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

    chd.h

    MAME Compressed Hunks of Data file format

****************************************************************************

    Copyright Aaron Giles
    All rights reserved.

    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions are 
    met:

        * Redistributions of source code must retain the above copyright
          notice, this list of conditions and the following disclaimer.
        * Redistributions in binary form must reproduce the above copyright
          notice, this list of conditions and the following disclaimer in 
          the documentation and/or other materials provided with the 
          distribution.
        * Neither the name 'MAME' nor the names of its contributors may be 
          used to endorse or promote products derived from this software 
          without specific prior written permission.

    THIS SOFTWARE IS PROVIDED BY AARON GILES ''AS IS'' AND ANY EXPRESS OR 
    IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 
    WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
    DISCLAIMED. IN NO EVENT SHALL AARON GILES BE LIABLE FOR ANY DIRECT, 
    INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
    (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 
    SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 
    HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 
    STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
    IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
    POSSIBILITY OF SUCH DAMAGE.

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

#pragma once

#ifndef __CHD_H__
#define __CHD_H__

#include "osdcore.h"
#include "bitmap.h"
#include "corefile.h"
#include "avcomp.h"


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

    Compressed Hunks of Data header format. All numbers are stored in
    Motorola (big-endian) byte ordering. The header is 76 (V1) or 80 (V2)
    bytes long.

    V1 header:

    [  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 hunksize;      // 512-byte sectors per hunk
    [ 28] UINT32 totalhunks;    // total # of hunks 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 of raw data
    [ 60] UINT8  parentmd5[16]; // MD5 checksum of parent file
    [ 76] (V1 header length)

    V2 header:

    [  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 hunksize;      // seclen-byte sectors per hunk
    [ 28] UINT32 totalhunks;    // total # of hunks 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 of raw data
    [ 60] UINT8  parentmd5[16]; // MD5 checksum of parent file
    [ 76] UINT32 seclen;        // number of bytes per sector
    [ 80] (V2 header length)

    V3 header:

    [  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 totalhunks;    // total # of hunks represented
    [ 28] UINT64 logicalbytes;  // logical size of the data (in bytes)
    [ 36] UINT64 metaoffset;    // offset to the first blob of metadata
    [ 44] UINT8  md5[16];       // MD5 checksum of raw data
    [ 60] UINT8  parentmd5[16]; // MD5 checksum of parent file
    [ 76] UINT32 hunkbytes;     // number of bytes per hunk
    [ 80] UINT8  sha1[20];      // SHA1 checksum of raw data
    [100] UINT8  parentsha1[20];// SHA1 checksum of parent file
    [120] (V3 header length)

    V4 header:

    [  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 totalhunks;    // total # of hunks represented
    [ 28] UINT64 logicalbytes;  // logical size of the data (in bytes)
    [ 36] UINT64 metaoffset;    // offset to the first blob of metadata
    [ 44] UINT32 hunkbytes;     // number of bytes per hunk
    [ 48] UINT8  sha1[20];      // combined raw+meta SHA1
    [ 68] UINT8  parentsha1[20];// combined raw+meta SHA1 of parent
    [ 88] UINT8  rawsha1[20];   // raw data SHA1
    [108] (V4 header length)

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

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


/***************************************************************************
    CONSTANTS
***************************************************************************/

/* header information */
#define CHD_HEADER_VERSION			4
#define CHD_V1_HEADER_SIZE			76
#define CHD_V2_HEADER_SIZE			80
#define CHD_V3_HEADER_SIZE			120
#define CHD_V4_HEADER_SIZE			108
#define CHD_MAX_HEADER_SIZE			CHD_V4_HEADER_SIZE

/* checksumming information */
#define CHD_MD5_BYTES				16
#define CHD_SHA1_BYTES				20

/* CHD global flags */
#define CHDFLAGS_HAS_PARENT			0x00000001
#define CHDFLAGS_IS_WRITEABLE		0x00000002
#define CHDFLAGS_UNDEFINED			0xfffffffc

/* compression types */
#define CHDCOMPRESSION_NONE			0
#define CHDCOMPRESSION_ZLIB			1
#define CHDCOMPRESSION_ZLIB_PLUS	2
#define CHDCOMPRESSION_AV			3

/* A/V codec configuration parameters */
#define AV_CODEC_COMPRESS_CONFIG	1
#define AV_CODEC_DECOMPRESS_CONFIG	2

/* metadata parameters */
#define CHDMETATAG_WILDCARD			0
#define CHD_METAINDEX_APPEND		((UINT32)-1)

/* metadata flags */
#define CHD_MDFLAGS_CHECKSUM		0x01		/* indicates data is checksummed */

/* standard hard disk metadata */
#define HARD_DISK_METADATA_TAG		0x47444444	/* 'GDDD' */
#define HARD_DISK_METADATA_FORMAT	"CYLS:%d,HEADS:%d,SECS:%d,BPS:%d"

/* hard disk identify information */
#define HARD_DISK_IDENT_METADATA_TAG 0x49444e54 /* 'IDNT' */

/* hard disk key information */
#define HARD_DISK_KEY_METADATA_TAG	0x4b455920  /* 'KEY '  */

/* pcmcia CIS information */
#define PCMCIA_CIS_METADATA_TAG		0x43495320  /* 'CIS '  */

/* standard CD-ROM metadata */
#define CDROM_OLD_METADATA_TAG		0x43484344	/* 'CHCD' */
#define CDROM_TRACK_METADATA_TAG	0x43485452	/* 'CHTR' */
#define CDROM_TRACK_METADATA_FORMAT	"TRACK:%d TYPE:%s SUBTYPE:%s FRAMES:%d"

/* standard A/V metadata */
#define AV_METADATA_TAG				0x41564156	/* 'AVAV' */
#define AV_METADATA_FORMAT			"FPS:%d.%06d WIDTH:%d HEIGHT:%d INTERLACED:%d CHANNELS:%d SAMPLERATE:%d"

/* A/V laserdisc frame metadata */
#define AV_LD_METADATA_TAG			0x41564C44	/* 'AVLD' */

/* CHD open values */
#define CHD_OPEN_READ				1
#define CHD_OPEN_READWRITE			2

/* error types */
enum _chd_error
{
	CHDERR_NONE,
	CHDERR_NO_INTERFACE,
	CHDERR_OUT_OF_MEMORY,
	CHDERR_INVALID_FILE,
	CHDERR_INVALID_PARAMETER,
	CHDERR_INVALID_DATA,
	CHDERR_FILE_NOT_FOUND,
	CHDERR_REQUIRES_PARENT,
	CHDERR_FILE_NOT_WRITEABLE,
	CHDERR_READ_ERROR,
	CHDERR_WRITE_ERROR,
	CHDERR_CODEC_ERROR,
	CHDERR_INVALID_PARENT,
	CHDERR_HUNK_OUT_OF_RANGE,
	CHDERR_DECOMPRESSION_ERROR,
	CHDERR_COMPRESSION_ERROR,
	CHDERR_CANT_CREATE_FILE,
	CHDERR_CANT_VERIFY,
	CHDERR_NOT_SUPPORTED,
	CHDERR_METADATA_NOT_FOUND,
	CHDERR_INVALID_METADATA_SIZE,
	CHDERR_UNSUPPORTED_VERSION,
	CHDERR_VERIFY_INCOMPLETE,
	CHDERR_INVALID_METADATA,
	CHDERR_INVALID_STATE,
	CHDERR_OPERATION_PENDING,
	CHDERR_NO_ASYNC_OPERATION,
	CHDERR_UNSUPPORTED_FORMAT
};
typedef enum _chd_error chd_error;



/***************************************************************************
    TYPE DEFINITIONS
***************************************************************************/

/* opaque types */
typedef struct _chd_file chd_file;


/* extract header structure (NOT the on-disk header structure) */
typedef struct _chd_header chd_header;
struct _chd_header
{
	UINT32		length;						/* length of header data */
	UINT32		version;					/* drive format version */
	UINT32		flags;						/* flags field */
	UINT32		compression;				/* compression type */
	UINT32		hunkbytes;					/* number of bytes per hunk */
	UINT32		totalhunks;					/* total # of hunks represented */
	UINT64		logicalbytes;				/* logical size of the data */
	UINT64		metaoffset;					/* offset in file of first metadata */
	UINT8		md5[CHD_MD5_BYTES];			/* overall MD5 checksum */
	UINT8		parentmd5[CHD_MD5_BYTES];	/* overall MD5 checksum of parent */
	UINT8		sha1[CHD_SHA1_BYTES];		/* overall SHA1 checksum */
	UINT8		rawsha1[CHD_SHA1_BYTES];	/* SHA1 checksum of raw data */
	UINT8		parentsha1[CHD_SHA1_BYTES];	/* overall SHA1 checksum of parent */

	UINT32		obsolete_cylinders;			/* obsolete field -- do not use! */
	UINT32		obsolete_sectors;			/* obsolete field -- do not use! */
	UINT32		obsolete_heads;				/* obsolete field -- do not use! */
	UINT32		obsolete_hunksize;			/* obsolete field -- do not use! */
};


/* structure for returning information about a verification pass */
typedef struct _chd_verify_result chd_verify_result;
struct _chd_verify_result
{
	UINT8		md5[CHD_MD5_BYTES];			/* overall MD5 checksum */
	UINT8		sha1[CHD_SHA1_BYTES];		/* overall SHA1 checksum */
	UINT8		rawsha1[CHD_SHA1_BYTES];	/* SHA1 checksum of raw data */
	UINT8		metasha1[CHD_SHA1_BYTES];	/* SHA1 checksum of metadata */
};



/***************************************************************************
    FUNCTION PROTOTYPES
***************************************************************************/


/* ----- CHD file management ----- */

/* create a new CHD file fitting the given description */
chd_error chd_create(const char *filename, UINT64 logicalbytes, UINT32 hunkbytes, UINT32 compression, chd_file *parent);

/* same as chd_create(), but accepts an already-opened core_file object */
chd_error chd_create_file(core_file *file, UINT64 logicalbytes, UINT32 hunkbytes, UINT32 compression, chd_file *parent);

/* open an existing CHD file */
chd_error chd_open(const char *filename, int mode, chd_file *parent, chd_file **chd);

/* same as chd_open(), but accepts an already-opened core_file object */
chd_error chd_open_file(core_file *file, int mode, chd_file *parent, chd_file **chd);

/* close a CHD file */
void chd_close(chd_file *chd);

/* return the associated core_file */
core_file *chd_core_file(chd_file *chd);

/* return an error string for the given CHD error */
const char *chd_error_string(chd_error err);



/* ----- CHD header management ----- */

/* return a pointer to the extracted CHD header data */
const chd_header *chd_get_header(chd_file *chd);

/* set a modified header */
chd_error chd_set_header(const char *filename, const chd_header *header);

/* same as chd_set_header(), but accepts an already-opened core_file object */
chd_error chd_set_header_file(core_file *file, const chd_header *header);



/* ----- core data read/write ----- */

/* read one hunk from the CHD file */
chd_error chd_read(chd_file *chd, UINT32 hunknum, void *buffer);

/* read one hunk from the CHD file asynchronously */
chd_error chd_read_async(chd_file *chd, UINT32 hunknum, void *buffer);

/* write one hunk to a CHD file */
chd_error chd_write(chd_file *chd, UINT32 hunknum, const void *buffer);

/* write one hunk to a CHD file asynchronously */
chd_error chd_write_async(chd_file *chd, UINT32 hunknum, const void *buffer);

/* wait for a previously issued async read/write to complete and return the error */
chd_error chd_async_complete(chd_file *chd);



/* ----- metadata management ----- */

/* get indexed metadata of a particular sort */
chd_error chd_get_metadata(chd_file *chd, UINT32 searchtag, UINT32 searchindex, void *output, UINT32 outputlen, UINT32 *resultlen, UINT32 *resulttag, UINT8 *resultflags);

/* set indexed metadata of a particular sort */
chd_error chd_set_metadata(chd_file *chd, UINT32 metatag, UINT32 metaindex, const void *inputbuf, UINT32 inputlen, UINT8 flags);

/* clone all of the metadata from one CHD to another */
chd_error chd_clone_metadata(chd_file *source, chd_file *dest);



/* ----- compression management ----- */

/* begin compressing data to a CHD */
chd_error chd_compress_begin(chd_file *chd);

/* compress the next hunk of data */
chd_error chd_compress_hunk(chd_file *chd, const void *data, double *curratio);

/* finish compressing data to a CHD */
chd_error chd_compress_finish(chd_file *chd, int write_protect);



/* ----- verification management ----- */

/* begin verifying a CHD */
chd_error chd_verify_begin(chd_file *chd);

/* verify a single hunk of data */
chd_error chd_verify_hunk(chd_file *chd);

/* finish verifying a CHD, returning the computed MD5 and SHA1 */
chd_error chd_verify_finish(chd_file *chd, chd_verify_result *result);



/* ----- codec interfaces ----- */

/* set internal codec parameters */
chd_error chd_codec_config(chd_file *chd, int param, void *config);

/* return a string description of a codec */
const char *chd_get_codec_name(UINT32 codec);


#endif /* __CHD_H__ */
