[pcsx_rearmed.git] / deps / libchdr / chd.h

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

    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__

#ifdef __cplusplus
extern "C" {
#endif

#include "coretypes.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

   =========================================================================

    V5 header:

    [  0] char   tag[8];        // 'MComprHD'
    [  8] uint32_t length;        // length of header (including tag and length fields)
    [ 12] uint32_t version;       // drive format version
    [ 16] uint32_t compressors[4];// which custom compressors are used?
    [ 32] uint64_t logicalbytes;  // logical size of the data (in bytes)
    [ 40] uint64_t mapoffset;     // offset to the map
    [ 48] uint64_t metaoffset;    // offset to the first blob of metadata
    [ 56] uint32_t hunkbytes;     // number of bytes per hunk (512k maximum)
    [ 60] uint32_t unitbytes;     // number of bytes per unit within each hunk
    [ 64] uint8_t  rawsha1[20];   // raw data SHA1
    [ 84] uint8_t  sha1[20];      // combined raw+meta SHA1
    [104] uint8_t  parentsha1[20];// combined raw+meta SHA1 of parent
    [124] (V5 header length)

    If parentsha1 != 0, we have a parent (no need for flags)
    If compressors[0] == 0, we are uncompressed (including maps)

    V5 uncompressed map format:

    [  0] uint32_t offset;        // starting offset / hunk size

    V5 compressed map format header:

    [  0] uint32_t length;        // length of compressed map
    [  4] UINT48 datastart;     // offset of first block
    [ 10] uint16_t crc;           // crc-16 of the map
    [ 12] uint8_t lengthbits;     // bits used to encode complength
    [ 13] uint8_t hunkbits;       // bits used to encode self-refs
    [ 14] uint8_t parentunitbits; // bits used to encode parent unit refs
    [ 15] uint8_t reserved;       // future use
    [ 16] (compressed header length)

    Each compressed map entry, once expanded, looks like:

    [  0] uint8_t compression;    // compression type
    [  1] UINT24 complength;    // compressed length
    [  4] UINT48 offset;        // offset
    [ 10] uint16_t crc;           // crc-16 of the data

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


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

/* header information */
#define CHD_HEADER_VERSION			5
#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_V5_HEADER_SIZE          124

#define CHD_MAX_HEADER_SIZE			CHD_V5_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"
#define CDROM_TRACK_METADATA2_TAG	0x43485432	/* 'CHT2' */
#define CDROM_TRACK_METADATA2_FORMAT	"TRACK:%d TYPE:%s SUBTYPE:%s FRAMES:%d PREGAP:%d PGTYPE:%s PGSUB:%s POSTGAP:%d"
#define GDROM_TRACK_METADATA_TAG	0x43484744	/* 'CHTD' */
#define GDROM_TRACK_METADATA_FORMAT	"TRACK:%d TYPE:%s SUBTYPE:%s FRAMES:%d PAD:%d PREGAP:%d PGTYPE:%s PGSUB:%s POSTGAP:%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[4];				/* 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 */
	UINT64		mapoffset;					/* TOOD V5 */
	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		unitbytes;					/* TODO V5 */
	UINT64		unitcount;					/* TODO V5 */	
    UINT32      hunkcount;                  /* TODO V5 */

    // map information
    UINT32      mapentrybytes;              // length of each entry in a map (V5)
    UINT8*      rawmap;                     // raw map data

	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);

/* precache underlying file */
chd_error chd_precache(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);


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

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


/* ----- 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);


/* ----- 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);

#ifdef __cplusplus
}
#endif

#endif /* __CHD_H__ */
Commit	Line	Data
ce188d4d	1	/***************************************************************************
	2
	3	chd.h
	4
	5	MAME Compressed Hunks of Data file format
	6
	7	****************************************************************************
	8
	9	Copyright Aaron Giles
	10	All rights reserved.
	11
	12	Redistribution and use in source and binary forms, with or without
	13	modification, are permitted provided that the following conditions are
	14	met:
	15
	16	* Redistributions of source code must retain the above copyright
	17	notice, this list of conditions and the following disclaimer.
	18	* Redistributions in binary form must reproduce the above copyright
	19	notice, this list of conditions and the following disclaimer in
	20	the documentation and/or other materials provided with the
	21	distribution.
	22	* Neither the name 'MAME' nor the names of its contributors may be
	23	used to endorse or promote products derived from this software
	24	without specific prior written permission.
	25
	26	THIS SOFTWARE IS PROVIDED BY AARON GILES ''AS IS'' AND ANY EXPRESS OR
	27	IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
	28	WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
	29	DISCLAIMED. IN NO EVENT SHALL AARON GILES BE LIABLE FOR ANY DIRECT,
	30	INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
	31	(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
	32	SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	33	HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
	34	STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
	35	IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
	36	POSSIBILITY OF SUCH DAMAGE.
	37
	38	***************************************************************************/
	39
	40	#pragma once
	41
	42	#ifndef __CHD_H__
	43	#define __CHD_H__
	44
	45	#ifdef __cplusplus
	46	extern "C" {
	47	#endif
	48
	49	#include "coretypes.h"
	50
	51
	52	/***************************************************************************
	53
	54	Compressed Hunks of Data header format. All numbers are stored in
	55	Motorola (big-endian) byte ordering. The header is 76 (V1) or 80 (V2)
	56	bytes long.
	57
	58	V1 header:
	59
	60	[ 0] char tag[8]; // 'MComprHD'
	61	[ 8] UINT32 length; // length of header (including tag and length fields)
	62	[ 12] UINT32 version; // drive format version
	63	[ 16] UINT32 flags; // flags (see below)
	64	[ 20] UINT32 compression; // compression type
65	[ 24] UINT32 hunksize; // 512-byte sectors per hunk
66	[ 28] UINT32 totalhunks; // total # of hunks represented
67	[ 32] UINT32 cylinders; // number of cylinders on hard disk
68	[ 36] UINT32 heads; // number of heads on hard disk
69	[ 40] UINT32 sectors; // number of sectors on hard disk
70	[ 44] UINT8 md5[16]; // MD5 checksum of raw data
71	[ 60] UINT8 parentmd5[16]; // MD5 checksum of parent file
72	[ 76] (V1 header length)
73
74	V2 header:
75
76	[ 0] char tag[8]; // 'MComprHD'
77	[ 8] UINT32 length; // length of header (including tag and length fields)
78	[ 12] UINT32 version; // drive format version
79	[ 16] UINT32 flags; // flags (see below)
80	[ 20] UINT32 compression; // compression type
81	[ 24] UINT32 hunksize; // seclen-byte sectors per hunk
82	[ 28] UINT32 totalhunks; // total # of hunks represented
83	[ 32] UINT32 cylinders; // number of cylinders on hard disk
84	[ 36] UINT32 heads; // number of heads on hard disk
85	[ 40] UINT32 sectors; // number of sectors on hard disk
86	[ 44] UINT8 md5[16]; // MD5 checksum of raw data
87	[ 60] UINT8 parentmd5[16]; // MD5 checksum of parent file
88	[ 76] UINT32 seclen; // number of bytes per sector
89	[ 80] (V2 header length)
90
91	V3 header:
92
93	[ 0] char tag[8]; // 'MComprHD'
94	[ 8] UINT32 length; // length of header (including tag and length fields)
95	[ 12] UINT32 version; // drive format version
96	[ 16] UINT32 flags; // flags (see below)
97	[ 20] UINT32 compression; // compression type
98	[ 24] UINT32 totalhunks; // total # of hunks represented
99	[ 28] UINT64 logicalbytes; // logical size of the data (in bytes)
100	[ 36] UINT64 metaoffset; // offset to the first blob of metadata
101	[ 44] UINT8 md5[16]; // MD5 checksum of raw data
102	[ 60] UINT8 parentmd5[16]; // MD5 checksum of parent file
103	[ 76] UINT32 hunkbytes; // number of bytes per hunk
104	[ 80] UINT8 sha1[20]; // SHA1 checksum of raw data
105	[100] UINT8 parentsha1[20];// SHA1 checksum of parent file
106	[120] (V3 header length)
107
108	V4 header:
109
110	[ 0] char tag[8]; // 'MComprHD'
111	[ 8] UINT32 length; // length of header (including tag and length fields)
112	[ 12] UINT32 version; // drive format version
113	[ 16] UINT32 flags; // flags (see below)
114	[ 20] UINT32 compression; // compression type
115	[ 24] UINT32 totalhunks; // total # of hunks represented
116	[ 28] UINT64 logicalbytes; // logical size of the data (in bytes)
117	[ 36] UINT64 metaoffset; // offset to the first blob of metadata
118	[ 44] UINT32 hunkbytes; // number of bytes per hunk
119	[ 48] UINT8 sha1[20]; // combined raw+meta SHA1
120	[ 68] UINT8 parentsha1[20];// combined raw+meta SHA1 of parent
121	[ 88] UINT8 rawsha1[20]; // raw data SHA1
122	[108] (V4 header length)
123
124	Flags:
125	0x00000001 - set if this drive has a parent
126	0x00000002 - set if this drive allows writes
127
128	=========================================================================
129
130	V5 header:
131
132	[ 0] char tag[8]; // 'MComprHD'
133	[ 8] uint32_t length; // length of header (including tag and length fields)
134	[ 12] uint32_t version; // drive format version
135	[ 16] uint32_t compressors[4];// which custom compressors are used?
136	[ 32] uint64_t logicalbytes; // logical size of the data (in bytes)
137	[ 40] uint64_t mapoffset; // offset to the map
138	[ 48] uint64_t metaoffset; // offset to the first blob of metadata
139	[ 56] uint32_t hunkbytes; // number of bytes per hunk (512k maximum)
140	[ 60] uint32_t unitbytes; // number of bytes per unit within each hunk
141	[ 64] uint8_t rawsha1[20]; // raw data SHA1
142	[ 84] uint8_t sha1[20]; // combined raw+meta SHA1
143	[104] uint8_t parentsha1[20];// combined raw+meta SHA1 of parent
144	[124] (V5 header length)
145
146	If parentsha1 != 0, we have a parent (no need for flags)
147	If compressors[0] == 0, we are uncompressed (including maps)
148
149	V5 uncompressed map format:
150
151	[ 0] uint32_t offset; // starting offset / hunk size
152
153	V5 compressed map format header:
154
155	[ 0] uint32_t length; // length of compressed map
156	[ 4] UINT48 datastart; // offset of first block
157	[ 10] uint16_t crc; // crc-16 of the map
158	[ 12] uint8_t lengthbits; // bits used to encode complength
159	[ 13] uint8_t hunkbits; // bits used to encode self-refs
160	[ 14] uint8_t parentunitbits; // bits used to encode parent unit refs
161	[ 15] uint8_t reserved; // future use
162	[ 16] (compressed header length)
163
164	Each compressed map entry, once expanded, looks like:
165
166	[ 0] uint8_t compression; // compression type
167	[ 1] UINT24 complength; // compressed length
168	[ 4] UINT48 offset; // offset
169	[ 10] uint16_t crc; // crc-16 of the data
170
171	***************************************************************************/
172
173
174	/***************************************************************************
175	CONSTANTS
176	***************************************************************************/
177
178	/* header information */
179	#define CHD_HEADER_VERSION 5
180	#define CHD_V1_HEADER_SIZE 76
181	#define CHD_V2_HEADER_SIZE 80
182	#define CHD_V3_HEADER_SIZE 120
183	#define CHD_V4_HEADER_SIZE 108
184	#define CHD_V5_HEADER_SIZE 124
185
186	#define CHD_MAX_HEADER_SIZE CHD_V5_HEADER_SIZE
187
188	/* checksumming information */
189	#define CHD_MD5_BYTES 16
190	#define CHD_SHA1_BYTES 20
191
192	/* CHD global flags */
193	#define CHDFLAGS_HAS_PARENT 0x00000001
194	#define CHDFLAGS_IS_WRITEABLE 0x00000002
195	#define CHDFLAGS_UNDEFINED 0xfffffffc
196
197	/* compression types */
198	#define CHDCOMPRESSION_NONE 0
199	#define CHDCOMPRESSION_ZLIB 1
200	#define CHDCOMPRESSION_ZLIB_PLUS 2
201	#define CHDCOMPRESSION_AV 3
202
203	/* A/V codec configuration parameters */
204	#define AV_CODEC_COMPRESS_CONFIG 1
205	#define AV_CODEC_DECOMPRESS_CONFIG 2
206
207	/* metadata parameters */
208	#define CHDMETATAG_WILDCARD 0
209	#define CHD_METAINDEX_APPEND ((UINT32)-1)
210
211	/* metadata flags */
212	#define CHD_MDFLAGS_CHECKSUM 0x01 /* indicates data is checksummed */
213
214	/* standard hard disk metadata */
215	#define HARD_DISK_METADATA_TAG 0x47444444 /* 'GDDD' */
216	#define HARD_DISK_METADATA_FORMAT "CYLS:%d,HEADS:%d,SECS:%d,BPS:%d"
217
218	/* hard disk identify information */
219	#define HARD_DISK_IDENT_METADATA_TAG 0x49444e54 /* 'IDNT' */
220
221	/* hard disk key information */
222	#define HARD_DISK_KEY_METADATA_TAG 0x4b455920 /* 'KEY ' */
223
224	/* pcmcia CIS information */
225	#define PCMCIA_CIS_METADATA_TAG 0x43495320 /* 'CIS ' */
226
227	/* standard CD-ROM metadata */
228	#define CDROM_OLD_METADATA_TAG 0x43484344 /* 'CHCD' */
229	#define CDROM_TRACK_METADATA_TAG 0x43485452 /* 'CHTR' */
230	#define CDROM_TRACK_METADATA_FORMAT "TRACK:%d TYPE:%s SUBTYPE:%s FRAMES:%d"
231	#define CDROM_TRACK_METADATA2_TAG 0x43485432 /* 'CHT2' */
232	#define CDROM_TRACK_METADATA2_FORMAT "TRACK:%d TYPE:%s SUBTYPE:%s FRAMES:%d PREGAP:%d PGTYPE:%s PGSUB:%s POSTGAP:%d"
233	#define GDROM_TRACK_METADATA_TAG 0x43484744 /* 'CHTD' */
234	#define GDROM_TRACK_METADATA_FORMAT "TRACK:%d TYPE:%s SUBTYPE:%s FRAMES:%d PAD:%d PREGAP:%d PGTYPE:%s PGSUB:%s POSTGAP:%d"
235
236	/* standard A/V metadata */
237	#define AV_METADATA_TAG 0x41564156 /* 'AVAV' */
238	#define AV_METADATA_FORMAT "FPS:%d.%06d WIDTH:%d HEIGHT:%d INTERLACED:%d CHANNELS:%d SAMPLERATE:%d"
239
240	/* A/V laserdisc frame metadata */
241	#define AV_LD_METADATA_TAG 0x41564C44 /* 'AVLD' */
242
243	/* CHD open values */
244	#define CHD_OPEN_READ 1
245	#define CHD_OPEN_READWRITE 2
246
247	/* error types */
248	enum _chd_error
249	{
250	CHDERR_NONE,
251	CHDERR_NO_INTERFACE,
252	CHDERR_OUT_OF_MEMORY,
253	CHDERR_INVALID_FILE,
254	CHDERR_INVALID_PARAMETER,
255	CHDERR_INVALID_DATA,
256	CHDERR_FILE_NOT_FOUND,
257	CHDERR_REQUIRES_PARENT,
258	CHDERR_FILE_NOT_WRITEABLE,
259	CHDERR_READ_ERROR,
260	CHDERR_WRITE_ERROR,
261	CHDERR_CODEC_ERROR,
262	CHDERR_INVALID_PARENT,
263	CHDERR_HUNK_OUT_OF_RANGE,
264	CHDERR_DECOMPRESSION_ERROR,
265	CHDERR_COMPRESSION_ERROR,
266	CHDERR_CANT_CREATE_FILE,
267	CHDERR_CANT_VERIFY,
268	CHDERR_NOT_SUPPORTED,
269	CHDERR_METADATA_NOT_FOUND,
270	CHDERR_INVALID_METADATA_SIZE,
271	CHDERR_UNSUPPORTED_VERSION,
272	CHDERR_VERIFY_INCOMPLETE,
273	CHDERR_INVALID_METADATA,
274	CHDERR_INVALID_STATE,
275	CHDERR_OPERATION_PENDING,
276	CHDERR_NO_ASYNC_OPERATION,
277	CHDERR_UNSUPPORTED_FORMAT
278	};
279	typedef enum _chd_error chd_error;
280
281
282
283	/***************************************************************************
284	TYPE DEFINITIONS
285	***************************************************************************/
286
287	/* opaque types */
288	typedef struct _chd_file chd_file;
289
290
291	/* extract header structure (NOT the on-disk header structure) */
292	typedef struct _chd_header chd_header;
293	struct _chd_header
294	{
295	UINT32 length; /* length of header data */
296	UINT32 version; /* drive format version */
297	UINT32 flags; /* flags field */
298	UINT32 compression[4]; /* compression type */
299	UINT32 hunkbytes; /* number of bytes per hunk */
300	UINT32 totalhunks; /* total # of hunks represented */
301	UINT64 logicalbytes; /* logical size of the data */
302	UINT64 metaoffset; /* offset in file of first metadata */
303	UINT64 mapoffset; /* TOOD V5 */
304	UINT8 md5[CHD_MD5_BYTES]; /* overall MD5 checksum */
305	UINT8 parentmd5[CHD_MD5_BYTES]; /* overall MD5 checksum of parent */
306	UINT8 sha1[CHD_SHA1_BYTES]; /* overall SHA1 checksum */
307	UINT8 rawsha1[CHD_SHA1_BYTES]; /* SHA1 checksum of raw data */
308	UINT8 parentsha1[CHD_SHA1_BYTES]; /* overall SHA1 checksum of parent */
309	UINT32 unitbytes; /* TODO V5 */
310	UINT64 unitcount; /* TODO V5 */
311	UINT32 hunkcount; /* TODO V5 */
312
313	// map information
314	UINT32 mapentrybytes; // length of each entry in a map (V5)
315	UINT8* rawmap; // raw map data
316
317	UINT32 obsolete_cylinders; /* obsolete field -- do not use! */
318	UINT32 obsolete_sectors; /* obsolete field -- do not use! */
319	UINT32 obsolete_heads; /* obsolete field -- do not use! */
320	UINT32 obsolete_hunksize; /* obsolete field -- do not use! */
321	};
322
323
324	/* structure for returning information about a verification pass */
325	typedef struct _chd_verify_result chd_verify_result;
326	struct _chd_verify_result
327	{
328	UINT8 md5[CHD_MD5_BYTES]; /* overall MD5 checksum */
329	UINT8 sha1[CHD_SHA1_BYTES]; /* overall SHA1 checksum */
330	UINT8 rawsha1[CHD_SHA1_BYTES]; /* SHA1 checksum of raw data */
331	UINT8 metasha1[CHD_SHA1_BYTES]; /* SHA1 checksum of metadata */
332	};
333
334
335
336	/***************************************************************************
337	FUNCTION PROTOTYPES
338	***************************************************************************/
339
340
341	/* ----- CHD file management ----- */
342
343	/* create a new CHD file fitting the given description */
344	// chd_error chd_create(const char filename, UINT64 logicalbytes, UINT32 hunkbytes, UINT32 compression, chd_file parent);
345
346	/* same as chd_create(), but accepts an already-opened core_file object */
347	// chd_error chd_create_file(core_file file, UINT64 logicalbytes, UINT32 hunkbytes, UINT32 compression, chd_file parent);
348
349	/* open an existing CHD file */
350	chd_error chd_open(const char filename, int mode, chd_file parent, chd_file **chd);
351
352	/* precache underlying file */
353	chd_error chd_precache(chd_file *chd);
354
355	/* close a CHD file */
356	void chd_close(chd_file *chd);
357
358	/* return the associated core_file */
359	core_file chd_core_file(chd_file chd);
360
361	/* return an error string for the given CHD error */
362	const char *chd_error_string(chd_error err);
363
364
365
366	/* ----- CHD header management ----- */
367
368	/* return a pointer to the extracted CHD header data */
369	const chd_header chd_get_header(chd_file chd);
370
371
372
373
374	/* ----- core data read/write ----- */
375
376	/* read one hunk from the CHD file */
377	chd_error chd_read(chd_file chd, UINT32 hunknum, void buffer);
378
379
380
381	/* ----- metadata management ----- */
382
383	/* get indexed metadata of a particular sort */
384	chd_error chd_get_metadata(chd_file chd, UINT32 searchtag, UINT32 searchindex, void output, UINT32 outputlen, UINT32 resultlen, UINT32 resulttag, UINT8 *resultflags);
385
386
387
388
389	/* ----- codec interfaces ----- */
390
391	/* set internal codec parameters */
392	chd_error chd_codec_config(chd_file chd, int param, void config);
393
394	/* return a string description of a codec */
395	const char *chd_get_codec_name(UINT32 codec);
396
397	#ifdef __cplusplus
398	}
399	#endif
400
401	#endif /* __CHD_H__ */