initializations == 0 )
{
- p_root = vlc_custom_create( NULL, sizeof( *p_root ),
+ p_root = vlc_custom_create( (vlc_object_t *)NULL, sizeof( *p_root ),
VLC_OBJECT_GENERIC, "root" );
if( p_root == NULL )
{
}
/* We should be safe now. Do all the initialization stuff we want. */
- vlc_threadvar_create( p_root, &msg_context_global_key );
+#ifndef NDEBUG
+ vlc_threadvar_create( &thread_object_key, NULL );
+#endif
+ vlc_threadvar_create( &msg_context_global_key, msg_StackDestroy );
+#ifndef LIBVLC_USE_PTHREAD
+ vlc_threadvar_create( &cancel_key, free );
+#endif
}
i_initializations++;
assert( i_initializations > 0 );
if( i_initializations == 1 )
+ {
vlc_object_release( p_root );
+#ifndef LIBVLC_USE_PTHREAD
+ vlc_threadvar_delete( &cancel_key );
+#endif
+ vlc_threadvar_delete( &msg_context_global_key );
+#ifndef NDEBUG
+ vlc_threadvar_delete( &thread_object_key );
+#endif
+ }
i_initializations--;
#if defined( LIBVLC_USE_PTHREAD )
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;
+ *p_condvar = CreateEvent( NULL, /* no security */
+ FALSE, /* auto-reset event */
+ FALSE, /* start non-signaled */
+ NULL ); /* unnamed */
+ return *p_condvar ? 0 : ENOMEM;
#elif defined( HAVE_KERNEL_SCHEDULER_H )
if( !p_condvar )
#elif defined( UNDER_CE ) || defined( WIN32 )
VLC_UNUSED( psz_file); VLC_UNUSED( i_line );
- CloseHandle( p_condvar->event );
+ CloseHandle( *p_condvar );
#elif defined( HAVE_KERNEL_SCHEDULER_H )
p_condvar->init = 0;
/*****************************************************************************
* 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_thread_t self = 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;
-#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 (*p_handle));
+
+ 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);
+ }
+
+#elif defined( HAVE_KERNEL_SCHEDULER_H )
+ *p_handle = spawn_thread( entry, psz_name, priority, data );
+ ret = resume_thread( *p_handle );
+
+#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)
+ pthread_cancel (thread_id);
+#elif defined (WIN32)
+ QueueUserAPC (vlc_cancel_self, thread_id->handle, 0);
+#endif
+}
+
+/**
+ * Waits for a thread to complete (if needed), and destroys it.
+ * @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.
+ */
+int vlc_join (vlc_thread_t handle, void **result)
+{
+#if defined( LIBVLC_USE_PTHREAD )
+ return pthread_join (handle, result);
+
+#elif defined( UNDER_CE ) || defined( WIN32 )
+ WaitForSingleObject (handle->handle, INFINITE);
+ CloseHandle (handle->handle);
+ if (result)
+ *result = handle->data;
+ free (handle);
+ return 0;
#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 );
+ int32_t exit_value;
+ ret = (B_OK == wait_for_thread( p_priv->thread_id, &exit_value ));
+ if( !ret && result )
+ *result = (void *)exit_value;
+
+ return ret;
+#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;
+ free (data);
+#ifndef NDEBUG
+ vlc_threadvar_set (&thread_object_key, obj);
+#endif
+ 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
*****************************************************************************/
/* 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))
+ {
+ msg_Warn (p_this, "joining the active thread (VLC might crash)");
i_ret = pthread_detach (p_priv->thread_id);
+ }
else
- i_ret = pthread_join (p_priv->thread_id, NULL);
+ i_ret = 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,
goto error;
}
- WaitForSingleObject( hThread, INFINITE );
+ vlc_join( p_priv->thread_id, NULL );
-#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") );
-
- 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) -
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
+ i_ret = vlc_join( p_priv->thread_id, NULL );
#endif
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);
+}
+
+typedef struct vlc_cleanup_t
+{
+ struct vlc_cleanup_t *next;
+ void (*proc) (void *);
+ void *data;
+} vlc_cleanup_t;
+
+typedef struct vlc_cancel_t
+{
+ vlc_cleanup_t *cleaners;
+ bool killable;
+ bool killed;
+} vlc_cancel_t;
+
+void vlc_control_cancel (int cmd, ...)
+{
+#ifdef LIBVLC_USE_PTHREAD
+ (void) cmd;
+ assert (0);
+#else
+ va_list ap;
+
+ va_start (ap, cmd);
+
+ vlc_cancel_t *nfo = vlc_threadvar_get (&cancel_key);
+ if (nfo == NULL)
+ {
+ nfo = malloc (sizeof (*nfo));
+ if (nfo == NULL)
+ abort ();
+ nfo->cleaners = NULL;
+ nfo->killed = false;
+ nfo->killable = true;
+ }
+
+ 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);
+ free (nfo);
+#if defined (LIBVLC_USE_PTHREAD)
+ pthread_exit (PTHREAD_CANCELLED);
+#elif defined (WIN32)
+ _endthread ();
+#else
+# error Not implemented!
+#endif
+ }
+ break;
+
+ case VLC_DO_CANCEL:
+ nfo->killed = true;
+ break;
+ }
+ va_end (ap);
+#endif
+}
projects / vlc / blobdiff