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

   1 /*****************************************************************************
   2  * stats.c: Statistics handling
   3  *****************************************************************************
   4  * Copyright (C) 2006 the VideoLAN team
   5  * $Id$
   6  *
   7  * Authors: Clément Stenac <zorglub@videolan.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  * Preamble
  26  *****************************************************************************/
  27 #include <stdio.h>                                               /* required */
  28
  29 #include <vlc/vlc.h>
  30 #include <vlc_input.h>
  31
  32 /*****************************************************************************
  33  * Local prototypes
  34  *****************************************************************************/
  35 static counter_t *GetCounter( stats_handler_t *p_handler, int i_object_id,
  36                               const char *psz_name );
  37 static int stats_CounterUpdate( stats_handler_t *p_handler,
  38                                 counter_t *p_counter,
  39                                 vlc_value_t val );
  40 static stats_handler_t* stats_HandlerCreate( vlc_object_t *p_this );
  41 static stats_handler_t *stats_HandlerGet( vlc_object_t *p_this );
  42
  43 /*****************************************************************************
  44  * Exported functions
  45  *****************************************************************************/
  46
  47 /**
  48  * Cleanup statistics handler stuff
  49  * \param p_stats the handler to clean
  50  * \return nothing
  51  */
  52 void stats_HandlerDestroy( stats_handler_t *p_stats )
  53 {
  54     int i;
  55     for ( i =  p_stats->i_counters - 1 ; i >= 0 ; i-- )
  56     {
  57         int j;
  58         counter_t * p_counter = p_stats->pp_counters[i];
  59
  60         for( j = p_counter->i_samples -1; j >= 0 ; j-- )
  61         {
  62             counter_sample_t *p_sample = p_counter->pp_samples[j];
  63             REMOVE_ELEM( p_counter->pp_samples, p_counter->i_samples, j );
  64             free( p_sample );
  65         }
  66         free( p_counter->psz_name );
  67         REMOVE_ELEM( p_stats->pp_counters, p_stats->i_counters, i );
  68         free( p_counter );
  69     }
  70 }
  71
  72 /**
  73  * Create a statistics counter
  74  * \param p_this the object for which to create the counter
  75  * \param psz_name the name
  76  * \param i_type the type of stored data. One of VLC_VAR_STRING,
  77  * VLC_VAR_INTEGER, VLC_VAR_FLOAT
  78  * \param i_compute_type the aggregation type. One of STATS_LAST (always
  79  * keep the last value), STATS_COUNTER (increment by the passed value),
  80  * STATS_MAX (keep the maximum passed value), STATS_MIN, or STATS_DERIVATIVE
  81  * (keep a time derivative of the value)
  82  */
  83 int __stats_Create( vlc_object_t *p_this, const char *psz_name, int i_type,
  84                     int i_compute_type )
  85 {
  86     counter_t *p_counter;
  87     stats_handler_t *p_handler;
  88
  89     if( p_this->p_libvlc->b_stats == VLC_FALSE )
  90     {
  91         return VLC_EGENERIC;
  92     }
  93     p_handler = stats_HandlerGet( p_this );
  94     if( !p_handler ) return VLC_ENOMEM;
  95
  96     vlc_mutex_lock( &p_handler->object_lock );
  97
  98     p_counter = (counter_t*) malloc( sizeof( counter_t ) ) ;
  99
 100     p_counter->psz_name = strdup( psz_name );
 101     p_counter->i_source_object = p_this->i_object_id;
 102     p_counter->i_compute_type = i_compute_type;
 103     p_counter->i_type = i_type;
 104     p_counter->i_samples = 0;
 105     p_counter->pp_samples = NULL;
 106
 107     p_counter->update_interval = 0;
 108     p_counter->last_update = 0;
 109
 110     INSERT_ELEM( p_handler->pp_counters,
 111                  p_handler->i_counters,
 112                  p_handler->i_counters,
 113                  p_counter );
 114
 115     vlc_mutex_unlock( &p_handler->object_lock );
 116
 117     return VLC_SUCCESS;
 118 }
 119
 120 /** Update a counter element with new values
 121  * \param p_this the object in which to update
 122  * \param psz_name the name
 123  * \param val the vlc_value union containing the new value to aggregate. For
 124  * more information on how data is aggregated, \see __stats_Create
 125  */
 126 int __stats_Update( vlc_object_t *p_this, const char *psz_name,
 127                     vlc_value_t val )
 128 {
 129     int i_ret;
 130     counter_t *p_counter;
 131
 132     /* Get stats handler singleton */
 133     stats_handler_t *p_handler;
 134     if( p_this->p_libvlc->b_stats == VLC_FALSE )
 135     {
 136         return VLC_EGENERIC;
 137     }
 138     p_handler = stats_HandlerGet( p_this );
 139     if( !p_handler ) return VLC_ENOMEM;
 140
 141     vlc_mutex_lock( &p_handler->object_lock );
 142     /* Look for existing element */
 143     p_counter = GetCounter( p_handler, p_this->i_object_id,
 144                             psz_name );
 145     if( !p_counter )
 146     {
 147         vlc_mutex_unlock( &p_handler->object_lock );
 148         vlc_object_release( p_handler );
 149         return VLC_ENOOBJ;
 150     }
 151
 152     i_ret = stats_CounterUpdate( p_handler, p_counter, val );
 153     vlc_mutex_unlock( &p_handler->object_lock );
 154
 155     return i_ret;
 156 }
 157
 158 /** Get the aggregated value for a counter
 159  * \param p_this an object
 160  * \param i_object_id the object id from which we want the data
 161  * \param psz_name the name of the couner
 162  * \param val a pointer to an initialized vlc_value union. It will contain the
 163  * retrieved value
 164  * \return an error code
 165  */
 166 int __stats_Get( vlc_object_t *p_this, int i_object_id,
 167                  const char *psz_name, vlc_value_t *val )
 168 {
 169     counter_t *p_counter;
 170
 171     /* Get stats handler singleton */
 172     stats_handler_t *p_handler;
 173     if( p_this->p_libvlc->b_stats == VLC_FALSE )
 174     {
 175         return VLC_EGENERIC;
 176     }
 177     p_handler = stats_HandlerGet( p_this );
 178     if( !p_handler ) return VLC_ENOMEM;
 179     vlc_mutex_lock( &p_handler->object_lock );
 180
 181     /* Look for existing element */
 182     p_counter = GetCounter( p_handler, i_object_id,
 183                             psz_name );
 184     if( !p_counter )
 185     {
 186         vlc_mutex_unlock( &p_handler->object_lock );
 187         vlc_object_release( p_handler );
 188         val->i_int = val->f_float = 0.0;
 189         return VLC_ENOOBJ;
 190     }
 191
 192     if( p_counter->i_samples == 0 )
 193     {
 194         vlc_mutex_unlock( &p_handler->object_lock );
 195         val->i_int = val->f_float = 0.0;
 196         return VLC_EGENERIC;
 197     }
 198
 199     switch( p_counter->i_compute_type )
 200     {
 201     case STATS_LAST:
 202     case STATS_MIN:
 203     case STATS_MAX:
 204     case STATS_COUNTER:
 205         *val = p_counter->pp_samples[0]->value;
 206         break;
 207     case STATS_DERIVATIVE:
 208         /* Not ready yet */
 209         if( p_counter->i_samples < 2 )
 210         {
 211             vlc_mutex_unlock( &p_handler->object_lock );
 212             val->i_int = 0; val->f_float = 0.0;
 213             return VLC_EGENERIC;
 214         }
 215         if( p_counter->i_type == VLC_VAR_INTEGER )
 216         {
 217             float f = ( p_counter->pp_samples[0]->value.i_int -
 218                         p_counter->pp_samples[1]->value.i_int ) /
 219                     (float)(  p_counter->pp_samples[0]->date -
 220                               p_counter->pp_samples[1]->date );
 221             val->i_int = (int)f;
 222         }
 223         else
 224         {
 225             float f = (float)( p_counter->pp_samples[0]->value.f_float -
 226                                p_counter->pp_samples[1]->value.f_float ) /
 227                       (float)( p_counter->pp_samples[0]->date -
 228                                p_counter->pp_samples[1]->date );
 229             val->f_float = f;
 230         }
 231         break;
 232     }
 233     vlc_object_release( p_handler );
 234
 235     vlc_mutex_unlock( &p_handler->object_lock );
 236     return VLC_SUCCESS;;
 237 }
 238
 239 /** Get a statistics counter structure. This allows for low-level modifications
 240  * \param p_this a parent object
 241  * \param i_object_id the object from which to retrieve data
 242  * \param psz_name the name
 243  * \return the counter, or NULL if not found (or handler not created yet)
 244  */
 245 counter_t *__stats_CounterGet( vlc_object_t *p_this, int i_object_id,
 246                                const char *psz_name )
 247 {
 248     counter_t *p_counter;
 249
 250     stats_handler_t *p_handler;
 251     if( p_this->p_libvlc->b_stats == VLC_FALSE )
 252     {
 253         return NULL;
 254     }
 255     p_handler = stats_HandlerGet( p_this );
 256     if( !p_handler ) return NULL;
 257
 258     vlc_mutex_lock( &p_handler->object_lock );
 259
 260     /* Look for existing element */
 261     p_counter = GetCounter( p_handler, i_object_id,
 262                             psz_name );
 263     vlc_mutex_unlock( &p_handler->object_lock );
 264     vlc_object_release( p_handler );
 265
 266     return p_counter;
 267 }
 268
 269
 270 void stats_ComputeInputStats( input_thread_t *p_input,
 271                               input_stats_t *p_stats )
 272 {
 273     vlc_object_t *p_obj;
 274     vlc_list_t *p_list;
 275     int i_index;
 276     vlc_mutex_lock( &p_stats->lock );
 277
 278     /* Input */
 279     stats_GetInteger( p_input, p_input->i_object_id, "read_packets",
 280                        &p_stats->i_read_packets );
 281     stats_GetInteger( p_input, p_input->i_object_id, "read_bytes",
 282                        &p_stats->i_read_bytes );
 283     stats_GetFloat( p_input, p_input->i_object_id, "input_bitrate",
 284                        &p_stats->f_input_bitrate );
 285
 286     stats_GetInteger( p_input, p_input->i_object_id, "demux_read",
 287                       &p_stats->i_demux_read_bytes );
 288     stats_GetFloat( p_input, p_input->i_object_id, "demux_bitrate",
 289                       &p_stats->f_demux_bitrate );
 290
 291     stats_GetInteger( p_input, p_input->i_object_id, "decoded_video",
 292                       &p_stats->i_decoded_video );
 293     stats_GetInteger( p_input, p_input->i_object_id, "decoded_audio",
 294                       &p_stats->i_decoded_audio );
 295
 296     /* Sout */
 297     stats_GetInteger( p_input, p_input->i_object_id, "sout_sent_packets",
 298                       &p_stats->i_sent_packets );
 299     stats_GetInteger( p_input, p_input->i_object_id, "sout_sent_bytes",
 300                       &p_stats->i_sent_bytes );
 301     stats_GetFloat  ( p_input, p_input->i_object_id, "sout_send_bitrate",
 302                       &p_stats->f_send_bitrate );
 303
 304     /* Aout - We store in p_input because aout is shared */
 305     stats_GetInteger( p_input, p_input->i_object_id, "played_abuffers",
 306                       &p_stats->i_played_abuffers );
 307     stats_GetInteger( p_input, p_input->i_object_id, "lost_abuffers",
 308                       &p_stats->i_lost_abuffers );
 309
 310     /* Vouts - FIXME: Store all in input */
 311     p_list = vlc_list_find( p_input, VLC_OBJECT_VOUT, FIND_CHILD );
 312     if( p_list )
 313     {
 314         p_stats->i_displayed_pictures  = 0 ;
 315         p_stats->i_lost_pictures = 0;
 316         for( i_index = 0; i_index < p_list->i_count ; i_index ++ )
 317         {
 318             int i_displayed = 0, i_lost = 0;
 319             p_obj = (vlc_object_t *)p_list->p_values[i_index].p_object;
 320             stats_GetInteger( p_obj, p_obj->i_object_id, "displayed_pictures",
 321                               &i_displayed );
 322             stats_GetInteger( p_obj, p_obj->i_object_id, "lost_pictures",
 323                               &i_lost );
 324             p_stats->i_displayed_pictures += i_displayed;
 325             p_stats->i_lost_pictures += i_lost;
 326          }
 327         vlc_list_release( p_list );
 328     }
 329
 330     vlc_mutex_unlock( &p_stats->lock );
 331 }
 332
 333
 334 void stats_ReinitInputStats( input_stats_t *p_stats )
 335 {
 336     p_stats->i_read_packets = p_stats->i_read_bytes =
 337     p_stats->f_input_bitrate = p_stats->f_average_input_bitrate =
 338     p_stats->i_demux_read_packets = p_stats->i_demux_read_bytes =
 339     p_stats->f_demux_bitrate = p_stats->f_average_demux_bitrate =
 340     p_stats->i_displayed_pictures = p_stats->i_lost_pictures =
 341     p_stats->i_played_abuffers = p_stats->i_lost_abuffers =
 342     p_stats->i_decoded_video = p_stats->i_decoded_audio =
 343     p_stats->i_sent_bytes = p_stats->i_sent_packets = p_stats->f_send_bitrate
 344      = 0;
 345 }
 346
 347 void stats_DumpInputStats( input_stats_t *p_stats  )
 348 {
 349     vlc_mutex_lock( &p_stats->lock );
 350     /* f_bitrate is in bytes / microsecond
 351      * *1000 => bytes / millisecond => kbytes / seconds */
 352     fprintf( stderr, "Input : %i (%i bytes) - %f kB/s - Demux : %i (%i bytes) - %f kB/s\n"
 353                      " - Vout : %i/%i - Aout : %i/%i - Vout : %f\n",
 354                     p_stats->i_read_packets, p_stats->i_read_bytes,
 355                     p_stats->f_input_bitrate * 1000,
 356                     p_stats->i_demux_read_packets, p_stats->i_demux_read_bytes,
 357                     p_stats->f_demux_bitrate * 1000,
 358                     p_stats->i_displayed_pictures, p_stats->i_lost_pictures,
 359                     p_stats->i_played_abuffers, p_stats->i_lost_abuffers,
 360                     p_stats->f_send_bitrate );
 361     vlc_mutex_unlock( &p_stats->lock );
 362 }
 363
 364 void __stats_ComputeGlobalStats( vlc_object_t *p_obj,
 365                                 global_stats_t *p_stats )
 366 {
 367     vlc_list_t *p_list;
 368     int i_index;
 369     vlc_mutex_lock( &p_stats->lock );
 370
 371     p_list = vlc_list_find( p_obj, VLC_OBJECT_INPUT, FIND_CHILD );
 372     if( p_list )
 373     {
 374         for( i_index = 0; i_index < p_list->i_count ; i_index ++ )
 375         {
 376             float f_in = 0, f_out = 0;
 377             p_obj = (vlc_object_t *)p_list->p_values[i_index].p_object;
 378             stats_GetFloat( p_obj, p_obj->i_object_id, "input_bitrate",
 379                             &f_in );
 380             stats_GetFloat( p_obj, p_obj->i_object_id, "sout_send_bitrate",
 381                             &f_out );
 382             p_stats->f_input_bitrate += f_in;
 383             p_stats->f_output_bitrate += f_out;
 384         }
 385         vlc_list_release( p_list );
 386     }
 387
 388     vlc_mutex_unlock( &p_stats->lock );
 389 }
 390
 391 void stats_ReinitGlobalStats( global_stats_t *p_stats )
 392 {
 393     p_stats->f_input_bitrate = p_stats->f_output_bitrate = 0.0;
 394 }
 395
 396
 397 void __stats_TimerStart( vlc_object_t *p_obj, const char *psz_name )
 398 {
 399     counter_t *p_counter = stats_CounterGet( p_obj,
 400                                              p_obj->p_vlc->i_object_id,
 401                                              psz_name );
 402     if( !p_counter )
 403     {
 404         counter_sample_t *p_sample;
 405         stats_Create( p_obj->p_vlc, psz_name, VLC_VAR_TIME, STATS_TIMER );
 406         p_counter = stats_CounterGet( p_obj,  p_obj->p_vlc->i_object_id,
 407                                       psz_name );
 408         if( !p_counter ) return;
 409         /* 1st sample : if started: start_date, else last_time, b_started */
 410         p_sample = (counter_sample_t *)malloc( sizeof( counter_sample_t ) );
 411         INSERT_ELEM( p_counter->pp_samples, p_counter->i_samples,
 412                      p_counter->i_samples, p_sample );
 413         p_sample->date = 0; p_sample->value.b_bool = 0;
 414         /* 2nd sample : global_time, i_samples */
 415         p_sample = (counter_sample_t *)malloc( sizeof( counter_sample_t ) );
 416         INSERT_ELEM( p_counter->pp_samples, p_counter->i_samples,
 417                      p_counter->i_samples, p_sample );
 418         p_sample->date = 0; p_sample->value.i_int = 0;
 419     }
 420     if( p_counter->pp_samples[0]->value.b_bool == VLC_TRUE )
 421     {
 422         msg_Warn( p_obj, "timer %s was already started !", psz_name );
 423         return;
 424     }
 425     p_counter->pp_samples[0]->value.b_bool = VLC_TRUE;
 426     p_counter->pp_samples[0]->date = mdate();
 427 }
 428
 429 void __stats_TimerStop( vlc_object_t *p_obj, const char *psz_name )
 430 {
 431     counter_t *p_counter = stats_CounterGet( p_obj,
 432                                               p_obj->p_vlc->i_object_id,
 433                                              psz_name );
 434     if( !p_counter || p_counter->i_samples != 2 )
 435     {
 436         msg_Err( p_obj, "timer %s does not exist", psz_name );
 437         return;
 438     }
 439     p_counter->pp_samples[0]->value.b_bool = VLC_FALSE;
 440     p_counter->pp_samples[1]->value.i_int += 1;
 441     p_counter->pp_samples[0]->date = mdate() - p_counter->pp_samples[0]->date;
 442     p_counter->pp_samples[1]->date += p_counter->pp_samples[0]->date;
 443 }
 444
 445 void __stats_TimerDump( vlc_object_t *p_obj, const char *psz_name )
 446 {
 447     mtime_t last, total;
 448     int i_total;
 449     counter_t *p_counter = stats_CounterGet( p_obj,
 450                                              p_obj->p_vlc->i_object_id,
 451                                              psz_name );
 452     if( !p_counter || p_counter->i_samples != 2 )
 453     {
 454         msg_Err( p_obj, "timer %s does not exist", psz_name );
 455         return;
 456     }
 457     i_total = p_counter->pp_samples[1]->value.i_int;
 458     total = p_counter->pp_samples[1]->date;
 459     if( p_counter->pp_samples[0]->value.b_bool == VLC_TRUE )
 460     {
 461         last = mdate() - p_counter->pp_samples[0]->date;
 462         i_total += 1;
 463         total += last;
 464     }
 465     else
 466     {
 467         last = p_counter->pp_samples[0]->date;
 468     }
 469     msg_Dbg( p_obj, "TIMER %s : %.3f ms - Total %.3f ms / %i intvls (Avg %.3f ms)",
 470              psz_name, (float)last/1000, (float)total/1000, i_total,
 471              (float)(total)/(1000*(float)i_total ) );
 472 }
 473
 474 void __stats_TimersDumpAll( vlc_object_t *p_obj )
 475 {
 476
 477 }
 478
 479
 480 /********************************************************************
 481  * Following functions are local
 482  ********************************************************************/
 483
 484 /**
 485  * Update a statistics counter, according to its type
 486  * If needed, perform a bit of computation (derivative, mostly)
 487  * This function must be entered with stats handler lock
 488  * \param p_handler stats handler singleton
 489  * \param p_counter the counter to update
 490  * \param val the "new" value
 491  * \return an error code
 492  */
 493 static int stats_CounterUpdate( stats_handler_t *p_handler,
 494                                 counter_t *p_counter,
 495                                 vlc_value_t val )
 496 {
 497     switch( p_counter->i_compute_type )
 498     {
 499     case STATS_LAST:
 500     case STATS_MIN:
 501     case STATS_MAX:
 502         if( p_counter->i_samples > 1)
 503         {
 504             msg_Err( p_handler, "LAST counter has several samples !" );
 505             return VLC_EGENERIC;
 506         }
 507         if( p_counter->i_type != VLC_VAR_FLOAT &&
 508             p_counter->i_type != VLC_VAR_INTEGER &&
 509             p_counter->i_compute_type != STATS_LAST )
 510         {
 511             msg_Err( p_handler, "Unable to compute MIN or MAX for this type");
 512             return VLC_EGENERIC;
 513         }
 514
 515         if( p_counter->i_samples == 0 )
 516         {
 517             counter_sample_t *p_new = (counter_sample_t*)malloc(
 518                                                sizeof( counter_sample_t ) );
 519             p_new->value.psz_string = NULL;
 520
 521             INSERT_ELEM( p_counter->pp_samples, p_counter->i_samples,
 522                          p_counter->i_samples, p_new );
 523         }
 524         if( p_counter->i_samples == 1 )
 525         {
 526             /* Update if : LAST or (MAX and bigger) or (MIN and bigger) */
 527             if( p_counter->i_compute_type == STATS_LAST ||
 528                 ( p_counter->i_compute_type == STATS_MAX &&
 529                    ( ( p_counter->i_type == VLC_VAR_INTEGER &&
 530                        p_counter->pp_samples[0]->value.i_int > val.i_int ) ||
 531                      ( p_counter->i_type == VLC_VAR_FLOAT &&
 532                        p_counter->pp_samples[0]->value.f_float > val.f_float )
 533                    ) ) ||
 534                 ( p_counter->i_compute_type == STATS_MIN &&
 535                    ( ( p_counter->i_type == VLC_VAR_INTEGER &&
 536                        p_counter->pp_samples[0]->value.i_int < val.i_int ) ||
 537                      ( p_counter->i_type == VLC_VAR_FLOAT &&
 538                        p_counter->pp_samples[0]->value.f_float < val.f_float )
 539                    ) ) )
 540             {
 541                 if( p_counter->i_type == VLC_VAR_STRING &&
 542                     p_counter->pp_samples[0]->value.psz_string )
 543                 {
 544                     free( p_counter->pp_samples[0]->value.psz_string );
 545                 }
 546                 p_counter->pp_samples[0]->value = val;
 547             }
 548         }
 549         break;
 550     case STATS_DERIVATIVE:
 551     {
 552         counter_sample_t *p_new, *p_old;
 553         if( mdate() - p_counter->last_update < p_counter->update_interval )
 554         {
 555             return VLC_EGENERIC;
 556         }
 557         p_counter->last_update = mdate();
 558         if( p_counter->i_type != VLC_VAR_FLOAT &&
 559             p_counter->i_type != VLC_VAR_INTEGER )
 560         {
 561             msg_Err( p_handler, "Unable to compute DERIVATIVE for this type");
 562             return VLC_EGENERIC;
 563         }
 564         /* Insert the new one at the beginning */
 565         p_new = (counter_sample_t*)malloc( sizeof( counter_sample_t ) );
 566         p_new->value = val;
 567         p_new->date = p_counter->last_update;
 568         INSERT_ELEM( p_counter->pp_samples, p_counter->i_samples,
 569                      0, p_new );
 570
 571         if( p_counter->i_samples == 3 )
 572         {
 573             p_old = p_counter->pp_samples[2];
 574             REMOVE_ELEM( p_counter->pp_samples, p_counter->i_samples, 2 );
 575             free( p_old );
 576         }
 577         break;
 578     }
 579     case STATS_COUNTER:
 580         if( p_counter->i_samples > 1)
 581         {
 582             msg_Err( p_handler, "LAST counter has several samples !" );
 583             return VLC_EGENERIC;
 584         }
 585         if( p_counter->i_samples == 0 )
 586         {
 587             counter_sample_t *p_new = (counter_sample_t*)malloc(
 588                                                sizeof( counter_sample_t ) );
 589             p_new->value.psz_string = NULL;
 590
 591             INSERT_ELEM( p_counter->pp_samples, p_counter->i_samples,
 592                          p_counter->i_samples, p_new );
 593         }
 594         if( p_counter->i_samples == 1 )
 595         {
 596             switch( p_counter->i_type )
 597             {
 598             case VLC_VAR_INTEGER:
 599             case VLC_VAR_FLOAT:
 600                 p_counter->pp_samples[0]->value.i_int += val.i_int;
 601                 break;
 602             default:
 603                 msg_Err( p_handler, "Trying to increment invalid variable %s",
 604                          p_counter->psz_name );
 605                 return VLC_EGENERIC;
 606             }
 607         }
 608         break;
 609     }
 610     return VLC_SUCCESS;
 611 }
 612
 613 static counter_t *GetCounter( stats_handler_t *p_handler, int i_object_id,
 614                               const char *psz_name )
 615 {
 616     int i;
 617    for( i = 0; i< p_handler->i_counters; i++ )
 618     {
 619         counter_t *p_counter = p_handler->pp_counters[i];
 620         if( p_counter->i_source_object == i_object_id &&
 621             !strcmp( p_counter->psz_name, psz_name ) )
 622         {
 623             return p_counter;
 624         }
 625     }
 626     return NULL;
 627 }
 628
 629
 630 static stats_handler_t *stats_HandlerGet( vlc_object_t *p_this )
 631 {
 632     stats_handler_t *p_handler = (stats_handler_t*)
 633                           vlc_object_find( p_this->p_vlc, VLC_OBJECT_STATS,
 634                                            FIND_ANYWHERE );
 635     if( !p_handler )
 636     {
 637         p_handler = stats_HandlerCreate( p_this );
 638         if( !p_handler )
 639         {
 640             return NULL;
 641         }
 642         vlc_object_yield( p_handler );
 643     }
 644     return p_handler;
 645 }
 646
 647 /**
 648  * Initialize statistics handler
 649  *
 650  * This function initializes the global statistics handler singleton,
 651  * \param p_this the parent VLC object
 652  */
 653 static stats_handler_t* stats_HandlerCreate( vlc_object_t *p_this )
 654 {
 655     stats_handler_t *p_handler;
 656
 657     msg_Dbg( p_this, "creating statistics handler" );
 658
 659     p_handler = (stats_handler_t*) vlc_object_create( p_this,
 660                                                       VLC_OBJECT_STATS );
 661
 662     if( !p_handler )
 663     {
 664         msg_Err( p_this, "out of memory" );
 665         return NULL;
 666     }
 667     p_handler->i_counters = 0;
 668     p_handler->pp_counters = NULL;
 669
 670     /// \bug is it p_vlc or p_libvlc ?
 671     vlc_object_attach( p_handler, p_this->p_vlc );
 672
 673     return p_handler;
 674 }