rockbox/lib/rbcodec/codecs/libgme/rom_data.c
Sean Bartell f40bfc9267 Add codecs to librbcodec.
Change-Id: Id7f4717d51ed02d67cb9f9cb3c0ada4a81843f97
Reviewed-on: http://gerrit.rockbox.org/137
Reviewed-by: Nils Wallménius <nils@rockbox.org>
Tested-by: Nils Wallménius <nils@rockbox.org>
2012-04-25 22:13:20 +02:00

68 lines
2 KiB
C

// Game_Music_Emu 0.5.2. http://www.slack.net/~ant/
#include "rom_data.h"
/* Copyright (C) 2003-2006 Shay Green. This module 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
module 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 module; if not, write to the Free Software Foundation,
Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */
#include <string.h>
#include "blargg_source.h"
// Rom_Data
blargg_err_t Rom_load( struct Rom_Data* this, const void* data, long size,
int header_size, void* header_out, int fill )
{
int file_offset = this->pad_size;
this->rom_addr = 0;
this->mask = 0;
this->size = 0;
if ( size <= header_size ) // <= because there must be data after header
return gme_wrong_file_type;
// Read header
memcpy( header_out, data, header_size );
this->file_size = size - header_size;
this->file_data = (byte*) data + header_size;
memset( this->unmapped, fill, this->rom_size );
memcpy( &this->unmapped [file_offset], this->file_data,
this->file_size < this->pad_size ? this->file_size : this->pad_size );
return 0;
}
void Rom_set_addr( struct Rom_Data* this, int addr )
{
this->rom_addr = addr - this->bank_size - pad_extra;
int rounded = (addr + this->file_size + this->bank_size - 1) / this->bank_size * this->bank_size;
if ( rounded <= 0 )
{
rounded = 0;
}
else
{
int shift = 0;
unsigned int max_addr = (unsigned int) (rounded - 1);
while ( max_addr >> shift )
shift++;
this->mask = (1L << shift) - 1;
}
if ( addr < 0 )
addr = 0;
this->size = rounded;
this->rsize_ = rounded - this->rom_addr + pad_extra;
}