mame/src/lib/formats/sorc_dsk.cpp

// license:BSD-3-Clause
// copyright-holders:Robbbert
/*********************************************************************

    formats/sorc_dsk.c

    Exidy Sorcerer floppy-disk images

*********************************************************************/

#include "sorc_dsk.h"
#include "basicdsk.h"

#include <cstring>

static FLOPPY_IDENTIFY(sorc_dsk_identify)
{
	*vote = (floppy_image_size(floppy) == 332640) ? 100 : 0;
	return FLOPPY_ERROR_SUCCESS;
}

static int sorc_get_heads_per_disk(floppy_image_legacy *floppy)
{
	return 1;
}

static int sorc_get_tracks_per_disk(floppy_image_legacy *floppy)
{
	return 77;
}

static uint64_t sorc_translate_offset(floppy_image_legacy *floppy, int track, int head, int sector)
{
	return 270*(16*uint64_t(track+sector));
}

static floperr_t get_offset(floppy_image_legacy *floppy, int head, int track, int sector, bool sector_is_index, uint64_t *offset)
{
	uint64_t offs;
	/* translate the sector to a raw sector */
	if (!sector_is_index)
	{
		sector -= 1;
	}
	/* check to see if we are out of range */
	if ((head != 0) || (track < 0) || (track >= 77) || (sector < 0) || (sector >= 16))
		return FLOPPY_ERROR_SEEKERROR;

	offs = sorc_translate_offset(floppy, track, head, sector);
	if (offset)
		*offset = offs;
	return FLOPPY_ERROR_SUCCESS;
}



static floperr_t internal_sorc_read_sector(floppy_image_legacy *floppy, int head, int track, int sector, bool sector_is_index, void *buffer, size_t buflen)
{
	uint64_t offset;
	floperr_t err;
	err = get_offset(floppy, head, track, sector, sector_is_index, &offset);
	if (err)
		return err;

	floppy_image_read(floppy, buffer, offset, buflen);
	return FLOPPY_ERROR_SUCCESS;
}



static floperr_t internal_sorc_write_sector(floppy_image_legacy *floppy, int head, int track, int sector, bool sector_is_index, const void *buffer, size_t buflen, int ddam)
{
	uint64_t offset;
	floperr_t err;

	err = get_offset(floppy, head, track, sector, sector_is_index, &offset);
	if (err)
		return err;

	floppy_image_write(floppy, buffer, offset, buflen);
	return FLOPPY_ERROR_SUCCESS;
}



static floperr_t sorc_read_sector(floppy_image_legacy *floppy, int head, int track, int sector, void *buffer, size_t buflen)
{
	return internal_sorc_read_sector(floppy, head, track, sector, false, buffer, buflen);
}

static floperr_t sorc_write_sector(floppy_image_legacy *floppy, int head, int track, int sector, const void *buffer, size_t buflen, int ddam)
{
	return internal_sorc_write_sector(floppy, head, track, sector, false, buffer, buflen, ddam);
}

static floperr_t sorc_read_indexed_sector(floppy_image_legacy *floppy, int head, int track, int sector, void *buffer, size_t buflen)
{
	return internal_sorc_read_sector(floppy, head, track, sector, true, buffer, buflen);
}

static floperr_t sorc_write_indexed_sector(floppy_image_legacy *floppy, int head, int track, int sector, const void *buffer, size_t buflen, int ddam)
{
	return internal_sorc_write_sector(floppy, head, track, sector, true, buffer, buflen, ddam);
}

static floperr_t sorc_get_sector_length(floppy_image_legacy *floppy, int head, int track, int sector, uint32_t *sector_length)
{
	floperr_t err;
	err = get_offset(floppy, head, track, sector, false, nullptr);
	if (err)
		return err;

	if (sector_length) {
		*sector_length = 270;
	}
	return FLOPPY_ERROR_SUCCESS;
}



static floperr_t sorc_get_indexed_sector_info(floppy_image_legacy *floppy, int head, int track, int sector_index, int *cylinder, int *side, int *sector, uint32_t *sector_length, unsigned long *flags)
{
	sector_index += 1;
	if (cylinder)
		*cylinder = track;
	if (side)
		*side = head;
	if (sector)
		*sector = sector_index;
	if (flags)
		/* TODO: read DAM or DDAM and determine flags */
		*flags = 0;
	return sorc_get_sector_length(floppy, head, track, sector_index, sector_length);
}


static FLOPPY_CONSTRUCT(sorc_dsk_construct)
{
	struct FloppyCallbacks *callbacks;
	callbacks = floppy_callbacks(floppy);
	callbacks->read_sector = sorc_read_sector;
	callbacks->write_sector = sorc_write_sector;
	callbacks->read_indexed_sector = sorc_read_indexed_sector;
	callbacks->write_indexed_sector = sorc_write_indexed_sector;
	callbacks->get_sector_length = sorc_get_sector_length;
	callbacks->get_heads_per_disk = sorc_get_heads_per_disk;
	callbacks->get_tracks_per_disk = sorc_get_tracks_per_disk;
	callbacks->get_indexed_sector_info = sorc_get_indexed_sector_info;

	return FLOPPY_ERROR_SUCCESS;
}



/* ----------------------------------------------------------------------- */

LEGACY_FLOPPY_OPTIONS_START( sorcerer )
	LEGACY_FLOPPY_OPTION( sorc_dsk, "dsk", "Exidy Sorcerer floppy disk image", sorc_dsk_identify, sorc_dsk_construct, nullptr, nullptr)
LEGACY_FLOPPY_OPTIONS_END