| 1 | /*************************************************************************** |
| 2 | |
| 3 | chd.c |
| 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 | #include <stddef.h> |
| 41 | #include <stdio.h> |
| 42 | #include <stdlib.h> |
| 43 | #include <string.h> |
| 44 | #include <time.h> |
| 45 | #include "chd.h" |
| 46 | #include "cdrom.h" |
| 47 | #include "flac.h" |
| 48 | #include "huffman.h" |
| 49 | #include "LzmaEnc.h" |
| 50 | #include "LzmaDec.h" |
| 51 | #include "md5.h" |
| 52 | #include "sha1.h" |
| 53 | #include "zlib.h" |
| 54 | |
| 55 | #define TRUE 1 |
| 56 | #define FALSE 0 |
| 57 | |
| 58 | #define MAX(x, y) (((x) > (y)) ? (x) : (y)) |
| 59 | #define MIN(x, y) (((x) < (y)) ? (x) : (y)) |
| 60 | |
| 61 | #define SHA1_DIGEST_SIZE 20 |
| 62 | |
| 63 | /*************************************************************************** |
| 64 | DEBUGGING |
| 65 | ***************************************************************************/ |
| 66 | |
| 67 | #define PRINTF_MAX_HUNK (0) |
| 68 | |
| 69 | /*************************************************************************** |
| 70 | CONSTANTS |
| 71 | ***************************************************************************/ |
| 72 | |
| 73 | #define MAP_STACK_ENTRIES 512 /* max number of entries to use on the stack */ |
| 74 | #define MAP_ENTRY_SIZE 16 /* V3 and later */ |
| 75 | #define OLD_MAP_ENTRY_SIZE 8 /* V1-V2 */ |
| 76 | #define METADATA_HEADER_SIZE 16 /* metadata header size */ |
| 77 | #define CRCMAP_HASH_SIZE 4095 /* number of CRC hashtable entries */ |
| 78 | |
| 79 | #define MAP_ENTRY_FLAG_TYPE_MASK 0x0f /* what type of hunk */ |
| 80 | #define MAP_ENTRY_FLAG_NO_CRC 0x10 /* no CRC is present */ |
| 81 | |
| 82 | #define CHD_V1_SECTOR_SIZE 512 /* size of a "sector" in the V1 header */ |
| 83 | |
| 84 | #define COOKIE_VALUE 0xbaadf00d |
| 85 | #define MAX_ZLIB_ALLOCS 64 |
| 86 | |
| 87 | #define END_OF_LIST_COOKIE "EndOfListCookie" |
| 88 | |
| 89 | #define NO_MATCH (~0) |
| 90 | |
| 91 | static const uint8_t s_cd_sync_header[12] = { 0x00,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0x00 }; |
| 92 | |
| 93 | /* V3-V4 entry types */ |
| 94 | enum |
| 95 | { |
| 96 | V34_MAP_ENTRY_TYPE_INVALID = 0, /* invalid type */ |
| 97 | V34_MAP_ENTRY_TYPE_COMPRESSED = 1, /* standard compression */ |
| 98 | V34_MAP_ENTRY_TYPE_UNCOMPRESSED = 2, /* uncompressed data */ |
| 99 | V34_MAP_ENTRY_TYPE_MINI = 3, /* mini: use offset as raw data */ |
| 100 | V34_MAP_ENTRY_TYPE_SELF_HUNK = 4, /* same as another hunk in this file */ |
| 101 | V34_MAP_ENTRY_TYPE_PARENT_HUNK = 5, /* same as a hunk in the parent file */ |
| 102 | V34_MAP_ENTRY_TYPE_2ND_COMPRESSED = 6 /* compressed with secondary algorithm (usually FLAC CDDA) */ |
| 103 | }; |
| 104 | |
| 105 | /* V5 compression types */ |
| 106 | enum |
| 107 | { |
| 108 | /* codec #0 |
| 109 | * these types are live when running */ |
| 110 | COMPRESSION_TYPE_0 = 0, |
| 111 | /* codec #1 */ |
| 112 | COMPRESSION_TYPE_1 = 1, |
| 113 | /* codec #2 */ |
| 114 | COMPRESSION_TYPE_2 = 2, |
| 115 | /* codec #3 */ |
| 116 | COMPRESSION_TYPE_3 = 3, |
| 117 | /* no compression; implicit length = hunkbytes */ |
| 118 | COMPRESSION_NONE = 4, |
| 119 | /* same as another block in this chd */ |
| 120 | COMPRESSION_SELF = 5, |
| 121 | /* same as a hunk's worth of units in the parent chd */ |
| 122 | COMPRESSION_PARENT = 6, |
| 123 | |
| 124 | /* start of small RLE run (4-bit length) |
| 125 | * these additional pseudo-types are used for compressed encodings: */ |
| 126 | COMPRESSION_RLE_SMALL, |
| 127 | /* start of large RLE run (8-bit length) */ |
| 128 | COMPRESSION_RLE_LARGE, |
| 129 | /* same as the last COMPRESSION_SELF block */ |
| 130 | COMPRESSION_SELF_0, |
| 131 | /* same as the last COMPRESSION_SELF block + 1 */ |
| 132 | COMPRESSION_SELF_1, |
| 133 | /* same block in the parent */ |
| 134 | COMPRESSION_PARENT_SELF, |
| 135 | /* same as the last COMPRESSION_PARENT block */ |
| 136 | COMPRESSION_PARENT_0, |
| 137 | /* same as the last COMPRESSION_PARENT block + 1 */ |
| 138 | COMPRESSION_PARENT_1 |
| 139 | }; |
| 140 | |
| 141 | /*************************************************************************** |
| 142 | MACROS |
| 143 | ***************************************************************************/ |
| 144 | |
| 145 | #define EARLY_EXIT(x) do { (void)(x); goto cleanup; } while (0) |
| 146 | |
| 147 | /*************************************************************************** |
| 148 | TYPE DEFINITIONS |
| 149 | ***************************************************************************/ |
| 150 | |
| 151 | /* interface to a codec */ |
| 152 | typedef struct _codec_interface codec_interface; |
| 153 | struct _codec_interface |
| 154 | { |
| 155 | UINT32 compression; /* type of compression */ |
| 156 | const char *compname; /* name of the algorithm */ |
| 157 | UINT8 lossy; /* is this a lossy algorithm? */ |
| 158 | chd_error (*init)(void *codec, UINT32 hunkbytes); /* codec initialize */ |
| 159 | void (*free)(void *codec); /* codec free */ |
| 160 | chd_error (*decompress)(void *codec, const uint8_t *src, uint32_t complen, uint8_t *dest, uint32_t destlen); /* decompress data */ |
| 161 | chd_error (*config)(void *codec, int param, void *config); /* configure */ |
| 162 | }; |
| 163 | |
| 164 | /* a single map entry */ |
| 165 | typedef struct _map_entry map_entry; |
| 166 | struct _map_entry |
| 167 | { |
| 168 | UINT64 offset; /* offset within the file of the data */ |
| 169 | UINT32 crc; /* 32-bit CRC of the data */ |
| 170 | UINT32 length; /* length of the data */ |
| 171 | UINT8 flags; /* misc flags */ |
| 172 | }; |
| 173 | |
| 174 | /* simple linked-list of hunks used for our CRC map */ |
| 175 | typedef struct _crcmap_entry crcmap_entry; |
| 176 | struct _crcmap_entry |
| 177 | { |
| 178 | UINT32 hunknum; /* hunk number */ |
| 179 | crcmap_entry * next; /* next entry in list */ |
| 180 | }; |
| 181 | |
| 182 | /* a single metadata entry */ |
| 183 | typedef struct _metadata_entry metadata_entry; |
| 184 | struct _metadata_entry |
| 185 | { |
| 186 | UINT64 offset; /* offset within the file of the header */ |
| 187 | UINT64 next; /* offset within the file of the next header */ |
| 188 | UINT64 prev; /* offset within the file of the previous header */ |
| 189 | UINT32 length; /* length of the metadata */ |
| 190 | UINT32 metatag; /* metadata tag */ |
| 191 | UINT8 flags; /* flag bits */ |
| 192 | }; |
| 193 | |
| 194 | /* codec-private data for the ZLIB codec */ |
| 195 | |
| 196 | typedef struct _zlib_allocator zlib_allocator; |
| 197 | struct _zlib_allocator |
| 198 | { |
| 199 | UINT32 * allocptr[MAX_ZLIB_ALLOCS]; |
| 200 | }; |
| 201 | |
| 202 | typedef struct _zlib_codec_data zlib_codec_data; |
| 203 | struct _zlib_codec_data |
| 204 | { |
| 205 | z_stream inflater; |
| 206 | zlib_allocator allocator; |
| 207 | }; |
| 208 | |
| 209 | /* codec-private data for the LZMA codec */ |
| 210 | #define MAX_LZMA_ALLOCS 64 |
| 211 | |
| 212 | typedef struct _lzma_allocator lzma_allocator; |
| 213 | struct _lzma_allocator |
| 214 | { |
| 215 | void *(*Alloc)(void *p, size_t size); |
| 216 | void (*Free)(void *p, void *address); /* address can be 0 */ |
| 217 | void (*FreeSz)(void *p, void *address, size_t size); /* address can be 0 */ |
| 218 | uint32_t* allocptr[MAX_LZMA_ALLOCS]; |
| 219 | }; |
| 220 | |
| 221 | typedef struct _lzma_codec_data lzma_codec_data; |
| 222 | struct _lzma_codec_data |
| 223 | { |
| 224 | CLzmaDec decoder; |
| 225 | lzma_allocator allocator; |
| 226 | }; |
| 227 | |
| 228 | /* codec-private data for the CDZL codec */ |
| 229 | typedef struct _cdzl_codec_data cdzl_codec_data; |
| 230 | struct _cdzl_codec_data { |
| 231 | /* internal state */ |
| 232 | zlib_codec_data base_decompressor; |
| 233 | zlib_codec_data subcode_decompressor; |
| 234 | uint8_t* buffer; |
| 235 | }; |
| 236 | |
| 237 | /* codec-private data for the CDLZ codec */ |
| 238 | typedef struct _cdlz_codec_data cdlz_codec_data; |
| 239 | struct _cdlz_codec_data { |
| 240 | /* internal state */ |
| 241 | lzma_codec_data base_decompressor; |
| 242 | zlib_codec_data subcode_decompressor; |
| 243 | uint8_t* buffer; |
| 244 | }; |
| 245 | |
| 246 | /* codec-private data for the CDFL codec */ |
| 247 | typedef struct _cdfl_codec_data cdfl_codec_data; |
| 248 | struct _cdfl_codec_data { |
| 249 | /* internal state */ |
| 250 | int swap_endian; |
| 251 | flac_decoder decoder; |
| 252 | z_stream inflater; |
| 253 | zlib_allocator allocator; |
| 254 | uint8_t* buffer; |
| 255 | }; |
| 256 | |
| 257 | /* internal representation of an open CHD file */ |
| 258 | struct _chd_file |
| 259 | { |
| 260 | UINT32 cookie; /* cookie, should equal COOKIE_VALUE */ |
| 261 | |
| 262 | core_file * file; /* handle to the open core file */ |
| 263 | UINT8 owns_file; /* flag indicating if this file should be closed on chd_close() */ |
| 264 | chd_header header; /* header, extracted from file */ |
| 265 | |
| 266 | chd_file * parent; /* pointer to parent file, or NULL */ |
| 267 | |
| 268 | map_entry * map; /* array of map entries */ |
| 269 | |
| 270 | UINT8 * cache; /* hunk cache pointer */ |
| 271 | UINT32 cachehunk; /* index of currently cached hunk */ |
| 272 | |
| 273 | UINT8 * compare; /* hunk compare pointer */ |
| 274 | UINT32 comparehunk; /* index of current compare data */ |
| 275 | |
| 276 | UINT8 * compressed; /* pointer to buffer for compressed data */ |
| 277 | const codec_interface * codecintf[4]; /* interface to the codec */ |
| 278 | |
| 279 | zlib_codec_data zlib_codec_data; /* zlib codec data */ |
| 280 | cdzl_codec_data cdzl_codec_data; /* cdzl codec data */ |
| 281 | cdlz_codec_data cdlz_codec_data; /* cdlz codec data */ |
| 282 | cdfl_codec_data cdfl_codec_data; /* cdfl codec data */ |
| 283 | |
| 284 | crcmap_entry * crcmap; /* CRC map entries */ |
| 285 | crcmap_entry * crcfree; /* free list CRC entries */ |
| 286 | crcmap_entry ** crctable; /* table of CRC entries */ |
| 287 | |
| 288 | UINT32 maxhunk; /* maximum hunk accessed */ |
| 289 | |
| 290 | UINT8 compressing; /* are we compressing? */ |
| 291 | MD5_CTX compmd5; /* running MD5 during compression */ |
| 292 | SHA1_CTX compsha1; /* running SHA1 during compression */ |
| 293 | UINT32 comphunk; /* next hunk we will compress */ |
| 294 | |
| 295 | UINT8 verifying; /* are we verifying? */ |
| 296 | MD5_CTX vermd5; /* running MD5 during verification */ |
| 297 | SHA1_CTX versha1; /* running SHA1 during verification */ |
| 298 | UINT32 verhunk; /* next hunk we will verify */ |
| 299 | |
| 300 | UINT32 async_hunknum; /* hunk index for asynchronous operations */ |
| 301 | void * async_buffer; /* buffer pointer for asynchronous operations */ |
| 302 | |
| 303 | UINT8 * file_cache; /* cache of underlying file */ |
| 304 | }; |
| 305 | |
| 306 | /* a single metadata hash entry */ |
| 307 | typedef struct _metadata_hash metadata_hash; |
| 308 | struct _metadata_hash |
| 309 | { |
| 310 | UINT8 tag[4]; /* tag of the metadata in big-endian */ |
| 311 | UINT8 sha1[CHD_SHA1_BYTES]; /* hash */ |
| 312 | }; |
| 313 | |
| 314 | /*************************************************************************** |
| 315 | GLOBAL VARIABLES |
| 316 | ***************************************************************************/ |
| 317 | |
| 318 | static const UINT8 nullmd5[CHD_MD5_BYTES] = { 0 }; |
| 319 | static const UINT8 nullsha1[CHD_SHA1_BYTES] = { 0 }; |
| 320 | |
| 321 | /*************************************************************************** |
| 322 | PROTOTYPES |
| 323 | ***************************************************************************/ |
| 324 | |
| 325 | /* internal header operations */ |
| 326 | static chd_error header_validate(const chd_header *header); |
| 327 | static chd_error header_read(chd_file *chd, chd_header *header); |
| 328 | |
| 329 | /* internal hunk read/write */ |
| 330 | static chd_error hunk_read_into_cache(chd_file *chd, UINT32 hunknum); |
| 331 | static chd_error hunk_read_into_memory(chd_file *chd, UINT32 hunknum, UINT8 *dest); |
| 332 | |
| 333 | /* internal map access */ |
| 334 | static chd_error map_read(chd_file *chd); |
| 335 | |
| 336 | /* metadata management */ |
| 337 | static chd_error metadata_find_entry(chd_file *chd, UINT32 metatag, UINT32 metaindex, metadata_entry *metaentry); |
| 338 | |
| 339 | /* zlib compression codec */ |
| 340 | static chd_error zlib_codec_init(void *codec, uint32_t hunkbytes); |
| 341 | static void zlib_codec_free(void *codec); |
| 342 | static chd_error zlib_codec_decompress(void *codec, const uint8_t *src, uint32_t complen, uint8_t *dest, uint32_t destlen); |
| 343 | static voidpf zlib_fast_alloc(voidpf opaque, uInt items, uInt size); |
| 344 | static void zlib_fast_free(voidpf opaque, voidpf address); |
| 345 | |
| 346 | /* lzma compression codec */ |
| 347 | static chd_error lzma_codec_init(void *codec, uint32_t hunkbytes); |
| 348 | static void lzma_codec_free(void *codec); |
| 349 | static chd_error lzma_codec_decompress(void *codec, const uint8_t *src, uint32_t complen, uint8_t *dest, uint32_t destlen); |
| 350 | |
| 351 | /* cdzl compression codec */ |
| 352 | static chd_error cdzl_codec_init(void* codec, uint32_t hunkbytes); |
| 353 | static void cdzl_codec_free(void* codec); |
| 354 | static chd_error cdzl_codec_decompress(void *codec, const uint8_t *src, uint32_t complen, uint8_t *dest, uint32_t destlen); |
| 355 | |
| 356 | /* cdlz compression codec */ |
| 357 | static chd_error cdlz_codec_init(void* codec, uint32_t hunkbytes); |
| 358 | static void cdlz_codec_free(void* codec); |
| 359 | static chd_error cdlz_codec_decompress(void *codec, const uint8_t *src, uint32_t complen, uint8_t *dest, uint32_t destlen); |
| 360 | |
| 361 | /* cdfl compression codec */ |
| 362 | static chd_error cdfl_codec_init(void* codec, uint32_t hunkbytes); |
| 363 | static void cdfl_codec_free(void* codec); |
| 364 | static chd_error cdfl_codec_decompress(void *codec, const uint8_t *src, uint32_t complen, uint8_t *dest, uint32_t destlen); |
| 365 | |
| 366 | /*************************************************************************** |
| 367 | * LZMA ALLOCATOR HELPER |
| 368 | *************************************************************************** |
| 369 | */ |
| 370 | |
| 371 | void *lzma_fast_alloc(void *p, size_t size); |
| 372 | void lzma_fast_free(void *p, void *address); |
| 373 | |
| 374 | /*------------------------------------------------- |
| 375 | * lzma_allocator_init |
| 376 | *------------------------------------------------- |
| 377 | */ |
| 378 | |
| 379 | void lzma_allocator_init(void* p) |
| 380 | { |
| 381 | lzma_allocator *codec = (lzma_allocator *)(p); |
| 382 | |
| 383 | /* reset pointer list */ |
| 384 | memset(codec->allocptr, 0, sizeof(codec->allocptr)); |
| 385 | codec->Alloc = lzma_fast_alloc; |
| 386 | codec->Free = lzma_fast_free; |
| 387 | } |
| 388 | |
| 389 | /*------------------------------------------------- |
| 390 | * lzma_allocator_free |
| 391 | *------------------------------------------------- |
| 392 | */ |
| 393 | |
| 394 | void lzma_allocator_free(void* p ) |
| 395 | { |
| 396 | lzma_allocator *codec = (lzma_allocator *)(p); |
| 397 | |
| 398 | /* free our memory */ |
| 399 | for (int i = 0 ; i < MAX_LZMA_ALLOCS ; i++) |
| 400 | { |
| 401 | if (codec->allocptr[i] != NULL) |
| 402 | free(codec->allocptr[i]); |
| 403 | } |
| 404 | } |
| 405 | |
| 406 | /*------------------------------------------------- |
| 407 | * lzma_fast_alloc - fast malloc for lzma, which |
| 408 | * allocates and frees memory frequently |
| 409 | *------------------------------------------------- |
| 410 | */ |
| 411 | |
| 412 | void *lzma_fast_alloc(void *p, size_t size) |
| 413 | { |
| 414 | lzma_allocator *codec = (lzma_allocator *)(p); |
| 415 | |
| 416 | /* compute the size, rounding to the nearest 1k */ |
| 417 | size = (size + 0x3ff) & ~0x3ff; |
| 418 | |
| 419 | /* reuse a hunk if we can */ |
| 420 | for (int scan = 0; scan < MAX_LZMA_ALLOCS; scan++) |
| 421 | { |
| 422 | uint32_t *ptr = codec->allocptr[scan]; |
| 423 | if (ptr != NULL && size == *ptr) |
| 424 | { |
| 425 | /* set the low bit of the size so we don't match next time */ |
| 426 | *ptr |= 1; |
| 427 | return ptr + 1; |
| 428 | } |
| 429 | } |
| 430 | |
| 431 | /* alloc a new one and put it into the list */ |
| 432 | uint32_t *addr = (uint32_t *)malloc(sizeof(uint8_t) * size + sizeof(uintptr_t)); |
| 433 | if (addr==NULL) |
| 434 | return NULL; |
| 435 | for (int scan = 0; scan < MAX_LZMA_ALLOCS; scan++) |
| 436 | { |
| 437 | if (codec->allocptr[scan] == NULL) |
| 438 | { |
| 439 | codec->allocptr[scan] = addr; |
| 440 | break; |
| 441 | } |
| 442 | } |
| 443 | |
| 444 | /* set the low bit of the size so we don't match next time */ |
| 445 | *addr = size | 1; |
| 446 | return addr + (sizeof(uint32_t) == sizeof(uintptr_t) ? 1 : 2); |
| 447 | } |
| 448 | |
| 449 | /*------------------------------------------------- |
| 450 | * lzma_fast_free - fast free for lzma, which |
| 451 | * allocates and frees memory frequently |
| 452 | *------------------------------------------------- |
| 453 | */ |
| 454 | |
| 455 | void lzma_fast_free(void *p, void *address) |
| 456 | { |
| 457 | if (address == NULL) |
| 458 | return; |
| 459 | |
| 460 | lzma_allocator *codec = (lzma_allocator *)(p); |
| 461 | |
| 462 | /* find the hunk */ |
| 463 | uint32_t *ptr = (uint32_t *)(address) - 1; |
| 464 | for (int scan = 0; scan < MAX_LZMA_ALLOCS; scan++) |
| 465 | { |
| 466 | if (ptr == codec->allocptr[scan]) |
| 467 | { |
| 468 | /* clear the low bit of the size to allow matches */ |
| 469 | *ptr &= ~1; |
| 470 | return; |
| 471 | } |
| 472 | } |
| 473 | } |
| 474 | |
| 475 | /*************************************************************************** |
| 476 | * LZMA DECOMPRESSOR |
| 477 | *************************************************************************** |
| 478 | */ |
| 479 | |
| 480 | /*------------------------------------------------- |
| 481 | * lzma_codec_init - constructor |
| 482 | *------------------------------------------------- |
| 483 | */ |
| 484 | |
| 485 | chd_error lzma_codec_init(void* codec, uint32_t hunkbytes) |
| 486 | { |
| 487 | lzma_codec_data* lzma_codec = (lzma_codec_data*) codec; |
| 488 | |
| 489 | /* construct the decoder */ |
| 490 | LzmaDec_Construct(&lzma_codec->decoder); |
| 491 | |
| 492 | /* FIXME: this code is written in a way that makes it impossible to safely upgrade the LZMA SDK |
| 493 | * This code assumes that the current version of the encoder imposes the same requirements on the |
| 494 | * decoder as the encoder used to produce the file. This is not necessarily true. The format |
| 495 | * needs to be changed so the encoder properties are written to the file. |
| 496 | |
| 497 | * configure the properties like the compressor did */ |
| 498 | CLzmaEncProps encoder_props; |
| 499 | LzmaEncProps_Init(&encoder_props); |
| 500 | encoder_props.level = 9; |
| 501 | encoder_props.reduceSize = hunkbytes; |
| 502 | LzmaEncProps_Normalize(&encoder_props); |
| 503 | |
| 504 | /* convert to decoder properties */ |
| 505 | lzma_allocator* alloc = &lzma_codec->allocator; |
| 506 | lzma_allocator_init(alloc); |
| 507 | CLzmaEncHandle enc = LzmaEnc_Create((ISzAlloc*)alloc); |
| 508 | if (!enc) |
| 509 | return CHDERR_DECOMPRESSION_ERROR; |
| 510 | if (LzmaEnc_SetProps(enc, &encoder_props) != SZ_OK) |
| 511 | { |
| 512 | LzmaEnc_Destroy(enc, (ISzAlloc*)&alloc, (ISzAlloc*)&alloc); |
| 513 | return CHDERR_DECOMPRESSION_ERROR; |
| 514 | } |
| 515 | Byte decoder_props[LZMA_PROPS_SIZE]; |
| 516 | SizeT props_size = sizeof(decoder_props); |
| 517 | if (LzmaEnc_WriteProperties(enc, decoder_props, &props_size) != SZ_OK) |
| 518 | { |
| 519 | LzmaEnc_Destroy(enc, (ISzAlloc*)alloc, (ISzAlloc*)alloc); |
| 520 | return CHDERR_DECOMPRESSION_ERROR; |
| 521 | } |
| 522 | LzmaEnc_Destroy(enc, (ISzAlloc*)alloc, (ISzAlloc*)alloc); |
| 523 | |
| 524 | /* do memory allocations */ |
| 525 | if (LzmaDec_Allocate(&lzma_codec->decoder, decoder_props, LZMA_PROPS_SIZE, (ISzAlloc*)alloc) != SZ_OK) |
| 526 | return CHDERR_DECOMPRESSION_ERROR; |
| 527 | |
| 528 | /* Okay */ |
| 529 | return CHDERR_NONE; |
| 530 | } |
| 531 | |
| 532 | /*------------------------------------------------- |
| 533 | * lzma_codec_free |
| 534 | *------------------------------------------------- |
| 535 | */ |
| 536 | |
| 537 | void lzma_codec_free(void* codec) |
| 538 | { |
| 539 | lzma_codec_data* lzma_codec = (lzma_codec_data*) codec; |
| 540 | |
| 541 | /* free memory */ |
| 542 | LzmaDec_Free(&lzma_codec->decoder, (ISzAlloc*)&lzma_codec->allocator); |
| 543 | lzma_allocator_free(&lzma_codec->allocator); |
| 544 | } |
| 545 | |
| 546 | /*------------------------------------------------- |
| 547 | * decompress - decompress data using the LZMA |
| 548 | * codec |
| 549 | *------------------------------------------------- |
| 550 | */ |
| 551 | |
| 552 | chd_error lzma_codec_decompress(void* codec, const uint8_t *src, uint32_t complen, uint8_t *dest, uint32_t destlen) |
| 553 | { |
| 554 | /* initialize */ |
| 555 | lzma_codec_data* lzma_codec = (lzma_codec_data*) codec; |
| 556 | LzmaDec_Init(&lzma_codec->decoder); |
| 557 | |
| 558 | /* decode */ |
| 559 | SizeT consumedlen = complen; |
| 560 | SizeT decodedlen = destlen; |
| 561 | ELzmaStatus status; |
| 562 | SRes res = LzmaDec_DecodeToBuf(&lzma_codec->decoder, dest, &decodedlen, src, &consumedlen, LZMA_FINISH_END, &status); |
| 563 | if ((res != SZ_OK && res != LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK) || consumedlen != complen || decodedlen != destlen) |
| 564 | return CHDERR_DECOMPRESSION_ERROR; |
| 565 | return CHDERR_NONE; |
| 566 | } |
| 567 | |
| 568 | /* cdlz */ |
| 569 | chd_error cdlz_codec_init(void* codec, uint32_t hunkbytes) |
| 570 | { |
| 571 | cdlz_codec_data* cdlz = (cdlz_codec_data*) codec; |
| 572 | |
| 573 | /* allocate buffer */ |
| 574 | cdlz->buffer = (uint8_t*)malloc(sizeof(uint8_t) * hunkbytes); |
| 575 | |
| 576 | /* make sure the CHD's hunk size is an even multiple of the frame size */ |
| 577 | lzma_codec_init(&cdlz->base_decompressor, (hunkbytes / CD_FRAME_SIZE) * CD_MAX_SECTOR_DATA); |
| 578 | zlib_codec_init(&cdlz->subcode_decompressor, (hunkbytes / CD_FRAME_SIZE) * CD_MAX_SUBCODE_DATA); |
| 579 | |
| 580 | if (hunkbytes % CD_FRAME_SIZE != 0) |
| 581 | return CHDERR_CODEC_ERROR; |
| 582 | |
| 583 | return CHDERR_NONE; |
| 584 | } |
| 585 | |
| 586 | void cdlz_codec_free(void* codec) |
| 587 | { |
| 588 | cdlz_codec_data* cdlz = (cdlz_codec_data*) codec; |
| 589 | free(cdlz->buffer); |
| 590 | lzma_codec_free(&cdlz->base_decompressor); |
| 591 | zlib_codec_free(&cdlz->subcode_decompressor); |
| 592 | } |
| 593 | |
| 594 | chd_error cdlz_codec_decompress(void *codec, const uint8_t *src, uint32_t complen, uint8_t *dest, uint32_t destlen) |
| 595 | { |
| 596 | uint8_t *sector; |
| 597 | cdlz_codec_data* cdlz = (cdlz_codec_data*)codec; |
| 598 | |
| 599 | /* determine header bytes */ |
| 600 | uint32_t frames = destlen / CD_FRAME_SIZE; |
| 601 | uint32_t complen_bytes = (destlen < 65536) ? 2 : 3; |
| 602 | uint32_t ecc_bytes = (frames + 7) / 8; |
| 603 | uint32_t header_bytes = ecc_bytes + complen_bytes; |
| 604 | |
| 605 | /* extract compressed length of base */ |
| 606 | uint32_t complen_base = (src[ecc_bytes + 0] << 8) | src[ecc_bytes + 1]; |
| 607 | if (complen_bytes > 2) |
| 608 | complen_base = (complen_base << 8) | src[ecc_bytes + 2]; |
| 609 | |
| 610 | /* reset and decode */ |
| 611 | lzma_codec_decompress(&cdlz->base_decompressor, &src[header_bytes], complen_base, &cdlz->buffer[0], frames * CD_MAX_SECTOR_DATA); |
| 612 | zlib_codec_decompress(&cdlz->subcode_decompressor, &src[header_bytes + complen_base], complen - complen_base - header_bytes, &cdlz->buffer[frames * CD_MAX_SECTOR_DATA], frames * CD_MAX_SUBCODE_DATA); |
| 613 | |
| 614 | /* reassemble the data */ |
| 615 | for (uint32_t framenum = 0; framenum < frames; framenum++) |
| 616 | { |
| 617 | memcpy(&dest[framenum * CD_FRAME_SIZE], &cdlz->buffer[framenum * CD_MAX_SECTOR_DATA], CD_MAX_SECTOR_DATA); |
| 618 | memcpy(&dest[framenum * CD_FRAME_SIZE + CD_MAX_SECTOR_DATA], &cdlz->buffer[frames * CD_MAX_SECTOR_DATA + framenum * CD_MAX_SUBCODE_DATA], CD_MAX_SUBCODE_DATA); |
| 619 | |
| 620 | /* reconstitute the ECC data and sync header */ |
| 621 | sector = (uint8_t *)&dest[framenum * CD_FRAME_SIZE]; |
| 622 | if ((src[framenum / 8] & (1 << (framenum % 8))) != 0) |
| 623 | { |
| 624 | memcpy(sector, s_cd_sync_header, sizeof(s_cd_sync_header)); |
| 625 | ecc_generate(sector); |
| 626 | } |
| 627 | } |
| 628 | return CHDERR_NONE; |
| 629 | } |
| 630 | |
| 631 | /* cdzl */ |
| 632 | |
| 633 | chd_error cdzl_codec_init(void *codec, uint32_t hunkbytes) |
| 634 | { |
| 635 | cdzl_codec_data* cdzl = (cdzl_codec_data*)codec; |
| 636 | |
| 637 | /* make sure the CHD's hunk size is an even multiple of the frame size */ |
| 638 | zlib_codec_init(&cdzl->base_decompressor, (hunkbytes / CD_FRAME_SIZE) * CD_MAX_SECTOR_DATA); |
| 639 | zlib_codec_init(&cdzl->subcode_decompressor, (hunkbytes / CD_FRAME_SIZE) * CD_MAX_SUBCODE_DATA); |
| 640 | |
| 641 | cdzl->buffer = (uint8_t*)malloc(sizeof(uint8_t) * hunkbytes); |
| 642 | if (hunkbytes % CD_FRAME_SIZE != 0) |
| 643 | return CHDERR_CODEC_ERROR; |
| 644 | |
| 645 | return CHDERR_NONE; |
| 646 | } |
| 647 | |
| 648 | void cdzl_codec_free(void *codec) |
| 649 | { |
| 650 | cdzl_codec_data* cdzl = (cdzl_codec_data*)codec; |
| 651 | zlib_codec_free(&cdzl->base_decompressor); |
| 652 | zlib_codec_free(&cdzl->subcode_decompressor); |
| 653 | free(cdzl->buffer); |
| 654 | } |
| 655 | |
| 656 | chd_error cdzl_codec_decompress(void *codec, const uint8_t *src, uint32_t complen, uint8_t *dest, uint32_t destlen) |
| 657 | { |
| 658 | uint8_t *sector; |
| 659 | cdzl_codec_data* cdzl = (cdzl_codec_data*)codec; |
| 660 | |
| 661 | /* determine header bytes */ |
| 662 | uint32_t frames = destlen / CD_FRAME_SIZE; |
| 663 | uint32_t complen_bytes = (destlen < 65536) ? 2 : 3; |
| 664 | uint32_t ecc_bytes = (frames + 7) / 8; |
| 665 | uint32_t header_bytes = ecc_bytes + complen_bytes; |
| 666 | |
| 667 | /* extract compressed length of base */ |
| 668 | uint32_t complen_base = (src[ecc_bytes + 0] << 8) | src[ecc_bytes + 1]; |
| 669 | if (complen_bytes > 2) |
| 670 | complen_base = (complen_base << 8) | src[ecc_bytes + 2]; |
| 671 | |
| 672 | /* reset and decode */ |
| 673 | zlib_codec_decompress(&cdzl->base_decompressor, &src[header_bytes], complen_base, &cdzl->buffer[0], frames * CD_MAX_SECTOR_DATA); |
| 674 | zlib_codec_decompress(&cdzl->subcode_decompressor, &src[header_bytes + complen_base], complen - complen_base - header_bytes, &cdzl->buffer[frames * CD_MAX_SECTOR_DATA], frames * CD_MAX_SUBCODE_DATA); |
| 675 | |
| 676 | /* reassemble the data */ |
| 677 | for (uint32_t framenum = 0; framenum < frames; framenum++) |
| 678 | { |
| 679 | memcpy(&dest[framenum * CD_FRAME_SIZE], &cdzl->buffer[framenum * CD_MAX_SECTOR_DATA], CD_MAX_SECTOR_DATA); |
| 680 | memcpy(&dest[framenum * CD_FRAME_SIZE + CD_MAX_SECTOR_DATA], &cdzl->buffer[frames * CD_MAX_SECTOR_DATA + framenum * CD_MAX_SUBCODE_DATA], CD_MAX_SUBCODE_DATA); |
| 681 | |
| 682 | /* reconstitute the ECC data and sync header */ |
| 683 | sector = (uint8_t *)&dest[framenum * CD_FRAME_SIZE]; |
| 684 | if ((src[framenum / 8] & (1 << (framenum % 8))) != 0) |
| 685 | { |
| 686 | memcpy(sector, s_cd_sync_header, sizeof(s_cd_sync_header)); |
| 687 | ecc_generate(sector); |
| 688 | } |
| 689 | } |
| 690 | return CHDERR_NONE; |
| 691 | } |
| 692 | |
| 693 | /*************************************************************************** |
| 694 | * CD FLAC DECOMPRESSOR |
| 695 | *************************************************************************** |
| 696 | */ |
| 697 | |
| 698 | /*------------------------------------------------------ |
| 699 | * cdfl_codec_blocksize - return the optimal block size |
| 700 | *------------------------------------------------------ |
| 701 | */ |
| 702 | |
| 703 | static uint32_t cdfl_codec_blocksize(uint32_t bytes) |
| 704 | { |
| 705 | /* determine FLAC block size, which must be 16-65535 |
| 706 | * clamp to 2k since that's supposed to be the sweet spot */ |
| 707 | uint32_t hunkbytes = bytes / 4; |
| 708 | while (hunkbytes > 2048) |
| 709 | hunkbytes /= 2; |
| 710 | return hunkbytes; |
| 711 | } |
| 712 | |
| 713 | chd_error cdfl_codec_init(void *codec, uint32_t hunkbytes) |
| 714 | { |
| 715 | cdfl_codec_data *cdfl = (cdfl_codec_data*)codec; |
| 716 | |
| 717 | cdfl->buffer = (uint8_t*)malloc(sizeof(uint8_t) * hunkbytes); |
| 718 | |
| 719 | /* make sure the CHD's hunk size is an even multiple of the frame size */ |
| 720 | if (hunkbytes % CD_FRAME_SIZE != 0) |
| 721 | return CHDERR_CODEC_ERROR; |
| 722 | |
| 723 | /* determine whether we want native or swapped samples */ |
| 724 | uint16_t native_endian = 0; |
| 725 | *(uint8_t *)(&native_endian) = 1; |
| 726 | cdfl->swap_endian = (native_endian & 1); |
| 727 | |
| 728 | /* init the inflater */ |
| 729 | cdfl->inflater.next_in = (Bytef *)cdfl; /* bogus, but that's ok */ |
| 730 | cdfl->inflater.avail_in = 0; |
| 731 | #if 0 |
| 732 | cdfl->allocator.install(cdfl->inflater); |
| 733 | #endif |
| 734 | cdfl->inflater.zalloc = zlib_fast_alloc; |
| 735 | cdfl->inflater.zfree = zlib_fast_free; |
| 736 | cdfl->inflater.opaque = &cdfl->allocator; |
| 737 | int zerr = inflateInit2(&cdfl->inflater, -MAX_WBITS); |
| 738 | |
| 739 | /* convert errors */ |
| 740 | if (zerr == Z_MEM_ERROR) |
| 741 | return CHDERR_OUT_OF_MEMORY; |
| 742 | else if (zerr != Z_OK) |
| 743 | return CHDERR_CODEC_ERROR; |
| 744 | |
| 745 | /* flac decoder init */ |
| 746 | flac_decoder_init(&cdfl->decoder); |
| 747 | return CHDERR_NONE; |
| 748 | } |
| 749 | |
| 750 | void cdfl_codec_free(void *codec) |
| 751 | { |
| 752 | cdfl_codec_data *cdfl = (cdfl_codec_data*)codec; |
| 753 | free(cdfl->buffer); |
| 754 | inflateEnd(&cdfl->inflater); |
| 755 | flac_decoder_free(&cdfl->decoder); |
| 756 | } |
| 757 | |
| 758 | chd_error cdfl_codec_decompress(void *codec, const uint8_t *src, uint32_t complen, uint8_t *dest, uint32_t destlen) |
| 759 | { |
| 760 | cdfl_codec_data *cdfl = (cdfl_codec_data*)codec; |
| 761 | |
| 762 | /* reset and decode */ |
| 763 | uint32_t frames = destlen / CD_FRAME_SIZE; |
| 764 | |
| 765 | if (!flac_decoder_reset(&cdfl->decoder, 44100, 2, cdfl_codec_blocksize(frames * CD_MAX_SECTOR_DATA), src, complen)) |
| 766 | return CHDERR_DECOMPRESSION_ERROR; |
| 767 | uint8_t *buffer = &cdfl->buffer[0]; |
| 768 | if (!flac_decoder_decode_interleaved(&cdfl->decoder, (int16_t *)(buffer), frames * CD_MAX_SECTOR_DATA/4, cdfl->swap_endian)) |
| 769 | return CHDERR_DECOMPRESSION_ERROR; |
| 770 | |
| 771 | /* inflate the subcode data */ |
| 772 | uint32_t offset = flac_decoder_finish(&cdfl->decoder); |
| 773 | cdfl->inflater.next_in = (Bytef *)(src + offset); |
| 774 | cdfl->inflater.avail_in = complen - offset; |
| 775 | cdfl->inflater.total_in = 0; |
| 776 | cdfl->inflater.next_out = &cdfl->buffer[frames * CD_MAX_SECTOR_DATA]; |
| 777 | cdfl->inflater.avail_out = frames * CD_MAX_SUBCODE_DATA; |
| 778 | cdfl->inflater.total_out = 0; |
| 779 | int zerr = inflateReset(&cdfl->inflater); |
| 780 | if (zerr != Z_OK) |
| 781 | return CHDERR_DECOMPRESSION_ERROR; |
| 782 | |
| 783 | /* do it */ |
| 784 | zerr = inflate(&cdfl->inflater, Z_FINISH); |
| 785 | if (zerr != Z_STREAM_END) |
| 786 | return CHDERR_DECOMPRESSION_ERROR; |
| 787 | if (cdfl->inflater.total_out != frames * CD_MAX_SUBCODE_DATA) |
| 788 | return CHDERR_DECOMPRESSION_ERROR; |
| 789 | |
| 790 | /* reassemble the data */ |
| 791 | for (uint32_t framenum = 0; framenum < frames; framenum++) |
| 792 | { |
| 793 | memcpy(&dest[framenum * CD_FRAME_SIZE], &cdfl->buffer[framenum * CD_MAX_SECTOR_DATA], CD_MAX_SECTOR_DATA); |
| 794 | memcpy(&dest[framenum * CD_FRAME_SIZE + CD_MAX_SECTOR_DATA], &cdfl->buffer[frames * CD_MAX_SECTOR_DATA + framenum * CD_MAX_SUBCODE_DATA], CD_MAX_SUBCODE_DATA); |
| 795 | } |
| 796 | |
| 797 | return CHDERR_NONE; |
| 798 | } |
| 799 | /*************************************************************************** |
| 800 | CODEC INTERFACES |
| 801 | ***************************************************************************/ |
| 802 | |
| 803 | static const codec_interface codec_interfaces[] = |
| 804 | { |
| 805 | /* "none" or no compression */ |
| 806 | { |
| 807 | CHDCOMPRESSION_NONE, |
| 808 | "none", |
| 809 | FALSE, |
| 810 | NULL, |
| 811 | NULL, |
| 812 | NULL, |
| 813 | NULL |
| 814 | }, |
| 815 | |
| 816 | /* standard zlib compression */ |
| 817 | { |
| 818 | CHDCOMPRESSION_ZLIB, |
| 819 | "zlib", |
| 820 | FALSE, |
| 821 | zlib_codec_init, |
| 822 | zlib_codec_free, |
| 823 | zlib_codec_decompress, |
| 824 | NULL |
| 825 | }, |
| 826 | |
| 827 | /* zlib+ compression */ |
| 828 | { |
| 829 | CHDCOMPRESSION_ZLIB_PLUS, |
| 830 | "zlib+", |
| 831 | FALSE, |
| 832 | zlib_codec_init, |
| 833 | zlib_codec_free, |
| 834 | zlib_codec_decompress, |
| 835 | NULL |
| 836 | }, |
| 837 | |
| 838 | /* V5 zlib compression */ |
| 839 | { |
| 840 | CHD_CODEC_ZLIB, |
| 841 | "zlib (Deflate)", |
| 842 | FALSE, |
| 843 | zlib_codec_init, |
| 844 | zlib_codec_free, |
| 845 | zlib_codec_decompress, |
| 846 | NULL |
| 847 | }, |
| 848 | |
| 849 | /* V5 CD zlib compression */ |
| 850 | { |
| 851 | CHD_CODEC_CD_ZLIB, |
| 852 | "cdzl (CD Deflate)", |
| 853 | FALSE, |
| 854 | cdzl_codec_init, |
| 855 | cdzl_codec_free, |
| 856 | cdzl_codec_decompress, |
| 857 | NULL |
| 858 | }, |
| 859 | |
| 860 | /* V5 CD lzma compression */ |
| 861 | { |
| 862 | CHD_CODEC_CD_LZMA, |
| 863 | "cdlz (CD LZMA)", |
| 864 | FALSE, |
| 865 | cdlz_codec_init, |
| 866 | cdlz_codec_free, |
| 867 | cdlz_codec_decompress, |
| 868 | NULL |
| 869 | }, |
| 870 | |
| 871 | /* V5 CD flac compression */ |
| 872 | { |
| 873 | CHD_CODEC_CD_FLAC, |
| 874 | "cdfl (CD FLAC)", |
| 875 | FALSE, |
| 876 | cdfl_codec_init, |
| 877 | cdfl_codec_free, |
| 878 | cdfl_codec_decompress, |
| 879 | NULL |
| 880 | }, |
| 881 | }; |
| 882 | |
| 883 | /*************************************************************************** |
| 884 | INLINE FUNCTIONS |
| 885 | ***************************************************************************/ |
| 886 | |
| 887 | /*------------------------------------------------- |
| 888 | get_bigendian_uint64 - fetch a UINT64 from |
| 889 | the data stream in bigendian order |
| 890 | -------------------------------------------------*/ |
| 891 | |
| 892 | static inline UINT64 get_bigendian_uint64(const UINT8 *base) |
| 893 | { |
| 894 | return ((UINT64)base[0] << 56) | ((UINT64)base[1] << 48) | ((UINT64)base[2] << 40) | ((UINT64)base[3] << 32) | |
| 895 | ((UINT64)base[4] << 24) | ((UINT64)base[5] << 16) | ((UINT64)base[6] << 8) | (UINT64)base[7]; |
| 896 | } |
| 897 | |
| 898 | /*------------------------------------------------- |
| 899 | put_bigendian_uint64 - write a UINT64 to |
| 900 | the data stream in bigendian order |
| 901 | -------------------------------------------------*/ |
| 902 | |
| 903 | static inline void put_bigendian_uint64(UINT8 *base, UINT64 value) |
| 904 | { |
| 905 | base[0] = value >> 56; |
| 906 | base[1] = value >> 48; |
| 907 | base[2] = value >> 40; |
| 908 | base[3] = value >> 32; |
| 909 | base[4] = value >> 24; |
| 910 | base[5] = value >> 16; |
| 911 | base[6] = value >> 8; |
| 912 | base[7] = value; |
| 913 | } |
| 914 | |
| 915 | /*------------------------------------------------- |
| 916 | get_bigendian_uint48 - fetch a UINT48 from |
| 917 | the data stream in bigendian order |
| 918 | -------------------------------------------------*/ |
| 919 | |
| 920 | static inline UINT64 get_bigendian_uint48(const UINT8 *base) |
| 921 | { |
| 922 | return ((UINT64)base[0] << 40) | ((UINT64)base[1] << 32) | |
| 923 | ((UINT64)base[2] << 24) | ((UINT64)base[3] << 16) | ((UINT64)base[4] << 8) | (UINT64)base[5]; |
| 924 | } |
| 925 | |
| 926 | /*------------------------------------------------- |
| 927 | put_bigendian_uint48 - write a UINT48 to |
| 928 | the data stream in bigendian order |
| 929 | -------------------------------------------------*/ |
| 930 | |
| 931 | static inline void put_bigendian_uint48(UINT8 *base, UINT64 value) |
| 932 | { |
| 933 | value &= 0xffffffffffff; |
| 934 | base[0] = value >> 40; |
| 935 | base[1] = value >> 32; |
| 936 | base[2] = value >> 24; |
| 937 | base[3] = value >> 16; |
| 938 | base[4] = value >> 8; |
| 939 | base[5] = value; |
| 940 | } |
| 941 | /*------------------------------------------------- |
| 942 | get_bigendian_uint32 - fetch a UINT32 from |
| 943 | the data stream in bigendian order |
| 944 | -------------------------------------------------*/ |
| 945 | |
| 946 | static inline UINT32 get_bigendian_uint32(const UINT8 *base) |
| 947 | { |
| 948 | return (base[0] << 24) | (base[1] << 16) | (base[2] << 8) | base[3]; |
| 949 | } |
| 950 | |
| 951 | /*------------------------------------------------- |
| 952 | put_bigendian_uint32 - write a UINT32 to |
| 953 | the data stream in bigendian order |
| 954 | -------------------------------------------------*/ |
| 955 | |
| 956 | static inline void put_bigendian_uint32(UINT8 *base, UINT32 value) |
| 957 | { |
| 958 | base[0] = value >> 24; |
| 959 | base[1] = value >> 16; |
| 960 | base[2] = value >> 8; |
| 961 | base[3] = value; |
| 962 | } |
| 963 | |
| 964 | /*------------------------------------------------- |
| 965 | put_bigendian_uint24 - write a UINT24 to |
| 966 | the data stream in bigendian order |
| 967 | -------------------------------------------------*/ |
| 968 | |
| 969 | static inline void put_bigendian_uint24(UINT8 *base, UINT32 value) |
| 970 | { |
| 971 | value &= 0xffffff; |
| 972 | base[0] = value >> 16; |
| 973 | base[1] = value >> 8; |
| 974 | base[2] = value; |
| 975 | } |
| 976 | |
| 977 | /*------------------------------------------------- |
| 978 | get_bigendian_uint24 - fetch a UINT24 from |
| 979 | the data stream in bigendian order |
| 980 | -------------------------------------------------*/ |
| 981 | |
| 982 | static inline UINT32 get_bigendian_uint24(const UINT8 *base) |
| 983 | { |
| 984 | return (base[0] << 16) | (base[1] << 8) | base[2]; |
| 985 | } |
| 986 | |
| 987 | /*------------------------------------------------- |
| 988 | get_bigendian_uint16 - fetch a UINT16 from |
| 989 | the data stream in bigendian order |
| 990 | -------------------------------------------------*/ |
| 991 | |
| 992 | static inline UINT16 get_bigendian_uint16(const UINT8 *base) |
| 993 | { |
| 994 | return (base[0] << 8) | base[1]; |
| 995 | } |
| 996 | |
| 997 | /*------------------------------------------------- |
| 998 | put_bigendian_uint16 - write a UINT16 to |
| 999 | the data stream in bigendian order |
| 1000 | -------------------------------------------------*/ |
| 1001 | |
| 1002 | static inline void put_bigendian_uint16(UINT8 *base, UINT16 value) |
| 1003 | { |
| 1004 | base[0] = value >> 8; |
| 1005 | base[1] = value; |
| 1006 | } |
| 1007 | |
| 1008 | /*------------------------------------------------- |
| 1009 | map_extract - extract a single map |
| 1010 | entry from the datastream |
| 1011 | -------------------------------------------------*/ |
| 1012 | |
| 1013 | static inline void map_extract(const UINT8 *base, map_entry *entry) |
| 1014 | { |
| 1015 | entry->offset = get_bigendian_uint64(&base[0]); |
| 1016 | entry->crc = get_bigendian_uint32(&base[8]); |
| 1017 | entry->length = get_bigendian_uint16(&base[12]) | (base[14] << 16); |
| 1018 | entry->flags = base[15]; |
| 1019 | } |
| 1020 | |
| 1021 | /*------------------------------------------------- |
| 1022 | map_assemble - write a single map |
| 1023 | entry to the datastream |
| 1024 | -------------------------------------------------*/ |
| 1025 | |
| 1026 | static inline void map_assemble(UINT8 *base, map_entry *entry) |
| 1027 | { |
| 1028 | put_bigendian_uint64(&base[0], entry->offset); |
| 1029 | put_bigendian_uint32(&base[8], entry->crc); |
| 1030 | put_bigendian_uint16(&base[12], entry->length); |
| 1031 | base[14] = entry->length >> 16; |
| 1032 | base[15] = entry->flags; |
| 1033 | } |
| 1034 | |
| 1035 | /*------------------------------------------------- |
| 1036 | map_size_v5 - calculate CHDv5 map size |
| 1037 | -------------------------------------------------*/ |
| 1038 | static inline int map_size_v5(chd_header* header) |
| 1039 | { |
| 1040 | return header->hunkcount * header->mapentrybytes; |
| 1041 | } |
| 1042 | |
| 1043 | /*------------------------------------------------- |
| 1044 | crc16 - calculate CRC16 (from hashing.cpp) |
| 1045 | -------------------------------------------------*/ |
| 1046 | uint16_t crc16(const void *data, uint32_t length) |
| 1047 | { |
| 1048 | uint16_t crc = 0xffff; |
| 1049 | |
| 1050 | static const uint16_t s_table[256] = |
| 1051 | { |
| 1052 | 0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50a5, 0x60c6, 0x70e7, |
| 1053 | 0x8108, 0x9129, 0xa14a, 0xb16b, 0xc18c, 0xd1ad, 0xe1ce, 0xf1ef, |
| 1054 | 0x1231, 0x0210, 0x3273, 0x2252, 0x52b5, 0x4294, 0x72f7, 0x62d6, |
| 1055 | 0x9339, 0x8318, 0xb37b, 0xa35a, 0xd3bd, 0xc39c, 0xf3ff, 0xe3de, |
| 1056 | 0x2462, 0x3443, 0x0420, 0x1401, 0x64e6, 0x74c7, 0x44a4, 0x5485, |
| 1057 | 0xa56a, 0xb54b, 0x8528, 0x9509, 0xe5ee, 0xf5cf, 0xc5ac, 0xd58d, |
| 1058 | 0x3653, 0x2672, 0x1611, 0x0630, 0x76d7, 0x66f6, 0x5695, 0x46b4, |
| 1059 | 0xb75b, 0xa77a, 0x9719, 0x8738, 0xf7df, 0xe7fe, 0xd79d, 0xc7bc, |
| 1060 | 0x48c4, 0x58e5, 0x6886, 0x78a7, 0x0840, 0x1861, 0x2802, 0x3823, |
| 1061 | 0xc9cc, 0xd9ed, 0xe98e, 0xf9af, 0x8948, 0x9969, 0xa90a, 0xb92b, |
| 1062 | 0x5af5, 0x4ad4, 0x7ab7, 0x6a96, 0x1a71, 0x0a50, 0x3a33, 0x2a12, |
| 1063 | 0xdbfd, 0xcbdc, 0xfbbf, 0xeb9e, 0x9b79, 0x8b58, 0xbb3b, 0xab1a, |
| 1064 | 0x6ca6, 0x7c87, 0x4ce4, 0x5cc5, 0x2c22, 0x3c03, 0x0c60, 0x1c41, |
| 1065 | 0xedae, 0xfd8f, 0xcdec, 0xddcd, 0xad2a, 0xbd0b, 0x8d68, 0x9d49, |
| 1066 | 0x7e97, 0x6eb6, 0x5ed5, 0x4ef4, 0x3e13, 0x2e32, 0x1e51, 0x0e70, |
| 1067 | 0xff9f, 0xefbe, 0xdfdd, 0xcffc, 0xbf1b, 0xaf3a, 0x9f59, 0x8f78, |
| 1068 | 0x9188, 0x81a9, 0xb1ca, 0xa1eb, 0xd10c, 0xc12d, 0xf14e, 0xe16f, |
| 1069 | 0x1080, 0x00a1, 0x30c2, 0x20e3, 0x5004, 0x4025, 0x7046, 0x6067, |
| 1070 | 0x83b9, 0x9398, 0xa3fb, 0xb3da, 0xc33d, 0xd31c, 0xe37f, 0xf35e, |
| 1071 | 0x02b1, 0x1290, 0x22f3, 0x32d2, 0x4235, 0x5214, 0x6277, 0x7256, |
| 1072 | 0xb5ea, 0xa5cb, 0x95a8, 0x8589, 0xf56e, 0xe54f, 0xd52c, 0xc50d, |
| 1073 | 0x34e2, 0x24c3, 0x14a0, 0x0481, 0x7466, 0x6447, 0x5424, 0x4405, |
| 1074 | 0xa7db, 0xb7fa, 0x8799, 0x97b8, 0xe75f, 0xf77e, 0xc71d, 0xd73c, |
| 1075 | 0x26d3, 0x36f2, 0x0691, 0x16b0, 0x6657, 0x7676, 0x4615, 0x5634, |
| 1076 | 0xd94c, 0xc96d, 0xf90e, 0xe92f, 0x99c8, 0x89e9, 0xb98a, 0xa9ab, |
| 1077 | 0x5844, 0x4865, 0x7806, 0x6827, 0x18c0, 0x08e1, 0x3882, 0x28a3, |
| 1078 | 0xcb7d, 0xdb5c, 0xeb3f, 0xfb1e, 0x8bf9, 0x9bd8, 0xabbb, 0xbb9a, |
| 1079 | 0x4a75, 0x5a54, 0x6a37, 0x7a16, 0x0af1, 0x1ad0, 0x2ab3, 0x3a92, |
| 1080 | 0xfd2e, 0xed0f, 0xdd6c, 0xcd4d, 0xbdaa, 0xad8b, 0x9de8, 0x8dc9, |
| 1081 | 0x7c26, 0x6c07, 0x5c64, 0x4c45, 0x3ca2, 0x2c83, 0x1ce0, 0x0cc1, |
| 1082 | 0xef1f, 0xff3e, 0xcf5d, 0xdf7c, 0xaf9b, 0xbfba, 0x8fd9, 0x9ff8, |
| 1083 | 0x6e17, 0x7e36, 0x4e55, 0x5e74, 0x2e93, 0x3eb2, 0x0ed1, 0x1ef0 |
| 1084 | }; |
| 1085 | |
| 1086 | const uint8_t *src = (uint8_t*)data; |
| 1087 | |
| 1088 | /* fetch the current value into a local and rip through the source data */ |
| 1089 | while (length-- != 0) |
| 1090 | crc = (crc << 8) ^ s_table[(crc >> 8) ^ *src++]; |
| 1091 | return crc; |
| 1092 | } |
| 1093 | |
| 1094 | /*------------------------------------------------- |
| 1095 | compressed - test if CHD file is compressed |
| 1096 | +-------------------------------------------------*/ |
| 1097 | |
| 1098 | static inline int compressed(chd_header* header) { |
| 1099 | return header->compression[0] != CHD_CODEC_NONE; |
| 1100 | } |
| 1101 | |
| 1102 | /*------------------------------------------------- |
| 1103 | decompress_v5_map - decompress the v5 map |
| 1104 | -------------------------------------------------*/ |
| 1105 | |
| 1106 | static chd_error decompress_v5_map(chd_file* chd, chd_header* header) |
| 1107 | { |
| 1108 | int rawmapsize = map_size_v5(header); |
| 1109 | |
| 1110 | if (!compressed(header)) |
| 1111 | { |
| 1112 | header->rawmap = (uint8_t*)malloc(rawmapsize); |
| 1113 | core_fseek(chd->file, header->mapoffset, SEEK_SET); |
| 1114 | core_fread(chd->file, header->rawmap, rawmapsize); |
| 1115 | return CHDERR_NONE; |
| 1116 | } |
| 1117 | |
| 1118 | /* read the reader */ |
| 1119 | uint8_t rawbuf[16]; |
| 1120 | core_fseek(chd->file, header->mapoffset, SEEK_SET); |
| 1121 | core_fread(chd->file, rawbuf, sizeof(rawbuf)); |
| 1122 | uint32_t const mapbytes = get_bigendian_uint32(&rawbuf[0]); |
| 1123 | uint64_t const firstoffs = get_bigendian_uint48(&rawbuf[4]); |
| 1124 | uint16_t const mapcrc = get_bigendian_uint16(&rawbuf[10]); |
| 1125 | uint8_t const lengthbits = rawbuf[12]; |
| 1126 | uint8_t const selfbits = rawbuf[13]; |
| 1127 | uint8_t const parentbits = rawbuf[14]; |
| 1128 | |
| 1129 | /* now read the map */ |
| 1130 | uint8_t* compressed = (uint8_t*)malloc(sizeof(uint8_t) * mapbytes); |
| 1131 | core_fseek(chd->file, header->mapoffset + 16, SEEK_SET); |
| 1132 | core_fread(chd->file, compressed, mapbytes); |
| 1133 | struct bitstream* bitbuf = create_bitstream(compressed, sizeof(uint8_t) * mapbytes); |
| 1134 | header->rawmap = (uint8_t*)malloc(rawmapsize); |
| 1135 | |
| 1136 | /* first decode the compression types */ |
| 1137 | struct huffman_decoder* decoder = create_huffman_decoder(16, 8); |
| 1138 | enum huffman_error err = huffman_import_tree_rle(decoder, bitbuf); |
| 1139 | if (err != HUFFERR_NONE) |
| 1140 | return CHDERR_DECOMPRESSION_ERROR; |
| 1141 | uint8_t lastcomp = 0; |
| 1142 | int repcount = 0; |
| 1143 | for (int hunknum = 0; hunknum < header->hunkcount; hunknum++) |
| 1144 | { |
| 1145 | uint8_t *rawmap = header->rawmap + (hunknum * 12); |
| 1146 | if (repcount > 0) |
| 1147 | rawmap[0] = lastcomp, repcount--; |
| 1148 | else |
| 1149 | { |
| 1150 | uint8_t val = huffman_decode_one(decoder, bitbuf); |
| 1151 | if (val == COMPRESSION_RLE_SMALL) |
| 1152 | rawmap[0] = lastcomp, repcount = 2 + huffman_decode_one(decoder, bitbuf); |
| 1153 | else if (val == COMPRESSION_RLE_LARGE) |
| 1154 | rawmap[0] = lastcomp, repcount = 2 + 16 + (huffman_decode_one(decoder, bitbuf) << 4), repcount += huffman_decode_one(decoder, bitbuf); |
| 1155 | else |
| 1156 | rawmap[0] = lastcomp = val; |
| 1157 | } |
| 1158 | } |
| 1159 | |
| 1160 | /* then iterate through the hunks and extract the needed data */ |
| 1161 | uint64_t curoffset = firstoffs; |
| 1162 | uint32_t last_self = 0; |
| 1163 | uint64_t last_parent = 0; |
| 1164 | for (int hunknum = 0; hunknum < header->hunkcount; hunknum++) |
| 1165 | { |
| 1166 | uint8_t *rawmap = header->rawmap + (hunknum * 12); |
| 1167 | uint64_t offset = curoffset; |
| 1168 | uint32_t length = 0; |
| 1169 | uint16_t crc = 0; |
| 1170 | switch (rawmap[0]) |
| 1171 | { |
| 1172 | /* base types */ |
| 1173 | case COMPRESSION_TYPE_0: |
| 1174 | case COMPRESSION_TYPE_1: |
| 1175 | case COMPRESSION_TYPE_2: |
| 1176 | case COMPRESSION_TYPE_3: |
| 1177 | curoffset += length = bitstream_read(bitbuf, lengthbits); |
| 1178 | crc = bitstream_read(bitbuf, 16); |
| 1179 | break; |
| 1180 | |
| 1181 | case COMPRESSION_NONE: |
| 1182 | curoffset += length = header->hunkbytes; |
| 1183 | crc = bitstream_read(bitbuf, 16); |
| 1184 | break; |
| 1185 | |
| 1186 | case COMPRESSION_SELF: |
| 1187 | last_self = offset = bitstream_read(bitbuf, selfbits); |
| 1188 | break; |
| 1189 | |
| 1190 | case COMPRESSION_PARENT: |
| 1191 | offset = bitstream_read(bitbuf, parentbits); |
| 1192 | last_parent = offset; |
| 1193 | break; |
| 1194 | |
| 1195 | /* pseudo-types; convert into base types */ |
| 1196 | case COMPRESSION_SELF_1: |
| 1197 | last_self++; |
| 1198 | case COMPRESSION_SELF_0: |
| 1199 | rawmap[0] = COMPRESSION_SELF; |
| 1200 | offset = last_self; |
| 1201 | break; |
| 1202 | |
| 1203 | case COMPRESSION_PARENT_SELF: |
| 1204 | rawmap[0] = COMPRESSION_PARENT; |
| 1205 | last_parent = offset = ( ((uint64_t)hunknum) * ((uint64_t)header->hunkbytes) ) / header->unitbytes; |
| 1206 | break; |
| 1207 | |
| 1208 | case COMPRESSION_PARENT_1: |
| 1209 | last_parent += header->hunkbytes / header->unitbytes; |
| 1210 | case COMPRESSION_PARENT_0: |
| 1211 | rawmap[0] = COMPRESSION_PARENT; |
| 1212 | offset = last_parent; |
| 1213 | break; |
| 1214 | } |
| 1215 | /* UINT24 length */ |
| 1216 | put_bigendian_uint24(&rawmap[1], length); |
| 1217 | |
| 1218 | /* UINT48 offset */ |
| 1219 | put_bigendian_uint48(&rawmap[4], offset); |
| 1220 | |
| 1221 | /* crc16 */ |
| 1222 | put_bigendian_uint16(&rawmap[10], crc); |
| 1223 | } |
| 1224 | |
| 1225 | free(compressed); |
| 1226 | free(bitbuf); |
| 1227 | free(decoder->lookup); |
| 1228 | free(decoder->huffnode); |
| 1229 | free(decoder); |
| 1230 | |
| 1231 | /* verify the final CRC */ |
| 1232 | if (crc16(&header->rawmap[0], header->hunkcount * 12) != mapcrc) |
| 1233 | return CHDERR_DECOMPRESSION_ERROR; |
| 1234 | |
| 1235 | return CHDERR_NONE; |
| 1236 | } |
| 1237 | |
| 1238 | /*------------------------------------------------- |
| 1239 | map_extract_old - extract a single map |
| 1240 | entry in old format from the datastream |
| 1241 | -------------------------------------------------*/ |
| 1242 | |
| 1243 | static inline void map_extract_old(const UINT8 *base, map_entry *entry, UINT32 hunkbytes) |
| 1244 | { |
| 1245 | entry->offset = get_bigendian_uint64(&base[0]); |
| 1246 | entry->crc = 0; |
| 1247 | entry->length = entry->offset >> 44; |
| 1248 | entry->flags = MAP_ENTRY_FLAG_NO_CRC | ((entry->length == hunkbytes) ? V34_MAP_ENTRY_TYPE_UNCOMPRESSED : V34_MAP_ENTRY_TYPE_COMPRESSED); |
| 1249 | #ifdef __MWERKS__ |
| 1250 | entry->offset = entry->offset & 0x00000FFFFFFFFFFFLL; |
| 1251 | #else |
| 1252 | entry->offset = (entry->offset << 20) >> 20; |
| 1253 | #endif |
| 1254 | } |
| 1255 | |
| 1256 | /*************************************************************************** |
| 1257 | CHD FILE MANAGEMENT |
| 1258 | ***************************************************************************/ |
| 1259 | |
| 1260 | /*------------------------------------------------- |
| 1261 | chd_open_file - open a CHD file for access |
| 1262 | -------------------------------------------------*/ |
| 1263 | |
| 1264 | chd_error chd_open_file(core_file *file, int mode, chd_file *parent, chd_file **chd) |
| 1265 | { |
| 1266 | chd_file *newchd = NULL; |
| 1267 | chd_error err; |
| 1268 | int intfnum; |
| 1269 | |
| 1270 | /* verify parameters */ |
| 1271 | if (file == NULL) |
| 1272 | EARLY_EXIT(err = CHDERR_INVALID_PARAMETER); |
| 1273 | |
| 1274 | /* punt if invalid parent */ |
| 1275 | if (parent != NULL && parent->cookie != COOKIE_VALUE) |
| 1276 | EARLY_EXIT(err = CHDERR_INVALID_PARAMETER); |
| 1277 | |
| 1278 | /* allocate memory for the final result */ |
| 1279 | newchd = (chd_file *)malloc(sizeof(**chd)); |
| 1280 | if (newchd == NULL) |
| 1281 | EARLY_EXIT(err = CHDERR_OUT_OF_MEMORY); |
| 1282 | memset(newchd, 0, sizeof(*newchd)); |
| 1283 | newchd->cookie = COOKIE_VALUE; |
| 1284 | newchd->parent = parent; |
| 1285 | newchd->file = file; |
| 1286 | |
| 1287 | /* now attempt to read the header */ |
| 1288 | err = header_read(newchd, &newchd->header); |
| 1289 | if (err != CHDERR_NONE) |
| 1290 | EARLY_EXIT(err); |
| 1291 | |
| 1292 | /* validate the header */ |
| 1293 | err = header_validate(&newchd->header); |
| 1294 | if (err != CHDERR_NONE) |
| 1295 | EARLY_EXIT(err); |
| 1296 | |
| 1297 | /* make sure we don't open a read-only file writeable */ |
| 1298 | if (mode == CHD_OPEN_READWRITE && !(newchd->header.flags & CHDFLAGS_IS_WRITEABLE)) |
| 1299 | EARLY_EXIT(err = CHDERR_FILE_NOT_WRITEABLE); |
| 1300 | |
| 1301 | /* also, never open an older version writeable */ |
| 1302 | if (mode == CHD_OPEN_READWRITE && newchd->header.version < CHD_HEADER_VERSION) |
| 1303 | EARLY_EXIT(err = CHDERR_UNSUPPORTED_VERSION); |
| 1304 | |
| 1305 | /* if we need a parent, make sure we have one */ |
| 1306 | if (parent == NULL && (newchd->header.flags & CHDFLAGS_HAS_PARENT)) |
| 1307 | EARLY_EXIT(err = CHDERR_REQUIRES_PARENT); |
| 1308 | |
| 1309 | /* make sure we have a valid parent */ |
| 1310 | if (parent != NULL) |
| 1311 | { |
| 1312 | /* check MD5 if it isn't empty */ |
| 1313 | if (memcmp(nullmd5, newchd->header.parentmd5, sizeof(newchd->header.parentmd5)) != 0 && |
| 1314 | memcmp(nullmd5, newchd->parent->header.md5, sizeof(newchd->parent->header.md5)) != 0 && |
| 1315 | memcmp(newchd->parent->header.md5, newchd->header.parentmd5, sizeof(newchd->header.parentmd5)) != 0) |
| 1316 | EARLY_EXIT(err = CHDERR_INVALID_PARENT); |
| 1317 | |
| 1318 | /* check SHA1 if it isn't empty */ |
| 1319 | if (memcmp(nullsha1, newchd->header.parentsha1, sizeof(newchd->header.parentsha1)) != 0 && |
| 1320 | memcmp(nullsha1, newchd->parent->header.sha1, sizeof(newchd->parent->header.sha1)) != 0 && |
| 1321 | memcmp(newchd->parent->header.sha1, newchd->header.parentsha1, sizeof(newchd->header.parentsha1)) != 0) |
| 1322 | EARLY_EXIT(err = CHDERR_INVALID_PARENT); |
| 1323 | } |
| 1324 | |
| 1325 | /* now read the hunk map */ |
| 1326 | if (newchd->header.version < 5) |
| 1327 | { |
| 1328 | err = map_read(newchd); |
| 1329 | } |
| 1330 | else |
| 1331 | { |
| 1332 | err = decompress_v5_map(newchd, &(newchd->header)); |
| 1333 | } |
| 1334 | if (err != CHDERR_NONE) |
| 1335 | EARLY_EXIT(err); |
| 1336 | |
| 1337 | |
| 1338 | /* allocate and init the hunk cache */ |
| 1339 | newchd->cache = (UINT8 *)malloc(newchd->header.hunkbytes); |
| 1340 | newchd->compare = (UINT8 *)malloc(newchd->header.hunkbytes); |
| 1341 | if (newchd->cache == NULL || newchd->compare == NULL) |
| 1342 | EARLY_EXIT(err = CHDERR_OUT_OF_MEMORY); |
| 1343 | newchd->cachehunk = ~0; |
| 1344 | newchd->comparehunk = ~0; |
| 1345 | |
| 1346 | /* allocate the temporary compressed buffer */ |
| 1347 | newchd->compressed = (UINT8 *)malloc(newchd->header.hunkbytes); |
| 1348 | if (newchd->compressed == NULL) |
| 1349 | EARLY_EXIT(err = CHDERR_OUT_OF_MEMORY); |
| 1350 | |
| 1351 | /* find the codec interface */ |
| 1352 | if (newchd->header.version < 5) |
| 1353 | { |
| 1354 | for (intfnum = 0; intfnum < ARRAY_LENGTH(codec_interfaces); intfnum++) |
| 1355 | { |
| 1356 | if (codec_interfaces[intfnum].compression == newchd->header.compression[0]) |
| 1357 | { |
| 1358 | newchd->codecintf[0] = &codec_interfaces[intfnum]; |
| 1359 | break; |
| 1360 | } |
| 1361 | } |
| 1362 | |
| 1363 | if (intfnum == ARRAY_LENGTH(codec_interfaces)) |
| 1364 | EARLY_EXIT(err = CHDERR_UNSUPPORTED_FORMAT); |
| 1365 | |
| 1366 | /* initialize the codec */ |
| 1367 | if (newchd->codecintf[0]->init != NULL) |
| 1368 | { |
| 1369 | err = (*newchd->codecintf[0]->init)(&newchd->zlib_codec_data, newchd->header.hunkbytes); |
| 1370 | if (err != CHDERR_NONE) |
| 1371 | EARLY_EXIT(err); |
| 1372 | } |
| 1373 | } |
| 1374 | else |
| 1375 | { |
| 1376 | /* verify the compression types and initialize the codecs */ |
| 1377 | for (int decompnum = 0; decompnum < ARRAY_LENGTH(newchd->header.compression); decompnum++) |
| 1378 | { |
| 1379 | for (int i = 0 ; i < ARRAY_LENGTH(codec_interfaces) ; i++) |
| 1380 | { |
| 1381 | if (codec_interfaces[i].compression == newchd->header.compression[decompnum]) |
| 1382 | { |
| 1383 | newchd->codecintf[decompnum] = &codec_interfaces[i]; |
| 1384 | break; |
| 1385 | } |
| 1386 | } |
| 1387 | |
| 1388 | if (newchd->codecintf[decompnum] == NULL && newchd->header.compression[decompnum] != 0) |
| 1389 | EARLY_EXIT(err = CHDERR_UNSUPPORTED_FORMAT); |
| 1390 | |
| 1391 | /* initialize the codec */ |
| 1392 | if (newchd->codecintf[decompnum]->init != NULL) |
| 1393 | { |
| 1394 | void* codec = NULL; |
| 1395 | switch (newchd->header.compression[decompnum]) |
| 1396 | { |
| 1397 | case CHD_CODEC_ZLIB: |
| 1398 | codec = &newchd->zlib_codec_data; |
| 1399 | break; |
| 1400 | |
| 1401 | case CHD_CODEC_CD_ZLIB: |
| 1402 | codec = &newchd->cdzl_codec_data; |
| 1403 | break; |
| 1404 | |
| 1405 | case CHD_CODEC_CD_LZMA: |
| 1406 | codec = &newchd->cdlz_codec_data; |
| 1407 | break; |
| 1408 | |
| 1409 | case CHD_CODEC_CD_FLAC: |
| 1410 | codec = &newchd->cdfl_codec_data; |
| 1411 | break; |
| 1412 | } |
| 1413 | |
| 1414 | if (codec == NULL) |
| 1415 | EARLY_EXIT(err = CHDERR_UNSUPPORTED_FORMAT); |
| 1416 | |
| 1417 | err = (*newchd->codecintf[decompnum]->init)(codec, newchd->header.hunkbytes); |
| 1418 | if (err != CHDERR_NONE) |
| 1419 | EARLY_EXIT(err); |
| 1420 | } |
| 1421 | } |
| 1422 | } |
| 1423 | |
| 1424 | /* all done */ |
| 1425 | *chd = newchd; |
| 1426 | return CHDERR_NONE; |
| 1427 | |
| 1428 | cleanup: |
| 1429 | if (newchd != NULL) |
| 1430 | chd_close(newchd); |
| 1431 | return err; |
| 1432 | } |
| 1433 | |
| 1434 | /*------------------------------------------------- |
| 1435 | chd_precache - precache underlying file in |
| 1436 | memory |
| 1437 | -------------------------------------------------*/ |
| 1438 | |
| 1439 | chd_error chd_precache(chd_file *chd) |
| 1440 | { |
| 1441 | ssize_t size, count; |
| 1442 | |
| 1443 | if (chd->file_cache == NULL) |
| 1444 | { |
| 1445 | core_fseek(chd->file, 0, SEEK_END); |
| 1446 | size = core_ftell(chd->file); |
| 1447 | if (size <= 0) |
| 1448 | return CHDERR_INVALID_DATA; |
| 1449 | chd->file_cache = malloc(size); |
| 1450 | if (chd->file_cache == NULL) |
| 1451 | return CHDERR_OUT_OF_MEMORY; |
| 1452 | core_fseek(chd->file, 0, SEEK_SET); |
| 1453 | count = core_fread(chd->file, chd->file_cache, size); |
| 1454 | if (count != size) |
| 1455 | { |
| 1456 | free(chd->file_cache); |
| 1457 | chd->file_cache = NULL; |
| 1458 | return CHDERR_READ_ERROR; |
| 1459 | } |
| 1460 | } |
| 1461 | |
| 1462 | return CHDERR_NONE; |
| 1463 | } |
| 1464 | |
| 1465 | /*------------------------------------------------- |
| 1466 | chd_open - open a CHD file by |
| 1467 | filename |
| 1468 | -------------------------------------------------*/ |
| 1469 | |
| 1470 | chd_error chd_open(const char *filename, int mode, chd_file *parent, chd_file **chd) |
| 1471 | { |
| 1472 | chd_error err; |
| 1473 | core_file *file = NULL; |
| 1474 | UINT32 openflags; |
| 1475 | |
| 1476 | /* choose the proper mode */ |
| 1477 | switch(mode) |
| 1478 | { |
| 1479 | case CHD_OPEN_READ: |
| 1480 | break; |
| 1481 | |
| 1482 | default: |
| 1483 | err = CHDERR_INVALID_PARAMETER; |
| 1484 | goto cleanup; |
| 1485 | } |
| 1486 | |
| 1487 | /* open the file */ |
| 1488 | file = core_fopen(filename); |
| 1489 | if (file == 0) |
| 1490 | { |
| 1491 | err = CHDERR_FILE_NOT_FOUND; |
| 1492 | goto cleanup; |
| 1493 | } |
| 1494 | |
| 1495 | /* now open the CHD */ |
| 1496 | err = chd_open_file(file, mode, parent, chd); |
| 1497 | if (err != CHDERR_NONE) |
| 1498 | goto cleanup; |
| 1499 | |
| 1500 | /* we now own this file */ |
| 1501 | (*chd)->owns_file = TRUE; |
| 1502 | |
| 1503 | cleanup: |
| 1504 | if ((err != CHDERR_NONE) && (file != NULL)) |
| 1505 | core_fclose(file); |
| 1506 | return err; |
| 1507 | } |
| 1508 | |
| 1509 | /*------------------------------------------------- |
| 1510 | chd_close - close a CHD file for access |
| 1511 | -------------------------------------------------*/ |
| 1512 | |
| 1513 | void chd_close(chd_file *chd) |
| 1514 | { |
| 1515 | /* punt if NULL or invalid */ |
| 1516 | if (chd == NULL || chd->cookie != COOKIE_VALUE) |
| 1517 | return; |
| 1518 | |
| 1519 | /* deinit the codec */ |
| 1520 | if (chd->header.version < 5) |
| 1521 | { |
| 1522 | if (chd->codecintf[0] != NULL && chd->codecintf[0]->free != NULL) |
| 1523 | (*chd->codecintf[0]->free)(&chd->zlib_codec_data); |
| 1524 | } |
| 1525 | else |
| 1526 | { |
| 1527 | /* Free the codecs */ |
| 1528 | for (int i = 0 ; i < ARRAY_LENGTH(chd->codecintf); i++) |
| 1529 | { |
| 1530 | void* codec = NULL; |
| 1531 | |
| 1532 | if (chd->codecintf[i] == NULL) |
| 1533 | continue; |
| 1534 | |
| 1535 | switch (chd->codecintf[i]->compression) |
| 1536 | { |
| 1537 | case CHD_CODEC_CD_LZMA: |
| 1538 | codec = &chd->cdlz_codec_data; |
| 1539 | break; |
| 1540 | |
| 1541 | case CHD_CODEC_ZLIB: |
| 1542 | codec = &chd->zlib_codec_data; |
| 1543 | break; |
| 1544 | |
| 1545 | case CHD_CODEC_CD_ZLIB: |
| 1546 | codec = &chd->cdzl_codec_data; |
| 1547 | break; |
| 1548 | |
| 1549 | case CHD_CODEC_CD_FLAC: |
| 1550 | codec = &chd->cdfl_codec_data; |
| 1551 | break; |
| 1552 | } |
| 1553 | |
| 1554 | if (codec) |
| 1555 | { |
| 1556 | (*chd->codecintf[i]->free)(codec); |
| 1557 | } |
| 1558 | } |
| 1559 | |
| 1560 | /* Free the raw map */ |
| 1561 | if (chd->header.rawmap != NULL) |
| 1562 | free(chd->header.rawmap); |
| 1563 | } |
| 1564 | |
| 1565 | /* free the compressed data buffer */ |
| 1566 | if (chd->compressed != NULL) |
| 1567 | free(chd->compressed); |
| 1568 | |
| 1569 | /* free the hunk cache and compare data */ |
| 1570 | if (chd->compare != NULL) |
| 1571 | free(chd->compare); |
| 1572 | if (chd->cache != NULL) |
| 1573 | free(chd->cache); |
| 1574 | |
| 1575 | /* free the hunk map */ |
| 1576 | if (chd->map != NULL) |
| 1577 | free(chd->map); |
| 1578 | |
| 1579 | /* free the CRC table */ |
| 1580 | if (chd->crctable != NULL) |
| 1581 | free(chd->crctable); |
| 1582 | |
| 1583 | /* free the CRC map */ |
| 1584 | if (chd->crcmap != NULL) |
| 1585 | free(chd->crcmap); |
| 1586 | |
| 1587 | /* close the file */ |
| 1588 | if (chd->owns_file && chd->file != NULL) |
| 1589 | core_fclose(chd->file); |
| 1590 | |
| 1591 | if (PRINTF_MAX_HUNK) printf("Max hunk = %d/%d\n", chd->maxhunk, chd->header.totalhunks); |
| 1592 | |
| 1593 | if (chd->file_cache) |
| 1594 | free(chd->file_cache); |
| 1595 | |
| 1596 | /* free our memory */ |
| 1597 | free(chd); |
| 1598 | } |
| 1599 | |
| 1600 | /*------------------------------------------------- |
| 1601 | chd_core_file - return the associated |
| 1602 | core_file |
| 1603 | -------------------------------------------------*/ |
| 1604 | |
| 1605 | core_file *chd_core_file(chd_file *chd) |
| 1606 | { |
| 1607 | return chd->file; |
| 1608 | } |
| 1609 | |
| 1610 | /*------------------------------------------------- |
| 1611 | chd_error_string - return an error string for |
| 1612 | the given CHD error |
| 1613 | -------------------------------------------------*/ |
| 1614 | |
| 1615 | const char *chd_error_string(chd_error err) |
| 1616 | { |
| 1617 | switch (err) |
| 1618 | { |
| 1619 | case CHDERR_NONE: return "no error"; |
| 1620 | case CHDERR_NO_INTERFACE: return "no drive interface"; |
| 1621 | case CHDERR_OUT_OF_MEMORY: return "out of memory"; |
| 1622 | case CHDERR_INVALID_FILE: return "invalid file"; |
| 1623 | case CHDERR_INVALID_PARAMETER: return "invalid parameter"; |
| 1624 | case CHDERR_INVALID_DATA: return "invalid data"; |
| 1625 | case CHDERR_FILE_NOT_FOUND: return "file not found"; |
| 1626 | case CHDERR_REQUIRES_PARENT: return "requires parent"; |
| 1627 | case CHDERR_FILE_NOT_WRITEABLE: return "file not writeable"; |
| 1628 | case CHDERR_READ_ERROR: return "read error"; |
| 1629 | case CHDERR_WRITE_ERROR: return "write error"; |
| 1630 | case CHDERR_CODEC_ERROR: return "codec error"; |
| 1631 | case CHDERR_INVALID_PARENT: return "invalid parent"; |
| 1632 | case CHDERR_HUNK_OUT_OF_RANGE: return "hunk out of range"; |
| 1633 | case CHDERR_DECOMPRESSION_ERROR: return "decompression error"; |
| 1634 | case CHDERR_COMPRESSION_ERROR: return "compression error"; |
| 1635 | case CHDERR_CANT_CREATE_FILE: return "can't create file"; |
| 1636 | case CHDERR_CANT_VERIFY: return "can't verify file"; |
| 1637 | case CHDERR_NOT_SUPPORTED: return "operation not supported"; |
| 1638 | case CHDERR_METADATA_NOT_FOUND: return "can't find metadata"; |
| 1639 | case CHDERR_INVALID_METADATA_SIZE: return "invalid metadata size"; |
| 1640 | case CHDERR_UNSUPPORTED_VERSION: return "unsupported CHD version"; |
| 1641 | case CHDERR_VERIFY_INCOMPLETE: return "incomplete verify"; |
| 1642 | case CHDERR_INVALID_METADATA: return "invalid metadata"; |
| 1643 | case CHDERR_INVALID_STATE: return "invalid state"; |
| 1644 | case CHDERR_OPERATION_PENDING: return "operation pending"; |
| 1645 | case CHDERR_NO_ASYNC_OPERATION: return "no async operation in progress"; |
| 1646 | case CHDERR_UNSUPPORTED_FORMAT: return "unsupported format"; |
| 1647 | default: return "undocumented error"; |
| 1648 | } |
| 1649 | } |
| 1650 | |
| 1651 | /*************************************************************************** |
| 1652 | CHD HEADER MANAGEMENT |
| 1653 | ***************************************************************************/ |
| 1654 | |
| 1655 | /*------------------------------------------------- |
| 1656 | chd_get_header - return a pointer to the |
| 1657 | extracted header data |
| 1658 | -------------------------------------------------*/ |
| 1659 | |
| 1660 | const chd_header *chd_get_header(chd_file *chd) |
| 1661 | { |
| 1662 | /* punt if NULL or invalid */ |
| 1663 | if (chd == NULL || chd->cookie != COOKIE_VALUE) |
| 1664 | return NULL; |
| 1665 | |
| 1666 | return &chd->header; |
| 1667 | } |
| 1668 | |
| 1669 | /*************************************************************************** |
| 1670 | CORE DATA READ/WRITE |
| 1671 | ***************************************************************************/ |
| 1672 | |
| 1673 | /*------------------------------------------------- |
| 1674 | chd_read - read a single hunk from the CHD |
| 1675 | file |
| 1676 | -------------------------------------------------*/ |
| 1677 | |
| 1678 | chd_error chd_read(chd_file *chd, UINT32 hunknum, void *buffer) |
| 1679 | { |
| 1680 | /* punt if NULL or invalid */ |
| 1681 | if (chd == NULL || chd->cookie != COOKIE_VALUE) |
| 1682 | return CHDERR_INVALID_PARAMETER; |
| 1683 | |
| 1684 | /* if we're past the end, fail */ |
| 1685 | if (hunknum >= chd->header.totalhunks) |
| 1686 | return CHDERR_HUNK_OUT_OF_RANGE; |
| 1687 | |
| 1688 | /* perform the read */ |
| 1689 | return hunk_read_into_memory(chd, hunknum, (UINT8 *)buffer); |
| 1690 | } |
| 1691 | |
| 1692 | /*************************************************************************** |
| 1693 | METADATA MANAGEMENT |
| 1694 | ***************************************************************************/ |
| 1695 | |
| 1696 | /*------------------------------------------------- |
| 1697 | chd_get_metadata - get the indexed metadata |
| 1698 | of the given type |
| 1699 | -------------------------------------------------*/ |
| 1700 | |
| 1701 | chd_error chd_get_metadata(chd_file *chd, UINT32 searchtag, UINT32 searchindex, void *output, UINT32 outputlen, UINT32 *resultlen, UINT32 *resulttag, UINT8 *resultflags) |
| 1702 | { |
| 1703 | metadata_entry metaentry; |
| 1704 | chd_error err; |
| 1705 | UINT32 count; |
| 1706 | |
| 1707 | /* if we didn't find it, just return */ |
| 1708 | err = metadata_find_entry(chd, searchtag, searchindex, &metaentry); |
| 1709 | if (err != CHDERR_NONE) |
| 1710 | { |
| 1711 | /* unless we're an old version and they are requesting hard disk metadata */ |
| 1712 | if (chd->header.version < 3 && (searchtag == HARD_DISK_METADATA_TAG || searchtag == CHDMETATAG_WILDCARD) && searchindex == 0) |
| 1713 | { |
| 1714 | char faux_metadata[256]; |
| 1715 | UINT32 faux_length; |
| 1716 | |
| 1717 | /* fill in the faux metadata */ |
| 1718 | sprintf(faux_metadata, HARD_DISK_METADATA_FORMAT, chd->header.obsolete_cylinders, chd->header.obsolete_heads, chd->header.obsolete_sectors, chd->header.hunkbytes / chd->header.obsolete_hunksize); |
| 1719 | faux_length = (UINT32)strlen(faux_metadata) + 1; |
| 1720 | |
| 1721 | /* copy the metadata itself */ |
| 1722 | memcpy(output, faux_metadata, MIN(outputlen, faux_length)); |
| 1723 | |
| 1724 | /* return the length of the data and the tag */ |
| 1725 | if (resultlen != NULL) |
| 1726 | *resultlen = faux_length; |
| 1727 | if (resulttag != NULL) |
| 1728 | *resulttag = HARD_DISK_METADATA_TAG; |
| 1729 | return CHDERR_NONE; |
| 1730 | } |
| 1731 | return err; |
| 1732 | } |
| 1733 | |
| 1734 | /* read the metadata */ |
| 1735 | outputlen = MIN(outputlen, metaentry.length); |
| 1736 | core_fseek(chd->file, metaentry.offset + METADATA_HEADER_SIZE, SEEK_SET); |
| 1737 | count = core_fread(chd->file, output, outputlen); |
| 1738 | if (count != outputlen) |
| 1739 | return CHDERR_READ_ERROR; |
| 1740 | |
| 1741 | /* return the length of the data and the tag */ |
| 1742 | if (resultlen != NULL) |
| 1743 | *resultlen = metaentry.length; |
| 1744 | if (resulttag != NULL) |
| 1745 | *resulttag = metaentry.metatag; |
| 1746 | if (resultflags != NULL) |
| 1747 | *resultflags = metaentry.flags; |
| 1748 | return CHDERR_NONE; |
| 1749 | } |
| 1750 | |
| 1751 | /*************************************************************************** |
| 1752 | CODEC INTERFACES |
| 1753 | ***************************************************************************/ |
| 1754 | |
| 1755 | /*------------------------------------------------- |
| 1756 | chd_codec_config - set internal codec |
| 1757 | parameters |
| 1758 | -------------------------------------------------*/ |
| 1759 | |
| 1760 | chd_error chd_codec_config(chd_file *chd, int param, void *config) |
| 1761 | { |
| 1762 | return CHDERR_INVALID_PARAMETER; |
| 1763 | } |
| 1764 | |
| 1765 | /*------------------------------------------------- |
| 1766 | chd_get_codec_name - get the name of a |
| 1767 | particular codec |
| 1768 | -------------------------------------------------*/ |
| 1769 | |
| 1770 | const char *chd_get_codec_name(UINT32 codec) |
| 1771 | { |
| 1772 | return "Unknown"; |
| 1773 | } |
| 1774 | |
| 1775 | /*************************************************************************** |
| 1776 | INTERNAL HEADER OPERATIONS |
| 1777 | ***************************************************************************/ |
| 1778 | |
| 1779 | /*------------------------------------------------- |
| 1780 | header_validate - check the validity of a |
| 1781 | CHD header |
| 1782 | -------------------------------------------------*/ |
| 1783 | |
| 1784 | static chd_error header_validate(const chd_header *header) |
| 1785 | { |
| 1786 | int intfnum; |
| 1787 | |
| 1788 | /* require a valid version */ |
| 1789 | if (header->version == 0 || header->version > CHD_HEADER_VERSION) |
| 1790 | return CHDERR_UNSUPPORTED_VERSION; |
| 1791 | |
| 1792 | /* require a valid length */ |
| 1793 | if ((header->version == 1 && header->length != CHD_V1_HEADER_SIZE) || |
| 1794 | (header->version == 2 && header->length != CHD_V2_HEADER_SIZE) || |
| 1795 | (header->version == 3 && header->length != CHD_V3_HEADER_SIZE) || |
| 1796 | (header->version == 4 && header->length != CHD_V4_HEADER_SIZE) || |
| 1797 | (header->version == 5 && header->length != CHD_V5_HEADER_SIZE)) |
| 1798 | return CHDERR_INVALID_PARAMETER; |
| 1799 | |
| 1800 | /* Do not validate v5 header */ |
| 1801 | if (header->version <= 4) |
| 1802 | { |
| 1803 | /* require valid flags */ |
| 1804 | if (header->flags & CHDFLAGS_UNDEFINED) |
| 1805 | return CHDERR_INVALID_PARAMETER; |
| 1806 | |
| 1807 | /* require a supported compression mechanism */ |
| 1808 | for (intfnum = 0; intfnum < ARRAY_LENGTH(codec_interfaces); intfnum++) |
| 1809 | if (codec_interfaces[intfnum].compression == header->compression[0]) |
| 1810 | break; |
| 1811 | |
| 1812 | if (intfnum == ARRAY_LENGTH(codec_interfaces)) |
| 1813 | return CHDERR_INVALID_PARAMETER; |
| 1814 | |
| 1815 | /* require a valid hunksize */ |
| 1816 | if (header->hunkbytes == 0 || header->hunkbytes >= 65536 * 256) |
| 1817 | return CHDERR_INVALID_PARAMETER; |
| 1818 | |
| 1819 | /* require a valid hunk count */ |
| 1820 | if (header->totalhunks == 0) |
| 1821 | return CHDERR_INVALID_PARAMETER; |
| 1822 | |
| 1823 | /* require a valid MD5 and/or SHA1 if we're using a parent */ |
| 1824 | if ((header->flags & CHDFLAGS_HAS_PARENT) && memcmp(header->parentmd5, nullmd5, sizeof(nullmd5)) == 0 && memcmp(header->parentsha1, nullsha1, sizeof(nullsha1)) == 0) |
| 1825 | return CHDERR_INVALID_PARAMETER; |
| 1826 | |
| 1827 | /* if we're V3 or later, the obsolete fields must be 0 */ |
| 1828 | if (header->version >= 3 && |
| 1829 | (header->obsolete_cylinders != 0 || header->obsolete_sectors != 0 || |
| 1830 | header->obsolete_heads != 0 || header->obsolete_hunksize != 0)) |
| 1831 | return CHDERR_INVALID_PARAMETER; |
| 1832 | |
| 1833 | /* if we're pre-V3, the obsolete fields must NOT be 0 */ |
| 1834 | if (header->version < 3 && |
| 1835 | (header->obsolete_cylinders == 0 || header->obsolete_sectors == 0 || |
| 1836 | header->obsolete_heads == 0 || header->obsolete_hunksize == 0)) |
| 1837 | return CHDERR_INVALID_PARAMETER; |
| 1838 | } |
| 1839 | |
| 1840 | return CHDERR_NONE; |
| 1841 | } |
| 1842 | |
| 1843 | /*------------------------------------------------- |
| 1844 | header_guess_unitbytes - for older CHD formats, |
| 1845 | guess at the bytes/unit based on metadata |
| 1846 | -------------------------------------------------*/ |
| 1847 | |
| 1848 | static UINT32 header_guess_unitbytes(chd_file *chd) |
| 1849 | { |
| 1850 | /* look for hard disk metadata; if found, then the unit size == sector size */ |
| 1851 | char metadata[512]; |
| 1852 | int i0, i1, i2, i3; |
| 1853 | if (chd_get_metadata(chd, HARD_DISK_METADATA_TAG, 0, metadata, sizeof(metadata), NULL, NULL, NULL) == CHDERR_NONE && |
| 1854 | sscanf(metadata, HARD_DISK_METADATA_FORMAT, &i0, &i1, &i2, &i3) == 4) |
| 1855 | return i3; |
| 1856 | |
| 1857 | /* look for CD-ROM metadata; if found, then the unit size == CD frame size */ |
| 1858 | if (chd_get_metadata(chd, CDROM_OLD_METADATA_TAG, 0, metadata, sizeof(metadata), NULL, NULL, NULL) == CHDERR_NONE || |
| 1859 | chd_get_metadata(chd, CDROM_TRACK_METADATA_TAG, 0, metadata, sizeof(metadata), NULL, NULL, NULL) == CHDERR_NONE || |
| 1860 | chd_get_metadata(chd, CDROM_TRACK_METADATA2_TAG, 0, metadata, sizeof(metadata), NULL, NULL, NULL) == CHDERR_NONE || |
| 1861 | chd_get_metadata(chd, GDROM_OLD_METADATA_TAG, 0, metadata, sizeof(metadata), NULL, NULL, NULL) == CHDERR_NONE || |
| 1862 | chd_get_metadata(chd, GDROM_TRACK_METADATA_TAG, 0, metadata, sizeof(metadata), NULL, NULL, NULL) == CHDERR_NONE) |
| 1863 | return CD_FRAME_SIZE; |
| 1864 | |
| 1865 | /* otherwise, just map 1:1 with the hunk size */ |
| 1866 | return chd->header.hunkbytes; |
| 1867 | } |
| 1868 | |
| 1869 | /*------------------------------------------------- |
| 1870 | header_read - read a CHD header into the |
| 1871 | internal data structure |
| 1872 | -------------------------------------------------*/ |
| 1873 | |
| 1874 | static chd_error header_read(chd_file *chd, chd_header *header) |
| 1875 | { |
| 1876 | UINT8 rawheader[CHD_MAX_HEADER_SIZE]; |
| 1877 | UINT32 count; |
| 1878 | |
| 1879 | /* punt if NULL */ |
| 1880 | if (header == NULL) |
| 1881 | return CHDERR_INVALID_PARAMETER; |
| 1882 | |
| 1883 | /* punt if invalid file */ |
| 1884 | if (chd->file == NULL) |
| 1885 | return CHDERR_INVALID_FILE; |
| 1886 | |
| 1887 | /* seek and read */ |
| 1888 | core_fseek(chd->file, 0, SEEK_SET); |
| 1889 | count = core_fread(chd->file, rawheader, sizeof(rawheader)); |
| 1890 | if (count != sizeof(rawheader)) |
| 1891 | return CHDERR_READ_ERROR; |
| 1892 | |
| 1893 | /* verify the tag */ |
| 1894 | if (strncmp((char *)rawheader, "MComprHD", 8) != 0) |
| 1895 | return CHDERR_INVALID_DATA; |
| 1896 | |
| 1897 | /* extract the direct data */ |
| 1898 | memset(header, 0, sizeof(*header)); |
| 1899 | header->length = get_bigendian_uint32(&rawheader[8]); |
| 1900 | header->version = get_bigendian_uint32(&rawheader[12]); |
| 1901 | |
| 1902 | /* make sure it's a version we understand */ |
| 1903 | if (header->version == 0 || header->version > CHD_HEADER_VERSION) |
| 1904 | return CHDERR_UNSUPPORTED_VERSION; |
| 1905 | |
| 1906 | /* make sure the length is expected */ |
| 1907 | if ((header->version == 1 && header->length != CHD_V1_HEADER_SIZE) || |
| 1908 | (header->version == 2 && header->length != CHD_V2_HEADER_SIZE) || |
| 1909 | (header->version == 3 && header->length != CHD_V3_HEADER_SIZE) || |
| 1910 | (header->version == 4 && header->length != CHD_V4_HEADER_SIZE) || |
| 1911 | (header->version == 5 && header->length != CHD_V5_HEADER_SIZE)) |
| 1912 | |
| 1913 | return CHDERR_INVALID_DATA; |
| 1914 | |
| 1915 | /* extract the common data */ |
| 1916 | header->flags = get_bigendian_uint32(&rawheader[16]); |
| 1917 | header->compression[0] = get_bigendian_uint32(&rawheader[20]); |
| 1918 | header->compression[1] = CHD_CODEC_NONE; |
| 1919 | header->compression[2] = CHD_CODEC_NONE; |
| 1920 | header->compression[3] = CHD_CODEC_NONE; |
| 1921 | |
| 1922 | /* extract the V1/V2-specific data */ |
| 1923 | if (header->version < 3) |
| 1924 | { |
| 1925 | int seclen = (header->version == 1) ? CHD_V1_SECTOR_SIZE : get_bigendian_uint32(&rawheader[76]); |
| 1926 | header->obsolete_hunksize = get_bigendian_uint32(&rawheader[24]); |
| 1927 | header->totalhunks = get_bigendian_uint32(&rawheader[28]); |
| 1928 | header->obsolete_cylinders = get_bigendian_uint32(&rawheader[32]); |
| 1929 | header->obsolete_heads = get_bigendian_uint32(&rawheader[36]); |
| 1930 | header->obsolete_sectors = get_bigendian_uint32(&rawheader[40]); |
| 1931 | memcpy(header->md5, &rawheader[44], CHD_MD5_BYTES); |
| 1932 | memcpy(header->parentmd5, &rawheader[60], CHD_MD5_BYTES); |
| 1933 | header->logicalbytes = (UINT64)header->obsolete_cylinders * (UINT64)header->obsolete_heads * (UINT64)header->obsolete_sectors * (UINT64)seclen; |
| 1934 | header->hunkbytes = seclen * header->obsolete_hunksize; |
| 1935 | header->unitbytes = header_guess_unitbytes(chd); |
| 1936 | header->unitcount = (header->logicalbytes + header->unitbytes - 1) / header->unitbytes; |
| 1937 | header->metaoffset = 0; |
| 1938 | } |
| 1939 | |
| 1940 | /* extract the V3-specific data */ |
| 1941 | else if (header->version == 3) |
| 1942 | { |
| 1943 | header->totalhunks = get_bigendian_uint32(&rawheader[24]); |
| 1944 | header->logicalbytes = get_bigendian_uint64(&rawheader[28]); |
| 1945 | header->metaoffset = get_bigendian_uint64(&rawheader[36]); |
| 1946 | memcpy(header->md5, &rawheader[44], CHD_MD5_BYTES); |
| 1947 | memcpy(header->parentmd5, &rawheader[60], CHD_MD5_BYTES); |
| 1948 | header->hunkbytes = get_bigendian_uint32(&rawheader[76]); |
| 1949 | header->unitbytes = header_guess_unitbytes(chd); |
| 1950 | header->unitcount = (header->logicalbytes + header->unitbytes - 1) / header->unitbytes; |
| 1951 | memcpy(header->sha1, &rawheader[80], CHD_SHA1_BYTES); |
| 1952 | memcpy(header->parentsha1, &rawheader[100], CHD_SHA1_BYTES); |
| 1953 | } |
| 1954 | |
| 1955 | /* extract the V4-specific data */ |
| 1956 | else if (header->version == 4) |
| 1957 | { |
| 1958 | header->totalhunks = get_bigendian_uint32(&rawheader[24]); |
| 1959 | header->logicalbytes = get_bigendian_uint64(&rawheader[28]); |
| 1960 | header->metaoffset = get_bigendian_uint64(&rawheader[36]); |
| 1961 | header->hunkbytes = get_bigendian_uint32(&rawheader[44]); |
| 1962 | header->unitbytes = header_guess_unitbytes(chd); |
| 1963 | header->unitcount = (header->logicalbytes + header->unitbytes - 1) / header->unitbytes; |
| 1964 | memcpy(header->sha1, &rawheader[48], CHD_SHA1_BYTES); |
| 1965 | memcpy(header->parentsha1, &rawheader[68], CHD_SHA1_BYTES); |
| 1966 | memcpy(header->rawsha1, &rawheader[88], CHD_SHA1_BYTES); |
| 1967 | } |
| 1968 | |
| 1969 | /* extract the V5-specific data */ |
| 1970 | else if (header->version == 5) |
| 1971 | { |
| 1972 | /* TODO */ |
| 1973 | header->compression[0] = get_bigendian_uint32(&rawheader[16]); |
| 1974 | header->compression[1] = get_bigendian_uint32(&rawheader[20]); |
| 1975 | header->compression[2] = get_bigendian_uint32(&rawheader[24]); |
| 1976 | header->compression[3] = get_bigendian_uint32(&rawheader[28]); |
| 1977 | header->logicalbytes = get_bigendian_uint64(&rawheader[32]); |
| 1978 | header->mapoffset = get_bigendian_uint64(&rawheader[40]); |
| 1979 | header->metaoffset = get_bigendian_uint64(&rawheader[48]); |
| 1980 | header->hunkbytes = get_bigendian_uint32(&rawheader[56]); |
| 1981 | header->hunkcount = (header->logicalbytes + header->hunkbytes - 1) / header->hunkbytes; |
| 1982 | header->unitbytes = get_bigendian_uint32(&rawheader[60]); |
| 1983 | header->unitcount = (header->logicalbytes + header->unitbytes - 1) / header->unitbytes; |
| 1984 | memcpy(header->sha1, &rawheader[84], CHD_SHA1_BYTES); |
| 1985 | memcpy(header->parentsha1, &rawheader[104], CHD_SHA1_BYTES); |
| 1986 | memcpy(header->rawsha1, &rawheader[64], CHD_SHA1_BYTES); |
| 1987 | |
| 1988 | /* determine properties of map entries */ |
| 1989 | header->mapentrybytes = compressed(header) ? 12 : 4; |
| 1990 | |
| 1991 | /* hack */ |
| 1992 | header->totalhunks = header->hunkcount; |
| 1993 | } |
| 1994 | |
| 1995 | /* Unknown version */ |
| 1996 | else |
| 1997 | { |
| 1998 | /* TODO */ |
| 1999 | } |
| 2000 | |
| 2001 | /* guess it worked */ |
| 2002 | return CHDERR_NONE; |
| 2003 | } |
| 2004 | |
| 2005 | /*************************************************************************** |
| 2006 | INTERNAL HUNK READ/WRITE |
| 2007 | ***************************************************************************/ |
| 2008 | |
| 2009 | /*------------------------------------------------- |
| 2010 | hunk_read_compressed - read a compressed |
| 2011 | hunk |
| 2012 | -------------------------------------------------*/ |
| 2013 | |
| 2014 | static UINT8* hunk_read_compressed(chd_file *chd, UINT64 offset, size_t size) |
| 2015 | { |
| 2016 | ssize_t bytes; |
| 2017 | if (chd->file_cache != NULL) |
| 2018 | { |
| 2019 | return chd->file_cache + offset; |
| 2020 | } |
| 2021 | else |
| 2022 | { |
| 2023 | core_fseek(chd->file, offset, SEEK_SET); |
| 2024 | bytes = core_fread(chd->file, chd->compressed, size); |
| 2025 | if (bytes != size) |
| 2026 | return NULL; |
| 2027 | return chd->compressed; |
| 2028 | } |
| 2029 | } |
| 2030 | |
| 2031 | /*------------------------------------------------- |
| 2032 | hunk_read_uncompressed - read an uncompressed |
| 2033 | hunk |
| 2034 | -------------------------------------------------*/ |
| 2035 | |
| 2036 | static chd_error hunk_read_uncompressed(chd_file *chd, UINT64 offset, size_t size, UINT8 *dest) |
| 2037 | { |
| 2038 | ssize_t bytes; |
| 2039 | if (chd->file_cache != NULL) |
| 2040 | { |
| 2041 | memcpy(dest, chd->file_cache + offset, size); |
| 2042 | } |
| 2043 | else |
| 2044 | { |
| 2045 | core_fseek(chd->file, offset, SEEK_SET); |
| 2046 | bytes = core_fread(chd->file, dest, size); |
| 2047 | if (bytes != size) |
| 2048 | return CHDERR_READ_ERROR; |
| 2049 | } |
| 2050 | return CHDERR_NONE; |
| 2051 | } |
| 2052 | |
| 2053 | /*------------------------------------------------- |
| 2054 | hunk_read_into_cache - read a hunk into |
| 2055 | the CHD's hunk cache |
| 2056 | -------------------------------------------------*/ |
| 2057 | |
| 2058 | static chd_error hunk_read_into_cache(chd_file *chd, UINT32 hunknum) |
| 2059 | { |
| 2060 | chd_error err; |
| 2061 | |
| 2062 | /* track the max */ |
| 2063 | if (hunknum > chd->maxhunk) |
| 2064 | chd->maxhunk = hunknum; |
| 2065 | |
| 2066 | /* if we're already in the cache, we're done */ |
| 2067 | if (chd->cachehunk == hunknum) |
| 2068 | return CHDERR_NONE; |
| 2069 | chd->cachehunk = ~0; |
| 2070 | |
| 2071 | /* otherwise, read the data */ |
| 2072 | err = hunk_read_into_memory(chd, hunknum, chd->cache); |
| 2073 | if (err != CHDERR_NONE) |
| 2074 | return err; |
| 2075 | |
| 2076 | /* mark the hunk successfully cached in */ |
| 2077 | chd->cachehunk = hunknum; |
| 2078 | return CHDERR_NONE; |
| 2079 | } |
| 2080 | |
| 2081 | /*------------------------------------------------- |
| 2082 | hunk_read_into_memory - read a hunk into |
| 2083 | memory at the given location |
| 2084 | -------------------------------------------------*/ |
| 2085 | |
| 2086 | static chd_error hunk_read_into_memory(chd_file *chd, UINT32 hunknum, UINT8 *dest) |
| 2087 | { |
| 2088 | chd_error err; |
| 2089 | |
| 2090 | /* punt if no file */ |
| 2091 | if (chd->file == NULL) |
| 2092 | return CHDERR_INVALID_FILE; |
| 2093 | |
| 2094 | /* return an error if out of range */ |
| 2095 | if (hunknum >= chd->header.totalhunks) |
| 2096 | return CHDERR_HUNK_OUT_OF_RANGE; |
| 2097 | |
| 2098 | if (chd->header.version < 5) |
| 2099 | { |
| 2100 | map_entry *entry = &chd->map[hunknum]; |
| 2101 | UINT32 bytes; |
| 2102 | UINT8* compressed_bytes; |
| 2103 | |
| 2104 | /* switch off the entry type */ |
| 2105 | switch (entry->flags & MAP_ENTRY_FLAG_TYPE_MASK) |
| 2106 | { |
| 2107 | /* compressed data */ |
| 2108 | case V34_MAP_ENTRY_TYPE_COMPRESSED: |
| 2109 | |
| 2110 | /* read it into the decompression buffer */ |
| 2111 | compressed_bytes = hunk_read_compressed(chd, entry->offset, entry->length); |
| 2112 | if (compressed_bytes == NULL) |
| 2113 | return CHDERR_READ_ERROR; |
| 2114 | |
| 2115 | /* now decompress using the codec */ |
| 2116 | err = CHDERR_NONE; |
| 2117 | void* codec = &chd->zlib_codec_data; |
| 2118 | if (chd->codecintf[0]->decompress != NULL) |
| 2119 | err = (*chd->codecintf[0]->decompress)(codec, compressed_bytes, entry->length, dest, chd->header.hunkbytes); |
| 2120 | if (err != CHDERR_NONE) |
| 2121 | return err; |
| 2122 | break; |
| 2123 | |
| 2124 | /* uncompressed data */ |
| 2125 | case V34_MAP_ENTRY_TYPE_UNCOMPRESSED: |
| 2126 | err = hunk_read_uncompressed(chd, entry->offset, chd->header.hunkbytes, dest); |
| 2127 | if (err != CHDERR_NONE) |
| 2128 | return err; |
| 2129 | break; |
| 2130 | |
| 2131 | /* mini-compressed data */ |
| 2132 | case V34_MAP_ENTRY_TYPE_MINI: |
| 2133 | put_bigendian_uint64(&dest[0], entry->offset); |
| 2134 | for (bytes = 8; bytes < chd->header.hunkbytes; bytes++) |
| 2135 | dest[bytes] = dest[bytes - 8]; |
| 2136 | break; |
| 2137 | |
| 2138 | /* self-referenced data */ |
| 2139 | case V34_MAP_ENTRY_TYPE_SELF_HUNK: |
| 2140 | if (chd->cachehunk == entry->offset && dest == chd->cache) |
| 2141 | break; |
| 2142 | return hunk_read_into_memory(chd, entry->offset, dest); |
| 2143 | |
| 2144 | /* parent-referenced data */ |
| 2145 | case V34_MAP_ENTRY_TYPE_PARENT_HUNK: |
| 2146 | err = hunk_read_into_memory(chd->parent, entry->offset, dest); |
| 2147 | if (err != CHDERR_NONE) |
| 2148 | return err; |
| 2149 | break; |
| 2150 | } |
| 2151 | return CHDERR_NONE; |
| 2152 | } |
| 2153 | else |
| 2154 | { |
| 2155 | /* get a pointer to the map entry */ |
| 2156 | uint64_t blockoffs; |
| 2157 | uint32_t blocklen; |
| 2158 | uint16_t blockcrc; |
| 2159 | uint8_t *rawmap = &chd->header.rawmap[chd->header.mapentrybytes * hunknum]; |
| 2160 | UINT8* compressed_bytes; |
| 2161 | |
| 2162 | /* uncompressed case */ |
| 2163 | if (!compressed(&chd->header)) |
| 2164 | { |
| 2165 | blockoffs = (uint64_t)get_bigendian_uint32(rawmap) * (uint64_t)chd->header.hunkbytes; |
| 2166 | if (blockoffs != 0) { |
| 2167 | core_fseek(chd->file, blockoffs, SEEK_SET); |
| 2168 | core_fread(chd->file, dest, chd->header.hunkbytes); |
| 2169 | /* TODO |
| 2170 | else if (m_parent_missing) |
| 2171 | throw CHDERR_REQUIRES_PARENT; */ |
| 2172 | } else if (chd->parent) { |
| 2173 | err = hunk_read_into_memory(chd->parent, hunknum, dest); |
| 2174 | if (err != CHDERR_NONE) |
| 2175 | return err; |
| 2176 | } else { |
| 2177 | memset(dest, 0, chd->header.hunkbytes); |
| 2178 | } |
| 2179 | } |
| 2180 | |
| 2181 | /* compressed case */ |
| 2182 | blocklen = get_bigendian_uint24(&rawmap[1]); |
| 2183 | blockoffs = get_bigendian_uint48(&rawmap[4]); |
| 2184 | blockcrc = get_bigendian_uint16(&rawmap[10]); |
| 2185 | void* codec = NULL; |
| 2186 | switch (rawmap[0]) |
| 2187 | { |
| 2188 | case COMPRESSION_TYPE_0: |
| 2189 | case COMPRESSION_TYPE_1: |
| 2190 | case COMPRESSION_TYPE_2: |
| 2191 | case COMPRESSION_TYPE_3: |
| 2192 | compressed_bytes = hunk_read_compressed(chd, blockoffs, blocklen); |
| 2193 | if (compressed_bytes == NULL) |
| 2194 | return CHDERR_READ_ERROR; |
| 2195 | switch (chd->codecintf[rawmap[0]]->compression) |
| 2196 | { |
| 2197 | case CHD_CODEC_CD_LZMA: |
| 2198 | codec = &chd->cdlz_codec_data; |
| 2199 | break; |
| 2200 | |
| 2201 | case CHD_CODEC_ZLIB: |
| 2202 | codec = &chd->zlib_codec_data; |
| 2203 | break; |
| 2204 | |
| 2205 | case CHD_CODEC_CD_ZLIB: |
| 2206 | codec = &chd->cdzl_codec_data; |
| 2207 | break; |
| 2208 | |
| 2209 | case CHD_CODEC_CD_FLAC: |
| 2210 | codec = &chd->cdfl_codec_data; |
| 2211 | break; |
| 2212 | } |
| 2213 | if (codec==NULL) |
| 2214 | return CHDERR_DECOMPRESSION_ERROR; |
| 2215 | chd->codecintf[rawmap[0]]->decompress(codec, compressed_bytes, blocklen, dest, chd->header.hunkbytes); |
| 2216 | if (dest != NULL && crc16(dest, chd->header.hunkbytes) != blockcrc) |
| 2217 | return CHDERR_DECOMPRESSION_ERROR; |
| 2218 | return CHDERR_NONE; |
| 2219 | |
| 2220 | case COMPRESSION_NONE: |
| 2221 | err = hunk_read_uncompressed(chd, blockoffs, blocklen, dest); |
| 2222 | if (err != CHDERR_NONE) |
| 2223 | return err; |
| 2224 | if (crc16(dest, chd->header.hunkbytes) != blockcrc) |
| 2225 | return CHDERR_DECOMPRESSION_ERROR; |
| 2226 | return CHDERR_NONE; |
| 2227 | |
| 2228 | case COMPRESSION_SELF: |
| 2229 | return hunk_read_into_memory(chd, blockoffs, dest); |
| 2230 | |
| 2231 | case COMPRESSION_PARENT: |
| 2232 | #if 0 |
| 2233 | /* TODO */ |
| 2234 | if (m_parent_missing) |
| 2235 | return CHDERR_REQUIRES_PARENT; |
| 2236 | return m_parent->read_bytes(uint64_t(blockoffs) * uint64_t(m_parent->unit_bytes()), dest, m_hunkbytes); |
| 2237 | #endif |
| 2238 | return CHDERR_DECOMPRESSION_ERROR; |
| 2239 | } |
| 2240 | return CHDERR_NONE; |
| 2241 | } |
| 2242 | |
| 2243 | /* We should not reach this code */ |
| 2244 | return CHDERR_DECOMPRESSION_ERROR; |
| 2245 | } |
| 2246 | |
| 2247 | /*************************************************************************** |
| 2248 | INTERNAL MAP ACCESS |
| 2249 | ***************************************************************************/ |
| 2250 | |
| 2251 | /*------------------------------------------------- |
| 2252 | map_read - read the initial sector map |
| 2253 | -------------------------------------------------*/ |
| 2254 | |
| 2255 | static chd_error map_read(chd_file *chd) |
| 2256 | { |
| 2257 | UINT32 entrysize = (chd->header.version < 3) ? OLD_MAP_ENTRY_SIZE : MAP_ENTRY_SIZE; |
| 2258 | UINT8 raw_map_entries[MAP_STACK_ENTRIES * MAP_ENTRY_SIZE]; |
| 2259 | UINT64 fileoffset, maxoffset = 0; |
| 2260 | UINT8 cookie[MAP_ENTRY_SIZE]; |
| 2261 | UINT32 count; |
| 2262 | chd_error err; |
| 2263 | int i; |
| 2264 | |
| 2265 | /* first allocate memory */ |
| 2266 | chd->map = (map_entry *)malloc(sizeof(chd->map[0]) * chd->header.totalhunks); |
| 2267 | if (!chd->map) |
| 2268 | return CHDERR_OUT_OF_MEMORY; |
| 2269 | |
| 2270 | /* read the map entries in in chunks and extract to the map list */ |
| 2271 | fileoffset = chd->header.length; |
| 2272 | for (i = 0; i < chd->header.totalhunks; i += MAP_STACK_ENTRIES) |
| 2273 | { |
| 2274 | /* compute how many entries this time */ |
| 2275 | int entries = chd->header.totalhunks - i, j; |
| 2276 | if (entries > MAP_STACK_ENTRIES) |
| 2277 | entries = MAP_STACK_ENTRIES; |
| 2278 | |
| 2279 | /* read that many */ |
| 2280 | core_fseek(chd->file, fileoffset, SEEK_SET); |
| 2281 | count = core_fread(chd->file, raw_map_entries, entries * entrysize); |
| 2282 | if (count != entries * entrysize) |
| 2283 | { |
| 2284 | err = CHDERR_READ_ERROR; |
| 2285 | goto cleanup; |
| 2286 | } |
| 2287 | fileoffset += entries * entrysize; |
| 2288 | |
| 2289 | /* process that many */ |
| 2290 | if (entrysize == MAP_ENTRY_SIZE) |
| 2291 | { |
| 2292 | for (j = 0; j < entries; j++) |
| 2293 | map_extract(&raw_map_entries[j * MAP_ENTRY_SIZE], &chd->map[i + j]); |
| 2294 | } |
| 2295 | else |
| 2296 | { |
| 2297 | for (j = 0; j < entries; j++) |
| 2298 | map_extract_old(&raw_map_entries[j * OLD_MAP_ENTRY_SIZE], &chd->map[i + j], chd->header.hunkbytes); |
| 2299 | } |
| 2300 | |
| 2301 | /* track the maximum offset */ |
| 2302 | for (j = 0; j < entries; j++) |
| 2303 | if ((chd->map[i + j].flags & MAP_ENTRY_FLAG_TYPE_MASK) == V34_MAP_ENTRY_TYPE_COMPRESSED || |
| 2304 | (chd->map[i + j].flags & MAP_ENTRY_FLAG_TYPE_MASK) == V34_MAP_ENTRY_TYPE_UNCOMPRESSED) |
| 2305 | maxoffset = MAX(maxoffset, chd->map[i + j].offset + chd->map[i + j].length); |
| 2306 | } |
| 2307 | |
| 2308 | /* verify the cookie */ |
| 2309 | core_fseek(chd->file, fileoffset, SEEK_SET); |
| 2310 | count = core_fread(chd->file, &cookie, entrysize); |
| 2311 | if (count != entrysize || memcmp(&cookie, END_OF_LIST_COOKIE, entrysize)) |
| 2312 | { |
| 2313 | err = CHDERR_INVALID_FILE; |
| 2314 | goto cleanup; |
| 2315 | } |
| 2316 | |
| 2317 | /* verify the length */ |
| 2318 | if (maxoffset > core_fsize(chd->file)) |
| 2319 | { |
| 2320 | err = CHDERR_INVALID_FILE; |
| 2321 | goto cleanup; |
| 2322 | } |
| 2323 | return CHDERR_NONE; |
| 2324 | |
| 2325 | cleanup: |
| 2326 | if (chd->map) |
| 2327 | free(chd->map); |
| 2328 | chd->map = NULL; |
| 2329 | return err; |
| 2330 | } |
| 2331 | |
| 2332 | /*************************************************************************** |
| 2333 | INTERNAL METADATA ACCESS |
| 2334 | ***************************************************************************/ |
| 2335 | |
| 2336 | /*------------------------------------------------- |
| 2337 | metadata_find_entry - find a metadata entry |
| 2338 | -------------------------------------------------*/ |
| 2339 | |
| 2340 | static chd_error metadata_find_entry(chd_file *chd, UINT32 metatag, UINT32 metaindex, metadata_entry *metaentry) |
| 2341 | { |
| 2342 | /* start at the beginning */ |
| 2343 | metaentry->offset = chd->header.metaoffset; |
| 2344 | metaentry->prev = 0; |
| 2345 | |
| 2346 | /* loop until we run out of options */ |
| 2347 | while (metaentry->offset != 0) |
| 2348 | { |
| 2349 | UINT8 raw_meta_header[METADATA_HEADER_SIZE]; |
| 2350 | UINT32 count; |
| 2351 | |
| 2352 | /* read the raw header */ |
| 2353 | core_fseek(chd->file, metaentry->offset, SEEK_SET); |
| 2354 | count = core_fread(chd->file, raw_meta_header, sizeof(raw_meta_header)); |
| 2355 | if (count != sizeof(raw_meta_header)) |
| 2356 | break; |
| 2357 | |
| 2358 | /* extract the data */ |
| 2359 | metaentry->metatag = get_bigendian_uint32(&raw_meta_header[0]); |
| 2360 | metaentry->length = get_bigendian_uint32(&raw_meta_header[4]); |
| 2361 | metaentry->next = get_bigendian_uint64(&raw_meta_header[8]); |
| 2362 | |
| 2363 | /* flags are encoded in the high byte of length */ |
| 2364 | metaentry->flags = metaentry->length >> 24; |
| 2365 | metaentry->length &= 0x00ffffff; |
| 2366 | |
| 2367 | /* if we got a match, proceed */ |
| 2368 | if (metatag == CHDMETATAG_WILDCARD || metaentry->metatag == metatag) |
| 2369 | if (metaindex-- == 0) |
| 2370 | return CHDERR_NONE; |
| 2371 | |
| 2372 | /* no match, fetch the next link */ |
| 2373 | metaentry->prev = metaentry->offset; |
| 2374 | metaentry->offset = metaentry->next; |
| 2375 | } |
| 2376 | |
| 2377 | /* if we get here, we didn't find it */ |
| 2378 | return CHDERR_METADATA_NOT_FOUND; |
| 2379 | } |
| 2380 | |
| 2381 | /*************************************************************************** |
| 2382 | ZLIB COMPRESSION CODEC |
| 2383 | ***************************************************************************/ |
| 2384 | |
| 2385 | /*------------------------------------------------- |
| 2386 | zlib_codec_init - initialize the ZLIB codec |
| 2387 | -------------------------------------------------*/ |
| 2388 | |
| 2389 | static chd_error zlib_codec_init(void *codec, uint32_t hunkbytes) |
| 2390 | { |
| 2391 | zlib_codec_data *data = (zlib_codec_data*)codec; |
| 2392 | chd_error err; |
| 2393 | int zerr; |
| 2394 | |
| 2395 | /* clear the buffers */ |
| 2396 | memset(data, 0, sizeof(zlib_codec_data)); |
| 2397 | |
| 2398 | /* init the inflater first */ |
| 2399 | data->inflater.next_in = (Bytef *)data; /* bogus, but that's ok */ |
| 2400 | data->inflater.avail_in = 0; |
| 2401 | data->inflater.zalloc = zlib_fast_alloc; |
| 2402 | data->inflater.zfree = zlib_fast_free; |
| 2403 | data->inflater.opaque = &data->allocator; |
| 2404 | zerr = inflateInit2(&data->inflater, -MAX_WBITS); |
| 2405 | |
| 2406 | /* convert errors */ |
| 2407 | if (zerr == Z_MEM_ERROR) |
| 2408 | err = CHDERR_OUT_OF_MEMORY; |
| 2409 | else if (zerr != Z_OK) |
| 2410 | err = CHDERR_CODEC_ERROR; |
| 2411 | else |
| 2412 | err = CHDERR_NONE; |
| 2413 | |
| 2414 | /* handle an error */ |
| 2415 | if (err != CHDERR_NONE) |
| 2416 | free(data); |
| 2417 | |
| 2418 | return err; |
| 2419 | } |
| 2420 | |
| 2421 | /*------------------------------------------------- |
| 2422 | zlib_codec_free - free data for the ZLIB |
| 2423 | codec |
| 2424 | -------------------------------------------------*/ |
| 2425 | |
| 2426 | static void zlib_codec_free(void *codec) |
| 2427 | { |
| 2428 | zlib_codec_data *data = (zlib_codec_data *)codec; |
| 2429 | |
| 2430 | /* deinit the streams */ |
| 2431 | if (data != NULL) |
| 2432 | { |
| 2433 | int i; |
| 2434 | |
| 2435 | inflateEnd(&data->inflater); |
| 2436 | |
| 2437 | /* free our fast memory */ |
| 2438 | zlib_allocator alloc = data->allocator; |
| 2439 | for (i = 0; i < MAX_ZLIB_ALLOCS; i++) |
| 2440 | if (alloc.allocptr[i]) |
| 2441 | free(alloc.allocptr[i]); |
| 2442 | } |
| 2443 | } |
| 2444 | |
| 2445 | /*------------------------------------------------- |
| 2446 | zlib_codec_decompress - decomrpess data using |
| 2447 | the ZLIB codec |
| 2448 | -------------------------------------------------*/ |
| 2449 | |
| 2450 | static chd_error zlib_codec_decompress(void *codec, const uint8_t *src, uint32_t complen, uint8_t *dest, uint32_t destlen) |
| 2451 | { |
| 2452 | zlib_codec_data *data = (zlib_codec_data *)codec; |
| 2453 | int zerr; |
| 2454 | |
| 2455 | /* reset the decompressor */ |
| 2456 | data->inflater.next_in = (Bytef *)src; |
| 2457 | data->inflater.avail_in = complen; |
| 2458 | data->inflater.total_in = 0; |
| 2459 | data->inflater.next_out = (Bytef *)dest; |
| 2460 | data->inflater.avail_out = destlen; |
| 2461 | data->inflater.total_out = 0; |
| 2462 | zerr = inflateReset(&data->inflater); |
| 2463 | if (zerr != Z_OK) |
| 2464 | return CHDERR_DECOMPRESSION_ERROR; |
| 2465 | |
| 2466 | /* do it */ |
| 2467 | zerr = inflate(&data->inflater, Z_FINISH); |
| 2468 | if (data->inflater.total_out != destlen) |
| 2469 | return CHDERR_DECOMPRESSION_ERROR; |
| 2470 | |
| 2471 | return CHDERR_NONE; |
| 2472 | } |
| 2473 | |
| 2474 | /*------------------------------------------------- |
| 2475 | zlib_fast_alloc - fast malloc for ZLIB, which |
| 2476 | allocates and frees memory frequently |
| 2477 | -------------------------------------------------*/ |
| 2478 | |
| 2479 | static voidpf zlib_fast_alloc(voidpf opaque, uInt items, uInt size) |
| 2480 | { |
| 2481 | zlib_allocator *alloc = (zlib_allocator *)opaque; |
| 2482 | UINT32 *ptr; |
| 2483 | int i; |
| 2484 | |
| 2485 | /* compute the size, rounding to the nearest 1k */ |
| 2486 | size = (size * items + 0x3ff) & ~0x3ff; |
| 2487 | |
| 2488 | /* reuse a hunk if we can */ |
| 2489 | for (i = 0; i < MAX_ZLIB_ALLOCS; i++) |
| 2490 | { |
| 2491 | ptr = alloc->allocptr[i]; |
| 2492 | if (ptr && size == *ptr) |
| 2493 | { |
| 2494 | /* set the low bit of the size so we don't match next time */ |
| 2495 | *ptr |= 1; |
| 2496 | return ptr + 1; |
| 2497 | } |
| 2498 | } |
| 2499 | |
| 2500 | /* alloc a new one */ |
| 2501 | ptr = (UINT32 *)malloc(size + sizeof(uintptr_t)); |
| 2502 | if (!ptr) |
| 2503 | return NULL; |
| 2504 | |
| 2505 | /* put it into the list */ |
| 2506 | for (i = 0; i < MAX_ZLIB_ALLOCS; i++) |
| 2507 | if (!alloc->allocptr[i]) |
| 2508 | { |
| 2509 | alloc->allocptr[i] = ptr; |
| 2510 | break; |
| 2511 | } |
| 2512 | |
| 2513 | /* set the low bit of the size so we don't match next time */ |
| 2514 | *ptr = size | 1; |
| 2515 | return ptr + (sizeof(uint32_t) == sizeof(uintptr_t) ? 1 : 2); |
| 2516 | } |
| 2517 | |
| 2518 | /*------------------------------------------------- |
| 2519 | zlib_fast_free - fast free for ZLIB, which |
| 2520 | allocates and frees memory frequently |
| 2521 | -------------------------------------------------*/ |
| 2522 | |
| 2523 | static void zlib_fast_free(voidpf opaque, voidpf address) |
| 2524 | { |
| 2525 | zlib_allocator *alloc = (zlib_allocator *)opaque; |
| 2526 | UINT32 *ptr = (UINT32 *)address - (sizeof(uint32_t) == sizeof(uintptr_t) ? 1 : 2); |
| 2527 | int i; |
| 2528 | |
| 2529 | /* find the hunk */ |
| 2530 | for (i = 0; i < MAX_ZLIB_ALLOCS; i++) |
| 2531 | if (ptr == alloc->allocptr[i]) |
| 2532 | { |
| 2533 | /* clear the low bit of the size to allow matches */ |
| 2534 | *ptr &= ~1; |
| 2535 | return; |
| 2536 | } |
| 2537 | } |