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/*****************************************************************************
* nsc.c: NSC file demux and encoding decoder
*****************************************************************************
* Copyright (C) 2005 VLC authors and VideoLAN
* $Id$
*
* Authors: Derk-Jan Hartman <hartman at videolan dot org>
* based on work from Jon Lech Johansen <jon@nanocrew.net>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
*****************************************************************************/
/*****************************************************************************
* Preamble
*****************************************************************************/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <vlc_common.h>
#include <vlc_plugin.h>
#include <vlc_demux.h>
#include <vlc_charset.h>
#include <ctype.h>
#define MAX_LINE 16024
/*****************************************************************************
* Module descriptor
*****************************************************************************/
static int DemuxOpen ( vlc_object_t * );
static void DemuxClose ( vlc_object_t * );
vlc_module_begin ()
set_description( N_("Windows Media NSC metademux") )
set_category( CAT_INPUT )
set_subcategory( SUBCAT_INPUT_DEMUX )
set_capability( "demux", 3 )
set_callbacks( DemuxOpen, DemuxClose )
vlc_module_end ()
static int Demux ( demux_t *p_demux );
static int Control( demux_t *p_demux, int i_query, va_list args );
static const unsigned char inverse[ 128 ] =
{
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0xFF, 0xFF,
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F, 0x10,
0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1A, 0x1B, 0x1C,
0x1D, 0x1E, 0x1F, 0x20, 0x21, 0x22, 0x23, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
0xFF, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E,
0x2F, 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3A,
0x3B, 0x3C, 0x3D, 0x3E, 0xFF, 0x3F, 0xFF, 0xFF
};
static int load_byte( unsigned char encoding_type,
unsigned char *output, char **input,
unsigned char *j, unsigned char *k )
{
*output = 0;
if( encoding_type == 1 )
{
if( isxdigit( (unsigned char)**input ) == 0 )
return -1;
if( isdigit( (unsigned char)**input ) == 0 )
*output = (toupper( (unsigned char)**input ) - 7) * 16;
else
*output = **input * 16;
(*input)++;
if( isxdigit( (unsigned char)**input ) == 0 )
return -1;
if( isdigit( (unsigned char)**input ) == 0 )
*output |= toupper( (unsigned char)**input ) - 0x37;
else
*output |= **input - 0x30;
(*input)++;
}
else if( encoding_type == 2 )
{
unsigned char **uinput = (unsigned char **)input;
if( **uinput > 127 || inverse[ **uinput ] == 0xFF )
return -1;
if( *k == 0 )
{
if( (*uinput)[ 1 ] > 127 || inverse[ (*uinput)[ 1 ] ] == 0xFF )
return -1;
*output = (inverse[ (*uinput)[ 0 ] ] * 4) |
(inverse[ (*uinput)[ 1 ] ] / 16);
*j = inverse[ (*uinput)[ 1 ] ] * 16;
*k = 4;
(*uinput) += 2;
}
else if( *k == 2 )
{
*output = *j | inverse[ **uinput ];
*j = 0;
*k = 0;
(*uinput)++;
}
else if( *k == 4 )
{
*output = (inverse[ **uinput ] / 4) | *j;
*j = inverse[ **uinput ] * 64;
*k = 2;
(*uinput)++;
}
}
return 0;
}
static char *nscdec( vlc_object_t *p_demux, char* p_encoded )
{
unsigned int i;
unsigned char tmp;
unsigned char j, k;
unsigned int length;
unsigned char encoding_type;
unsigned char *buf16;
char *buf8;
char *p_input = p_encoded;
if( strlen( p_input ) < 15 )
{
msg_Err( p_demux, "input string less than 15 characters" );
return NULL;
}
if( load_byte( 1, &encoding_type, &p_input, NULL, NULL ) )
{
msg_Err( p_demux, "unable to get NSC encoding type" );
return NULL;
}
if( encoding_type != 1 && encoding_type != 2 )
{
msg_Err( p_demux, "encoding type %d is not supported",
encoding_type );
return NULL;
}
j = k = 0;
if( load_byte( encoding_type, &tmp, &p_input, &j, &k ) )
{
msg_Err( p_demux, "load_byte failed" );
return NULL;
}
for( i = 0; i < 4; i++ )
{
if( load_byte( encoding_type, &tmp, &p_input, &j, &k ) )
{
msg_Err( p_demux, "load_byte failed" );
return NULL;
}
}
length = 0;
for( i = 4; i; i-- )
{
if( load_byte( encoding_type, &tmp, &p_input, &j, &k ) )
{
msg_Err( p_demux, "load_byte failed" );
return NULL;
}
length |= tmp << ((i - 1) * 8);
}
if( length == 0 )
{
msg_Err( p_demux, "Length is 0" );
return NULL;
}
buf16 = malloc( length );
if( buf16 == NULL )
return NULL;
for( i = 0; i < length; i++ )
{
if( load_byte( encoding_type, &buf16[ i ], &p_input, &j, &k ) )
{
msg_Err( p_demux, "load_byte failed" );
free( buf16 );
return NULL;
}
}
buf8 = FromCharset( "UTF-16LE", buf16, length );
free( buf16 );
if( buf8 == NULL )
{
msg_Err( p_demux, "iconv failed" );
return NULL;
}
return buf8;
}
static int DemuxOpen( vlc_object_t * p_this )
{
demux_t *p_demux = (demux_t *)p_this;
const uint8_t *p_peek;
int i_size;
/* Lets check the content to see if this is a NSC file */
i_size = stream_Peek( p_demux->s, &p_peek, MAX_LINE );
i_size -= sizeof("NSC Format Version=") - 1;
if ( i_size > 0 )
{
while ( i_size && strncasecmp( (char *)p_peek, "NSC Format Version=",
(int) sizeof("NSC Format Version=") - 1 ) )
{
p_peek++;
i_size--;
}
if ( !strncasecmp( (char *)p_peek, "NSC Format Version=",
(int) sizeof("NSC Format Version=") -1 ) )
{
p_demux->pf_demux = Demux;
p_demux->pf_control = Control;
return VLC_SUCCESS;
}
}
return VLC_EGENERIC;
}
/*****************************************************************************
* Deactivate: frees unused data
*****************************************************************************/
static void DemuxClose( vlc_object_t *p_this )
{
VLC_UNUSED( p_this );
return;
}
static int ParseLine ( demux_t *p_demux, char *psz_line )
{
char *psz_bol;
char *psz_value;
psz_bol = psz_line;
/* Remove unnecessary tabs or spaces at the beginning of line */
while( *psz_bol == ' ' || *psz_bol == '\t' ||
*psz_bol == '\n' || *psz_bol == '\r' )
{
psz_bol++;
}
psz_value = strchr( psz_bol, '=' );
if( psz_value == NULL )
{
return 0; /* a [Address] or [Formats] line or something else we will ignore */
}
*psz_value = '\0';
psz_value++;
if( !strncasecmp( psz_value, "0x", 2 ) )
{
int i_value;
sscanf( psz_value, "%x", &i_value );
msg_Dbg( p_demux, "%s = %d", psz_bol, i_value );
}
else if( !strncasecmp( psz_bol, "Format", 6 ) )
{
msg_Dbg( p_demux, "%s = asf header", psz_bol );
}
else
{
/* This should be NSC encoded strings in the values */
char *psz_out;
psz_out = nscdec( (vlc_object_t *)p_demux, psz_value );
if( psz_out )
{
msg_Dbg( p_demux, "%s = %s", psz_bol, psz_out );
free( psz_out );
}
}
return VLC_SUCCESS;
}
/*****************************************************************************
* Demux: reads and demuxes data packets
*****************************************************************************
* Returns -1 in case of error, 0 in case of EOF, 1 otherwise
*****************************************************************************/
static int Demux ( demux_t *p_demux )
{
char *psz_line;
while( ( psz_line = stream_ReadLine( p_demux->s ) ) )
{
ParseLine( p_demux, psz_line );
free( psz_line );
}
return VLC_SUCCESS;
}
static int Control( demux_t *p_demux, int i_query, va_list args )
{
VLC_UNUSED( p_demux ); VLC_UNUSED( i_query ); VLC_UNUSED( args );
//FIXME
return VLC_EGENERIC;
}