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

   1 /*****************************************************************************
   2  * block.c: Data blocks management functions
   3  *****************************************************************************
   4  * Copyright (C) 2003 VideoLAN
   5  * $Id: block.c,v 1.2 2003/09/02 20:19:26 gbazin Exp $
   6  *
   7  * Authors: Laurent Aimar <fenrir@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., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  22  *****************************************************************************/
  23
  24 /*****************************************************************************
  25  * Preamble
  26  *****************************************************************************/
  27 #include <stdlib.h>
  28 #include <stdarg.h>
  29
  30 #include <vlc/vlc.h>
  31 #include "vlc_block.h"
  32
  33 /* private */
  34 struct block_sys_t
  35 {
  36     vlc_mutex_t lock;
  37
  38     uint8_t     *p_allocated_buffer;
  39     int         i_allocated_buffer;
  40
  41     vlc_bool_t  b_modify;       /* has it been put in modified state */
  42     int         i_duplicated;   /* how many times has the content been
  43                                  * duplicated */
  44
  45 };
  46
  47 static void BlockRelease( block_t *p_block )
  48 {
  49     vlc_mutex_lock( &p_block->p_sys->lock );
  50
  51     p_block->p_sys->i_duplicated--;
  52     if( p_block->p_sys->i_duplicated < 0 )
  53     {
  54         vlc_mutex_unlock( &p_block->p_sys->lock );
  55         free( p_block->p_sys->p_allocated_buffer );
  56         free( p_block->p_sys );
  57         free( p_block );
  58
  59         return;
  60     }
  61
  62     vlc_mutex_unlock( &p_block->p_sys->lock );
  63     free( p_block );
  64 }
  65
  66 static block_t *__BlockDupContent( block_t *p_block )
  67 {
  68     block_t *p_dup;
  69
  70     p_dup = block_New( p_block->p_manager, p_block->i_buffer );
  71     memcpy( p_dup->p_buffer, p_block->p_buffer, p_block->i_buffer );
  72     p_dup->b_frame_display = p_block->b_frame_display;
  73     p_dup->b_frame_start   = p_block->b_frame_start;
  74     p_dup->i_pts           = p_block->i_pts;
  75     p_dup->i_dts           = p_block->i_dts;
  76
  77     return p_dup;
  78 }
  79
  80 static block_t *BlockModify( block_t *p_block, vlc_bool_t b_will_modify )
  81 {
  82     block_t *p_mod = p_block;   /* by default */
  83
  84     vlc_mutex_lock( &p_block->p_sys->lock );
  85
  86     if( p_block->p_sys->b_modify == b_will_modify )
  87     {
  88         vlc_mutex_unlock( &p_block->p_sys->lock );
  89         return p_block;
  90     }
  91
  92     if( p_block->p_sys->i_duplicated == 0 )
  93     {
  94         p_block->p_sys->b_modify = b_will_modify;
  95         vlc_mutex_unlock( &p_block->p_sys->lock );
  96         return p_block;
  97     }
  98
  99     /* FIXME we could avoid that
 100      * we just need to create a new p_sys with new mem FIXME */
 101     p_mod = __BlockDupContent( p_block );
 102     vlc_mutex_unlock( &p_block->p_sys->lock );
 103
 104     BlockRelease( p_block );
 105
 106     return p_mod;
 107 }
 108
 109 static block_t *BlockDuplicate( block_t *p_block )
 110 {
 111     block_t *p_dup;
 112
 113     vlc_mutex_lock( &p_block->p_sys->lock );
 114     if( !p_block->p_sys->b_modify )
 115     {
 116         p_block->p_sys->i_duplicated++;
 117         vlc_mutex_unlock( &p_block->p_sys->lock );
 118         p_dup = block_NewEmpty();
 119         memcpy( p_dup, p_block, sizeof( block_t ) );
 120         p_dup->p_next = NULL;
 121         return p_dup;
 122     }
 123     p_dup = __BlockDupContent( p_block );
 124     vlc_mutex_unlock( &p_block->p_sys->lock );
 125
 126     return p_dup;
 127 }
 128
 129 static block_t *BlockRealloc( block_t *p_block, int i_prebody, int i_body )
 130 {
 131
 132     vlc_mutex_lock( &p_block->p_sys->lock );
 133     if( i_prebody < 0 || p_block->p_buffer - i_prebody >
 134         p_block->p_sys->p_allocated_buffer )
 135     {
 136         p_block->p_buffer -= i_prebody;
 137         p_block->i_buffer += i_prebody;
 138         i_prebody = 0;
 139     }
 140     if( i_body < 0 ||
 141         p_block->p_buffer + i_body < p_block->p_sys->p_allocated_buffer +
 142         p_block->p_sys->i_allocated_buffer )
 143     {
 144         p_block->i_buffer = i_body;
 145         i_body = 0;
 146     }
 147     vlc_mutex_unlock( &p_block->p_sys->lock );
 148
 149     if( i_prebody > 0 )
 150     {
 151         block_t *p_rea = block_New( p_block->p_manager, i_prebody + i_body );
 152
 153         memcpy( &p_rea->p_buffer[i_prebody], p_block->p_buffer,
 154                 p_block->i_buffer );
 155
 156         return p_rea;
 157     }
 158
 159     if( i_body > 0 )
 160     {
 161         int i_start;
 162         block_t *p_rea = BlockModify( p_block, VLC_TRUE );
 163
 164         i_start = p_rea->p_buffer - p_rea->p_sys->p_allocated_buffer;
 165
 166         p_rea->p_sys->i_allocated_buffer += i_body - p_rea->i_buffer;
 167         p_rea->p_sys->p_allocated_buffer =
 168             realloc( p_rea->p_sys->p_allocated_buffer,
 169                      p_rea->p_sys->i_allocated_buffer );
 170
 171         p_rea->p_buffer = &p_rea->p_sys->p_allocated_buffer[i_start];
 172         p_rea->i_buffer = i_body;
 173
 174         return p_rea;
 175     }
 176
 177     return p_block;
 178 }
 179
 180 /*****************************************************************************
 181  * Standard block management
 182  *
 183  *****************************************************************************/
 184 /* to be used by other block managment */
 185 block_t *block_NewEmpty( void )
 186 {
 187     block_t *p_block;
 188
 189     p_block = malloc( sizeof( block_t ) );
 190     p_block->p_next         = NULL;
 191     p_block->b_frame_display= VLC_TRUE;
 192     p_block->b_frame_start  = VLC_FALSE;
 193     p_block->i_pts          = 0;
 194     p_block->i_dts          = 0;
 195
 196     p_block->i_buffer       = 0;
 197     p_block->p_buffer       = NULL;
 198
 199     p_block->pf_release     = NULL;
 200     p_block->pf_duplicate   = NULL;
 201     p_block->pf_modify      = NULL;
 202     p_block->pf_realloc     = NULL;
 203
 204     p_block->p_sys = NULL;
 205     return p_block;
 206 }
 207
 208 block_t *__block_New( vlc_object_t *p_obj, int i_size )
 209 {
 210     block_t     *p_block;
 211     block_sys_t *p_sys;
 212
 213     p_block = block_NewEmpty();
 214
 215     p_block->i_buffer       = i_size;
 216     if( i_size > 0 )
 217     {
 218         p_block->p_buffer   = malloc( i_size );
 219     }
 220
 221     p_block->pf_release     = BlockRelease;
 222     p_block->pf_duplicate   = BlockDuplicate;
 223     p_block->pf_modify      = BlockModify;
 224     p_block->pf_realloc     = BlockRealloc;
 225
 226     /* that should be ok (no comunication between multiple p_vlc) */
 227     p_block->p_manager      = VLC_OBJECT( p_obj->p_vlc );
 228
 229     p_block->p_sys = p_sys = malloc( sizeof( block_sys_t ) );
 230     vlc_mutex_init( p_obj, &p_sys->lock );
 231     p_sys->p_allocated_buffer = p_block->p_buffer;
 232     p_sys->i_allocated_buffer = p_block->i_buffer;
 233     p_sys->i_duplicated = 0;
 234     p_sys->b_modify = VLC_TRUE;
 235
 236     return p_block;
 237 }
 238
 239 void block_ChainAppend( block_t **pp_list, block_t *p_block )
 240 {
 241
 242     if( *pp_list == NULL )
 243     {
 244         *pp_list = p_block;
 245     }
 246     else
 247     {
 248         block_t *p = *pp_list;
 249
 250         while( p->p_next )
 251         {
 252             p = p->p_next;
 253         }
 254         p->p_next = p_block;
 255     }
 256 }
 257
 258 void block_ChainRelease( block_t *p_block )
 259 {
 260     while( p_block )
 261     {
 262         block_t *p_next;
 263         p_next = p_block->p_next;
 264         p_block->pf_release( p_block );
 265         p_block = p_next;
 266     }
 267 }
 268
 269 int block_ChainExtract( block_t *p_list, void *p_data, int i_max )
 270 {
 271     block_t *b;
 272     int     i_total = 0;
 273     uint8_t *p = p_data;
 274
 275     for( b = p_list; b != NULL; b = b->p_next )
 276     {
 277         int i_copy;
 278
 279         i_copy = __MIN( i_max, b->i_buffer );
 280         if( i_copy > 0 )
 281         {
 282             memcpy( p, b->p_buffer, i_copy );
 283             i_max   -= i_copy;
 284             i_total += i_copy;
 285             p       += i_copy;
 286
 287             if( i_max == 0 )
 288             {
 289                 return i_total;
 290             }
 291         }
 292     }
 293     return i_total;
 294 }
 295
 296 block_t *block_ChainGather( block_t *p_list )
 297 {
 298     int     i_total = 0;
 299     block_t *b, *g;
 300
 301     if( p_list->p_next == NULL )
 302     {
 303         /* only one, so no need */
 304         return p_list;
 305     }
 306
 307     for( b = p_list; b != NULL; b = b->p_next )
 308     {
 309         i_total += b->i_buffer;
 310     }
 311
 312     g = block_New( p_list->p_manager, i_total );
 313     block_ChainExtract( p_list, g->p_buffer, g->i_buffer );
 314
 315     g->b_frame_display = p_list->b_frame_display;
 316     g->b_frame_start   = p_list->b_frame_start;
 317     g->i_pts           = p_list->i_pts;
 318     g->i_dts           = p_list->i_dts;
 319
 320     /* free p_list */
 321     block_ChainRelease( p_list );
 322     return g;
 323 }
 324
 325
 326 /*****************************************************************************
 327  * block_fifo_t managment
 328  *****************************************************************************/
 329 block_fifo_t *__block_FifoNew( vlc_object_t *p_obj )
 330 {
 331     block_fifo_t *p_fifo;
 332
 333     p_fifo = malloc( sizeof( vlc_object_t ) );
 334     vlc_mutex_init( p_obj, &p_fifo->lock );
 335     vlc_cond_init( p_obj, &p_fifo->wait );
 336     p_fifo->i_depth = 0;
 337     p_fifo->p_first = NULL;
 338     p_fifo->pp_last = &p_fifo->p_first;
 339
 340     return p_fifo;
 341 }
 342
 343 void block_FifoRelease( block_fifo_t *p_fifo )
 344 {
 345     block_FifoEmpty( p_fifo );
 346     vlc_cond_destroy( &p_fifo->wait );
 347     vlc_mutex_destroy( &p_fifo->lock );
 348     free( p_fifo );
 349 }
 350
 351 void block_FifoEmpty( block_fifo_t *p_fifo )
 352 {
 353     block_t *b;
 354
 355     vlc_mutex_lock( &p_fifo->lock );
 356     for( b = p_fifo->p_first; b != NULL; )
 357     {
 358         block_t *p_next;
 359
 360         p_next = b->p_next;
 361         block_Release( b );
 362         b = p_next;
 363     }
 364
 365     p_fifo->i_depth = 0;
 366     p_fifo->p_first = NULL;
 367     p_fifo->pp_last = &p_fifo->p_first;
 368     vlc_mutex_unlock( &p_fifo->lock );
 369 }
 370
 371 int block_FifoPut( block_fifo_t *p_fifo, block_t *p_block )
 372 {
 373     int i_size = 0;
 374     vlc_mutex_lock( &p_fifo->lock );
 375
 376     do
 377     {
 378         i_size += p_block->i_buffer;
 379
 380         *p_fifo->pp_last = p_block;
 381         p_fifo->pp_last = &p_block->p_next;
 382         p_fifo->i_depth++;
 383
 384         p_block = p_block->p_next;
 385
 386     } while( p_block );
 387
 388     /* warn there is data in this fifo */
 389     vlc_cond_signal( &p_fifo->wait );
 390     vlc_mutex_unlock( &p_fifo->lock );
 391
 392     return i_size;
 393 }
 394
 395 block_t *block_FifoGet( block_fifo_t *p_fifo )
 396 {
 397     block_t *b;
 398
 399     vlc_mutex_lock( &p_fifo->lock );
 400
 401     if( p_fifo->p_first == NULL )
 402     {
 403         vlc_cond_wait( &p_fifo->wait, &p_fifo->lock );
 404     }
 405
 406     b = p_fifo->p_first;
 407
 408     p_fifo->p_first = b->p_next;
 409     p_fifo->i_depth--;
 410
 411     if( p_fifo->p_first == NULL )
 412     {
 413         p_fifo->pp_last = &p_fifo->p_first;
 414     }
 415
 416     vlc_mutex_unlock( &p_fifo->lock );
 417
 418     b->p_next = NULL;
 419     return( b );
 420 }
 421
 422 block_t *block_FifoShow( block_fifo_t *p_fifo )
 423 {
 424     block_t *b;
 425
 426     vlc_mutex_lock( &p_fifo->lock );
 427
 428     if( p_fifo->p_first == NULL )
 429     {
 430         vlc_cond_wait( &p_fifo->wait, &p_fifo->lock );
 431     }
 432
 433     b = p_fifo->p_first;
 434
 435     vlc_mutex_unlock( &p_fifo->lock );
 436
 437     return( b );
 438
 439 }
 440
 441 block_t *block_FifoGetFrame( block_fifo_t *p_fifo )
 442 {
 443     block_t *b = NULL;
 444
 445     for( ;; )
 446     {
 447         block_t *p_next;
 448         block_ChainAppend( &b, block_FifoGet( p_fifo ) );
 449         p_next = block_FifoShow( p_fifo );
 450         if( p_next == NULL || p_next->b_frame_start )
 451         {
 452             break;
 453         }
 454     }
 455
 456     return b;
 457 }