git.sesse.net Git - vlc/blob - src/misc/objects.c

   1 /*****************************************************************************
   2  * objects.c: vlc_object_t handling
   3  *****************************************************************************
   4  * Copyright (C) 2002 VideoLAN
   5  * $Id: objects.c,v 1.19 2002/08/15 12:11:15 sam Exp $
   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., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  22  *****************************************************************************/
  23
  24 /*****************************************************************************
  25  * Preamble
  26  *****************************************************************************/
  27 #include <vlc/vlc.h>
  28
  29 #ifdef HAVE_STDLIB_H
  30 #   include <stdlib.h>                                          /* realloc() */
  31 #endif
  32
  33 #include "stream_control.h"
  34 #include "input_ext-intf.h"
  35 #include "input_ext-dec.h"
  36
  37 #include "video.h"
  38 #include "video_output.h"
  39
  40 #include "audio_output.h"
  41 #include "aout_internal.h"
  42
  43 #include "vlc_playlist.h"
  44 #include "interface.h"
  45
  46 /*****************************************************************************
  47  * Local prototypes
  48  *****************************************************************************/
  49 static vlc_object_t * FindObject    ( vlc_object_t *, int, int );
  50 static void           DetachObject  ( vlc_object_t * );
  51 static void           PrintObject   ( vlc_object_t *, const char * );
  52 static void           DumpStructure ( vlc_object_t *, int, char * );
  53 static int            FindIndex     ( vlc_object_t *, vlc_object_t **, int );
  54 static void           SetAttachment ( vlc_object_t *, vlc_bool_t );
  55
  56 static vlc_list_t *   NewList       ( void );
  57 static vlc_list_t *   ListAppend    ( vlc_list_t *, vlc_object_t * );
  58
  59 /*****************************************************************************
  60  * vlc_object_create: initialize a vlc object
  61  *****************************************************************************
  62  * This function allocates memory for a vlc object and initializes it. If
  63  * i_type is not a known value such as VLC_OBJECT_ROOT, VLC_OBJECT_VOUT and
  64  * so on, vlc_object_create will use its value for the object size.
  65  *****************************************************************************/
  66 void * __vlc_object_create( vlc_object_t *p_this, int i_type )
  67 {
  68     vlc_object_t * p_new;
  69     char *         psz_type;
  70     size_t         i_size;
  71
  72     switch( i_type )
  73     {
  74         case VLC_OBJECT_ROOT:
  75             i_size = sizeof(vlc_t);
  76             psz_type = "root";
  77             break;
  78         case VLC_OBJECT_MODULE:
  79             i_size = sizeof(module_t);
  80             psz_type = "module";
  81             break;
  82         case VLC_OBJECT_INTF:
  83             i_size = sizeof(intf_thread_t);
  84             psz_type = "interface";
  85             break;
  86         case VLC_OBJECT_PLAYLIST:
  87             i_size = sizeof(playlist_t);
  88             psz_type = "playlist";
  89             break;
  90         case VLC_OBJECT_INPUT:
  91             i_size = sizeof(input_thread_t);
  92             psz_type = "input";
  93             break;
  94         case VLC_OBJECT_DECODER:
  95             i_size = sizeof(decoder_fifo_t);
  96             psz_type = "decoder";
  97             break;
  98         case VLC_OBJECT_VOUT:
  99             i_size = sizeof(vout_thread_t);
 100             psz_type = "video output";
 101             break;
 102         case VLC_OBJECT_AOUT:
 103             i_size = sizeof(aout_instance_t);
 104             psz_type = "audio output";
 105             break;
 106         default:
 107             i_size = i_type > sizeof(vlc_object_t)
 108                    ? i_type : sizeof(vlc_object_t);
 109             i_type = VLC_OBJECT_GENERIC;
 110             psz_type = "generic";
 111             break;
 112     }
 113
 114     p_new = malloc( i_size );
 115
 116     if( !p_new )
 117     {
 118         return NULL;
 119     }
 120
 121     memset( p_new, 0, i_size );
 122
 123     p_new->i_object_type = i_type;
 124     p_new->psz_object_type = psz_type;
 125
 126     p_new->psz_object_name = NULL;
 127
 128     p_new->i_refcount = 0;
 129     p_new->b_die = VLC_FALSE;
 130     p_new->b_error = VLC_FALSE;
 131     p_new->b_dead = VLC_FALSE;
 132     p_new->b_attached = VLC_FALSE;
 133
 134     /* If i_type is root, then p_new is our own p_vlc */
 135     if( i_type == VLC_OBJECT_ROOT )
 136     {
 137         /* We are the first object ... no need to lock. */
 138         p_new->p_vlc = (vlc_t*)p_new;
 139
 140         p_new->p_vlc->i_counter = 0;
 141         p_new->i_object_id = 0;
 142
 143         p_new->p_vlc->i_objects = 1;
 144         p_new->p_vlc->pp_objects = malloc( sizeof(vlc_object_t *) );
 145         p_new->p_vlc->pp_objects[0] = p_new;
 146         p_new->b_attached = VLC_TRUE;
 147     }
 148     else
 149     {
 150         p_new->p_vlc = p_this->p_vlc;
 151
 152         vlc_mutex_lock( &p_this->p_vlc->structure_lock );
 153
 154         p_new->p_vlc->i_counter++;
 155         p_new->i_object_id = p_new->p_vlc->i_counter;
 156
 157         /* Wooohaa! If *this* fails, we're in serious trouble! Anyway it's
 158          * useless to try and recover anything if pp_objects gets smashed. */
 159         p_new->p_vlc->i_objects++;
 160         p_new->p_vlc->pp_objects =
 161                   realloc( p_new->p_vlc->pp_objects,
 162                            p_new->p_vlc->i_objects * sizeof(vlc_object_t *) );
 163         p_new->p_vlc->pp_objects[ p_new->p_vlc->i_objects - 1 ] = p_new;
 164
 165         vlc_mutex_unlock( &p_this->p_vlc->structure_lock );
 166     }
 167
 168     p_new->p_parent = NULL;
 169     p_new->pp_children = NULL;
 170     p_new->i_children = 0;
 171
 172     p_new->p_private = NULL;
 173
 174     vlc_mutex_init( p_new, &p_new->object_lock );
 175     vlc_cond_init( p_new, &p_new->object_wait );
 176
 177     return p_new;
 178 }
 179
 180 /*****************************************************************************
 181  * vlc_object_destroy: destroy a vlc object
 182  *****************************************************************************
 183  * This function destroys an object that has been previously allocated with
 184  * vlc_object_create. The object's refcount must be zero and it must not be
 185  * attached to other objects in any way.
 186  *****************************************************************************/
 187 void __vlc_object_destroy( vlc_object_t *p_this )
 188 {
 189     int i_delay = 0;
 190
 191     if( p_this->i_children )
 192     {
 193         msg_Err( p_this, "cannot delete object with children" );
 194         vlc_dumpstructure( p_this );
 195         return;
 196     }
 197
 198     if( p_this->p_parent )
 199     {
 200         msg_Err( p_this, "cannot delete object with a parent" );
 201         vlc_dumpstructure( p_this );
 202         return;
 203     }
 204
 205     while( p_this->i_refcount )
 206     {
 207         i_delay++;
 208
 209         /* Don't warn immediately ... 100ms seems OK */
 210         if( i_delay == 2 )
 211         {
 212             msg_Warn( p_this, "refcount is %i, delaying before deletion",
 213                               p_this->i_refcount );
 214         }
 215         else if( i_delay == 12 )
 216         {
 217             msg_Err( p_this, "refcount is %i, I have a bad feeling about this",
 218                              p_this->i_refcount );
 219         }
 220         else if( i_delay == 42 )
 221         {
 222             msg_Err( p_this, "we waited too long, cancelling destruction" );
 223             return;
 224         }
 225
 226         msleep( 100000 );
 227     }
 228
 229     vlc_mutex_lock( &p_this->p_vlc->structure_lock );
 230
 231     /* Wooohaa! If *this* fails, we're in serious trouble! Anyway it's
 232      * useless to try and recover anything if pp_objects gets smashed. */
 233     if( p_this->p_vlc->i_objects > 1 )
 234     {
 235         int i_index = FindIndex( p_this, p_this->p_vlc->pp_objects,
 236                                          p_this->p_vlc->i_objects );
 237         memmove( p_this->p_vlc->pp_objects + i_index,
 238                  p_this->p_vlc->pp_objects + i_index + 1,
 239                  (p_this->p_vlc->i_objects - i_index - 1)
 240                    * sizeof( vlc_object_t *) );
 241
 242         p_this->p_vlc->pp_objects =
 243             realloc( p_this->p_vlc->pp_objects,
 244                      (p_this->p_vlc->i_objects - 1) * sizeof(vlc_object_t *) );
 245     }
 246     else
 247     {
 248         free( p_this->p_vlc->pp_objects );
 249         p_this->p_vlc->pp_objects = NULL;
 250     }
 251
 252     p_this->p_vlc->i_objects--;
 253
 254     vlc_mutex_unlock( &p_this->p_vlc->structure_lock );
 255
 256     vlc_mutex_destroy( &p_this->object_lock );
 257     vlc_cond_destroy( &p_this->object_wait );
 258
 259     free( p_this );
 260 }
 261
 262 /*****************************************************************************
 263  * vlc_object_find: find a typed object and increment its refcount
 264  *****************************************************************************
 265  * This function recursively looks for a given object type. i_mode can be one
 266  * of FIND_PARENT, FIND_CHILD or FIND_ANYWHERE.
 267  *****************************************************************************/
 268 void * __vlc_object_find( vlc_object_t *p_this, int i_type, int i_mode )
 269 {
 270     vlc_object_t *p_found;
 271
 272     vlc_mutex_lock( &p_this->p_vlc->structure_lock );
 273
 274     /* If we are of the requested type ourselves, don't look further */
 275     if( !(i_mode & FIND_STRICT) && p_this->i_object_type == i_type )
 276     {
 277         p_this->i_refcount++;
 278         vlc_mutex_unlock( &p_this->p_vlc->structure_lock );
 279         return p_this;
 280     }
 281
 282     /* Otherwise, recursively look for the object */
 283     if( (i_mode & 0x000f) == FIND_ANYWHERE )
 284     {
 285         p_found = FindObject( VLC_OBJECT(p_this->p_vlc), i_type,
 286                               (i_mode & ~0x000f) | FIND_CHILD );
 287     }
 288     else
 289     {
 290         p_found = FindObject( p_this, i_type, i_mode );
 291     }
 292
 293     vlc_mutex_unlock( &p_this->p_vlc->structure_lock );
 294
 295     return p_found;
 296 }
 297
 298 /*****************************************************************************
 299  * vlc_object_yield: increment an object refcount
 300  *****************************************************************************/
 301 void __vlc_object_yield( vlc_object_t *p_this )
 302 {
 303     vlc_mutex_lock( &p_this->p_vlc->structure_lock );
 304     p_this->i_refcount++;
 305     vlc_mutex_unlock( &p_this->p_vlc->structure_lock );
 306 }
 307
 308 /*****************************************************************************
 309  * vlc_object_release: decrement an object refcount
 310  *****************************************************************************/
 311 void __vlc_object_release( vlc_object_t *p_this )
 312 {
 313     vlc_mutex_lock( &p_this->p_vlc->structure_lock );
 314     p_this->i_refcount--;
 315     vlc_mutex_unlock( &p_this->p_vlc->structure_lock );
 316 }
 317
 318 /*****************************************************************************
 319  * vlc_object_attach: attach object to a parent object
 320  *****************************************************************************
 321  * This function sets p_this as a child of p_parent, and p_parent as a parent
 322  * of p_this. This link can be undone using vlc_object_detach.
 323  *****************************************************************************/
 324 void __vlc_object_attach( vlc_object_t *p_this, vlc_object_t *p_parent )
 325 {
 326     vlc_mutex_lock( &p_this->p_vlc->structure_lock );
 327
 328     /* Attach the parent to its child */
 329     p_this->p_parent = p_parent;
 330
 331     /* Attach the child to its parent */
 332     p_parent->i_children++;
 333     p_parent->pp_children = (vlc_object_t **)realloc( p_parent->pp_children,
 334                                p_parent->i_children * sizeof(vlc_object_t *) );
 335     p_parent->pp_children[p_parent->i_children - 1] = p_this;
 336
 337     /* Climb up the tree to see whether we are connected with the root */
 338     if( p_parent->b_attached )
 339     {
 340         SetAttachment( p_this, VLC_TRUE );
 341     }
 342
 343     vlc_mutex_unlock( &p_this->p_vlc->structure_lock );
 344 }
 345
 346 /*****************************************************************************
 347  * vlc_object_detach: detach object from its parent
 348  *****************************************************************************
 349  * This function removes all links between an object and its parent.
 350  *****************************************************************************/
 351 void __vlc_object_detach( vlc_object_t *p_this )
 352 {
 353     vlc_mutex_lock( &p_this->p_vlc->structure_lock );
 354     if( !p_this->p_parent )
 355     {
 356         msg_Err( p_this, "object is not attached" );
 357         vlc_mutex_unlock( &p_this->p_vlc->structure_lock );
 358         return;
 359     }
 360
 361     /* Climb up the tree to see whether we are connected with the root */
 362     if( p_this->p_parent->b_attached )
 363     {
 364         SetAttachment( p_this, VLC_FALSE );
 365     }
 366
 367     DetachObject( p_this );
 368     vlc_mutex_unlock( &p_this->p_vlc->structure_lock );
 369 }
 370
 371 /*****************************************************************************
 372  * vlc_list_find: find a list typed objects and increment their refcount
 373  *****************************************************************************
 374  * This function recursively looks for a given object type. i_mode can be one
 375  * of FIND_PARENT, FIND_CHILD or FIND_ANYWHERE.
 376  *****************************************************************************/
 377 vlc_list_t * __vlc_list_find( vlc_object_t *p_this, int i_type, int i_mode )
 378 {
 379     vlc_list_t *p_list = NewList();
 380
 381     vlc_mutex_lock( &p_this->p_vlc->structure_lock );
 382
 383     /* Look for the objects */
 384     if( (i_mode & 0x000f) == FIND_ANYWHERE )
 385     {
 386         vlc_object_t **pp_current, **pp_end;
 387
 388         pp_current = p_this->p_vlc->pp_objects;
 389         pp_end = pp_current + p_this->p_vlc->i_objects;
 390
 391         for( ; pp_current < pp_end ; pp_current++ )
 392         {
 393             if( (*pp_current)->b_attached
 394                  && (*pp_current)->i_object_type == i_type )
 395             {
 396                 p_list = ListAppend( p_list, *pp_current );
 397             }
 398         }
 399     }
 400     else
 401     {
 402         msg_Err( p_this, "unimplemented!" );
 403     }
 404
 405     vlc_mutex_unlock( &p_this->p_vlc->structure_lock );
 406
 407     return p_list;
 408 }
 409
 410 /*****************************************************************************
 411  * vlc_liststructure: print the current vlc objects
 412  *****************************************************************************
 413  * This function prints alist of vlc objects, and additional information such
 414  * as their refcount, thread ID, etc.
 415  *****************************************************************************/
 416 void __vlc_liststructure( vlc_object_t *p_this )
 417 {
 418     vlc_object_t **pp_current, **pp_end;
 419
 420     vlc_mutex_lock( &p_this->p_vlc->structure_lock );
 421
 422     pp_current = p_this->p_vlc->pp_objects;
 423     pp_end = pp_current + p_this->p_vlc->i_objects;
 424
 425     for( ; pp_current < pp_end ; pp_current++ )
 426     {
 427         if( (*pp_current)->b_attached )
 428         {
 429             PrintObject( *pp_current, "" );
 430         }
 431         else
 432         {
 433             msg_Info( p_this->p_vlc, "o %.6x %s (not attached)",
 434                       (*pp_current)->i_object_id,
 435                       (*pp_current)->psz_object_type );
 436         }
 437     }
 438
 439     vlc_mutex_unlock( &p_this->p_vlc->structure_lock );
 440 }
 441
 442 /*****************************************************************************
 443  * vlc_dumpstructure: print the current vlc structure
 444  *****************************************************************************
 445  * This function prints an ASCII tree showing the connections between vlc
 446  * objects, and additional information such as their refcount, thread ID, etc.
 447  *****************************************************************************/
 448 void __vlc_dumpstructure( vlc_object_t *p_this )
 449 {
 450     char psz_foo[2 * MAX_DUMPSTRUCTURE_DEPTH + 1];
 451
 452     vlc_mutex_lock( &p_this->p_vlc->structure_lock );
 453     psz_foo[0] = '|';
 454     DumpStructure( p_this, 0, psz_foo );
 455     vlc_mutex_unlock( &p_this->p_vlc->structure_lock );
 456 }
 457
 458 /*****************************************************************************
 459  * vlc_list_release: free a list previously allocated by vlc_list_find
 460  *****************************************************************************
 461  * This function decreases the refcount of all objects in the list and
 462  * frees the list.
 463  *****************************************************************************/
 464 void vlc_list_release( vlc_list_t *p_list )
 465 {
 466     if( p_list->i_count )
 467     {
 468         vlc_t *         p_vlc = p_list->pp_objects[0]->p_vlc;
 469         vlc_object_t ** pp_current = p_list->pp_objects;
 470
 471         vlc_mutex_lock( &p_vlc->structure_lock );
 472
 473         while( pp_current[0] )
 474         {
 475             pp_current[0]->i_refcount--;
 476             pp_current++;
 477         }
 478
 479         vlc_mutex_unlock( &p_vlc->structure_lock );
 480     }
 481
 482     free( p_list );
 483 }
 484
 485 /* Following functions are local */
 486
 487 /*****************************************************************************
 488  * FindIndex: find the index of an object in an array of objects
 489  *****************************************************************************
 490  * This function assumes that p_this can be found in pp_objects. It will not
 491  * crash if p_this cannot be found, but will return a wrong value. It is your
 492  * duty to check the return value if you are not certain that the object could
 493  * be found for sure.
 494  *****************************************************************************/
 495 static int FindIndex( vlc_object_t *p_this,
 496                       vlc_object_t **pp_objects, int i_count )
 497 {
 498     int i_middle = i_count / 2;
 499
 500     if( i_count == 0 )
 501     {
 502         return 0;
 503     }
 504
 505     if( pp_objects[i_middle] == p_this )
 506     {
 507         return i_middle;
 508     }
 509
 510     if( i_count == 1 )
 511     {
 512         return 0;
 513     }
 514
 515     /* We take advantage of the sorted array */
 516     if( pp_objects[i_middle]->i_object_id < p_this->i_object_id )
 517     {
 518         return i_middle + FindIndex( p_this, pp_objects + i_middle,
 519                                              i_count - i_middle );
 520     }
 521     else
 522     {
 523         return FindIndex( p_this, pp_objects, i_middle );
 524     }
 525 }
 526
 527 static vlc_object_t * FindObject( vlc_object_t *p_this, int i_type, int i_mode )
 528 {
 529     int i;
 530     vlc_object_t *p_tmp;
 531
 532     switch( i_mode & 0x000f )
 533     {
 534     case FIND_PARENT:
 535         p_tmp = p_this->p_parent;
 536         if( p_tmp )
 537         {
 538             if( p_tmp->i_object_type == i_type )
 539             {
 540                 p_tmp->i_refcount++;
 541                 return p_tmp;
 542             }
 543             else
 544             {
 545                 return FindObject( p_tmp, i_type, i_mode );
 546             }
 547         }
 548         break;
 549
 550     case FIND_CHILD:
 551         for( i = p_this->i_children; i--; )
 552         {
 553             p_tmp = p_this->pp_children[i];
 554             if( p_tmp->i_object_type == i_type )
 555             {
 556                 p_tmp->i_refcount++;
 557                 return p_tmp;
 558             }
 559             else if( p_tmp->i_children )
 560             {
 561                 p_tmp = FindObject( p_tmp, i_type, i_mode );
 562                 if( p_tmp )
 563                 {
 564                     return p_tmp;
 565                 }
 566             }
 567         }
 568         break;
 569
 570     case FIND_ANYWHERE:
 571         /* Handled in vlc_object_find */
 572         break;
 573     }
 574
 575     return NULL;
 576 }
 577
 578 static void DetachObject( vlc_object_t *p_this )
 579 {
 580     vlc_object_t *p_parent = p_this->p_parent;
 581     int i_index, i;
 582
 583     /* Remove p_this's parent */
 584     p_this->p_parent = NULL;
 585
 586     /* Remove all of p_parent's children which are p_this */
 587     for( i_index = p_parent->i_children ; i_index-- ; )
 588     {
 589         if( p_parent->pp_children[i_index] == p_this )
 590         {
 591             p_parent->i_children--;
 592             for( i = i_index ; i < p_parent->i_children ; i++ )
 593             {
 594                 p_parent->pp_children[i] = p_parent->pp_children[i+1];
 595             }
 596         }
 597     }
 598
 599     if( p_parent->i_children )
 600     {
 601         p_parent->pp_children = (vlc_object_t **)realloc( p_parent->pp_children,
 602                                p_parent->i_children * sizeof(vlc_object_t *) );
 603     }
 604     else
 605     {
 606         free( p_parent->pp_children );
 607         p_parent->pp_children = NULL;
 608     }
 609 }
 610
 611 /*****************************************************************************
 612  * SetAttachment: recursively set the b_attached flag of a subtree.
 613  *****************************************************************************
 614  * This function is used by the attach and detach functions to propagate
 615  * the b_attached flag in a subtree.
 616  *****************************************************************************/
 617 static void SetAttachment( vlc_object_t *p_this, vlc_bool_t b_attached )
 618 {
 619     int i_index;
 620
 621     for( i_index = p_this->i_children ; i_index-- ; )
 622     {
 623         SetAttachment( p_this->pp_children[i_index], b_attached );
 624     }
 625
 626     p_this->b_attached = b_attached;
 627 }
 628
 629 static void PrintObject( vlc_object_t *p_this, const char *psz_prefix )
 630 {
 631     char psz_children[20], psz_refcount[20], psz_thread[20], psz_name[50];
 632
 633     psz_name[0] = '\0';
 634     if( p_this->psz_object_name )
 635     {
 636         snprintf( psz_name, 50, " \"%s\"", p_this->psz_object_name );
 637         psz_name[48] = '\"';
 638         psz_name[49] = '\0';
 639     }
 640
 641     psz_children[0] = '\0';
 642     switch( p_this->i_children )
 643     {
 644         case 0:
 645             break;
 646         case 1:
 647             strcpy( psz_children, ", 1 child" );
 648             break;
 649         default:
 650             snprintf( psz_children, 20,
 651                       ", %i children", p_this->i_children );
 652             psz_children[19] = '\0';
 653             break;
 654     }
 655
 656     psz_refcount[0] = '\0';
 657     if( p_this->i_refcount )
 658     {
 659         snprintf( psz_refcount, 20, ", refcount %i", p_this->i_refcount );
 660         psz_refcount[19] = '\0';
 661     }
 662
 663     psz_thread[0] = '\0';
 664     if( p_this->b_thread )
 665     {
 666         snprintf( psz_thread, 20, " (thread %d)", (int)p_this->thread_id );
 667         psz_thread[19] = '\0';
 668     }
 669
 670     msg_Info( p_this->p_vlc, "%so %.6x %s%s%s%s%s", psz_prefix,
 671               p_this->i_object_id, p_this->psz_object_type,
 672               psz_name, psz_thread, psz_refcount, psz_children );
 673 }
 674
 675 static void DumpStructure( vlc_object_t *p_this, int i_level, char *psz_foo )
 676 {
 677     int i;
 678     char i_back = psz_foo[i_level];
 679     psz_foo[i_level] = '\0';
 680
 681     PrintObject( p_this, psz_foo );
 682
 683     psz_foo[i_level] = i_back;
 684
 685     if( i_level / 2 >= MAX_DUMPSTRUCTURE_DEPTH )
 686     {
 687         msg_Warn( p_this, "structure tree is too deep" );
 688         return;
 689     }
 690
 691     for( i = 0 ; i < p_this->i_children ; i++ )
 692     {
 693         if( i_level )
 694         {
 695             psz_foo[i_level-1] = ' ';
 696
 697             if( psz_foo[i_level-2] == '`' )
 698             {
 699                 psz_foo[i_level-2] = ' ';
 700             }
 701         }
 702
 703         if( i == p_this->i_children - 1 )
 704         {
 705             psz_foo[i_level] = '`';
 706         }
 707         else
 708         {
 709             psz_foo[i_level] = '|';
 710         }
 711
 712         psz_foo[i_level+1] = '-';
 713         psz_foo[i_level+2] = '\0';
 714
 715         DumpStructure( p_this->pp_children[i], i_level + 2, psz_foo );
 716     }
 717 }
 718
 719 static vlc_list_t * NewList( void )
 720 {
 721     vlc_list_t *p_list = malloc( sizeof( vlc_list_t )
 722                                      + 3 * sizeof( vlc_object_t * ) );
 723
 724     if( p_list == NULL )
 725     {
 726         return NULL;
 727     }
 728
 729     p_list->i_count = 0;
 730     p_list->pp_objects = &p_list->_p_first;
 731
 732     /* We allocated space for NULL and for three extra objects */
 733     p_list->_i_extra = 3;
 734     p_list->_p_first = NULL;
 735
 736     return p_list;
 737 }
 738
 739 static vlc_list_t * ListAppend( vlc_list_t *p_list, vlc_object_t *p_object )
 740 {
 741     if( p_list == NULL )
 742     {
 743         return NULL;
 744     }
 745
 746     if( p_list->_i_extra == 0 )
 747     {
 748         /* If we had X objects it means the array has a size of X+1, we
 749          * make it size 2X+2, so we alloc 2X+1 because there is already
 750          * one allocated in the real structure */
 751         p_list = realloc( p_list, sizeof( vlc_list_t )
 752                                    + (p_list->i_count * 2 + 1)
 753                                        * sizeof( vlc_object_t * ) );
 754         if( p_list == NULL )
 755         {
 756             return NULL;
 757         }
 758
 759         /* We have X+1 extra slots */
 760         p_list->_i_extra = p_list->i_count + 1;
 761         p_list->pp_objects = &p_list->_p_first;
 762     }
 763
 764     p_object->i_refcount++;
 765
 766     p_list->pp_objects[p_list->i_count] = p_object;
 767     p_list->i_count++;
 768     p_list->pp_objects[p_list->i_count] = NULL;
 769     p_list->_i_extra--;
 770
 771     return p_list;
 772 }
 773