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 1.6 2003/10/08 21:01:07 gbazin 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
  74  * arguments.
  75  */
  76 int stream_vaControl( stream_t *s, int i_query, va_list args )
  77 {
  78     vlc_bool_t *p_b;
  79     int64_t    *p_i64, i64;
  80
  81     switch( i_query )
  82     {
  83         case STREAM_GET_SIZE:
  84             p_i64 = (int64_t*) va_arg( args, int64_t * );
  85
  86             vlc_mutex_lock( &s->p_input->stream.stream_lock );
  87             *p_i64 = s->p_input->stream.p_selected_area->i_size;
  88             vlc_mutex_unlock( &s->p_input->stream.stream_lock );
  89             return VLC_SUCCESS;
  90
  91         case STREAM_CAN_SEEK:
  92             p_b = (vlc_bool_t*) va_arg( args, vlc_bool_t * );
  93
  94             vlc_mutex_lock( &s->p_input->stream.stream_lock );
  95             *p_b = s->p_input->stream.b_seekable;
  96             vlc_mutex_unlock( &s->p_input->stream.stream_lock );
  97             return VLC_SUCCESS;
  98
  99         case STREAM_CAN_FASTSEEK:
 100             p_b = (vlc_bool_t*) va_arg( args, vlc_bool_t * );
 101
 102             vlc_mutex_lock( &s->p_input->stream.stream_lock );
 103             *p_b = s->p_input->stream.b_seekable &&
 104                    s->p_input->stream.i_method == INPUT_METHOD_FILE;
 105             vlc_mutex_unlock( &s->p_input->stream.stream_lock );
 106             return VLC_SUCCESS;
 107
 108         case STREAM_GET_POSITION:
 109             p_i64 = (int64_t*) va_arg( args, int64_t * );
 110
 111             vlc_mutex_lock( &s->p_input->stream.stream_lock );
 112             *p_i64 = s->p_input->stream.p_selected_area->i_tell;
 113             vlc_mutex_unlock( &s->p_input->stream.stream_lock );
 114             return VLC_SUCCESS;
 115
 116         case STREAM_SET_POSITION:
 117             i64 = (int64_t) va_arg( args, int64_t );
 118
 119             vlc_mutex_lock( &s->p_input->stream.stream_lock );
 120             if( i64 < 0 ||
 121                 ( s->p_input->stream.p_selected_area->i_size > 0 &&
 122                   s->p_input->stream.p_selected_area->i_size < i64 ) )
 123             {
 124                 vlc_mutex_unlock( &s->p_input->stream.stream_lock );
 125                 msg_Warn( s, "seek out of bound" );
 126                 return VLC_EGENERIC;
 127             }
 128             vlc_mutex_unlock( &s->p_input->stream.stream_lock );
 129
 130             if( i64 == s->p_input->stream.p_selected_area->i_tell )
 131             {
 132                 return VLC_SUCCESS;
 133             }
 134
 135             if( s->p_input->stream.b_seekable &&
 136                 ( s->p_input->stream.i_method == INPUT_METHOD_FILE ||
 137                   i64 - s->p_input->stream.p_selected_area->i_tell < 0 ||
 138                   i64 - s->p_input->stream.p_selected_area->i_tell > 4096 ) )
 139             {
 140                 input_AccessReinit( s->p_input );
 141                 s->p_input->pf_seek( s->p_input, i64 );
 142                 return VLC_SUCCESS;
 143             }
 144
 145             if( i64 - s->p_input->stream.p_selected_area->i_tell > 0 )
 146             {
 147                 data_packet_t *p_data;
 148                 int i_skip = i64 - s->p_input->stream.p_selected_area->i_tell;
 149
 150                 if( i_skip > 1000 )
 151                 {
 152                     msg_Warn( s, "will skip %d bytes, slow", i_skip );
 153                 }
 154
 155                 while (i_skip > 0 )
 156                 {
 157                     int i_read;
 158
 159                     i_read = input_SplitBuffer( s->p_input, &p_data,
 160                                  __MIN( (int)s->p_input->i_bufsize, i_skip ) );
 161                     if( i_read < 0 )
 162                     {
 163                         return VLC_EGENERIC;
 164                     }
 165                     i_skip -= i_read;
 166
 167                     input_DeletePacket( s->p_input->p_method_data, p_data );
 168                     if( i_read == 0 && i_skip > 0 )
 169                     {
 170                         return VLC_EGENERIC;
 171                     }
 172                 }
 173             }
 174
 175             return VLC_SUCCESS;
 176
 177         default:
 178             msg_Err( s, "invalid stream_vaControl query=0x%x", i_query );
 179             return VLC_EGENERIC;
 180     }
 181 }
 182
 183 /**
 184  * Use to control the "stream_t *". Look at #stream_query_e for
 185  * possible "i_query" value and format arguments.  Return VLC_SUCCESS
 186  * if ... succeed ;) and VLC_EGENERIC if failed or unimplemented
 187  */
 188 int stream_Control( stream_t *s, int i_query, ... )
 189 {
 190     va_list args;
 191     int     i_result;
 192
 193     va_start( args, i_query );
 194     i_result = stream_vaControl( s, i_query, args );
 195     va_end( args );
 196
 197     return i_result;
 198 }
 199
 200 /**
 201  * Try to read "i_read" bytes into a buffer pointed by "p_read".  If
 202  * "p_read" is NULL then data are skipped instead of read.  The return
 203  * value is the real numbers of bytes read/skip. If this value is less
 204  * than i_read that means that it's the end of the stream.
 205  */
 206 int stream_Read( stream_t *s, void *p_data, int i_data )
 207 {
 208     uint8_t       *p = (uint8_t*)p_data;
 209     data_packet_t *p_packet;
 210
 211     int i_read = 0;
 212
 213     if( p_data == NULL && i_data > 0 )
 214     {
 215         int64_t i_pos;
 216
 217         stream_Control( s, STREAM_GET_POSITION, &i_pos );
 218
 219         i_pos += i_data;
 220         if( stream_Control( s, STREAM_SET_POSITION, i_pos ) )
 221         {
 222             return 0;
 223         }
 224         return i_data;
 225     }
 226
 227     while( i_data > 0 && !s->p_input->b_die )
 228     {
 229         int i_count;
 230
 231         i_count = input_SplitBuffer( s->p_input, &p_packet,
 232                       __MIN( i_data, (int)s->p_input->i_bufsize ) );
 233         if( i_count <= 0 )
 234         {
 235             return i_read;
 236         }
 237
 238         if( p )
 239         {
 240             memcpy( p, p_packet->p_payload_start, i_count );
 241             p += i_count;
 242         }
 243
 244         input_DeletePacket( s->p_input->p_method_data, p_packet );
 245
 246         i_data -= i_count;
 247         i_read += i_count;
 248     }
 249
 250     return i_read;
 251 }
 252
 253 /**
 254  * Store in pp_peek a pointer to the next "i_peek" bytes in the stream
 255  * The return value is the real numbers of valid bytes, if it's less
 256  * or equal to 0, *pp_peek is invalid.  XXX: it's a pointer to
 257  * internal buffer and it will be invalid as soons as other stream_*
 258  * functions are called.  be 0 (then *pp_peek isn't valid).  XXX: due
 259  * to input limitation, it could be less than i_peek without meaning
 260  * the end of the stream (but only when you have i_peek >=
 261  * p_input->i_bufsize)
 262  */
 263 int stream_Peek( stream_t *s, uint8_t **pp_peek, int i_data )
 264 {
 265     return input_Peek( s->p_input, pp_peek, i_data );
 266 }
 267
 268 /**
 269  * Read "i_size" bytes and store them in a pes_packet_t.  Only fields
 270  * p_first, p_last, i_nb_data, and i_pes_size are set.  (Of course,
 271  * you need to fill i_dts, i_pts, ... ) If only less than "i_size"
 272  * bytes are available NULL is returned.
 273  */
 274 pes_packet_t *stream_PesPacket( stream_t *s, int i_data )
 275 {
 276     pes_packet_t  *p_pes;
 277     data_packet_t *p_packet;
 278
 279
 280     if( !(p_pes = input_NewPES( s->p_input->p_method_data ) ) )
 281     {
 282         return NULL;
 283     }
 284
 285     if( i_data <= 0 )
 286     {
 287         p_pes->p_first =
 288             p_pes->p_last = input_NewPacket( s->p_input->p_method_data, 0 );
 289         p_pes->i_nb_data = 1;
 290         return p_pes;
 291     }
 292
 293     while( i_data > 0 )
 294     {
 295         int i_read;
 296
 297         i_read = input_SplitBuffer( s->p_input, &p_packet,
 298                      __MIN( i_data, (int)s->p_input->i_bufsize ) );
 299         if( i_read <= 0 )
 300         {
 301             /* should occur only with EOF and max allocation reached
 302              * it safer to  return an error */
 303             /* free pes */
 304             input_DeletePES( s->p_input->p_method_data, p_pes );
 305             return NULL;
 306         }
 307
 308         if( p_pes->p_first == NULL )
 309         {
 310             p_pes->p_first = p_packet;
 311         }
 312         else
 313         {
 314             p_pes->p_last->p_next = p_packet;
 315         }
 316         p_pes->p_last = p_packet;
 317         p_pes->i_nb_data++;
 318         p_pes->i_pes_size += i_read;
 319         i_data -= i_read;
 320     }
 321
 322     return p_pes;
 323 }
 324
 325 /**
 326  * Read i_size into a data_packet_t. If b_force is not set, fewer bytes can
 327  * be returned. You should always set b_force, unless you know what you are
 328  * doing.
 329  */
 330 data_packet_t *stream_DataPacket( stream_t *s, int i_size, vlc_bool_t b_force )
 331 {
 332     data_packet_t *p_pk;
 333     int           i_read;
 334
 335     if( i_size <= 0 )
 336     {
 337         p_pk = input_NewPacket( s->p_input->p_method_data, 0 );
 338         if( p_pk )
 339         {
 340             p_pk->p_payload_end = p_pk->p_payload_start;
 341         }
 342         return p_pk;
 343     }
 344
 345     i_read = input_SplitBuffer( s->p_input, &p_pk, i_size );
 346     if( i_read <= 0 )
 347     {
 348         return NULL;
 349     }
 350
 351     /* Should be really rare, near 0 */
 352     if( i_read < i_size && b_force )
 353     {
 354         data_packet_t *p_old = p_pk;
 355         int           i_missing = i_size - i_read;
 356
 357         p_pk = input_NewPacket( s->p_input->p_method_data, i_size );
 358         if( p_pk == NULL )
 359         {
 360             input_DeletePacket( s->p_input->p_method_data, p_old );
 361             return NULL;
 362         }
 363         p_pk->p_payload_end = p_pk->p_payload_start + i_size;
 364         memcpy( p_pk->p_payload_start, p_old->p_payload_start, i_read );
 365         input_DeletePacket( s->p_input->p_method_data, p_old );
 366
 367         if( stream_Read( s, &p_pk->p_payload_start[i_read], i_missing )
 368             < i_missing )
 369         {
 370             input_DeletePacket( s->p_input->p_method_data, p_pk );
 371             return NULL;
 372         }
 373     }
 374
 375     return p_pk;
 376 }