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/*
* This file is part of libextractor.
* Copyright (C) 2006, 2007, 2012 Vidyut Samanta and Christian Grothoff
*
* libextractor is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published
* by the Free Software Foundation; either version 3, or (at your
* option) any later version.
*
* libextractor 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
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with libextractor; see the file COPYING. If not, write to the
* Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*
*/
/**
* @file plugins/sid_extractor.c
* @brief plugin to support Scream Tracker (S3M) files
* @author Toni Ruottu
* @author Christian Grothoff
*/
#include "platform.h"
#include "extractor.h"
/* SID flags */
#define MUSPLAYER_FLAG 0x01
#define PLAYSID_FLAG 0x02
#define PAL_FLAG 0x04
#define NTSC_FLAG 0x08
#define MOS6581_FLAG 0x10
#define MOS8580_FLAG 0x20
/**
* A "SID word".
*/
typedef char sidwrd[2];
/**
* A "SID long".
*/
typedef char sidlongwrd[4];
/**
* Header of a SID file.
*/
struct header
{
/**
* Magic string.
*/
char magicid[4];
/**
* Version number.
*/
sidwrd sidversion;
/**
* Unknown.
*/
sidwrd dataoffset;
/**
* Unknown.
*/
sidwrd loadaddr;
/**
* Unknown.
*/
sidwrd initaddr;
/**
* Unknown.
*/
sidwrd playaddr;
/**
* Number of songs in file.
*/
sidwrd songs;
/**
* Starting song.
*/
sidwrd firstsong;
/**
* Unknown.
*/
sidlongwrd speed;
/**
* Title of the album.
*/
char title[32];
/**
* Name of the artist.
*/
char artist[32];
/**
* Copyright information.
*/
char copyright[32];
/* version 2 specific fields start */
/**
* Flags
*/
sidwrd flags;
/**
* Unknown.
*/
char startpage;
/**
* Unknown.
*/
char pagelength;
/**
* Unknown.
*/
sidwrd reserved;
};
/**
* Convert a 'sidword' to an integer.
*
* @param data the sidword
* @return corresponding integer value
*/
static int
sidword (const sidwrd data)
{
return (unsigned char) data[0] * 0x100 + (unsigned char) data[1];
}
/**
* Give metadata to LE; return if 'proc' returns non-zero.
*
* @param s metadata value as UTF8
* @param t metadata type to use
*/
#define ADD(s,t) do { if (0 != ec->proc (ec->cls, "sid", t, EXTRACTOR_METAFORMAT_UTF8, "text/plain", s, strlen (s) + 1)) return; } while (0)
/**
* Extract metadata from SID files.
*
* @param ec extraction context
*/
void
EXTRACTOR_sid_extract_method (struct EXTRACTOR_ExtractContext *ec)
{
unsigned int flags;
int version;
char album[33];
char artist[33];
char copyright[33];
char songs[32];
char startingsong[32];
char sidversion[32];
const struct header *head;
void *data;
if ((ssize_t) sizeof (struct header) >
ec->read (ec->cls,
&data,
sizeof (struct header)))
return;
head = data;
/* Check "magic" id bytes */
if ( (0 != memcmp (head->magicid, "PSID", 4)) &&
(0 != memcmp (head->magicid, "RSID", 4)) )
return;
/* Mime-type */
ADD ("audio/prs.sid", EXTRACTOR_METATYPE_MIMETYPE);
/* Version of SID format */
version = sidword (head->sidversion);
snprintf (sidversion,
sizeof (sidversion),
"%d",
version);
ADD (sidversion, EXTRACTOR_METATYPE_FORMAT_VERSION);
/* Get song count */
snprintf (songs,
sizeof (songs),
"%d", sidword (head->songs));
ADD (songs, EXTRACTOR_METATYPE_SONG_COUNT);
/* Get number of the first song to be played */
snprintf (startingsong,
sizeof (startingsong),
"%d",
sidword (head->firstsong));
ADD (startingsong, EXTRACTOR_METATYPE_STARTING_SONG);
/* name, artist, copyright fields */
memcpy (&album, head->title, 32);
album[32] = '\0';
ADD (album, EXTRACTOR_METATYPE_ALBUM);
memcpy (&artist, head->artist, 32);
artist[32] = '\0';
ADD (artist, EXTRACTOR_METATYPE_ARTIST);
memcpy (©right, head->copyright, 32);
copyright[32] = '\0';
ADD (copyright, EXTRACTOR_METATYPE_COPYRIGHT);
if (version < 2)
return;
/* Version 2 specific options follow
*
* Note: Had some troubles understanding specification
* on the flags in version 2. I hope this is correct.
*/
flags = sidword (head->flags);
/* MUS data */
if (0 != (flags & MUSPLAYER_FLAG))
ADD ("Compute!'s Sidplayer", EXTRACTOR_METATYPE_CREATED_BY_SOFTWARE);
/* PlaySID data */
if (0 != (flags & PLAYSID_FLAG))
ADD ("PlaySID", EXTRACTOR_METATYPE_CREATED_BY_SOFTWARE);
/* PAL or NTSC */
if (0 != (flags & NTSC_FLAG))
ADD ("PAL/NTSC", EXTRACTOR_METATYPE_BROADCAST_TELEVISION_SYSTEM);
else if (0 != (flags & PAL_FLAG))
ADD ("PAL", EXTRACTOR_METATYPE_BROADCAST_TELEVISION_SYSTEM);
/* Detect SID Chips suitable for play the files */
if (0 != (flags & MOS8580_FLAG))
ADD ("MOS6581/MOS8580", EXTRACTOR_METATYPE_TARGET_ARCHITECTURE);
else if (0 != (flags & MOS6581_FLAG))
ADD ("MOS6581", EXTRACTOR_METATYPE_TARGET_ARCHITECTURE);
}
/* end of sid_extractor.c */
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