mame32jp/src/harddisk.h

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

        Generic MAME hard disk implementation, with differencing files

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

#include "driver.h"


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

        MAME compressed hard disk header format. All numbers are stored in
        Motorola (big-endian) byte ordering. The header is 76 bytes long.

        [  0] char   tag[8];            // 'MComprHD'
        [  8] UINT32 length;            // length of header (including tag and length fields)
        [ 12] UINT32 version;           // drive format version
        [ 16] UINT32 flags;                     // flags (see below)
        [ 20] UINT32 compression;       // compression type
        [ 24] UINT32 blocksize;         // sectors per block
        [ 28] UINT32 totalblocks;       // total # of block represented
        [ 32] UINT32 cylinders;         // number of cylinders on hard disk
        [ 36] UINT32 heads;                     // number of heads on hard disk
        [ 40] UINT32 sectors;           // number of sectors on hard disk
        [ 44] UINT8  md5[16];           // MD5 checksum for this drive
        [ 60] UINT8  parentmd5[16];     // MD5 checksum for parent drive
        [ 76] (header length)

        Flags:
                0x00000001 - set if this drive has a parent
                0x00000002 - set if this drive allows writes

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

/*************************************
 *
 *      Constants
 *
 *************************************/

#define HARD_DISK_HEADER_SIZE           76
#define HARD_DISK_HEADER_VERSION        1

#define HARD_DISK_SECTOR_SIZE           512

#define HDFLAGS_HAS_PARENT                      0x00000001
#define HDFLAGS_IS_WRITEABLE            0x00000002

#define HDCOMPRESSION_NONE                      0
#define HDCOMPRESSION_ZLIB                      1
#define HDCOMPRESSION_MAX                       2

enum
{
        HDERR_NONE,
        HDERR_NO_INTERFACE,
        HDERR_OUT_OF_MEMORY,
        HDERR_INVALID_FILE,
        HDERR_INVALID_PARAMETER,
        HDERR_INVALID_DATA,
        HDERR_FILE_NOT_FOUND,
        HDERR_REQUIRES_PARENT,
        HDERR_FILE_NOT_WRITEABLE,
        HDERR_READ_ERROR,
        HDERR_WRITE_ERROR,
        HDERR_CODEC_ERROR,
        HDERR_INVALID_PARENT,
        HDERR_SECTOR_OUT_OF_RANGE,
        HDERR_DECOMPRESSION_ERROR,
        HDERR_COMPRESSION_ERROR,
        HDERR_CANT_CREATE_FILE
};


/*************************************
 *
 *      Type definitions
 *
 *************************************/

struct hard_disk_header
{
        UINT32  length;                         /* length of header data */
        UINT32  version;                        /* drive format version */
        UINT32  flags;                          /* flags field */
        UINT32  compression;            /* compression type */
        UINT32  blocksize;                      /* sectors per block */
        UINT32  totalblocks;            /* total # of blocks represented */
        UINT32  cylinders;                      /* number of cylinders on hard disk */
        UINT32  heads;                          /* number of heads on hard disk */
        UINT32  sectors;                        /* number of sectors on hard disk */
        UINT8   md5[16];                        /* MD5 checksum for this drive */
        UINT8   parentmd5[16];          /* MD5 checksum for parent drive */
};


struct hard_disk_interface
{
        void *(*open)(const char *filename, const char *mode);
        void (*close)(void *file);
        UINT32 (*read)(void *file, UINT64 offset, UINT32 count, void *buffer);
        UINT32 (*write)(void *file, UINT64 offset, UINT32 count, const void *buffer);
};


/*************************************
 *
 *      Prototypes
 *
 *************************************/

void hard_disk_set_interface(struct hard_disk_interface *interface);

int hard_disk_create(const char *filename, const struct hard_disk_header *header);
void *hard_disk_open(const char *filename, int writeable, void *parent);
void hard_disk_close(void *disk);
void hard_disk_close_all(void);

UINT32 hard_disk_read(void *disk, UINT32 lbasector, UINT32 numsectors, void *buffer);
UINT32 hard_disk_write(void *disk, UINT32 lbasector, UINT32 numsectors, const void *buffer);

int hard_disk_get_last_error(void);
const struct hard_disk_header *hard_disk_get_header(void *disk);

int hard_disk_compress(const char *rawfile, UINT32 offset, const char *newfile, const struct hard_disk_header *header, const char *difffile, void (*progress)(const char *, ...));