src/input/stream_memory.c

   1 /*****************************************************************************
   2  * stream_memory.c: stream_t wrapper around memory buffer
   3  *****************************************************************************
   4  * Copyright (C) 1999-2008 VLC authors and VideoLAN
   5  * $Id$
   6  *
   7  * Authors: Sigmund Augdal Helberg <dnumgis@videolan.org>
   8  *
   9  * This program is free software; you can redistribute it and/or modify it
  10  * under the terms of the GNU Lesser General Public License as published by
  11  * the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public License
  20  * along with this program; if not, write to the Free Software Foundation,
  21  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  22  *****************************************************************************/
  23
  24 #ifdef HAVE_CONFIG_H
  25 # include "config.h"
  26 #endif
  27
  28 #include "stream.h"
  29
  30 struct stream_sys_t
  31 {
  32     size_t    i_pos;      /* Current reading offset */
  33     size_t    i_size;
  34     uint8_t  *p_buffer;
  35 };
  36
  37 static ssize_t Read( stream_t *, void *p_read, size_t i_read );
  38 static int Seek( stream_t *, uint64_t );
  39 static int  Control( stream_t *, int i_query, va_list );
  40
  41 static void stream_MemoryPreserveDelete(stream_t *s)
  42 {
  43     free(s->p_sys);
  44 }
  45
  46 static void stream_MemoryDelete(stream_t *s)
  47 {
  48     stream_sys_t *sys = s->p_sys;
  49
  50     free(sys->p_buffer);
  51     stream_MemoryPreserveDelete(s);
  52 }
  53
  54 stream_t *(vlc_stream_MemoryNew)(vlc_object_t *p_this, uint8_t *p_buffer,
  55                                  size_t i_size, bool preserve)
  56 {
  57     stream_t *s = vlc_stream_CommonNew( p_this,
  58                                         preserve ? stream_MemoryPreserveDelete
  59                                                  : stream_MemoryDelete );
  60     stream_sys_t *p_sys;
  61
  62     if( !s )
  63         return NULL;
  64
  65     s->p_sys = p_sys = malloc( sizeof( stream_sys_t ) );
  66     if( !s->p_sys )
  67     {
  68         stream_CommonDelete( s );
  69         return NULL;
  70     }
  71     p_sys->i_pos = 0;
  72     p_sys->i_size = i_size;
  73     p_sys->p_buffer = p_buffer;
  74
  75     s->pf_read    = Read;
  76     s->pf_seek    = Seek;
  77     s->pf_control = Control;
  78
  79     return s;
  80 }
  81
  82 /****************************************************************************
  83  * AStreamControl:
  84  ****************************************************************************/
  85 static int Control( stream_t *s, int i_query, va_list args )
  86 {
  87     stream_sys_t *p_sys = s->p_sys;
  88
  89     uint64_t   *pi_64;
  90
  91     switch( i_query )
  92     {
  93         case STREAM_GET_SIZE:
  94             pi_64 = va_arg( args, uint64_t * );
  95             *pi_64 = p_sys->i_size;
  96             break;
  97
  98         case STREAM_CAN_SEEK:
  99         case STREAM_CAN_FASTSEEK:
 100         case STREAM_CAN_PAUSE:
 101         case STREAM_CAN_CONTROL_PACE:
 102             *va_arg( args, bool * ) = true;
 103             break;
 104
 105         case STREAM_GET_PTS_DELAY:
 106             *va_arg( args, int64_t * ) = 0;
 107             break;
 108
 109         case STREAM_GET_TITLE_INFO:
 110         case STREAM_GET_TITLE:
 111         case STREAM_GET_SEEKPOINT:
 112         case STREAM_GET_META:
 113         case STREAM_GET_CONTENT_TYPE:
 114         case STREAM_GET_SIGNAL:
 115         case STREAM_SET_TITLE:
 116         case STREAM_SET_SEEKPOINT:
 117             return VLC_EGENERIC;
 118
 119         case STREAM_SET_PAUSE_STATE:
 120             break; /* nothing to do */
 121
 122         case STREAM_SET_PRIVATE_ID_STATE:
 123         case STREAM_SET_PRIVATE_ID_CA:
 124         case STREAM_GET_PRIVATE_ID_STATE:
 125             msg_Err( s, "Hey, what are you thinking? "
 126                      "DO NOT USE PRIVATE STREAM CONTROLS!!!" );
 127             return VLC_EGENERIC;
 128
 129         default:
 130             msg_Err( s, "invalid vlc_stream_vaControl query=0x%x", i_query );
 131             return VLC_EGENERIC;
 132     }
 133     return VLC_SUCCESS;
 134 }
 135
 136 static ssize_t Read( stream_t *s, void *p_read, size_t i_read )
 137 {
 138     stream_sys_t *p_sys = s->p_sys;
 139
 140     if( i_read > p_sys->i_size - p_sys->i_pos )
 141         i_read = p_sys->i_size - p_sys->i_pos;
 142     if ( p_read )
 143         memcpy( p_read, p_sys->p_buffer + p_sys->i_pos, i_read );
 144     p_sys->i_pos += i_read;
 145     return i_read;
 146 }
 147
 148 static int Seek( stream_t *s, uint64_t offset )
 149 {
 150     stream_sys_t *p_sys = s->p_sys;
 151
 152     if( offset > p_sys->i_size )
 153         offset = p_sys->i_size;
 154
 155     p_sys->i_pos = offset;
 156     return VLC_SUCCESS;
 157 }