Use size_t or ssize_t when appropriate
[vlc.git] / src / misc / objects.c
1 /*****************************************************************************
2  * objects.c: vlc_object_t handling
3  *****************************************************************************
4  * Copyright (C) 2004 the VideoLAN team
5  * $Id$
6  *
7  * Authors: Samuel Hocevar <sam@zoy.org>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
22  *****************************************************************************/
23
24 /**
25  * \file
26  * This file contains the functions to handle the vlc_object_t type
27  */
28
29
30 /*****************************************************************************
31  * Preamble
32  *****************************************************************************/
33 #include <vlc/vlc.h>
34
35 #ifdef HAVE_STDLIB_H
36 #   include <stdlib.h>                                          /* realloc() */
37 #endif
38
39 #include "../libvlc.h"
40 #include <vlc_vout.h>
41 #include <vlc_aout.h>
42 #include "audio_output/aout_internal.h"
43
44 #include <vlc_access.h>
45 #include <vlc_demux.h>
46 #include <vlc_stream.h>
47
48 #include <vlc_sout.h>
49 #include "stream_output/stream_output.h"
50
51 #include "vlc_playlist.h"
52 #include "vlc_interface.h"
53 #include "vlc_codec.h"
54 #include "vlc_filter.h"
55
56 #include "vlc_httpd.h"
57 #include "vlc_vlm.h"
58 #include "vlc_vod.h"
59 #include "vlc_tls.h"
60 #include "vlc_xml.h"
61 #include "vlc_osd.h"
62 #include "vlc_meta.h"
63
64 #include "variables.h"
65
66 /*****************************************************************************
67  * Local prototypes
68  *****************************************************************************/
69 static int  DumpCommand( vlc_object_t *, char const *,
70                          vlc_value_t, vlc_value_t, void * );
71
72 static vlc_object_t * FindObject    ( vlc_object_t *, int, int );
73 static void           DetachObject  ( vlc_object_t * );
74 static void           PrintObject   ( vlc_object_t *, const char * );
75 static void           DumpStructure ( vlc_object_t *, int, char * );
76 static int            FindIndex     ( vlc_object_t *, vlc_object_t **, int );
77 static void           SetAttachment ( vlc_object_t *, vlc_bool_t );
78
79 static vlc_list_t   * NewList       ( int );
80 static void           ListReplace   ( vlc_list_t *, vlc_object_t *, int );
81 /*static void           ListAppend    ( vlc_list_t *, vlc_object_t * );*/
82 static int            CountChildren ( vlc_object_t *, int );
83 static void           ListChildren  ( vlc_list_t *, vlc_object_t *, int );
84
85 /*****************************************************************************
86  * Local structure lock
87  *****************************************************************************/
88 static vlc_mutex_t    structure_lock;
89
90 vlc_object_t *vlc_custom_create( vlc_object_t *p_this, size_t i_size,
91                                  int i_type, const char *psz_type )
92 {
93     vlc_object_t * p_new = NULL;
94
95     if( i_type == VLC_OBJECT_GLOBAL )
96     {
97         p_new = p_this;
98     }
99     else
100     {
101         p_new = malloc( i_size );
102         if( !p_new ) return NULL;
103         memset( p_new, 0, i_size );
104     }
105
106     p_new->i_object_type = i_type;
107     p_new->psz_object_type = psz_type;
108
109     p_new->psz_object_name = NULL;
110
111     p_new->b_die = VLC_FALSE;
112     p_new->b_error = VLC_FALSE;
113     p_new->b_dead = VLC_FALSE;
114     p_new->b_attached = VLC_FALSE;
115     p_new->b_force = VLC_FALSE;
116
117     p_new->psz_header = NULL;
118
119     p_new->i_flags = 0;
120     if( p_this->i_flags & OBJECT_FLAGS_NODBG )
121         p_new->i_flags |= OBJECT_FLAGS_NODBG;
122     if( p_this->i_flags & OBJECT_FLAGS_QUIET )
123         p_new->i_flags |= OBJECT_FLAGS_QUIET;
124     if( p_this->i_flags & OBJECT_FLAGS_NOINTERACT )
125         p_new->i_flags |= OBJECT_FLAGS_NOINTERACT;
126
127     p_new->i_vars = 0;
128     p_new->p_vars = (variable_t *)malloc( 16 * sizeof( variable_t ) );
129
130     if( !p_new->p_vars )
131     {
132         if( i_type != VLC_OBJECT_GLOBAL )
133             free( p_new );
134         return NULL;
135     }
136
137     if( i_type == VLC_OBJECT_GLOBAL )
138     {
139         /* If i_type is global, then p_new is actually p_libvlc_global */
140         p_new->p_libvlc_global = (libvlc_global_data_t*)p_new;
141         p_new->p_libvlc = NULL;
142
143         p_new->p_libvlc_global->i_counter = 0;
144         p_new->i_object_id = 0;
145
146         p_new->p_libvlc_global->i_objects = 1;
147         p_new->p_libvlc_global->pp_objects = malloc( sizeof(vlc_object_t *) );
148         p_new->p_libvlc_global->pp_objects[0] = p_new;
149         p_new->b_attached = VLC_TRUE;
150     }
151     else
152     {
153         p_new->p_libvlc_global = p_this->p_libvlc_global;
154         p_new->p_libvlc = ( i_type == VLC_OBJECT_LIBVLC ) ? (libvlc_int_t*)p_new
155                                                        : p_this->p_libvlc;
156
157         vlc_mutex_lock( &structure_lock );
158
159         p_new->p_libvlc_global->i_counter++;
160         p_new->i_object_id = p_new->p_libvlc_global->i_counter;
161
162         /* Wooohaa! If *this* fails, we're in serious trouble! Anyway it's
163          * useless to try and recover anything if pp_objects gets smashed. */
164         TAB_APPEND( p_new->p_libvlc_global->i_objects,
165                     p_new->p_libvlc_global->pp_objects,
166                     p_new );
167
168         vlc_mutex_unlock( &structure_lock );
169     }
170
171     p_new->i_refcount = 0;
172     p_new->p_parent = NULL;
173     p_new->pp_children = NULL;
174     p_new->i_children = 0;
175
176     p_new->p_private = NULL;
177
178     /* Initialize mutexes and condvars */
179     vlc_mutex_init( p_new, &p_new->object_lock );
180     vlc_cond_init( p_new, &p_new->object_wait );
181     vlc_mutex_init( p_new, &p_new->var_lock );
182
183     if( i_type == VLC_OBJECT_GLOBAL )
184     {
185         vlc_mutex_init( p_new, &structure_lock );
186
187         var_Create( p_new, "list", VLC_VAR_STRING | VLC_VAR_ISCOMMAND );
188         var_AddCallback( p_new, "list", DumpCommand, NULL );
189         var_Create( p_new, "tree", VLC_VAR_STRING | VLC_VAR_ISCOMMAND );
190         var_AddCallback( p_new, "tree", DumpCommand, NULL );
191         var_Create( p_new, "vars", VLC_VAR_STRING | VLC_VAR_ISCOMMAND );
192         var_AddCallback( p_new, "vars", DumpCommand, NULL );
193     }
194
195     return p_new;
196 }
197
198
199 /**
200  * Allocates and initializes a vlc object.
201  *
202  * @param i_type known object type (all of them are negative integer values),
203  *               or object byte size (always positive).
204  *
205  * @return the new object, or NULL on error.
206  */
207 void * __vlc_object_create( vlc_object_t *p_this, int i_type )
208 {
209     const char   * psz_type;
210     size_t         i_size;
211
212     switch( i_type )
213     {
214         case VLC_OBJECT_GLOBAL:
215             i_size = sizeof(libvlc_global_data_t);
216             psz_type = "global";
217             break;
218         case VLC_OBJECT_LIBVLC:
219             i_size = sizeof(libvlc_int_t);
220             psz_type = "libvlc";
221             break;
222         case VLC_OBJECT_MODULE:
223             i_size = sizeof(module_t);
224             psz_type = "module";
225             break;
226         case VLC_OBJECT_INTF:
227             i_size = sizeof(intf_thread_t);
228             psz_type = "interface";
229             break;
230         case VLC_OBJECT_DIALOGS:
231             i_size = sizeof(intf_thread_t);
232             psz_type = "dialogs";
233             break;
234         case VLC_OBJECT_PLAYLIST:
235             i_size = sizeof(playlist_t);
236             psz_type = "playlist";
237             break;
238         case VLC_OBJECT_SD:
239             i_size = sizeof(services_discovery_t);
240             psz_type = "services discovery";
241             break;
242         case VLC_OBJECT_INPUT:
243             i_size = sizeof(input_thread_t);
244             psz_type = "input";
245             break;
246         case VLC_OBJECT_DEMUX:
247             i_size = sizeof(demux_t);
248             psz_type = "demux";
249             break;
250         case VLC_OBJECT_STREAM:
251             i_size = sizeof(stream_t);
252             psz_type = "stream";
253             break;
254         case VLC_OBJECT_ACCESS:
255             i_size = sizeof(access_t);
256             psz_type = "access";
257             break;
258         case VLC_OBJECT_DECODER:
259             i_size = sizeof(decoder_t);
260             psz_type = "decoder";
261             break;
262         case VLC_OBJECT_PACKETIZER:
263             i_size = sizeof(decoder_t);
264             psz_type = "packetizer";
265             break;
266         case VLC_OBJECT_ENCODER:
267             i_size = sizeof(encoder_t);
268             psz_type = "encoder";
269             break;
270         case VLC_OBJECT_FILTER:
271             i_size = sizeof(filter_t);
272             psz_type = "filter";
273             break;
274         case VLC_OBJECT_VOUT:
275             i_size = sizeof(vout_thread_t);
276             psz_type = "video output";
277             break;
278         case VLC_OBJECT_SPU:
279             i_size = sizeof(spu_t);
280             psz_type = "subpicture";
281             break;
282         case VLC_OBJECT_AOUT:
283             i_size = sizeof(aout_instance_t);
284             psz_type = "audio output";
285             break;
286         case VLC_OBJECT_SOUT:
287             i_size = sizeof(sout_instance_t);
288             psz_type = "stream output";
289             break;
290         case VLC_OBJECT_VLM:
291             i_size = sizeof( vlm_t );
292             psz_type = "vlm dameon";
293             break;
294         case VLC_OBJECT_VOD:
295             i_size = sizeof( vod_t );
296             psz_type = "vod server";
297             break;
298         case VLC_OBJECT_TLS:
299             i_size = sizeof( tls_t );
300             psz_type = "tls";
301             break;
302         case VLC_OBJECT_XML:
303             i_size = sizeof( xml_t );
304             psz_type = "xml";
305             break;
306         case VLC_OBJECT_OPENGL:
307             i_size = sizeof( vout_thread_t );
308             psz_type = "opengl";
309             break;
310         case VLC_OBJECT_ANNOUNCE:
311             i_size = sizeof( announce_handler_t );
312             psz_type = "announce";
313             break;
314         case VLC_OBJECT_META_ENGINE:
315             i_size = sizeof( meta_engine_t );
316             psz_type = "meta engine";
317             break;
318         case VLC_OBJECT_OSDMENU:
319             i_size = sizeof( osd_menu_t );
320             psz_type = "osd menu";
321             break;
322         default:
323             i_size = i_type > (int)sizeof(vlc_object_t)
324                          ? i_type : (int)sizeof(vlc_object_t);
325             i_type = VLC_OBJECT_GENERIC;
326             psz_type = "generic";
327             break;
328     }
329
330     return vlc_custom_create( p_this, i_size, i_type, psz_type );
331 }
332
333
334 /**
335  ****************************************************************************
336  * Destroy a vlc object
337  *
338  * This function destroys an object that has been previously allocated with
339  * vlc_object_create. The object's refcount must be zero and it must not be
340  * attached to other objects in any way.
341  *****************************************************************************/
342 void __vlc_object_destroy( vlc_object_t *p_this )
343 {
344     int i_delay = 0;
345
346     if( p_this->i_children )
347     {
348         msg_Err( p_this, "cannot delete object (%i, %s) with children" ,
349                  p_this->i_object_id, p_this->psz_object_name );
350         return;
351     }
352
353     if( p_this->p_parent )
354     {
355         msg_Err( p_this, "cannot delete object (%i, %s) with a parent",
356                  p_this->i_object_id, p_this->psz_object_name );
357         return;
358     }
359
360     while( p_this->i_refcount )
361     {
362         i_delay++;
363
364         /* Don't warn immediately ... 100ms seems OK */
365         if( i_delay == 2 )
366         {
367             msg_Warn( p_this,
368                   "refcount is %i, delaying before deletion (id=%d,type=%d)",
369                   p_this->i_refcount, p_this->i_object_id,
370                   p_this->i_object_type );
371         }
372         else if( i_delay == 10 )
373         {
374             msg_Err( p_this,
375                   "refcount is %i, delaying again (id=%d,type=%d)",
376                   p_this->i_refcount, p_this->i_object_id,
377                   p_this->i_object_type );
378         }
379         else if( i_delay == 20 )
380         {
381             msg_Err( p_this,
382                   "waited too long, cancelling destruction (id=%d,type=%d)",
383                   p_this->i_object_id, p_this->i_object_type );
384             return;
385         }
386
387         msleep( 100000 );
388     }
389
390     /* Destroy the associated variables, starting from the end so that
391      * no memmove calls have to be done. */
392     while( p_this->i_vars )
393     {
394         var_Destroy( p_this, p_this->p_vars[p_this->i_vars - 1].psz_name );
395     }
396
397     free( p_this->p_vars );
398     vlc_mutex_destroy( &p_this->var_lock );
399
400     if( p_this->psz_header ) free( p_this->psz_header );
401
402     if( p_this->i_object_type == VLC_OBJECT_GLOBAL )
403     {
404         /* We are the global object ... no need to lock. */
405         free( p_this->p_libvlc_global->pp_objects );
406         p_this->p_libvlc_global->pp_objects = NULL;
407         p_this->p_libvlc_global->i_objects--;
408
409         vlc_mutex_destroy( &structure_lock );
410     }
411     else
412     {
413         int i_index;
414
415         vlc_mutex_lock( &structure_lock );
416
417         /* Wooohaa! If *this* fails, we're in serious trouble! Anyway it's
418          * useless to try and recover anything if pp_objects gets smashed. */
419         i_index = FindIndex( p_this, p_this->p_libvlc_global->pp_objects,
420                              p_this->p_libvlc_global->i_objects );
421         REMOVE_ELEM( p_this->p_libvlc_global->pp_objects,
422                      p_this->p_libvlc_global->i_objects, i_index );
423
424         vlc_mutex_unlock( &structure_lock );
425     }
426
427     vlc_mutex_destroy( &p_this->object_lock );
428     vlc_cond_destroy( &p_this->object_wait );
429
430     /* global is not dynamically allocated by vlc_object_create */
431     if( p_this->i_object_type != VLC_OBJECT_GLOBAL )
432     {
433         free( p_this );
434         p_this = NULL;
435     }
436 }
437
438 /**
439  * find an object given its ID
440  *
441  * This function looks for the object whose i_object_id field is i_id. We
442  * use a dichotomy so that lookups are in log2(n).
443  *****************************************************************************/
444 void * __vlc_object_get( vlc_object_t *p_this, int i_id )
445 {
446     int i_max, i_middle;
447     vlc_object_t **pp_objects;
448
449     vlc_mutex_lock( &structure_lock );
450
451     pp_objects = p_this->p_libvlc_global->pp_objects;
452
453     /* Perform our dichotomy */
454     for( i_max = p_this->p_libvlc_global->i_objects - 1 ; ; )
455     {
456         i_middle = i_max / 2;
457
458         if( pp_objects[i_middle]->i_object_id > i_id )
459         {
460             i_max = i_middle;
461         }
462         else if( pp_objects[i_middle]->i_object_id < i_id )
463         {
464             if( i_middle )
465             {
466                 pp_objects += i_middle;
467                 i_max -= i_middle;
468             }
469             else
470             {
471                 /* This happens when there are only two remaining objects */
472                 if( pp_objects[i_middle+1]->i_object_id == i_id )
473                 {
474                     vlc_mutex_unlock( &structure_lock );
475                     pp_objects[i_middle+1]->i_refcount++;
476                     return pp_objects[i_middle+1];
477                 }
478                 break;
479             }
480         }
481         else
482         {
483             vlc_mutex_unlock( &structure_lock );
484             pp_objects[i_middle]->i_refcount++;
485             return pp_objects[i_middle];
486         }
487
488         if( i_max == 0 )
489         {
490             /* this means that i_max == i_middle, and since we have already
491              * tested pp_objects[i_middle]), p_found is properly set. */
492             break;
493         }
494     }
495
496     vlc_mutex_unlock( &structure_lock );
497     return NULL;
498 }
499
500 /**
501  ****************************************************************************
502  * find a typed object and increment its refcount
503  *****************************************************************************
504  * This function recursively looks for a given object type. i_mode can be one
505  * of FIND_PARENT, FIND_CHILD or FIND_ANYWHERE.
506  *****************************************************************************/
507 void * __vlc_object_find( vlc_object_t *p_this, int i_type, int i_mode )
508 {
509     vlc_object_t *p_found;
510
511     vlc_mutex_lock( &structure_lock );
512
513     /* If we are of the requested type ourselves, don't look further */
514     if( !(i_mode & FIND_STRICT) && p_this->i_object_type == i_type )
515     {
516         p_this->i_refcount++;
517         vlc_mutex_unlock( &structure_lock );
518         return p_this;
519     }
520
521     /* Otherwise, recursively look for the object */
522     if( (i_mode & 0x000f) == FIND_ANYWHERE )
523     {
524         vlc_object_t *p_root = p_this;
525
526         /* Find the root */
527         while( p_root->p_parent != NULL &&
528                p_root != VLC_OBJECT( p_this->p_libvlc ) )
529         {
530             p_root = p_root->p_parent;
531         }
532
533         p_found = FindObject( p_root, i_type, (i_mode & ~0x000f)|FIND_CHILD );
534         if( p_found == NULL && p_root != VLC_OBJECT( p_this->p_libvlc ) )
535         {
536             p_found = FindObject( VLC_OBJECT( p_this->p_libvlc ),
537                                   i_type, (i_mode & ~0x000f)|FIND_CHILD );
538         }
539     }
540     else
541     {
542         p_found = FindObject( p_this, i_type, i_mode );
543     }
544
545     vlc_mutex_unlock( &structure_lock );
546
547     return p_found;
548 }
549
550 /**
551  ****************************************************************************
552  * increment an object refcount
553  *****************************************************************************/
554 void __vlc_object_yield( vlc_object_t *p_this )
555 {
556     vlc_mutex_lock( &structure_lock );
557     p_this->i_refcount++;
558     vlc_mutex_unlock( &structure_lock );
559 }
560
561 /**
562  ****************************************************************************
563  * decrement an object refcount
564  *****************************************************************************/
565 void __vlc_object_release( vlc_object_t *p_this )
566 {
567     vlc_mutex_lock( &structure_lock );
568     p_this->i_refcount--;
569     vlc_mutex_unlock( &structure_lock );
570 }
571
572 /**
573  ****************************************************************************
574  * attach object to a parent object
575  *****************************************************************************
576  * This function sets p_this as a child of p_parent, and p_parent as a parent
577  * of p_this. This link can be undone using vlc_object_detach.
578  *****************************************************************************/
579 void __vlc_object_attach( vlc_object_t *p_this, vlc_object_t *p_parent )
580 {
581     if( !p_this ) return;
582
583     vlc_mutex_lock( &structure_lock );
584
585     /* Attach the parent to its child */
586     p_this->p_parent = p_parent;
587
588     /* Attach the child to its parent */
589     INSERT_ELEM( p_parent->pp_children, p_parent->i_children,
590                  p_parent->i_children, p_this );
591
592     /* Climb up the tree to see whether we are connected with the root */
593     if( p_parent->b_attached )
594     {
595         SetAttachment( p_this, VLC_TRUE );
596     }
597
598     vlc_mutex_unlock( &structure_lock );
599 }
600
601 /**
602  ****************************************************************************
603  * detach object from its parent
604  *****************************************************************************
605  * This function removes all links between an object and its parent.
606  *****************************************************************************/
607 void __vlc_object_detach( vlc_object_t *p_this )
608 {
609     if( !p_this ) return;
610
611     vlc_mutex_lock( &structure_lock );
612     if( !p_this->p_parent )
613     {
614         msg_Err( p_this, "object is not attached" );
615         vlc_mutex_unlock( &structure_lock );
616         return;
617     }
618
619     /* Climb up the tree to see whether we are connected with the root */
620     if( p_this->p_parent->b_attached )
621     {
622         SetAttachment( p_this, VLC_FALSE );
623     }
624
625     DetachObject( p_this );
626     vlc_mutex_unlock( &structure_lock );
627     p_this = NULL;
628 }
629
630 /**
631  ****************************************************************************
632  * find a list typed objects and increment their refcount
633  *****************************************************************************
634  * This function recursively looks for a given object type. i_mode can be one
635  * of FIND_PARENT, FIND_CHILD or FIND_ANYWHERE.
636  *****************************************************************************/
637 vlc_list_t * __vlc_list_find( vlc_object_t *p_this, int i_type, int i_mode )
638 {
639     vlc_list_t *p_list;
640     vlc_object_t **pp_current, **pp_end;
641     int i_count = 0, i_index = 0;
642
643     vlc_mutex_lock( &structure_lock );
644
645     /* Look for the objects */
646     switch( i_mode & 0x000f )
647     {
648     case FIND_ANYWHERE:
649         pp_current = p_this->p_libvlc_global->pp_objects;
650         pp_end = pp_current + p_this->p_libvlc_global->i_objects;
651
652         for( ; pp_current < pp_end ; pp_current++ )
653         {
654             if( (*pp_current)->b_attached
655                  && (*pp_current)->i_object_type == i_type )
656             {
657                 i_count++;
658             }
659         }
660
661         p_list = NewList( i_count );
662         pp_current = p_this->p_libvlc_global->pp_objects;
663
664         for( ; pp_current < pp_end ; pp_current++ )
665         {
666             if( (*pp_current)->b_attached
667                  && (*pp_current)->i_object_type == i_type )
668             {
669                 ListReplace( p_list, *pp_current, i_index );
670                 if( i_index < i_count ) i_index++;
671             }
672         }
673     break;
674
675     case FIND_CHILD:
676         i_count = CountChildren( p_this, i_type );
677         p_list = NewList( i_count );
678
679         /* Check allocation was successful */
680         if( p_list->i_count != i_count )
681         {
682             msg_Err( p_this, "list allocation failed!" );
683             p_list->i_count = 0;
684             break;
685         }
686
687         p_list->i_count = 0;
688         ListChildren( p_list, p_this, i_type );
689         break;
690
691     default:
692         msg_Err( p_this, "unimplemented!" );
693         p_list = NewList( 0 );
694         break;
695     }
696
697     vlc_mutex_unlock( &structure_lock );
698
699     return p_list;
700 }
701
702 /*****************************************************************************
703  * DumpCommand: print the current vlc structure
704  *****************************************************************************
705  * This function prints either an ASCII tree showing the connections between
706  * vlc objects, and additional information such as their refcount, thread ID,
707  * etc. (command "tree"), or the same data as a simple list (command "list").
708  *****************************************************************************/
709 static int DumpCommand( vlc_object_t *p_this, char const *psz_cmd,
710                         vlc_value_t oldval, vlc_value_t newval, void *p_data )
711 {
712     if( *psz_cmd == 'l' )
713     {
714         vlc_mutex_lock( &structure_lock );
715
716         vlc_object_t **pp_current, **pp_end;
717
718         pp_current = p_this->p_libvlc_global->pp_objects;
719         pp_end = pp_current + p_this->p_libvlc_global->i_objects;
720
721         for( ; pp_current < pp_end ; pp_current++ )
722         {
723             if( (*pp_current)->b_attached )
724             {
725                 PrintObject( *pp_current, "" );
726             }
727             else
728             {
729                 printf( " o %.8i %s (not attached)\n",
730                         (*pp_current)->i_object_id,
731                         (*pp_current)->psz_object_type );
732             }
733         }
734
735         vlc_mutex_unlock( &structure_lock );
736     }
737     else
738     {
739         vlc_object_t *p_object = NULL;
740
741         if( *newval.psz_string )
742         {
743             p_object = vlc_object_get( p_this, atoi(newval.psz_string) );
744
745             if( !p_object )
746             {
747                 return VLC_ENOOBJ;
748             }
749         }
750
751         vlc_mutex_lock( &structure_lock );
752
753         if( *psz_cmd == 't' )
754         {
755             char psz_foo[2 * MAX_DUMPSTRUCTURE_DEPTH + 1];
756
757             if( !p_object )
758                 p_object = p_this->p_libvlc ? VLC_OBJECT(p_this->p_libvlc) : p_this;
759
760             psz_foo[0] = '|';
761             DumpStructure( p_object, 0, psz_foo );
762         }
763         else if( *psz_cmd == 'v' )
764         {
765             int i;
766
767             if( !p_object )
768                 p_object = p_this->p_libvlc ? VLC_OBJECT(p_this->p_libvlc) : p_this;
769
770             PrintObject( p_object, "" );
771
772             if( !p_object->i_vars )
773                 printf( " `-o No variables\n" );
774             for( i = 0; i < p_object->i_vars; i++ )
775             {
776                 variable_t *p_var = p_object->p_vars + i;
777
778                 const char *psz_type = "unknown";
779                 switch( p_var->i_type & VLC_VAR_TYPE )
780                 {
781 #define MYCASE( type, nice )                \
782                     case VLC_VAR_ ## type:  \
783                         psz_type = nice;    \
784                         break;
785                     MYCASE( VOID, "void" );
786                     MYCASE( BOOL, "bool" );
787                     MYCASE( INTEGER, "integer" );
788                     MYCASE( HOTKEY, "hotkey" );
789                     MYCASE( STRING, "string" );
790                     MYCASE( MODULE, "module" );
791                     MYCASE( FILE, "file" );
792                     MYCASE( DIRECTORY, "directory" );
793                     MYCASE( VARIABLE, "variable" );
794                     MYCASE( FLOAT, "float" );
795                     MYCASE( TIME, "time" );
796                     MYCASE( ADDRESS, "address" );
797                     MYCASE( MUTEX, "mutex" );
798                     MYCASE( LIST, "list" );
799 #undef MYCASE
800                 }
801                 printf( " %c-o \"%s\" (%s",
802                         i + 1 == p_object->i_vars ? '`' : '|',
803                         p_var->psz_name, psz_type );
804                 if( p_var->psz_text )
805                     printf( ", %s", p_var->psz_text );
806                 printf( ")" );
807                 if( p_var->i_type & VLC_VAR_ISCOMMAND )
808                     printf( ", command" );
809                 if( p_var->i_entries )
810                     printf( ", %d callbacks", p_var->i_entries );
811                 switch( p_var->i_type & 0x00f0 )
812                 {
813                     case VLC_VAR_VOID:
814                     case VLC_VAR_MUTEX:
815                         break;
816                     case VLC_VAR_BOOL:
817                         printf( ": %s", p_var->val.b_bool ? "true" : "false" );
818                         break;
819                     case VLC_VAR_INTEGER:
820                         printf( ": %d", p_var->val.i_int );
821                         break;
822                     case VLC_VAR_STRING:
823                         printf( ": \"%s\"", p_var->val.psz_string );
824                         break;
825                     case VLC_VAR_FLOAT:
826                         printf( ": %f", p_var->val.f_float );
827                         break;
828                     case VLC_VAR_TIME:
829                         printf( ": " I64Fi, p_var->val.i_time );
830                         break;
831                     case VLC_VAR_ADDRESS:
832                         printf( ": %p", p_var->val.p_address );
833                         break;
834                     case VLC_VAR_LIST:
835                         printf( ": TODO" );
836                         break;
837                 }
838                 printf( "\n" );
839             }
840         }
841
842         vlc_mutex_unlock( &structure_lock );
843
844         if( *newval.psz_string )
845         {
846             vlc_object_release( p_object );
847         }
848     }
849
850     return VLC_SUCCESS;
851 }
852
853 /*****************************************************************************
854  * vlc_list_release: free a list previously allocated by vlc_list_find
855  *****************************************************************************
856  * This function decreases the refcount of all objects in the list and
857  * frees the list.
858  *****************************************************************************/
859 void vlc_list_release( vlc_list_t *p_list )
860 {
861     int i_index;
862
863     vlc_mutex_lock( &structure_lock );
864     for( i_index = 0; i_index < p_list->i_count; i_index++ )
865     {
866         p_list->p_values[i_index].p_object->i_refcount--;
867     }
868     vlc_mutex_unlock( &structure_lock );
869
870     free( p_list->p_values );
871     free( p_list );
872 }
873
874 /* Following functions are local */
875
876 /*****************************************************************************
877  * FindIndex: find the index of an object in an array of objects
878  *****************************************************************************
879  * This function assumes that p_this can be found in pp_objects. It will not
880  * crash if p_this cannot be found, but will return a wrong value. It is your
881  * duty to check the return value if you are not certain that the object could
882  * be found for sure.
883  *****************************************************************************/
884 static int FindIndex( vlc_object_t *p_this,
885                       vlc_object_t **pp_objects, int i_count )
886 {
887     int i_middle = i_count / 2;
888
889     if( i_count == 0 )
890     {
891         return 0;
892     }
893
894     if( pp_objects[i_middle] == p_this )
895     {
896         return i_middle;
897     }
898
899     if( i_count == 1 )
900     {
901         return 0;
902     }
903
904     /* We take advantage of the sorted array */
905     if( pp_objects[i_middle]->i_object_id < p_this->i_object_id )
906     {
907         return i_middle + FindIndex( p_this, pp_objects + i_middle,
908                                              i_count - i_middle );
909     }
910     else
911     {
912         return FindIndex( p_this, pp_objects, i_middle );
913     }
914 }
915
916 static vlc_object_t * FindObject( vlc_object_t *p_this, int i_type, int i_mode )
917 {
918     int i;
919     vlc_object_t *p_tmp;
920
921     switch( i_mode & 0x000f )
922     {
923     case FIND_PARENT:
924         p_tmp = p_this->p_parent;
925         if( p_tmp )
926         {
927             if( p_tmp->i_object_type == i_type )
928             {
929                 p_tmp->i_refcount++;
930                 return p_tmp;
931             }
932             else
933             {
934                 return FindObject( p_tmp, i_type, i_mode );
935             }
936         }
937         break;
938
939     case FIND_CHILD:
940         for( i = p_this->i_children; i--; )
941         {
942             p_tmp = p_this->pp_children[i];
943             if( p_tmp->i_object_type == i_type )
944             {
945                 p_tmp->i_refcount++;
946                 return p_tmp;
947             }
948             else if( p_tmp->i_children )
949             {
950                 p_tmp = FindObject( p_tmp, i_type, i_mode );
951                 if( p_tmp )
952                 {
953                     return p_tmp;
954                 }
955             }
956         }
957         break;
958
959     case FIND_ANYWHERE:
960         /* Handled in vlc_object_find */
961         break;
962     }
963
964     return NULL;
965 }
966
967 static void DetachObject( vlc_object_t *p_this )
968 {
969     vlc_object_t *p_parent = p_this->p_parent;
970     int i_index, i;
971
972     /* Remove p_this's parent */
973     p_this->p_parent = NULL;
974
975     /* Remove all of p_parent's children which are p_this */
976     for( i_index = p_parent->i_children ; i_index-- ; )
977     {
978         if( p_parent->pp_children[i_index] == p_this )
979         {
980             p_parent->i_children--;
981             for( i = i_index ; i < p_parent->i_children ; i++ )
982             {
983                 p_parent->pp_children[i] = p_parent->pp_children[i+1];
984             }
985         }
986     }
987
988     if( p_parent->i_children )
989     {
990         p_parent->pp_children = (vlc_object_t **)realloc( p_parent->pp_children,
991                                p_parent->i_children * sizeof(vlc_object_t *) );
992     }
993     else
994     {
995         free( p_parent->pp_children );
996         p_parent->pp_children = NULL;
997     }
998 }
999
1000 /*****************************************************************************
1001  * SetAttachment: recursively set the b_attached flag of a subtree.
1002  *****************************************************************************
1003  * This function is used by the attach and detach functions to propagate
1004  * the b_attached flag in a subtree.
1005  *****************************************************************************/
1006 static void SetAttachment( vlc_object_t *p_this, vlc_bool_t b_attached )
1007 {
1008     int i_index;
1009
1010     for( i_index = p_this->i_children ; i_index-- ; )
1011     {
1012         SetAttachment( p_this->pp_children[i_index], b_attached );
1013     }
1014
1015     p_this->b_attached = b_attached;
1016 }
1017
1018 static void PrintObject( vlc_object_t *p_this, const char *psz_prefix )
1019 {
1020     char psz_children[20], psz_refcount[20], psz_thread[30], psz_name[50],
1021          psz_parent[20];
1022
1023     psz_name[0] = '\0';
1024     if( p_this->psz_object_name )
1025     {
1026         snprintf( psz_name, 49, " \"%s\"", p_this->psz_object_name );
1027         if( psz_name[48] )
1028             psz_name[48] = '\"';
1029     }
1030
1031     psz_children[0] = '\0';
1032     switch( p_this->i_children )
1033     {
1034         case 0:
1035             break;
1036         case 1:
1037             strcpy( psz_children, ", 1 child" );
1038             break;
1039         default:
1040             snprintf( psz_children, 19, ", %i children", p_this->i_children );
1041             break;
1042     }
1043
1044     psz_refcount[0] = '\0';
1045     if( p_this->i_refcount )
1046         snprintf( psz_refcount, 19, ", refcount %i", p_this->i_refcount );
1047
1048     psz_thread[0] = '\0';
1049     if( p_this->b_thread )
1050         snprintf( psz_thread, 29, " (thread %d)", (int)p_this->thread_id );
1051
1052     psz_parent[0] = '\0';
1053     if( p_this->p_parent )
1054         snprintf( psz_parent, 19, ", parent %i", p_this->p_parent->i_object_id );
1055
1056     printf( " %so %.8i %s%s%s%s%s%s\n", psz_prefix,
1057             p_this->i_object_id, p_this->psz_object_type,
1058             psz_name, psz_thread, psz_refcount, psz_children,
1059             psz_parent );
1060 }
1061
1062 static void DumpStructure( vlc_object_t *p_this, int i_level, char *psz_foo )
1063 {
1064     int i;
1065     char i_back = psz_foo[i_level];
1066     psz_foo[i_level] = '\0';
1067
1068     PrintObject( p_this, psz_foo );
1069
1070     psz_foo[i_level] = i_back;
1071
1072     if( i_level / 2 >= MAX_DUMPSTRUCTURE_DEPTH )
1073     {
1074         msg_Warn( p_this, "structure tree is too deep" );
1075         return;
1076     }
1077
1078     for( i = 0 ; i < p_this->i_children ; i++ )
1079     {
1080         if( i_level )
1081         {
1082             psz_foo[i_level-1] = ' ';
1083
1084             if( psz_foo[i_level-2] == '`' )
1085             {
1086                 psz_foo[i_level-2] = ' ';
1087             }
1088         }
1089
1090         if( i == p_this->i_children - 1 )
1091         {
1092             psz_foo[i_level] = '`';
1093         }
1094         else
1095         {
1096             psz_foo[i_level] = '|';
1097         }
1098
1099         psz_foo[i_level+1] = '-';
1100         psz_foo[i_level+2] = '\0';
1101
1102         DumpStructure( p_this->pp_children[i], i_level + 2, psz_foo );
1103     }
1104 }
1105
1106 static vlc_list_t * NewList( int i_count )
1107 {
1108     vlc_list_t * p_list = (vlc_list_t *)malloc( sizeof( vlc_list_t ) );
1109     if( p_list == NULL )
1110     {
1111         return NULL;
1112     }
1113
1114     p_list->i_count = i_count;
1115
1116     if( i_count == 0 )
1117     {
1118         p_list->p_values = NULL;
1119         return p_list;
1120     }
1121
1122     p_list->p_values = malloc( i_count * sizeof( vlc_value_t ) );
1123     if( p_list->p_values == NULL )
1124     {
1125         p_list->i_count = 0;
1126         return p_list;
1127     }
1128
1129     return p_list;
1130 }
1131
1132 static void ListReplace( vlc_list_t *p_list, vlc_object_t *p_object,
1133                          int i_index )
1134 {
1135     if( p_list == NULL || i_index >= p_list->i_count )
1136     {
1137         return;
1138     }
1139
1140     p_object->i_refcount++;
1141
1142     p_list->p_values[i_index].p_object = p_object;
1143
1144     return;
1145 }
1146
1147 /*static void ListAppend( vlc_list_t *p_list, vlc_object_t *p_object )
1148 {
1149     if( p_list == NULL )
1150     {
1151         return;
1152     }
1153
1154     p_list->p_values = realloc( p_list->p_values, (p_list->i_count + 1)
1155                                 * sizeof( vlc_value_t ) );
1156     if( p_list->p_values == NULL )
1157     {
1158         p_list->i_count = 0;
1159         return;
1160     }
1161
1162     p_object->i_refcount++;
1163
1164     p_list->p_values[p_list->i_count].p_object = p_object;
1165     p_list->i_count++;
1166
1167     return;
1168 }*/
1169
1170 static int CountChildren( vlc_object_t *p_this, int i_type )
1171 {
1172     vlc_object_t *p_tmp;
1173     int i, i_count = 0;
1174
1175     for( i = 0; i < p_this->i_children; i++ )
1176     {
1177         p_tmp = p_this->pp_children[i];
1178
1179         if( p_tmp->i_object_type == i_type )
1180         {
1181             i_count++;
1182         }
1183
1184         if( p_tmp->i_children )
1185         {
1186             i_count += CountChildren( p_tmp, i_type );
1187         }
1188     }
1189
1190     return i_count;
1191 }
1192
1193 static void ListChildren( vlc_list_t *p_list, vlc_object_t *p_this, int i_type )
1194 {
1195     vlc_object_t *p_tmp;
1196     int i;
1197
1198     for( i = 0; i < p_this->i_children; i++ )
1199     {
1200         p_tmp = p_this->pp_children[i];
1201
1202         if( p_tmp->i_object_type == i_type )
1203         {
1204             ListReplace( p_list, p_tmp, p_list->i_count++ );
1205         }
1206
1207         if( p_tmp->i_children )
1208         {
1209             ListChildren( p_list, p_tmp, i_type );
1210         }
1211     }
1212 }