git.sesse.net Git - vlc/blob - src/input/stream.c

   1 /*****************************************************************************
   2  * stream.c
   3  *****************************************************************************
   4  * Copyright (C) 1999-2001 VideoLAN
   5  * $Id: stream.c,v 1.5 2003/09/08 00:36:26 fenrir Exp $
   6  *
   7  * Authors: Laurent Aimar <fenrir@via.ecp.fr>
   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 #include <stdlib.h>
  25 #include <vlc/vlc.h>
  26 #include <vlc/input.h>
  27
  28 #include "ninput.h"
  29
  30 /****************************************************************************
  31  * stream_* :
  32  * XXX for now it's just a wrapper
  33  *
  34  ****************************************************************************/
  35
  36 /**
  37  * Handle to a stream.
  38  */
  39 struct stream_t
  40 {
  41     VLC_COMMON_MEMBERS
  42
  43     /** pointer to the input thread */
  44     input_thread_t *p_input;
  45
  46 };
  47
  48 /**
  49  * Create a "stream_t *" from an "input_thread_t *".
  50  */
  51 stream_t    *stream_OpenInput( input_thread_t *p_input )
  52 {
  53     stream_t *s;
  54
  55     s = vlc_object_create( p_input, sizeof( stream_t ) );
  56     if( s )
  57     {
  58         s->p_input = p_input;
  59     }
  60
  61     return s;
  62 }
  63
  64 /**
  65  * Destroy a previously created "stream_t *" instance.
  66  */
  67 void        stream_Release( stream_t *s )
  68 {
  69     vlc_object_destroy( s );
  70 }
  71
  72 /**
  73  * Similar to #stream_Control(), but takes a va_list and not variable arguments.
  74  */
  75 int         stream_vaControl( stream_t *s, int i_query, va_list args )
  76 {
  77     vlc_bool_t *p_b;
  78     int64_t    *p_i64, i64;
  79
  80     switch( i_query )
  81     {
  82         case STREAM_GET_SIZE:
  83             p_i64 = (int64_t*) va_arg( args, int64_t * );
  84
  85             vlc_mutex_lock( &s->p_input->stream.stream_lock );
  86             *p_i64 = s->p_input->stream.p_selected_area->i_size;
  87             vlc_mutex_unlock( &s->p_input->stream.stream_lock );
  88             return VLC_SUCCESS;
  89
  90         case STREAM_CAN_SEEK:
  91             p_b = (vlc_bool_t*) va_arg( args, vlc_bool_t * );
  92
  93             vlc_mutex_lock( &s->p_input->stream.stream_lock );
  94             *p_b = s->p_input->stream.b_seekable;
  95             vlc_mutex_unlock( &s->p_input->stream.stream_lock );
  96             return VLC_SUCCESS;
  97
  98         case STREAM_CAN_FASTSEEK:
  99             p_b = (vlc_bool_t*) va_arg( args, vlc_bool_t * );
 100
 101             vlc_mutex_lock( &s->p_input->stream.stream_lock );
 102             *p_b = s->p_input->stream.b_seekable && s->p_input->stream.i_method == INPUT_METHOD_FILE;
 103             vlc_mutex_unlock( &s->p_input->stream.stream_lock );
 104             return VLC_SUCCESS;
 105
 106         case STREAM_GET_POSITION:
 107             p_i64 = (int64_t*) va_arg( args, int64_t * );
 108
 109             vlc_mutex_lock( &s->p_input->stream.stream_lock );
 110             *p_i64 = s->p_input->stream.p_selected_area->i_tell;
 111             vlc_mutex_unlock( &s->p_input->stream.stream_lock );
 112             return VLC_SUCCESS;
 113
 114         case STREAM_SET_POSITION:
 115             i64 = (int64_t) va_arg( args, int64_t );
 116
 117             vlc_mutex_lock( &s->p_input->stream.stream_lock );
 118             if( i64 < 0 ||
 119                 ( s->p_input->stream.p_selected_area->i_size > 0 &&
 120                   s->p_input->stream.p_selected_area->i_size < i64 ) )
 121             {
 122                 vlc_mutex_unlock( &s->p_input->stream.stream_lock );
 123                 msg_Warn( s, "seek out of bound" );
 124                 return VLC_EGENERIC;
 125             }
 126             vlc_mutex_unlock( &s->p_input->stream.stream_lock );
 127
 128             if( i64 == s->p_input->stream.p_selected_area->i_tell )
 129             {
 130                 return VLC_SUCCESS;
 131             }
 132
 133             if( s->p_input->stream.b_seekable &&
 134                 ( s->p_input->stream.i_method == INPUT_METHOD_FILE ||
 135                   i64 - s->p_input->stream.p_selected_area->i_tell < 0 ||
 136                   i64 - s->p_input->stream.p_selected_area->i_tell > 4096 ) )
 137             {
 138                 input_AccessReinit( s->p_input );
 139                 s->p_input->pf_seek( s->p_input, i64 );
 140                 return VLC_SUCCESS;
 141             }
 142
 143             if( i64 - s->p_input->stream.p_selected_area->i_tell > 0 )
 144             {
 145                 data_packet_t   *p_data;
 146                 int             i_skip = i64 - s->p_input->stream.p_selected_area->i_tell;
 147
 148                 if( i_skip > 1000 )
 149                 {
 150                     msg_Warn( s, "will skip %d bytes, slow", i_skip );
 151                 }
 152
 153                 while (i_skip > 0 )
 154                 {
 155                     int i_read;
 156
 157                     i_read = input_SplitBuffer( s->p_input, &p_data,
 158                                                 __MIN( (int)s->p_input->i_bufsize, i_skip ) );
 159                     if( i_read < 0 )
 160                     {
 161                         return VLC_EGENERIC;
 162                     }
 163                     i_skip -= i_read;
 164
 165                     input_DeletePacket( s->p_input->p_method_data, p_data );
 166                     if( i_read == 0 && i_skip > 0 )
 167                     {
 168                         return VLC_EGENERIC;
 169                     }
 170                 }
 171             }
 172
 173             return VLC_SUCCESS;
 174
 175         default:
 176             msg_Err( s, "invalid stream_vaControl query=0x%x", i_query );
 177             return VLC_EGENERIC;
 178     }
 179 }
 180
 181 /**
 182  * Use to control the "stream_t *". Look at #stream_query_e for
 183  * possible "i_query" value and format arguments.  Return VLC_SUCCESS
 184  * if ... succeed ;) and VLC_EGENERIC if failed or unimplemented
 185  */
 186 int         stream_Control( stream_t *s, int i_query, ... )
 187 {
 188     va_list args;
 189     int     i_result;
 190
 191     va_start( args, i_query );
 192     i_result = stream_vaControl( s, i_query, args );
 193     va_end( args );
 194
 195     return i_result;
 196 }
 197
 198 /**
 199  * Try to read "i_read" bytes into a buffer pointed by "p_read".  If
 200  * "p_read" is NULL then data are skipped instead of read.  The return
 201  * value is the real numbers of bytes read/skip. If this value is less
 202  * than i_read that means that it's the end of the stream.
 203  */
 204 int         stream_Read( stream_t *s, void *p_data, int i_data )
 205 {
 206     uint8_t       *p = (uint8_t*)p_data;
 207     data_packet_t *p_packet;
 208
 209     int i_read = 0;
 210
 211     if( p_data == NULL && i_data > 0 )
 212     {
 213         int64_t i_pos;
 214
 215         stream_Control( s, STREAM_GET_POSITION, &i_pos );
 216
 217         i_pos += i_data;
 218         if( stream_Control( s, STREAM_SET_POSITION, i_pos ) )
 219         {
 220             return 0;
 221         }
 222         return i_data;
 223     }
 224
 225     while( i_data > 0 && !s->p_input->b_die )
 226     {
 227         int i_count;
 228
 229         i_count = input_SplitBuffer( s->p_input, &p_packet,
 230                                      __MIN( i_data, (int)s->p_input->i_bufsize ) );
 231         if( i_count <= 0 )
 232         {
 233             return i_read;
 234         }
 235
 236         if( p )
 237         {
 238             memcpy( p, p_packet->p_payload_start, i_count );
 239             p += i_count;
 240         }
 241
 242         input_DeletePacket( s->p_input->p_method_data, p_packet );
 243
 244         i_data -= i_count;
 245         i_read += i_count;
 246     }
 247
 248     return i_read;
 249 }
 250
 251 /**
 252  * Store in pp_peek a pointer to the next "i_peek" bytes in the stream
 253  * The return value is the real numbers of valid bytes, if it's less
 254  * or equal to 0, *pp_peek is invalid.  XXX: it's a pointer to
 255  * internal buffer and it will be invalid as soons as other stream_*
 256  * functions are called.  be 0 (then *pp_peek isn't valid).  XXX: due
 257  * to input limitation, it could be less than i_peek without meaning
 258  * the end of the stream (but only when you have i_peek >=
 259  * p_input->i_bufsize)
 260  */
 261 int         stream_Peek( stream_t *s, uint8_t **pp_peek, int i_data )
 262 {
 263     return input_Peek( s->p_input, pp_peek, i_data );
 264 }
 265
 266 /**
 267  * Read "i_size" bytes and store them in a pes_packet_t.  Only fields
 268  * p_first, p_last, i_nb_data, and i_pes_size are set.  (Of course,
 269  * you need to fill i_dts, i_pts, ... ) If only less than "i_size"
 270  * bytes are available NULL is returned.
 271  */
 272 pes_packet_t    *stream_PesPacket( stream_t *s, int i_data )
 273 {
 274     pes_packet_t  *p_pes;
 275     data_packet_t *p_packet;
 276
 277
 278     if( !(p_pes = input_NewPES( s->p_input->p_method_data ) ) )
 279     {
 280         return NULL;
 281     }
 282
 283     if( i_data <= 0 )
 284     {
 285         p_pes->p_first =
 286             p_pes->p_last  =
 287                 input_NewPacket( s->p_input->p_method_data, 0 );
 288         p_pes->i_nb_data = 1;
 289         return p_pes;
 290     }
 291
 292     while( i_data > 0 )
 293     {
 294         int i_read;
 295
 296         i_read = input_SplitBuffer( s->p_input, &p_packet,
 297                                     __MIN( i_data, (int)s->p_input->i_bufsize ) );
 298         if( i_read <= 0 )
 299         {
 300             /* should occur only with EOF and max allocation reached
 301              * it safer to  return an error */
 302             /* free pes */
 303             input_DeletePES( s->p_input->p_method_data, p_pes );
 304             return NULL;
 305         }
 306
 307         if( p_pes->p_first == NULL )
 308         {
 309             p_pes->p_first = p_packet;
 310         }
 311         else
 312         {
 313             p_pes->p_last->p_next = p_packet;
 314         }
 315         p_pes->p_last = p_packet;
 316         p_pes->i_nb_data++;
 317         p_pes->i_pes_size += i_read;
 318         i_data            -= i_read;
 319     }
 320
 321     return p_pes;
 322 }
 323
 324 /**
 325  * Read i_size into a data_packet_t. If b_force is not set, fewer bytes can
 326  * be returned. You should always set b_force, unless you know what you are
 327  * doing.
 328  */
 329 data_packet_t *stream_DataPacket( stream_t *s, int i_size, vlc_bool_t b_force )
 330 {
 331     data_packet_t *p_pk;
 332     int           i_read;
 333
 334     if( i_size <= 0 )
 335     {
 336         p_pk = input_NewPacket( s->p_input->p_method_data, 0 );
 337         if( p_pk )
 338         {
 339             p_pk->p_payload_end = p_pk->p_payload_start;
 340         }
 341         return p_pk;
 342     }
 343
 344     i_read = input_SplitBuffer( s->p_input, &p_pk, i_size );
 345     if( i_read <= 0 )
 346     {
 347         return NULL;
 348     }
 349
 350     /* Should be really rare, near 0 */
 351     if( i_read < i_size && b_force )
 352     {
 353         data_packet_t *p_old = p_pk;
 354         int           i_missing = i_size - i_read;
 355
 356         p_pk = input_NewPacket( s->p_input->p_method_data, i_size );
 357         if( p_pk == NULL )
 358         {
 359             input_DeletePacket( s->p_input->p_method_data, p_old );
 360             return NULL;
 361         }
 362         p_pk->p_payload_end = p_pk->p_payload_start + i_size;
 363         memcpy( p_pk->p_payload_start, p_old->p_payload_start, i_read );
 364         input_DeletePacket( s->p_input->p_method_data, p_old );
 365
 366         if( stream_Read( s, &p_pk->p_payload_start[i_read], i_missing ) < i_missing )
 367         {
 368             input_DeletePacket( s->p_input->p_method_data, p_pk );
 369             return NULL;
 370         }
 371     }
 372
 373     return p_pk;
 374 }
 375
 376
 377