page0zip.c 102 KB
Newer Older
marko's avatar
marko committed
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
/******************************************************
Compressed page interface

(c) 2005 Innobase Oy

Created June 2005 by Marko Makela
*******************************************************/

#define THIS_MODULE
#include "page0zip.h"
#ifdef UNIV_NONINL
# include "page0zip.ic"
#endif
#undef THIS_MODULE
#include "page0page.h"
#include "mtr0log.h"
17
#include "ut0sort.h"
18
#include "dict0boot.h"
19
#include "dict0dict.h"
20
#include "btr0sea.h"
21 22
#include "btr0cur.h"
#include "page0types.h"
23
#include "lock0lock.h"
24
#include "log0recv.h"
marko's avatar
marko committed
25 26
#include "zlib.h"

27 28 29
/* Please refer to ../include/page0zip.ic for a description of the
compressed page format. */

30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49
/* The infimum and supremum records are omitted from the compressed page.
On compress, we compare that the records are there, and on uncompress we
restore the records. */
static const byte infimum_extra[] = {
	0x01,			/* info_bits=0, n_owned=1 */
	0x00, 0x02		/* heap_no=0, status=2 */
	/* ?, ?	*/		/* next=(first user rec, or supremum) */
};
static const byte infimum_data[] = {
	0x69, 0x6e, 0x66, 0x69,
	0x6d, 0x75, 0x6d, 0x00	/* "infimum\0" */
};
static const byte supremum_extra_data[] = {
	/* 0x0?, */		/* info_bits=0, n_owned=1..8 */
	0x00, 0x0b,		/* heap_no=1, status=3 */
	0x00, 0x00,		/* next=0 */
	0x73, 0x75, 0x70, 0x72,
	0x65, 0x6d, 0x75, 0x6d	/* "supremum" */
};

marko's avatar
marko committed
50 51 52 53 54
#ifdef UNIV_DEBUG
/* Array of zeros, used for debug assertions */
static const byte zero[BTR_EXTERN_FIELD_REF_SIZE] = { 0, };
#endif

55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78
/**************************************************************************
Determine the guaranteed free space on an empty page. */

ulint
page_zip_empty_size(
/*================*/
				/* out: minimum payload size on the page */
	ulint	n_fields,	/* in: number of columns in the index */
	ulint	zip_size)	/* in: compressed page size in bytes */
{
	lint	size = zip_size
		/* subtract the page header and the longest
		uncompressed data needed for one record */
		- (PAGE_DATA
		   + PAGE_ZIP_DIR_SLOT_SIZE
		   + DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN
		   + 1/* encoded heap_no==2 in page_zip_write_rec() */
		   + 1/* end of modification log */
		   - REC_N_NEW_EXTRA_BYTES/* omitted bytes */)
		/* subtract the space for page_zip_fields_encode() */
		- compressBound(2 * (n_fields + 1));
	return(size > 0 ? (ulint) size : 0);
}

79 80 81 82 83 84 85 86 87 88 89 90 91
/*****************************************************************
Gets the size of the compressed page trailer (the dense page directory),
including deleted records (the free list). */
UNIV_INLINE
ulint
page_zip_dir_size(
/*==============*/
						/* out: length of dense page
						directory, in bytes */
	const page_zip_des_t*	page_zip)	/* in: compressed page */
{
	/* Exclude the page infimum and supremum from the record count. */
	ulint	size = PAGE_ZIP_DIR_SLOT_SIZE
92 93
		* (page_dir_get_n_heap(page_zip->data)
		   - PAGE_HEAP_NO_USER_LOW);
94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109
	return(size);
}

/*****************************************************************
Gets the size of the compressed page trailer (the dense page directory),
only including user records (excluding the free list). */
UNIV_INLINE
ulint
page_zip_dir_user_size(
/*===================*/
						/* out: length of dense page
						directory comprising existing
						records, in bytes */
	const page_zip_des_t*	page_zip)	/* in: compressed page */
{
	ulint	size = PAGE_ZIP_DIR_SLOT_SIZE
110
		* page_get_n_recs(page_zip->data);
111
	ut_ad(size <= page_zip_dir_size(page_zip));
112 113 114 115
	return(size);
}

/*****************************************************************
116
Find the slot of the given record in the dense page directory. */
117 118
UNIV_INLINE
byte*
119 120 121 122 123 124 125
page_zip_dir_find_low(
/*==================*/
					/* out: dense directory slot,
					or NULL if record not found */
	byte*	slot,			/* in: start of records */
	byte*	end,			/* in: end of records */
	ulint	offset)			/* in: offset of user record */
126
{
127
	ut_ad(slot <= end);
128 129 130

	for (; slot < end; slot += PAGE_ZIP_DIR_SLOT_SIZE) {
		if ((mach_read_from_2(slot) & PAGE_ZIP_DIR_SLOT_MASK)
131
		    == offset) {
132 133 134 135 136 137 138 139
			return(slot);
		}
	}

	return(NULL);
}

/*****************************************************************
140
Find the slot of the given non-free record in the dense page directory. */
141 142
UNIV_INLINE
byte*
143 144 145 146 147 148
page_zip_dir_find(
/*==============*/
						/* out: dense directory slot,
						or NULL if record not found */
	page_zip_des_t*	page_zip,		/* in: compressed page */
	ulint		offset)			/* in: offset of user record */
149
{
150
	byte*	end	= page_zip->data + page_zip_get_size(page_zip);
151

152
	ut_ad(page_zip_simple_validate(page_zip));
153

154 155 156
	return(page_zip_dir_find_low(end - page_zip_dir_user_size(page_zip),
				     end,
				     offset));
157 158
}

159 160 161 162 163 164 165 166 167 168 169
/*****************************************************************
Find the slot of the given free record in the dense page directory. */
UNIV_INLINE
byte*
page_zip_dir_find_free(
/*===================*/
						/* out: dense directory slot,
						or NULL if record not found */
	page_zip_des_t*	page_zip,		/* in: compressed page */
	ulint		offset)			/* in: offset of user record */
{
170
	byte*	end	= page_zip->data + page_zip_get_size(page_zip);
171 172 173

	ut_ad(page_zip_simple_validate(page_zip));

174 175 176
	return(page_zip_dir_find_low(end - page_zip_dir_size(page_zip),
				     end - page_zip_dir_user_size(page_zip),
				     offset));
177 178
}

179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195
/*****************************************************************
Read a given slot in the dense page directory. */
UNIV_INLINE
ulint
page_zip_dir_get(
/*=============*/
						/* out: record offset
						on the uncompressed page,
						possibly ORed with
						PAGE_ZIP_DIR_SLOT_DEL or
						PAGE_ZIP_DIR_SLOT_OWNED */
	const page_zip_des_t*	page_zip,	/* in: compressed page */
	ulint			slot)		/* in: slot
						(0=first user record) */
{
	ut_ad(page_zip_simple_validate(page_zip));
	ut_ad(slot < page_zip_dir_size(page_zip) / PAGE_ZIP_DIR_SLOT_SIZE);
196
	return(mach_read_from_2(page_zip->data + page_zip_get_size(page_zip)
197
				- PAGE_ZIP_DIR_SLOT_SIZE * (slot + 1)));
198 199
}

200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220
/**************************************************************************
Write a log record of compressing an index page. */
static
void
page_zip_compress_write_log(
/*========================*/
	const page_zip_des_t*	page_zip,/* in: compressed page */
	const page_t*		page,	/* in: uncompressed page */
	dict_index_t*		index,	/* in: index of the B-tree node */
	mtr_t*			mtr)	/* in: mini-transaction */
{
	byte*	log_ptr;
	ulint	trailer_size;

	log_ptr = mlog_open(mtr, 11 + 2 + 2);

	if (!log_ptr) {

		return;
	}

221 222 223
	/* Read the number of user records. */
	trailer_size = page_dir_get_n_heap(page_zip->data)
		- PAGE_HEAP_NO_USER_LOW;
224
	/* Multiply by uncompressed of size stored per record */
225
	if (!page_is_leaf(page)) {
226
		trailer_size *= PAGE_ZIP_DIR_SLOT_SIZE + REC_NODE_PTR_SIZE;
227 228
	} else if (dict_index_is_clust(index)) {
		trailer_size *= PAGE_ZIP_DIR_SLOT_SIZE
229
			+ DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN;
230 231
	} else {
		trailer_size *= PAGE_ZIP_DIR_SLOT_SIZE;
232 233 234 235 236 237 238
	}
	/* Add the space occupied by BLOB pointers. */
	trailer_size += page_zip->n_blobs * BTR_EXTERN_FIELD_REF_SIZE;
	ut_a(page_zip->m_end > PAGE_DATA);
#if FIL_PAGE_DATA > PAGE_DATA
# error "FIL_PAGE_DATA > PAGE_DATA"
#endif
239
	ut_a(page_zip->m_end + trailer_size <= page_zip_get_size(page_zip));
240

241 242 243
	log_ptr = mlog_write_initial_log_record_fast((page_t*) page,
						     MLOG_ZIP_PAGE_COMPRESS,
						     log_ptr, mtr);
244 245 246 247 248 249 250 251 252 253 254 255
	mach_write_to_2(log_ptr, page_zip->m_end - FIL_PAGE_TYPE);
	log_ptr += 2;
	mach_write_to_2(log_ptr, trailer_size);
	log_ptr += 2;
	mlog_close(mtr, log_ptr);

	/* Write FIL_PAGE_PREV and FIL_PAGE_NEXT */
	mlog_catenate_string(mtr, page_zip->data + FIL_PAGE_PREV, 4);
	mlog_catenate_string(mtr, page_zip->data + FIL_PAGE_NEXT, 4);
	/* Write most of the page header, the compressed stream and
	the modification log. */
	mlog_catenate_string(mtr, page_zip->data + FIL_PAGE_TYPE,
256
			     page_zip->m_end - FIL_PAGE_TYPE);
257
	/* Write the uncompressed trailer of the compressed page. */
258
	mlog_catenate_string(mtr, page_zip->data + page_zip_get_size(page_zip)
259
			     - trailer_size, trailer_size);
260 261
}

262 263
/**********************************************************
Determine how many externally stored columns are contained
264
in existing records with smaller heap_no than rec. */
265
static
266 267 268
ulint
page_zip_get_n_prev_extern(
/*=======================*/
269 270 271 272 273
	const page_zip_des_t*	page_zip,/* in: dense page directory on
					compressed page */
	const rec_t*		rec,	/* in: compact physical record
					on a B-tree leaf page */
	dict_index_t*		index)	/* in: record descriptor */
274
{
275 276 277 278 279 280
	const page_t*	page	= page_align((rec_t*) rec);
	ulint		n_ext	= 0;
	ulint		i;
	ulint		left;
	ulint		heap_no;
	ulint		n_recs	= page_get_n_recs(page_zip->data);
281 282 283 284

	ut_ad(page_is_leaf(page));
	ut_ad(page_is_comp(page));
	ut_ad(dict_table_is_comp(index->table));
285
	ut_ad(dict_index_is_clust(index));
286

287
	heap_no = rec_get_heap_no_new(rec);
288 289
	ut_ad(heap_no >= PAGE_HEAP_NO_USER_LOW);
	left = heap_no - PAGE_HEAP_NO_USER_LOW;
290 291 292
	if (UNIV_UNLIKELY(!left)) {
		return(0);
	}
293

294
	for (i = 0; i < n_recs; i++) {
295 296
		const rec_t*	r	= page + (page_zip_dir_get(page_zip, i)
						  & PAGE_ZIP_DIR_SLOT_MASK);
297

298
		if (rec_get_heap_no_new(r) < heap_no) {
299 300
			n_ext += rec_get_n_extern_new(r, index,
						      ULINT_UNDEFINED);
301 302 303
			if (!--left) {
				break;
			}
304
		}
305
	}
306

307
	return(n_ext);
308 309
}

310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330
/**************************************************************************
Encode the length of a fixed-length column. */
static
byte*
page_zip_fixed_field_encode(
/*========================*/
			/* out: buf + length of encoded val */
	byte*	buf,	/* in: pointer to buffer where to write */
	ulint	val)	/* in: value to write */
{
	ut_ad(val >= 2);

	if (UNIV_LIKELY(val < 126)) {
		/*
		0 = nullable variable field of at most 255 bytes length;
		1 = not null variable field of at most 255 bytes length;
		126 = nullable variable field with maximum length >255;
		127 = not null variable field with maximum length >255
		*/
		*buf++ = val;
	} else {
331
		*buf++ = 0x80 | val >> 8;
332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364
		*buf++ = 0xff & val;
	}

	return(buf);
}

/**************************************************************************
Write the index information for the compressed page. */
static
ulint
page_zip_fields_encode(
/*===================*/
				/* out: used size of buf */
	ulint		n,	/* in: number of fields to compress */
	dict_index_t*	index,	/* in: index comprising at least n fields */
	ulint		trx_id_pos,/* in: position of the trx_id column
				in the index, or ULINT_UNDEFINED if
				this is a non-leaf page */
	byte*		buf)	/* out: buffer of (n + 1) * 2 bytes */
{
	const byte*	buf_start	= buf;
	ulint		i;
	ulint		col;
	ulint		trx_id_col	= 0;
	/* sum of lengths of preceding non-nullable fixed fields, or 0 */
	ulint		fixed_sum	= 0;

	ut_ad(trx_id_pos == ULINT_UNDEFINED || trx_id_pos < n);

	for (i = col = 0; i < n; i++) {
		dict_field_t*	field = dict_index_get_nth_field(index, i);
		ulint		val;

365
		if (dict_field_get_col(field)->prtype & DATA_NOT_NULL) {
366 367 368 369 370 371 372
			val = 1; /* set the "not nullable" flag */
		} else {
			val = 0; /* nullable field */
		}

		if (!field->fixed_len) {
			/* variable-length field */
373 374
			const dict_col_t*	column
				= dict_field_get_col(field);
375

376 377
			if (UNIV_UNLIKELY(column->len > 255)
			    || UNIV_UNLIKELY(column->mtype == DATA_BLOB)) {
378 379 380 381 382 383
				val |= 0x7e; /* max > 255 bytes */
			}

			if (fixed_sum) {
				/* write out the length of any
				preceding non-nullable fields */
384 385
				buf = page_zip_fixed_field_encode(
					buf, fixed_sum << 1 | 1);
386 387 388 389 390 391 392 393
				fixed_sum = 0;
				col++;
			}

			*buf++ = val;
			col++;
		} else if (val) {
			/* fixed-length non-nullable field */
394

395 396 397
			if (fixed_sum && UNIV_UNLIKELY
			    (fixed_sum + field->fixed_len
			     > DICT_MAX_INDEX_COL_LEN)) {
398 399 400 401
				/* Write out the length of the
				preceding non-nullable fields,
				to avoid exceeding the maximum
				length of a fixed-length column. */
402 403
				buf = page_zip_fixed_field_encode(
					buf, fixed_sum << 1 | 1);
404 405 406 407
				fixed_sum = 0;
				col++;
			}

408 409 410 411 412
			if (i && UNIV_UNLIKELY(i == trx_id_pos)) {
				if (fixed_sum) {
					/* Write out the length of any
					preceding non-nullable fields,
					and start a new trx_id column. */
413 414
					buf = page_zip_fixed_field_encode(
						buf, fixed_sum << 1 | 1);
415
					col++;
416 417
				}

418
				trx_id_col = col;
419 420 421 422 423 424 425 426 427 428 429
				fixed_sum = field->fixed_len;
			} else {
				/* add to the sum */
				fixed_sum += field->fixed_len;
			}
		} else {
			/* fixed-length nullable field */

			if (fixed_sum) {
				/* write out the length of any
				preceding non-nullable fields */
430 431
				buf = page_zip_fixed_field_encode(
					buf, fixed_sum << 1 | 1);
432 433 434 435
				fixed_sum = 0;
				col++;
			}

436 437
			buf = page_zip_fixed_field_encode(
				buf, field->fixed_len << 1);
438 439 440 441 442 443 444 445 446 447 448
			col++;
		}
	}

	if (fixed_sum) {
		/* Write out the lengths of last fixed-length columns. */
		buf = page_zip_fixed_field_encode(buf, fixed_sum << 1 | 1);
	}

	if (trx_id_pos != ULINT_UNDEFINED) {
		/* Write out the position of the trx_id column */
marko's avatar
marko committed
449 450 451 452
		i = trx_id_col;
	} else {
		/* Write out the number of nullable fields */
		i = index->n_nullable;
453 454
	}

marko's avatar
marko committed
455 456 457 458 459 460 461 462
	if (i < 128) {
		*buf++ = i;
	} else {
		*buf++ = 0x80 | i >> 8;
		*buf++ = 0xff & i;
	}

	ut_ad((ulint) (buf - buf_start) <= (n + 2) * 2);
463 464 465
	return((ulint) (buf - buf_start));
}

466 467 468 469 470 471 472
/**************************************************************************
Populate the dense page directory from the sparse directory. */
static
void
page_zip_dir_encode(
/*================*/
	const page_t*	page,	/* in: compact page */
473 474 475
	byte*		buf,	/* in: pointer to dense page directory[-1];
				out: dense directory on compressed page */
	const rec_t**	recs)	/* in: pointer to an array of 0, or NULL;
476 477
				out: dense page directory sorted by ascending
				address (and heap_no) */
478
{
479 480 481 482 483 484 485
	const byte*	rec;
	ulint		status;
	ulint		min_mark;
	ulint		heap_no;
	ulint		i;
	ulint		n_heap;
	ulint		offs;
486 487 488

	min_mark = 0;

489 490 491
	if (page_is_leaf(page)) {
		status = REC_STATUS_ORDINARY;
	} else {
492
		status = REC_STATUS_NODE_PTR;
493
		if (UNIV_UNLIKELY
494
		    (mach_read_from_4(page + FIL_PAGE_PREV) == FIL_NULL)) {
495 496 497 498
			min_mark = REC_INFO_MIN_REC_FLAG;
		}
	}

499
	n_heap = page_dir_get_n_heap(page);
500 501 502 503

	/* Traverse the list of stored records in the collation order,
	starting from the first user record. */

504
	rec = page + PAGE_NEW_INFIMUM, TRUE;
505 506 507 508 509 510 511 512 513

	i = 0;

	for (;;) {
		ulint	info_bits;
		offs = rec_get_next_offs(rec, TRUE);
		if (UNIV_UNLIKELY(offs == PAGE_NEW_SUPREMUM)) {
			break;
		}
514
		rec = page + offs;
515
		heap_no = rec_get_heap_no_new(rec);
516
		ut_a(heap_no >= PAGE_HEAP_NO_USER_LOW);
517
		ut_a(heap_no < n_heap);
518 519 520 521 522
		ut_a(offs < UNIV_PAGE_SIZE - PAGE_DIR);
		ut_a(offs >= PAGE_ZIP_START);
#if PAGE_ZIP_DIR_SLOT_MASK & UNIV_PAGE_SIZE
# error "PAGE_ZIP_DIR_SLOT_MASK & UNIV_PAGE_SIZE"
#endif
523 524 525 526 527 528 529 530 531 532 533 534 535 536
		if (UNIV_UNLIKELY(rec_get_n_owned_new(rec))) {
			offs |= PAGE_ZIP_DIR_SLOT_OWNED;
		}

		info_bits = rec_get_info_bits(rec, TRUE);
		if (UNIV_UNLIKELY(info_bits & REC_INFO_DELETED_FLAG)) {
			info_bits &= ~REC_INFO_DELETED_FLAG;
			offs |= PAGE_ZIP_DIR_SLOT_DEL;
		}
		ut_a(info_bits == min_mark);
		/* Only the smallest user record can have
		REC_INFO_MIN_REC_FLAG set. */
		min_mark = 0;

537
		mach_write_to_2(buf - PAGE_ZIP_DIR_SLOT_SIZE * ++i, offs);
538

539 540
		if (UNIV_LIKELY_NULL(recs)) {
			/* Ensure that each heap_no occurs at most once. */
541
			ut_a(!recs[heap_no - PAGE_HEAP_NO_USER_LOW]);
542
			/* exclude infimum and supremum */
543
			recs[heap_no - PAGE_HEAP_NO_USER_LOW] = rec;
544
		}
545 546 547 548

		ut_a(rec_get_status(rec) == status);
	}

549
	offs = page_header_get_field(page, PAGE_FREE);
550 551 552 553

	/* Traverse the free list (of deleted records). */
	while (offs) {
		ut_ad(!(offs & ~PAGE_ZIP_DIR_SLOT_MASK));
554
		rec = page + offs;
555 556

		heap_no = rec_get_heap_no_new(rec);
557
		ut_a(heap_no >= PAGE_HEAP_NO_USER_LOW);
558 559 560 561 562
		ut_a(heap_no < n_heap);

		ut_a(!rec[-REC_N_NEW_EXTRA_BYTES]); /* info_bits and n_owned */
		ut_a(rec_get_status(rec) == status);

563
		mach_write_to_2(buf - PAGE_ZIP_DIR_SLOT_SIZE * ++i, offs);
564

565 566
		if (UNIV_LIKELY_NULL(recs)) {
			/* Ensure that each heap_no occurs at most once. */
567
			ut_a(!recs[heap_no - PAGE_HEAP_NO_USER_LOW]);
568
			/* exclude infimum and supremum */
569
			recs[heap_no - PAGE_HEAP_NO_USER_LOW] = rec;
570
		}
571 572 573 574 575

		offs = rec_get_next_offs(rec, TRUE);
	}

	/* Ensure that each heap no occurs at least once. */
576
	ut_a(i + PAGE_HEAP_NO_USER_LOW == n_heap);
577 578
}

579 580 581 582
/**************************************************************************
Allocate memory for zlib. */
static
void*
583 584
page_zip_malloc(
/*============*/
585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600
	void*	opaque __attribute__((unused)),
	uInt	items,
	uInt	size)
{
	return(ut_malloc(items * size));
}

/**************************************************************************
Deallocate memory for zlib. */
static
void
page_zip_free(
/*==========*/
	 void*	opaque __attribute__((unused)),
	 void*	address)
{
601
	ut_free(address);
602 603
}

604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633
#if defined UNIV_DEBUG || defined UNIV_ZIP_DEBUG
/* Set this variable in a debugger to enable
excessive logging in page_zip_compress(). */
ibool	page_zip_compress_dbg;

/**************************************************************************
Wrapper for deflate().  Log the operation if page_zip_compress_dbg is set. */
static
ibool
page_zip_compress_deflate(
/*======================*/
	z_streamp	strm,	/* in/out: compressed stream for deflate() */
	int		flush)	/* in: deflate() flushing method */
{
	int	status;
	if (UNIV_UNLIKELY(page_zip_compress_dbg)) {
		ut_print_buf(stderr, strm->next_in, strm->avail_in);
	}
	status = deflate(strm, flush);
	if (UNIV_UNLIKELY(page_zip_compress_dbg)) {
		fprintf(stderr, " -> %d\n", status);
	}
	return(status);
}

/* Redefine deflate(). */
# undef deflate
# define deflate page_zip_compress_deflate
#endif /* UNIV_DEBUG || UNIV_ZIP_DEBUG */

634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652
/**************************************************************************
Compress the records of a node pointer page. */
static
int
page_zip_compress_node_ptrs(
/*========================*/
					/* out: Z_OK, or a zlib error code */
	z_stream*	c_stream,	/* in/out: compressed page stream */
	const rec_t**	recs,		/* in: dense page directory
					sorted by address */
	ulint		n_dense,	/* in: size of recs[] */
	dict_index_t*	index,		/* in: the index of the page */
	byte*		storage,	/* in: end of dense page directory */
	mem_heap_t*	heap)		/* in: temporary memory heap */
{
	int	err	= Z_OK;
	ulint*	offsets = NULL;

	do {
653
		const rec_t*	rec = *recs++;
654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672

		offsets = rec_get_offsets(rec, index, offsets,
					  ULINT_UNDEFINED, &heap);
		/* Only leaf nodes may contain externally stored columns. */
		ut_ad(!rec_offs_any_extern(offsets));

		/* Compress the extra bytes. */
		c_stream->avail_in = rec - REC_N_NEW_EXTRA_BYTES
			- c_stream->next_in;

		if (c_stream->avail_in) {
			err = deflate(c_stream, Z_NO_FLUSH);
			if (UNIV_UNLIKELY(err != Z_OK)) {
				break;
			}
		}
		ut_ad(!c_stream->avail_in);

		/* Compress the data bytes, except node_ptr. */
673
		c_stream->next_in = (byte*) rec;
674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763
		c_stream->avail_in = rec_offs_data_size(offsets)
			- REC_NODE_PTR_SIZE;
		ut_ad(c_stream->avail_in);

		err = deflate(c_stream, Z_NO_FLUSH);
		if (UNIV_UNLIKELY(err != Z_OK)) {
			break;
		}

		ut_ad(!c_stream->avail_in);

		memcpy(storage - REC_NODE_PTR_SIZE
		       * (rec_get_heap_no_new(rec) - 1),
		       c_stream->next_in, REC_NODE_PTR_SIZE);
		c_stream->next_in += REC_NODE_PTR_SIZE;
	} while (--n_dense);

	return(err);
}

/**************************************************************************
Compress the records of a leaf node of a secondary index. */
static
int
page_zip_compress_sec(
/*==================*/
					/* out: Z_OK, or a zlib error code */
	z_stream*	c_stream,	/* in/out: compressed page stream */
	const rec_t**	recs,		/* in: dense page directory
					sorted by address */
	ulint		n_dense)	/* in: size of recs[] */
{
	int		err	= Z_OK;

	ut_ad(n_dense > 0);

	do {
		const rec_t*	rec = *recs++;

		/* Compress everything up to this record. */
		c_stream->avail_in = rec - REC_N_NEW_EXTRA_BYTES
			- c_stream->next_in;

		if (UNIV_LIKELY(c_stream->avail_in)) {
			err = deflate(c_stream, Z_NO_FLUSH);
			if (UNIV_UNLIKELY(err != Z_OK)) {
				break;
			}
		}

		ut_ad(!c_stream->avail_in);
		ut_ad(c_stream->next_in == rec - REC_N_NEW_EXTRA_BYTES);

		/* Skip the REC_N_NEW_EXTRA_BYTES. */

		c_stream->next_in = (byte*) rec;
	} while (--n_dense);

	return(err);
}

/**************************************************************************
Compress the records of a leaf node of a clustered index. */
static
int
page_zip_compress_clust(
/*====================*/
					/* out: Z_OK, or a zlib error code */
	z_stream*	c_stream,	/* in/out: compressed page stream */
	const rec_t**	recs,		/* in: dense page directory
					sorted by address */
	ulint		n_dense,	/* in: size of recs[] */
	dict_index_t*	index,		/* in: the index of the page */
	ulint*		n_blobs_out,	/* out: number of
					externally stored columns */
	ulint		trx_id_col,	/* index of the trx_id column */
	byte*		deleted,	/* in: dense directory entry pointing
					to the head of the free list */
	byte*		storage,	/* in: end of dense page directory */
	mem_heap_t*	heap)		/* in: temporary memory heap */
{
	int	err		= Z_OK;
	ulint*	offsets		= NULL;
	/* BTR_EXTERN_FIELD_REF storage */
	byte*	externs		= storage - n_dense
		* (DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN);
	ulint	n_blobs		= 0;
	ulint	n_fields	= dict_index_get_n_fields(index);

	do {
764 765
		ulint		i;
		const rec_t*	rec = *recs++;
766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786

		offsets = rec_get_offsets(rec, index, offsets,
					  ULINT_UNDEFINED, &heap);
		ut_ad(rec_offs_n_fields(offsets) == n_fields);

		/* Compress the extra bytes. */
		c_stream->avail_in = rec - REC_N_NEW_EXTRA_BYTES
			- c_stream->next_in;

		if (c_stream->avail_in) {
			err = deflate(c_stream, Z_NO_FLUSH);
			if (UNIV_UNLIKELY(err != Z_OK)) {

				goto func_exit;
			}
		}
		ut_ad(!c_stream->avail_in);
		ut_ad(c_stream->next_in == rec - REC_N_NEW_EXTRA_BYTES);

		/* Compress the data bytes. */

787
		c_stream->next_in = (byte*) rec;
788 789 790 791 792 793

		/* Check if there are any externally stored columns.
		For each externally stored column, store the
		BTR_EXTERN_FIELD_REF separately. */

		for (i = 0; i < n_fields; i++) {
794 795
			ulint		len;
			const byte*	src;
796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835

			if (UNIV_UNLIKELY(i == trx_id_col)) {
				ut_ad(!rec_offs_nth_extern(offsets, i));
				/* Store trx_id and roll_ptr
				in uncompressed form. */
				src = rec_get_nth_field(rec, offsets, i, &len);
				ut_ad(src + DATA_TRX_ID_LEN
				      == rec_get_nth_field(rec, offsets,
							   i + 1, &len));
				ut_ad(len == DATA_ROLL_PTR_LEN);

				/* Compress any preceding bytes. */
				c_stream->avail_in
					= src - c_stream->next_in;

				if (c_stream->avail_in) {
					err = deflate(c_stream, Z_NO_FLUSH);
					if (UNIV_UNLIKELY(err != Z_OK)) {

						goto func_exit;
					}
				}

				ut_ad(!c_stream->avail_in);
				ut_ad(c_stream->next_in == src);

				memcpy(storage
				       - (DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN)
				       * (rec_get_heap_no_new(rec) - 1),
				       c_stream->next_in,
				       DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN);

				c_stream->next_in
					+= DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN;

				/* Skip also roll_ptr */
				i++;
			} else if (rec_offs_nth_extern(offsets, i)) {
				src = rec_get_nth_field(rec, offsets, i, &len);
				ut_ad(dict_index_is_clust(index));
836
				ut_ad(len >= BTR_EXTERN_FIELD_REF_SIZE);
837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891
				src += len - BTR_EXTERN_FIELD_REF_SIZE;

				c_stream->avail_in = src
					- c_stream->next_in;
				if (UNIV_LIKELY(c_stream->avail_in)) {
					err = deflate(c_stream, Z_NO_FLUSH);
					if (UNIV_UNLIKELY(err != Z_OK)) {

						goto func_exit;
					}
				}

				ut_ad(!c_stream->avail_in);
				ut_ad(c_stream->next_in == src);

				/* Reserve space for the data at
				the end of the space reserved for
				the compressed data and the page
				modification log. */

				if (UNIV_UNLIKELY
				    (c_stream->avail_out
				     <= BTR_EXTERN_FIELD_REF_SIZE)) {
					/* out of space */
					goto func_exit;
				}

				ut_ad(externs == c_stream->next_out
				      + c_stream->avail_out
				      + 1/* end of modif. log */);

				c_stream->next_in
					+= BTR_EXTERN_FIELD_REF_SIZE;

				/* Skip deleted records. */
				if (UNIV_LIKELY_NULL
				    (page_zip_dir_find_low(
					    storage, deleted,
					    page_offset(rec)))) {
					continue;
				}

				n_blobs++;
				c_stream->avail_out
					-= BTR_EXTERN_FIELD_REF_SIZE;
				externs -= BTR_EXTERN_FIELD_REF_SIZE;

				/* Copy the BLOB pointer */
				memcpy(externs, c_stream->next_in
				       - BTR_EXTERN_FIELD_REF_SIZE,
				       BTR_EXTERN_FIELD_REF_SIZE);
			}
		}

		/* Compress the last bytes of the record. */
892
		c_stream->avail_in = rec + rec_offs_data_size(offsets)
893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909
			- c_stream->next_in;

		if (c_stream->avail_in) {
			err = deflate(c_stream, Z_NO_FLUSH);
			if (UNIV_UNLIKELY(err != Z_OK)) {

				goto func_exit;
			}
		}
		ut_ad(!c_stream->avail_in);
	} while (--n_dense);

func_exit:
	*n_blobs_out = n_blobs;
	return(err);
}

marko's avatar
marko committed
910 911 912 913 914 915 916 917
/**************************************************************************
Compress a page. */

ibool
page_zip_compress(
/*==============*/
				/* out: TRUE on success, FALSE on failure;
				page_zip will be left intact on failure. */
918
	page_zip_des_t*	page_zip,/* in: size; out: data, n_blobs,
919
				m_start, m_end, m_nonempty */
920
	const page_t*	page,	/* in: uncompressed page */
921 922
	dict_index_t*	index,	/* in: index of the B-tree node */
	mtr_t*		mtr)	/* in: mini-transaction, or NULL */
marko's avatar
marko committed
923 924 925
{
	z_stream	c_stream;
	int		err;
926 927 928
	ulint		n_fields;/* number of index fields needed */
	byte*		fields;	/* index field information */
	byte*		buf;	/* compressed payload of the page */
929
	byte*		buf_end;/* end of buf */
930
	ulint		n_dense;
931
	ulint		slot_size;/* amount of uncompressed bytes per record */
932
	const rec_t**	recs;	/* dense page directory, sorted by address */
933
	mem_heap_t*	heap;
934 935 936 937
	ulint		trx_id_col;
	ulint*		offsets	= NULL;
	ulint		n_blobs	= 0;
	byte*		storage;/* storage of uncompressed columns */
938

939 940
	ut_a(page_is_comp(page));
	ut_a(fil_page_get_type(page) == FIL_PAGE_INDEX);
941
	ut_ad(page_simple_validate_new((page_t*) page));
942
	ut_ad(page_zip_simple_validate(page_zip));
943 944 945 946 947 948 949

	/* Check the data that will be omitted. */
	ut_a(!memcmp(page + (PAGE_NEW_INFIMUM - REC_N_NEW_EXTRA_BYTES),
		     infimum_extra, sizeof infimum_extra));
	ut_a(!memcmp(page + PAGE_NEW_INFIMUM,
		     infimum_data, sizeof infimum_data));
	ut_a(page[PAGE_NEW_SUPREMUM - REC_N_NEW_EXTRA_BYTES]
950 951
	     /* info_bits == 0, n_owned <= max */
	     <= PAGE_DIR_SLOT_MAX_N_OWNED);
952 953
	ut_a(!memcmp(page + (PAGE_NEW_SUPREMUM - REC_N_NEW_EXTRA_BYTES + 1),
		     supremum_extra_data, sizeof supremum_extra_data));
954

955 956
	if (UNIV_UNLIKELY(!page_get_n_recs(page))) {
		ut_a(rec_get_next_offs(page + PAGE_NEW_INFIMUM, TRUE)
957
		     == PAGE_NEW_SUPREMUM);
958
	}
959

960 961 962 963 964 965
	if (page_is_leaf(page)) {
		n_fields = dict_index_get_n_fields(index);
	} else {
		n_fields = dict_index_get_n_unique_in_tree(index);
	}

966
	/* The dense directory excludes the infimum and supremum records. */
967
	n_dense = page_dir_get_n_heap(page) - PAGE_HEAP_NO_USER_LOW;
968 969 970 971 972 973 974 975
#if defined UNIV_DEBUG || defined UNIV_ZIP_DEBUG
	if (UNIV_UNLIKELY(page_zip_compress_dbg)) {
		fprintf(stderr, "compress %p %p %lu %lu %lu\n",
			(void*) page_zip, (void*) page,
			page_is_leaf(page),
			n_fields, n_dense);
	}
#endif /* UNIV_DEBUG || UNIV_ZIP_DEBUG */
976
	if (UNIV_UNLIKELY(n_dense * PAGE_ZIP_DIR_SLOT_SIZE
977
			  >= page_zip_get_size(page_zip))) {
978 979
		return(FALSE);
	}
980

981
	heap = mem_heap_create(page_zip_get_size(page_zip)
982 983 984
			       + n_fields * (2 + sizeof *offsets)
			       + n_dense * ((sizeof *recs)
					    - PAGE_ZIP_DIR_SLOT_SIZE));
985

986 987
	recs = mem_heap_alloc(heap, n_dense * sizeof *recs);
	memset(recs, 0, n_dense * sizeof *recs);
988

989 990
	fields = mem_heap_alloc(heap, (n_fields + 1) * 2);

991 992
	buf = mem_heap_alloc(heap, page_zip_get_size(page_zip) - PAGE_DATA);
	buf_end = buf + page_zip_get_size(page_zip) - PAGE_DATA;
993

marko's avatar
marko committed
994
	/* Compress the data payload. */
995
	c_stream.zalloc = page_zip_malloc;
996
	c_stream.zfree = page_zip_free;
marko's avatar
marko committed
997 998 999 1000 1001 1002
	c_stream.opaque = (voidpf) 0;

	err = deflateInit(&c_stream, Z_DEFAULT_COMPRESSION);
	ut_a(err == Z_OK);

	c_stream.next_out = buf;
1003
	/* Subtract the space reserved for uncompressed data. */
1004 1005
	/* Page header and the end marker of the modification log */
	c_stream.avail_out = buf_end - buf - 1;
1006 1007
	/* Dense page directory and uncompressed columns, if any */
	if (page_is_leaf(page)) {
1008
		if (dict_index_is_clust(index)) {
1009 1010
			trx_id_col = dict_index_get_sys_col_pos(
				index, DATA_TRX_ID);
1011 1012 1013
			ut_ad(trx_id_col > 0);
			ut_ad(trx_id_col != ULINT_UNDEFINED);

1014
			slot_size = PAGE_ZIP_DIR_SLOT_SIZE
1015
				+ DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN;
1016
		} else {
1017 1018
			/* Signal the absence of trx_id
			in page_zip_fields_encode() */
1019 1020
			ut_ad(dict_index_get_sys_col_pos(index, DATA_TRX_ID)
			      == ULINT_UNDEFINED);
1021
			trx_id_col = 0;
1022
			slot_size = PAGE_ZIP_DIR_SLOT_SIZE;
1023
		}
1024
	} else {
1025
		slot_size = PAGE_ZIP_DIR_SLOT_SIZE + REC_NODE_PTR_SIZE;
1026
		trx_id_col = ULINT_UNDEFINED;
1027 1028
	}

1029 1030 1031 1032 1033
	if (UNIV_UNLIKELY(c_stream.avail_out < n_dense * slot_size)) {
		goto zlib_error;
	}

	c_stream.avail_out -= n_dense * slot_size;
1034 1035
	c_stream.avail_in = page_zip_fields_encode(n_fields, index,
						   trx_id_col, fields);
1036
	c_stream.next_in = fields;
1037
	if (UNIV_LIKELY(!trx_id_col)) {
1038 1039
		trx_id_col = ULINT_UNDEFINED;
	}
1040

1041 1042 1043 1044 1045
	err = deflate(&c_stream, Z_FULL_FLUSH);
	if (err != Z_OK) {
		goto zlib_error;
	}

1046 1047
	ut_ad(!c_stream.avail_in);

1048
	page_zip_dir_encode(page, buf_end, recs);
1049 1050 1051

	c_stream.next_in = (byte*) page + PAGE_ZIP_START;

1052
	storage = buf_end - n_dense * PAGE_ZIP_DIR_SLOT_SIZE;
1053

1054
	/* Compress the records in heap_no order. */
1055
	if (UNIV_UNLIKELY(!n_dense)) {
1056 1057
	} else if (!page_is_leaf(page)) {
		/* This is a node pointer page. */
1058 1059 1060 1061 1062
		err = page_zip_compress_node_ptrs(&c_stream, recs, n_dense,
						  index, storage, heap);
		if (UNIV_UNLIKELY(err != Z_OK)) {
			goto zlib_error;
		}
1063
	} else if (UNIV_LIKELY(trx_id_col == ULINT_UNDEFINED)) {
1064 1065 1066 1067 1068
		/* This is a leaf page in a secondary index. */
		err = page_zip_compress_sec(&c_stream, recs, n_dense);
		if (UNIV_UNLIKELY(err != Z_OK)) {
			goto zlib_error;
		}
1069 1070
	} else {
		/* This is a leaf page in a clustered index. */
1071 1072
		err = page_zip_compress_clust(&c_stream, recs, n_dense,
					      index, &n_blobs, trx_id_col,
1073
					      buf_end - PAGE_ZIP_DIR_SLOT_SIZE
1074
					      * page_get_n_recs(page),
1075 1076 1077 1078
					      storage, heap);
		if (UNIV_UNLIKELY(err != Z_OK)) {
			goto zlib_error;
		}
1079 1080
	}

1081 1082
	/* Finish the compression. */
	ut_ad(!c_stream.avail_in);
1083
	/* Compress any trailing garbage, in case the last record was
1084 1085
	allocated from an originally longer space on the free list,
	or the data of the last record from page_zip_compress_sec(). */
1086
	c_stream.avail_in
1087
		= page_header_get_field(page, PAGE_HEAP_TOP)
1088
		- (c_stream.next_in - page);
1089
	ut_a(c_stream.avail_in <= UNIV_PAGE_SIZE - PAGE_ZIP_START - PAGE_DIR);
marko's avatar
marko committed
1090 1091

	err = deflate(&c_stream, Z_FINISH);
1092

1093
	if (UNIV_UNLIKELY(err != Z_STREAM_END)) {
1094
zlib_error:
marko's avatar
marko committed
1095
		deflateEnd(&c_stream);
1096
		mem_heap_free(heap);
marko's avatar
marko committed
1097 1098 1099 1100 1101 1102
		return(FALSE);
	}

	err = deflateEnd(&c_stream);
	ut_a(err == Z_OK);

1103
	ut_ad(buf + c_stream.total_out == c_stream.next_out);
1104 1105
	ut_ad((ulint) (storage - c_stream.next_out) >= c_stream.avail_out);

1106 1107 1108 1109
	/* Zero out the area reserved for the modification log.
	Space for the end marker of the modification log is not
	included in avail_out. */
	memset(c_stream.next_out, 0, c_stream.avail_out + 1/* end marker */);
1110

1111 1112 1113 1114 1115
#ifdef UNIV_DEBUG
	page_zip->m_start =
#endif /* UNIV_DEBUG */
		page_zip->m_end = PAGE_DATA + c_stream.total_out;
	page_zip->m_nonempty = FALSE;
1116
	page_zip->n_blobs = n_blobs;
1117 1118 1119
	/* Copy those header fields that will not be written
	in buf_flush_init_for_writing() */
	memcpy(page_zip->data + FIL_PAGE_PREV, page + FIL_PAGE_PREV,
1120
	       FIL_PAGE_LSN - FIL_PAGE_PREV);
1121 1122
	memcpy(page_zip->data + FIL_PAGE_TYPE, page + FIL_PAGE_TYPE, 2);
	memcpy(page_zip->data + FIL_PAGE_DATA, page + FIL_PAGE_DATA,
1123
	       PAGE_DATA - FIL_PAGE_DATA);
1124
	/* Copy the rest of the compressed page */
1125 1126
	memcpy(page_zip->data + PAGE_DATA, buf,
	       page_zip_get_size(page_zip) - PAGE_DATA);
1127
	mem_heap_free(heap);
1128
#ifdef UNIV_ZIP_DEBUG
1129
	ut_a(page_zip_validate(page_zip, page));
1130
#endif /* UNIV_ZIP_DEBUG */
marko's avatar
marko committed
1131

1132 1133 1134 1135
	if (mtr) {
		page_zip_compress_write_log(page_zip, page, index, mtr);
	}

1136
	return(TRUE);
marko's avatar
marko committed
1137 1138
}

1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159
/**************************************************************************
Compare two page directory entries. */
UNIV_INLINE
ibool
page_zip_dir_cmp(
/*=============*/
				/* out: positive if rec1 > rec2 */
	const rec_t*	rec1,	/* in: rec1 */
	const rec_t*	rec2)	/* in: rec2 */
{
	return(rec1 > rec2);
}

/**************************************************************************
Sort the dense page directory by address (heap_no). */
static
void
page_zip_dir_sort(
/*==============*/
	rec_t**	arr,	/* in/out: dense page directory */
	rec_t**	aux_arr,/* in/out: work area */
1160 1161
	ulint	low,	/* in: lower bound of the sorting area, inclusive */
	ulint	high)	/* in: upper bound of the sorting area, exclusive */
1162 1163
{
	UT_SORT_FUNCTION_BODY(page_zip_dir_sort, arr, aux_arr, low, high,
1164
			      page_zip_dir_cmp);
1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199
}

/**************************************************************************
Deallocate the index information initialized by page_zip_fields_decode(). */
static
void
page_zip_fields_free(
/*=================*/
	dict_index_t*	index)	/* in: dummy index to be freed */
{
	if (index) {
		dict_table_t*	table = index->table;
		mem_heap_free(index->heap);
		mutex_free(&(table->autoinc_mutex));
		mem_heap_free(table->heap);
	}
}

/**************************************************************************
Read the index information for the compressed page. */
static
dict_index_t*
page_zip_fields_decode(
/*===================*/
				/* out,own: dummy index describing the page,
				or NULL on error */
	const byte*	buf,	/* in: index information */
	const byte*	end,	/* in: end of buf */
	ulint*		trx_id_col)/* in: NULL for non-leaf pages;
				for leaf pages, pointer to where to store
				the position of the trx_id column */
{
	const byte*	b;
	ulint		n;
	ulint		i;
marko's avatar
marko committed
1200
	ulint		val;
1201 1202 1203 1204 1205 1206 1207 1208 1209 1210
	dict_table_t*	table;
	dict_index_t*	index;

	/* Determine the number of fields. */
	for (b = buf, n = 0; b < end; n++) {
		if (*b++ & 0x80) {
			b++; /* skip the second byte */
		}
	}

marko's avatar
marko committed
1211 1212
	n--; /* n_nullable or trx_id */

1213
	if (UNIV_UNLIKELY(n > REC_MAX_N_FIELDS)
1214
	    || UNIV_UNLIKELY(b > end)) {
1215 1216 1217 1218

		return(NULL);
	}

1219
	table = dict_mem_table_create("ZIP_DUMMY", DICT_HDR_SPACE, n,
1220
				      DICT_TF_COMPACT);
1221
	index = dict_mem_index_create("ZIP_DUMMY", "ZIP_DUMMY",
1222
				      DICT_HDR_SPACE, 0, n);
1223 1224 1225 1226 1227 1228 1229 1230 1231 1232
	index->table = table;
	index->n_uniq = n;
	/* avoid ut_ad(index->cached) in dict_index_get_n_unique_in_tree */
	index->cached = TRUE;

	/* Initialize the fields. */
	for (b = buf, i = 0; i < n; i++) {
		ulint	mtype;
		ulint	len;

marko's avatar
marko committed
1233 1234
		val = *b++;

1235
		if (UNIV_UNLIKELY(val & 0x80)) {
1236
			/* fixed length > 62 bytes */
1237
			val = (val & 0x7f) << 8 | *b++;
1238 1239 1240 1241
			len = val >> 1;
			mtype = DATA_FIXBINARY;
		} else if (UNIV_UNLIKELY(val >= 126)) {
			/* variable length with max > 255 bytes */
1242 1243
			len = 0x7fff;
			mtype = DATA_BINARY;
1244 1245 1246 1247 1248 1249 1250
		} else if (val <= 1) {
			/* variable length with max <= 255 bytes */
			len = 0;
			mtype = DATA_BINARY;
		} else {
			/* fixed length < 62 bytes */
			len = val >> 1;
1251 1252
			mtype = DATA_FIXBINARY;
		}
1253

1254
		dict_mem_table_add_col(table, "DUMMY", mtype,
1255
				       val & 1 ? DATA_NOT_NULL : 0, len);
1256
		dict_index_add_col(index, table,
1257
				   dict_table_get_nth_col(table, i), 0);
1258 1259
	}

marko's avatar
marko committed
1260 1261 1262 1263 1264
	val = *b++;
	if (UNIV_UNLIKELY(val & 0x80)) {
		val = (val & 0x7f) << 8 | *b++;
	}

1265 1266 1267 1268 1269 1270 1271 1272 1273
	/* Decode the position of the trx_id column. */
	if (trx_id_col) {
		if (UNIV_UNLIKELY(val >= n)) {
			page_zip_fields_free(index);
			index = NULL;
		}

		if (!val) {
			val = ULINT_UNDEFINED;
1274 1275
		} else {
			index->type = DICT_CLUSTERED;
1276 1277 1278
		}

		*trx_id_col = val;
marko's avatar
marko committed
1279 1280 1281 1282 1283 1284 1285 1286
	} else {
		/* Decode the number of nullable fields. */
		if (UNIV_UNLIKELY(index->n_nullable > val)) {
			page_zip_fields_free(index);
			index = NULL;
		} else {
			index->n_nullable = val;
		}
1287 1288 1289 1290 1291
	}

	ut_ad(b == end);

	return(index);
1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309
}

/**************************************************************************
Populate the sparse page directory from the dense directory. */
static
ibool
page_zip_dir_decode(
/*================*/
					/* out: TRUE on success,
					FALSE on failure */
	const page_zip_des_t*	page_zip,/* in: dense page directory on
					compressed page */
	page_t*			page,	/* in: compact page with valid header;
					out: trailer and sparse page directory
					filled in */
	rec_t**			recs,	/* out: dense page directory sorted by
					ascending address (and heap_no) */
	rec_t**			recs_aux,/* in/out: scratch area */
1310
	ulint			n_dense)/* in: number of user records, and
1311 1312 1313 1314 1315 1316 1317 1318
					size of recs[] and recs_aux[] */
{
	ulint	i;
	ulint	n_recs;
	byte*	slot;

	n_recs = page_get_n_recs(page);

1319 1320 1321 1322
	if (UNIV_UNLIKELY(n_recs > n_dense)) {
		return(FALSE);
	}

1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345
	/* Traverse the list of stored records in the sorting order,
	starting from the first user record. */

	slot = page + (UNIV_PAGE_SIZE - PAGE_DIR - PAGE_DIR_SLOT_SIZE);
	UNIV_PREFETCH_RW(slot);

	/* Zero out the page trailer. */
	memset(slot + PAGE_DIR_SLOT_SIZE, 0, PAGE_DIR);

	mach_write_to_2(slot, PAGE_NEW_INFIMUM);
	slot -= PAGE_DIR_SLOT_SIZE;
	UNIV_PREFETCH_RW(slot);

	/* Initialize the sparse directory and copy the dense directory. */
	for (i = 0; i < n_recs; i++) {
		ulint	offs = page_zip_dir_get(page_zip, i);

		if (offs & PAGE_ZIP_DIR_SLOT_OWNED) {
			mach_write_to_2(slot, offs & PAGE_ZIP_DIR_SLOT_MASK);
			slot -= PAGE_DIR_SLOT_SIZE;
			UNIV_PREFETCH_RW(slot);
		}

1346
		if (UNIV_UNLIKELY((offs & PAGE_ZIP_DIR_SLOT_MASK)
1347
				  < PAGE_ZIP_START + REC_N_NEW_EXTRA_BYTES)) {
1348 1349
			return(FALSE);
		}
1350

1351 1352 1353 1354
		recs[i] = page + (offs & PAGE_ZIP_DIR_SLOT_MASK);
	}

	mach_write_to_2(slot, PAGE_NEW_SUPREMUM);
1355 1356 1357
	if (UNIV_UNLIKELY
	    (slot != page_dir_get_nth_slot(page,
					   page_dir_get_n_slots(page) - 1))) {
1358 1359 1360 1361
		return(FALSE);
	}

	/* Copy the rest of the dense directory. */
1362
	for (; i < n_dense; i++) {
1363 1364 1365 1366 1367 1368 1369 1370 1371
		ulint	offs = page_zip_dir_get(page_zip, i);

		if (UNIV_UNLIKELY(offs & ~PAGE_ZIP_DIR_SLOT_MASK)) {
			return(FALSE);
		}

		recs[i] = page + offs;
	}

1372
	if (UNIV_LIKELY(n_dense > 1)) {
1373
		page_zip_dir_sort(recs, recs_aux, 0, n_dense);
1374 1375 1376 1377
	}
	return(TRUE);
}

1378 1379
/**************************************************************************
Initialize the REC_N_NEW_EXTRA_BYTES of each record. */
1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411
static
ibool
page_zip_set_extra_bytes(
/*=====================*/
					/* out: TRUE on success,
					FALSE on failure */
	const page_zip_des_t*	page_zip,/* in: compressed page */
	page_t*			page,	/* in/out: uncompressed page */
	ulint			info_bits)/* in: REC_INFO_MIN_REC_FLAG or 0 */
{
	ulint	n;
	ulint	i;
	ulint	n_owned = 1;
	ulint	offs;
	rec_t*	rec;

	n = page_get_n_recs(page);
	rec = page + PAGE_NEW_INFIMUM;

	for (i = 0; i < n; i++) {
		offs = page_zip_dir_get(page_zip, i);

		if (UNIV_UNLIKELY(offs & PAGE_ZIP_DIR_SLOT_DEL)) {
			info_bits |= REC_INFO_DELETED_FLAG;
		}
		if (UNIV_UNLIKELY(offs & PAGE_ZIP_DIR_SLOT_OWNED)) {
			info_bits |= n_owned;
			n_owned = 1;
		} else {
			n_owned++;
		}
		offs &= PAGE_ZIP_DIR_SLOT_MASK;
1412
		if (UNIV_UNLIKELY(offs < PAGE_ZIP_START
1413
				  + REC_N_NEW_EXTRA_BYTES)) {
1414 1415
			return(FALSE);
		}
1416

1417
		rec_set_next_offs_new(rec, offs);
1418
		rec = page + offs;
1419 1420
		rec[-REC_N_NEW_EXTRA_BYTES] = info_bits;
		info_bits = 0;
1421 1422 1423
	}

	/* Set the next pointer of the last user record. */
1424
	rec_set_next_offs_new(rec, PAGE_NEW_SUPREMUM);
1425 1426 1427 1428

	/* Set n_owned of the supremum record. */
	page[PAGE_NEW_SUPREMUM - REC_N_NEW_EXTRA_BYTES] = n_owned;

1429
	/* The dense directory excludes the infimum and supremum records. */
1430
	n = page_dir_get_n_heap(page) - PAGE_HEAP_NO_USER_LOW;
1431 1432

	if (i >= n) {
1433

1434
		return(UNIV_LIKELY(i == n));
1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448
	}

	offs = page_zip_dir_get(page_zip, i);

	/* Set the extra bytes of deleted records on the free list. */
	for (;;) {
		if (UNIV_UNLIKELY(!offs)
		    || UNIV_UNLIKELY(offs & ~PAGE_ZIP_DIR_SLOT_MASK)) {
			return(FALSE);
		}

		rec = page + offs;
		rec[-REC_N_NEW_EXTRA_BYTES] = 0; /* info_bits and n_owned */

1449 1450 1451 1452 1453
		if (++i == n) {
			break;
		}

		offs = page_zip_dir_get(page_zip, i);
1454
		rec_set_next_offs_new(rec, offs);
1455 1456 1457 1458
	}

	/* Terminate the free list. */
	rec[-REC_N_NEW_EXTRA_BYTES] = 0; /* info_bits and n_owned */
1459
	rec_set_next_offs_new(rec, 0);
1460

1461
	return(TRUE);
1462 1463
}

1464
/**************************************************************************
1465 1466
Apply the modification log to an uncompressed page.
Do not copy the fields that are stored separately. */
1467 1468 1469 1470 1471 1472 1473
static
const byte*
page_zip_apply_log(
/*===============*/
				/* out: pointer to end of modification log,
				or NULL on failure */
	const byte*	data,	/* in: modification log */
1474
	ulint		size,	/* in: maximum length of the log, in bytes */
1475
	rec_t**		recs,	/* in: dense page directory,
1476 1477
				sorted by address (indexed by
				heap_no - PAGE_HEAP_NO_USER_LOW) */
1478
	ulint		n_dense,/* in: size of recs[] */
1479 1480
	ulint		trx_id_col,/* in: column number of trx_id in the index,
				or ULINT_UNDEFINED if none */
1481 1482 1483 1484 1485 1486
	ulint		heap_status,
				/* in: heap_no and status bits for
				the next record to uncompress */
	dict_index_t*	index,	/* in: index of the page */
	ulint*		offsets)/* in/out: work area for
				rec_get_offsets_reverse() */
1487
{
1488 1489
	const byte* const end = data + size;

1490
	for (;;) {
1491
		ulint	val;
1492 1493 1494 1495
		rec_t*	rec;
		ulint	len;
		ulint	hs;

1496 1497
		val = *data++;
		if (UNIV_UNLIKELY(!val)) {
1498
			return(data - 1);
1499
		}
1500
		if (val & 0x80) {
1501
			val = (val & 0x7f) << 8 | *data++;
1502 1503 1504
			if (UNIV_UNLIKELY(!val)) {
				return(NULL);
			}
1505 1506
		}
		if (UNIV_UNLIKELY(data >= end)) {
1507 1508
			return(NULL);
		}
1509
		if (UNIV_UNLIKELY((val >> 1) > n_dense)) {
1510 1511
			return(NULL);
		}
1512 1513

		/* Determine the heap number and status bits of the record. */
1514 1515 1516 1517 1518 1519 1520
		rec = recs[(val >> 1) - 1];

		if (val & 1) {
			/* Clear the data bytes of the record. */
			mem_heap_t*	heap	= NULL;
			ulint*		offs;
			offs = rec_get_offsets(rec, index, offsets,
1521
					       ULINT_UNDEFINED, &heap);
1522 1523 1524 1525 1526 1527 1528 1529 1530
			memset(rec, 0, rec_offs_data_size(offs));

			if (UNIV_LIKELY_NULL(heap)) {
				mem_heap_free(heap);
			}
			continue;
		}

		hs = ((val >> 1) + 1) << REC_HEAP_NO_SHIFT;
1531 1532 1533 1534 1535 1536 1537 1538 1539 1540
		hs |= heap_status & ((1 << REC_HEAP_NO_SHIFT) - 1);

		/* This may either be an old record that is being
		overwritten (updated in place, or allocated from
		the free list), or a new record, with the next
		available_heap_no. */
		if (UNIV_UNLIKELY(hs > heap_status)) {
			return(NULL);
		} else if (hs == heap_status) {
			/* A new record was allocated from the heap. */
marko's avatar
marko committed
1541
			heap_status += 1 << REC_HEAP_NO_SHIFT;
1542 1543
		}

marko's avatar
marko committed
1544 1545 1546 1547
		mach_write_to_2(rec - REC_NEW_HEAP_NO, hs);
#if REC_STATUS_NODE_PTR != TRUE
# error "REC_STATUS_NODE_PTR != TRUE"
#endif
1548
		rec_get_offsets_reverse(data, index,
1549 1550
					hs & REC_STATUS_NODE_PTR,
					offsets);
marko's avatar
marko committed
1551
		rec_offs_make_valid(rec, index, offsets);
1552 1553 1554

		/* Copy the extra bytes (backwards). */
		{
1555 1556 1557 1558
			byte*	start	= rec_get_start(rec, offsets);
			byte*	b	= rec - REC_N_NEW_EXTRA_BYTES;
			while (b != start) {
				*--b = *data++;
1559 1560 1561 1562
			}
		}

		/* Copy the data bytes. */
marko's avatar
marko committed
1563
		if (UNIV_UNLIKELY(hs & REC_STATUS_NODE_PTR)) {
1564 1565 1566 1567 1568
			/* Non-leaf nodes should not contain any
			externally stored columns. */
			if (UNIV_UNLIKELY(rec_offs_any_extern(offsets))) {
				return(NULL);
			}
1569

1570
			len = rec_offs_data_size(offsets)
1571
				- REC_NODE_PTR_SIZE;
1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583
			/* Copy the data bytes, except node_ptr. */
			if (UNIV_UNLIKELY(data + len >= end)) {
				return(NULL);
			}
			memcpy(rec, data, len);
			data += len;
		} else {
			ulint	i;
			byte*	next_out = rec;

			/* Check if there are any externally stored columns.
			For each externally stored column, skip the
1584
			BTR_EXTERN_FIELD_REF. */
1585 1586

			for (i = 0; i < rec_offs_n_fields(offsets); i++) {
1587 1588 1589 1590
				byte*	dst;

				if (UNIV_UNLIKELY(i == trx_id_col)) {
					/* Skip trx_id and roll_ptr */
1591 1592
					dst = rec_get_nth_field(rec, offsets,
								i, &len);
1593
					if (UNIV_UNLIKELY(dst - next_out
1594 1595 1596 1597
							  >= end - data)
					    || UNIV_UNLIKELY
					    (len < (DATA_TRX_ID_LEN
						    + DATA_ROLL_PTR_LEN))
1598 1599
					    || rec_offs_nth_extern(offsets,
								   i)) {
1600 1601 1602 1603 1604 1605
						return(NULL);
					}

					memcpy(next_out, data, dst - next_out);
					data += dst - next_out;
					next_out = dst + (DATA_TRX_ID_LEN
1606
							  + DATA_ROLL_PTR_LEN);
1607
				} else if (rec_offs_nth_extern(offsets, i)) {
1608 1609
					dst = rec_get_nth_field(rec, offsets,
								i, &len);
1610 1611
					ut_ad(len
					      >= BTR_EXTERN_FIELD_REF_SIZE);
1612 1613 1614 1615 1616 1617 1618

					len += dst - next_out
						- BTR_EXTERN_FIELD_REF_SIZE;

					if (UNIV_UNLIKELY(data + len >= end)) {
						return(NULL);
					}
1619

1620 1621 1622 1623 1624 1625 1626
					memcpy(next_out, data, len);
					data += len;
					next_out += len
						+ BTR_EXTERN_FIELD_REF_SIZE;
				}
			}

1627 1628
			/* Copy the last bytes of the record. */
			len = rec_get_end(rec, offsets) - next_out;
1629 1630 1631 1632 1633 1634
			if (UNIV_UNLIKELY(data + len >= end)) {
				return(NULL);
			}
			memcpy(next_out, data, len);
			data += len;
		}
1635 1636 1637
	}
}

marko's avatar
marko committed
1638
/**************************************************************************
1639 1640
Decompress the records of a node pointer page. */
static
marko's avatar
marko committed
1641
ibool
1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653
page_zip_decompress_node_ptrs(
/*==========================*/
					/* out: TRUE on success,
					FALSE on failure */
	page_zip_des_t*	page_zip,	/* in/out: compressed page */
	z_stream*	d_stream,	/* in/out: compressed page stream */
	rec_t**		recs,		/* in: dense page directory
					sorted by address */
	ulint		n_dense,	/* in: size of recs[] */
	dict_index_t*	index,		/* in: the index of the page */
	ulint*		offsets,	/* in/out: temporary offsets */
	mem_heap_t*	heap)		/* in: temporary memory heap */
marko's avatar
marko committed
1654
{
1655
	ulint		heap_status = REC_STATUS_NODE_PTR
1656
		| PAGE_HEAP_NO_USER_LOW << REC_HEAP_NO_SHIFT;
1657
	ulint		slot;
1658
	const byte*	storage;
marko's avatar
marko committed
1659

1660 1661 1662
	/* Subtract the space reserved for uncompressed data. */
	d_stream->avail_in -= n_dense
		* (PAGE_ZIP_DIR_SLOT_SIZE + REC_NODE_PTR_SIZE);
marko's avatar
marko committed
1663

1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726
	/* Decompress the records in heap_no order. */
	for (slot = 0; slot < n_dense; slot++) {
		rec_t*	rec = recs[slot];

		d_stream->avail_out = rec - REC_N_NEW_EXTRA_BYTES
			- d_stream->next_out;

		ut_ad(d_stream->avail_out < UNIV_PAGE_SIZE
		      - PAGE_ZIP_START - PAGE_DIR);
		switch (inflate(d_stream, Z_SYNC_FLUSH)) {
		case Z_STREAM_END:
			/* Apparently, n_dense has grown
			since the time the page was last compressed. */
			goto zlib_done;
		case Z_OK:
		case Z_BUF_ERROR:
			if (!d_stream->avail_out) {
				break;
			}
			/* fall through */
		default:
			goto zlib_error;
		}

		ut_ad(d_stream->next_out == rec - REC_N_NEW_EXTRA_BYTES);
		/* Prepare to decompress the data bytes. */
		d_stream->next_out = rec;
		/* Set heap_no and the status bits. */
		mach_write_to_2(rec - REC_NEW_HEAP_NO, heap_status);
		heap_status += 1 << REC_HEAP_NO_SHIFT;

		/* Read the offsets. The status bits are needed here. */
		offsets = rec_get_offsets(rec, index, offsets,
					  ULINT_UNDEFINED, &heap);

		/* Non-leaf nodes should not have any externally
		stored columns. */
		ut_ad(!rec_offs_any_extern(offsets));

		/* Decompress the data bytes, except node_ptr. */
		d_stream->avail_out = rec_offs_data_size(offsets)
			- REC_NODE_PTR_SIZE;

		switch (inflate(d_stream, Z_SYNC_FLUSH)) {
		case Z_STREAM_END:
			goto zlib_done;
		case Z_OK:
		case Z_BUF_ERROR:
			if (!d_stream->avail_out) {
				break;
			}
			/* fall through */
		default:
			goto zlib_error;
		}

		/* Clear the node pointer in case the record
		will be deleted and the space will be reallocated
		to a smaller record. */
		memset(d_stream->next_out, 0, REC_NODE_PTR_SIZE);
		d_stream->next_out += REC_NODE_PTR_SIZE;

		ut_ad(d_stream->next_out == rec_get_end(rec, offsets));
1727
	}
1728

1729 1730 1731 1732 1733 1734 1735
	/* Decompress any trailing garbage, in case the last record was
	allocated from an originally longer space on the free list. */
	d_stream->avail_out = page_header_get_field(page_zip->data,
						    PAGE_HEAP_TOP)
		- page_offset(d_stream->next_out);
	if (UNIV_UNLIKELY(d_stream->avail_out > UNIV_PAGE_SIZE
			  - PAGE_ZIP_START - PAGE_DIR)) {
1736

1737 1738
		goto zlib_error;
	}
1739

1740 1741 1742
	if (UNIV_UNLIKELY(inflate(d_stream, Z_FINISH) != Z_STREAM_END)) {
zlib_error:
		inflateEnd(d_stream);
1743 1744 1745
		return(FALSE);
	}

1746 1747 1748 1749 1750 1751
	/* Note that d_stream->avail_out > 0 may hold here
	if the modification log is nonempty. */

zlib_done:
	if (UNIV_UNLIKELY(inflateEnd(d_stream) != Z_OK)) {
		ut_error;
1752 1753
	}

1754 1755
	{
		page_t*	page = page_align(d_stream->next_out);
marko's avatar
marko committed
1756

1757 1758 1759 1760 1761
		/* Clear the unused heap space on the uncompressed page. */
		memset(d_stream->next_out, 0,
		       page_dir_get_nth_slot(page,
					     page_dir_get_n_slots(page) - 1)
		       - d_stream->next_out);
marko's avatar
marko committed
1762
	}
marko's avatar
marko committed
1763

1764
#ifdef UNIV_DEBUG
1765
	page_zip->m_start = PAGE_DATA + d_stream->total_in;
1766
#endif /* UNIV_DEBUG */
1767

1768 1769 1770
	/* Apply the modification log. */
	{
		const byte*	mod_log_ptr;
1771
		mod_log_ptr = page_zip_apply_log(d_stream->next_in,
1772 1773 1774 1775
						 d_stream->avail_in + 1,
						 recs, n_dense,
						 ULINT_UNDEFINED, heap_status,
						 index, offsets);
1776

1777 1778 1779 1780
		if (UNIV_UNLIKELY(!mod_log_ptr)) {
			return(FALSE);
		}
		page_zip->m_end = mod_log_ptr - page_zip->data;
1781
		page_zip->m_nonempty = mod_log_ptr != d_stream->next_in;
1782
		ut_a(page_zip_get_trailer_len(page_zip, index, NULL)
1783
		     + page_zip->m_end < page_zip_get_size(page_zip));
1784
	}
1785

1786
	/* Restore the uncompressed columns in heap_no order. */
1787
	storage	= page_zip->data + page_zip_get_size(page_zip)
1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801
		- n_dense * PAGE_ZIP_DIR_SLOT_SIZE;

	for (slot = 0; slot < n_dense; slot++) {
		rec_t*		rec	= recs[slot];

		offsets = rec_get_offsets(rec, index, offsets,
					  ULINT_UNDEFINED, &heap);
		/* Non-leaf nodes should not have any externally
		stored columns. */
		ut_ad(!rec_offs_any_extern(offsets));
		storage -= REC_NODE_PTR_SIZE;

		memcpy(rec_get_end(rec, offsets) - REC_NODE_PTR_SIZE,
		       storage, REC_NODE_PTR_SIZE);
1802 1803
	}

1804 1805
	return(TRUE);
}
1806

1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822
/**************************************************************************
Decompress the records of a leaf node of a secondary index. */
static
ibool
page_zip_decompress_sec(
/*====================*/
					/* out: TRUE on success,
					FALSE on failure */
	page_zip_des_t*	page_zip,	/* in/out: compressed page */
	z_stream*	d_stream,	/* in/out: compressed page stream */
	rec_t**		recs,		/* in: dense page directory
					sorted by address */
	ulint		n_dense,	/* in: size of recs[] */
	dict_index_t*	index,		/* in: the index of the page */
	ulint*		offsets)	/* in/out: temporary offsets */
{
1823 1824
	ulint	heap_status	= REC_STATUS_ORDINARY
		| PAGE_HEAP_NO_USER_LOW << REC_HEAP_NO_SHIFT;
1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872
	ulint	slot;

	/* Subtract the space reserved for uncompressed data. */
	d_stream->avail_in -= n_dense * PAGE_ZIP_DIR_SLOT_SIZE;

	for (slot = 0; slot < n_dense; slot++) {
		rec_t*	rec = recs[slot];

		/* Decompress everything up to this record. */
		d_stream->avail_out = rec - REC_N_NEW_EXTRA_BYTES
			- d_stream->next_out;

		if (UNIV_LIKELY(d_stream->avail_out)) {
			switch (inflate(d_stream, Z_SYNC_FLUSH)) {
			case Z_STREAM_END:
				/* Apparently, n_dense has grown
				since the time the page was last compressed. */
				goto zlib_done;
			case Z_OK:
			case Z_BUF_ERROR:
				if (!d_stream->avail_out) {
					break;
				}
				/* fall through */
			default:
				goto zlib_error;
			}
		}

		ut_ad(d_stream->next_out == rec - REC_N_NEW_EXTRA_BYTES);

		/* Skip the REC_N_NEW_EXTRA_BYTES. */

		d_stream->next_out = rec;

		/* Set heap_no and the status bits. */
		mach_write_to_2(rec - REC_NEW_HEAP_NO, heap_status);
		heap_status += 1 << REC_HEAP_NO_SHIFT;
	}

	/* Decompress the data of the last record and any trailing garbage,
	in case the last record was allocated from an originally longer space
	on the free list. */
	d_stream->avail_out = page_header_get_field(page_zip->data,
						    PAGE_HEAP_TOP)
		- page_offset(d_stream->next_out);
	if (UNIV_UNLIKELY(d_stream->avail_out > UNIV_PAGE_SIZE
			  - PAGE_ZIP_START - PAGE_DIR)) {
1873 1874 1875 1876

		goto zlib_error;
	}

1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889
	if (UNIV_UNLIKELY(inflate(d_stream, Z_FINISH) != Z_STREAM_END)) {
zlib_error:
		inflateEnd(d_stream);
		return(FALSE);
	}

	/* Note that d_stream->avail_out > 0 may hold here
	if the modification log is nonempty. */

zlib_done:
	if (UNIV_UNLIKELY(inflateEnd(d_stream) != Z_OK)) {
		ut_error;
	}
1890 1891

	{
1892
		page_t*	page = page_align(d_stream->next_out);
1893

1894 1895 1896 1897 1898 1899
		/* Clear the unused heap space on the uncompressed page. */
		memset(d_stream->next_out, 0,
		       page_dir_get_nth_slot(page,
					     page_dir_get_n_slots(page) - 1)
		       - d_stream->next_out);
	}
1900

1901
#ifdef UNIV_DEBUG
1902
	page_zip->m_start = PAGE_DATA + d_stream->total_in;
1903
#endif /* UNIV_DEBUG */
1904 1905 1906 1907

	/* Apply the modification log. */
	{
		const byte*	mod_log_ptr;
1908
		mod_log_ptr = page_zip_apply_log(d_stream->next_in,
1909 1910 1911 1912 1913 1914 1915 1916 1917
						 d_stream->avail_in + 1,
						 recs, n_dense,
						 ULINT_UNDEFINED, heap_status,
						 index, offsets);

		if (UNIV_UNLIKELY(!mod_log_ptr)) {
			return(FALSE);
		}
		page_zip->m_end = mod_log_ptr - page_zip->data;
1918
		page_zip->m_nonempty = mod_log_ptr != d_stream->next_in;
1919
		ut_a(page_zip_get_trailer_len(page_zip, index, NULL)
1920
		     + page_zip->m_end < page_zip_get_size(page_zip));
1921 1922
	}

1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949
	/* There are no uncompressed columns on leaf pages of
	secondary indexes. */

	return(TRUE);
}

/**************************************************************************
Compress the records of a leaf node of a clustered index. */
static
ibool
page_zip_decompress_clust(
/*======================*/
					/* out: TRUE on success,
					FALSE on failure */
	page_zip_des_t*	page_zip,	/* in/out: compressed page */
	z_stream*	d_stream,	/* in/out: compressed page stream */
	rec_t**		recs,		/* in: dense page directory
					sorted by address */
	ulint		n_dense,	/* in: size of recs[] */
	dict_index_t*	index,		/* in: the index of the page */
	ulint		trx_id_col,	/* index of the trx_id column */
	ulint*		offsets,	/* in/out: temporary offsets */
	mem_heap_t*	heap)		/* in: temporary memory heap */
{
	int		err;
	ulint		slot;
	ulint		heap_status	= REC_STATUS_ORDINARY
1950
		| PAGE_HEAP_NO_USER_LOW << REC_HEAP_NO_SHIFT;
1951 1952 1953 1954 1955 1956 1957 1958
	const byte*	storage;
	const byte*	externs;

	/* Subtract the space reserved for uncompressed data. */
	d_stream->avail_in -= n_dense * (PAGE_ZIP_DIR_SLOT_SIZE
					 + DATA_TRX_ID_LEN
					 + DATA_ROLL_PTR_LEN);

1959
	/* Decompress the records in heap_no order. */
1960
	for (slot = 0; slot < n_dense; slot++) {
1961
		rec_t*	rec	= recs[slot];
1962

1963 1964
		d_stream->avail_out = rec - REC_N_NEW_EXTRA_BYTES
			- d_stream->next_out;
1965

1966
		ut_ad(d_stream->avail_out < UNIV_PAGE_SIZE
1967
		      - PAGE_ZIP_START - PAGE_DIR);
1968 1969
		err = inflate(d_stream, Z_SYNC_FLUSH);
		switch (err) {
1970 1971
		case Z_STREAM_END:
			/* Apparently, n_dense has grown
1972
			since the time the page was last compressed. */
1973
			goto zlib_done;
1974
		case Z_OK:
1975
		case Z_BUF_ERROR:
1976
			if (UNIV_LIKELY(!d_stream->avail_out)) {
1977 1978
				break;
			}
1979
			/* fall through */
1980 1981 1982 1983
		default:
			goto zlib_error;
		}

1984
		ut_ad(d_stream->next_out == rec - REC_N_NEW_EXTRA_BYTES);
1985
		/* Prepare to decompress the data bytes. */
1986
		d_stream->next_out = rec;
1987 1988 1989
		/* Set heap_no and the status bits. */
		mach_write_to_2(rec - REC_NEW_HEAP_NO, heap_status);
		heap_status += 1 << REC_HEAP_NO_SHIFT;
1990

1991 1992
		/* Read the offsets. The status bits are needed here. */
		offsets = rec_get_offsets(rec, index, offsets,
1993
					  ULINT_UNDEFINED, &heap);
1994

1995 1996
		/* This is a leaf page in a clustered index. */
		ulint	i;
1997

1998 1999 2000
		/* Check if there are any externally stored columns.
		For each externally stored column, restore the
		BTR_EXTERN_FIELD_REF separately. */
2001

2002 2003 2004
		for (i = 0; i < rec_offs_n_fields(offsets); i++) {
			ulint	len;
			byte*	dst;
2005

2006 2007 2008 2009 2010 2011
			if (UNIV_UNLIKELY(i == trx_id_col)) {
				/* Skip trx_id and roll_ptr */
				dst = rec_get_nth_field(rec, offsets, i, &len);
				if (UNIV_UNLIKELY(len < DATA_TRX_ID_LEN
						  + DATA_ROLL_PTR_LEN)
				    || rec_offs_nth_extern(offsets, i)) {
2012

2013 2014
					goto zlib_error;
				}
2015

2016
				d_stream->avail_out = dst - d_stream->next_out;
2017

2018 2019 2020 2021 2022 2023
				switch (inflate(d_stream, Z_SYNC_FLUSH)) {
				case Z_STREAM_END:
				case Z_OK:
				case Z_BUF_ERROR:
					if (!d_stream->avail_out) {
						break;
2024
					}
2025 2026 2027 2028
					/* fall through */
				default:
					goto zlib_error;
				}
2029

2030
				ut_ad(d_stream->next_out == dst);
2031

2032 2033 2034 2035
				d_stream->next_out += DATA_TRX_ID_LEN
					+ DATA_ROLL_PTR_LEN;
			} else if (rec_offs_nth_extern(offsets, i)) {
				dst = rec_get_nth_field(rec, offsets, i, &len);
2036
				ut_ad(len >= BTR_EXTERN_FIELD_REF_SIZE);
2037
				dst += len - BTR_EXTERN_FIELD_REF_SIZE;
2038

2039 2040 2041 2042 2043 2044 2045 2046
				d_stream->avail_out = dst - d_stream->next_out;
				switch (inflate(d_stream,
						Z_SYNC_FLUSH)) {
				case Z_STREAM_END:
				case Z_OK:
				case Z_BUF_ERROR:
					if (!d_stream->avail_out) {
						break;
2047
					}
2048 2049 2050 2051
					/* fall through */
				default:
					goto zlib_error;
				}
2052

2053
				ut_ad(d_stream->next_out == dst);
2054

2055 2056 2057 2058
				/* Reserve space for the data at
				the end of the space reserved for
				the compressed data and the
				page modification log. */
2059

2060 2061 2062 2063 2064
				if (UNIV_UNLIKELY
				    (d_stream->avail_in
				     <= BTR_EXTERN_FIELD_REF_SIZE)) {
					/* out of space */
					goto zlib_error;
2065
				}
2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081

				/* Clear the BLOB pointer in case
				the record will be deleted and the
				space will not be reused.  Note that
				the final initialization of the BLOB
				pointers (copying from "externs"
				or clearing) will have to take place
				only after the page modification log
				has been applied.  Otherwise, we
				could end up with an uninitialized
				BLOB pointer when a record is deleted,
				reallocated and deleted. */
				memset(d_stream->next_out, 0,
				       BTR_EXTERN_FIELD_REF_SIZE);
				d_stream->next_out
					+= BTR_EXTERN_FIELD_REF_SIZE;
2082
			}
2083
		}
marko's avatar
marko committed
2084

2085 2086 2087
		/* Decompress the last bytes of the record. */
		d_stream->avail_out = rec_get_end(rec, offsets)
			- d_stream->next_out;
2088

2089 2090 2091 2092 2093 2094
		switch (inflate(d_stream, Z_SYNC_FLUSH)) {
		case Z_STREAM_END:
		case Z_OK:
		case Z_BUF_ERROR:
			if (!d_stream->avail_out) {
				break;
2095
			}
2096 2097 2098
			/* fall through */
		default:
			goto zlib_error;
2099
		}
2100 2101
	}

2102 2103
	/* Decompress any trailing garbage, in case the last record was
	allocated from an originally longer space on the free list. */
2104 2105 2106 2107
	d_stream->avail_out = page_header_get_field(page_zip->data,
						    PAGE_HEAP_TOP)
		- page_offset(d_stream->next_out);
	if (UNIV_UNLIKELY(d_stream->avail_out > UNIV_PAGE_SIZE
2108
			  - PAGE_ZIP_START - PAGE_DIR)) {
2109 2110 2111 2112

		goto zlib_error;
	}

2113
	if (UNIV_UNLIKELY(inflate(d_stream, Z_FINISH) != Z_STREAM_END)) {
2114
zlib_error:
2115 2116
		inflateEnd(d_stream);
		return(FALSE);
2117 2118
	}

2119
	/* Note that d_stream->avail_out > 0 may hold here
2120
	if the modification log is nonempty. */
2121 2122

zlib_done:
2123
	if (UNIV_UNLIKELY(inflateEnd(d_stream) != Z_OK)) {
marko's avatar
marko committed
2124 2125
		ut_error;
	}
2126

2127 2128
	{
		page_t*	page = page_align(d_stream->next_out);
2129

2130 2131 2132 2133 2134 2135
		/* Clear the unused heap space on the uncompressed page. */
		memset(d_stream->next_out, 0,
		       page_dir_get_nth_slot(page,
					     page_dir_get_n_slots(page) - 1)
		       - d_stream->next_out);
	}
2136

2137
#ifdef UNIV_DEBUG
2138
	page_zip->m_start = PAGE_DATA + d_stream->total_in;
2139
#endif /* UNIV_DEBUG */
marko's avatar
marko committed
2140 2141

	/* Apply the modification log. */
2142 2143
	{
		const byte*	mod_log_ptr;
2144
		mod_log_ptr = page_zip_apply_log(d_stream->next_in,
2145
						 d_stream->avail_in + 1,
2146 2147 2148
						 recs, n_dense,
						 trx_id_col, heap_status,
						 index, offsets);
2149

2150
		if (UNIV_UNLIKELY(!mod_log_ptr)) {
2151
			return(FALSE);
marko's avatar
marko committed
2152
		}
2153
		page_zip->m_end = mod_log_ptr - page_zip->data;
2154
		page_zip->m_nonempty = mod_log_ptr != d_stream->next_in;
2155
		ut_a(page_zip_get_trailer_len(page_zip, index, NULL)
2156
		     + page_zip->m_end < page_zip_get_size(page_zip));
marko's avatar
marko committed
2157 2158
	}

2159
	storage = page_zip->data + page_zip_get_size(page_zip)
2160 2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200 2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227
		- n_dense * PAGE_ZIP_DIR_SLOT_SIZE;

	externs = storage - n_dense
		* (DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN);

	/* Restore the uncompressed columns in heap_no order. */

	for (slot = 0; slot < n_dense; slot++) {
		ulint	i;
		ulint	len;
		byte*	dst;
		rec_t*	rec	= recs[slot];
		ibool	exists	= !page_zip_dir_find_free(
			page_zip, page_offset(rec));
		offsets = rec_get_offsets(rec, index, offsets,
					  ULINT_UNDEFINED, &heap);

		dst = rec_get_nth_field(rec, offsets,
					trx_id_col, &len);
		ut_ad(len >= DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN);
		storage -= DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN;
		memcpy(dst, storage,
		       DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN);

		/* Check if there are any externally stored
		columns in this record.  For each externally
		stored column, restore or clear the
		BTR_EXTERN_FIELD_REF. */

		for (i = 0; i < rec_offs_n_fields(offsets); i++) {
			if (!rec_offs_nth_extern(offsets, i)) {
				continue;
			}
			dst = rec_get_nth_field(rec, offsets, i, &len);
			ut_ad(len >= BTR_EXTERN_FIELD_REF_SIZE);
			dst += len - BTR_EXTERN_FIELD_REF_SIZE;

			if (UNIV_LIKELY(exists)) {
				/* Existing record:
				restore the BLOB pointer */
				externs -= BTR_EXTERN_FIELD_REF_SIZE;

				memcpy(dst, externs,
				       BTR_EXTERN_FIELD_REF_SIZE);

				page_zip->n_blobs++;
			} else {
				/* Deleted record:
				clear the BLOB pointer */
				memset(dst, 0,
				       BTR_EXTERN_FIELD_REF_SIZE);
			}
		}
	}

	return(TRUE);
}

/**************************************************************************
Decompress a page.  This function should tolerate errors on the compressed
page.  Instead of letting assertions fail, it will return FALSE if an
inconsistency is detected. */

ibool
page_zip_decompress(
/*================*/
				/* out: TRUE on success, FALSE on failure */
	page_zip_des_t*	page_zip,/* in: data, size;
2228
				out: m_start, m_end, m_nonempty, n_blobs */
2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 2240 2241
	page_t*		page)	/* out: uncompressed page, may be trashed */
{
	z_stream	d_stream;
	dict_index_t*	index	= NULL;
	rec_t**		recs;	/* dense page directory, sorted by address */
	ulint		n_dense;/* number of user records on the page */
	ulint		trx_id_col = ULINT_UNDEFINED;
	mem_heap_t*	heap;
	ulint*		offsets;

	ut_ad(page_zip_simple_validate(page_zip));

	/* The dense directory excludes the infimum and supremum records. */
2242
	n_dense = page_dir_get_n_heap(page_zip->data) - PAGE_HEAP_NO_USER_LOW;
2243
	if (UNIV_UNLIKELY(n_dense * PAGE_ZIP_DIR_SLOT_SIZE
2244
			  >= page_zip_get_size(page_zip))) {
2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261
		return(FALSE);
	}

	heap = mem_heap_create(n_dense * (3 * sizeof *recs));
	recs = mem_heap_alloc(heap, n_dense * (2 * sizeof *recs));

#ifdef UNIV_ZIP_DEBUG
	/* Clear the page. */
	memset(page, 0x55, UNIV_PAGE_SIZE);
#endif /* UNIV_ZIP_DEBUG */
	/* Copy the page header. */
	memcpy(page, page_zip->data, PAGE_DATA);

	/* Copy the page directory. */
	if (UNIV_UNLIKELY(!page_zip_dir_decode(page_zip, page, recs,
					       recs + n_dense, n_dense))) {
zlib_error:
2262 2263 2264 2265
		mem_heap_free(heap);
		return(FALSE);
	}

2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279
	/* Copy the infimum and supremum records. */
	memcpy(page + (PAGE_NEW_INFIMUM - REC_N_NEW_EXTRA_BYTES),
	       infimum_extra, sizeof infimum_extra);
	if (UNIV_UNLIKELY(!page_get_n_recs(page))) {
		rec_set_next_offs_new(page + PAGE_NEW_INFIMUM,
				      PAGE_NEW_SUPREMUM);
	} else {
		rec_set_next_offs_new(page + PAGE_NEW_INFIMUM,
				      page_zip_dir_get(page_zip, 0)
				      & PAGE_ZIP_DIR_SLOT_MASK);
	}
	memcpy(page + PAGE_NEW_INFIMUM, infimum_data, sizeof infimum_data);
	memcpy(page + (PAGE_NEW_SUPREMUM - REC_N_NEW_EXTRA_BYTES + 1),
	       supremum_extra_data, sizeof supremum_extra_data);
2280

2281 2282 2283
	d_stream.zalloc = page_zip_malloc;
	d_stream.zfree = page_zip_free;
	d_stream.opaque = (voidpf) 0;
2284

2285 2286
	if (UNIV_UNLIKELY(inflateInit(&d_stream) != Z_OK)) {
		ut_error;
2287
	}
2288

2289 2290 2291
	d_stream.next_in = page_zip->data + PAGE_DATA;
	/* Subtract the space reserved for
	the page header and the end marker of the modification log. */
2292
	d_stream.avail_in = page_zip_get_size(page_zip) - (PAGE_DATA + 1);
2293

2294 2295
	d_stream.next_out = page + PAGE_ZIP_START;
	d_stream.avail_out = UNIV_PAGE_SIZE - PAGE_ZIP_START;
2296

2297 2298 2299
	/* Decode the zlib header and the index information. */
	if (UNIV_UNLIKELY(inflate(&d_stream, Z_BLOCK) != Z_OK)
	    || UNIV_UNLIKELY(inflate(&d_stream, Z_BLOCK) != Z_OK)) {
2300

2301 2302
		goto zlib_error;
	}
2303

2304 2305 2306
	index = page_zip_fields_decode(
		page + PAGE_ZIP_START, d_stream.next_out,
		page_is_leaf(page) ? &trx_id_col : NULL);
2307

2308
	if (UNIV_UNLIKELY(!index)) {
2309

2310 2311
		goto zlib_error;
	}
2312

2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350
	/* Decompress the user records. */
	page_zip->n_blobs = 0;
	d_stream.next_out = page + PAGE_ZIP_START;

	{
		/* Pre-allocate the offsets for rec_get_offsets_reverse(). */
		ulint	n = 1 + 1/* node ptr */ + REC_OFFS_HEADER_SIZE
			+ dict_index_get_n_fields(index);
		offsets = mem_heap_alloc(heap, n * sizeof(ulint));
		*offsets = n;
	}

	/* Decompress the records in heap_no order. */
	if (!page_is_leaf(page)) {
		/* This is a node pointer page. */
		ulint	info_bits;

		if (UNIV_UNLIKELY
		    (!page_zip_decompress_node_ptrs(page_zip, &d_stream,
						    recs, n_dense, index,
						    offsets, heap))) {
			goto err_exit;
		}

		info_bits = mach_read_from_4(page + FIL_PAGE_PREV) == FIL_NULL
			? REC_INFO_MIN_REC_FLAG : 0;

		if (UNIV_UNLIKELY(!page_zip_set_extra_bytes(page_zip, page,
							    info_bits))) {
			goto err_exit;
		}
	} else if (UNIV_LIKELY(trx_id_col == ULINT_UNDEFINED)) {
		/* This is a leaf page in a secondary index. */
		if (UNIV_UNLIKELY(!page_zip_decompress_sec(page_zip, &d_stream,
							   recs, n_dense,
							   index, offsets))) {
			goto err_exit;
		}
2351

2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365 2366 2367
		if (UNIV_UNLIKELY(!page_zip_set_extra_bytes(page_zip,
							    page, 0))) {
err_exit:
			page_zip_fields_free(index);
			mem_heap_free(heap);
			return(FALSE);
		}
	} else {
		/* This is a leaf page in a clustered index. */
		if (UNIV_UNLIKELY(!page_zip_decompress_clust(page_zip,
							     &d_stream, recs,
							     n_dense, index,
							     trx_id_col,
							     offsets, heap))) {
			goto err_exit;
		}
2368

2369 2370 2371 2372
		if (UNIV_UNLIKELY(!page_zip_set_extra_bytes(page_zip,
							    page, 0))) {
			goto err_exit;
		}
2373 2374
	}

marko's avatar
marko committed
2375 2376
	ut_a(page_is_comp(page));

2377 2378 2379
	page_zip_fields_free(index);
	mem_heap_free(heap);

marko's avatar
marko committed
2380 2381 2382
	return(TRUE);
}

2383
#ifdef UNIV_ZIP_DEBUG
2384 2385 2386
/* Flag: make page_zip_validate() compare page headers only */
ibool	page_zip_validate_header_only = FALSE;

marko's avatar
marko committed
2387 2388 2389 2390 2391 2392
/**************************************************************************
Check that the compressed and decompressed pages match. */

ibool
page_zip_validate(
/*==============*/
2393
					/* out: TRUE if valid, FALSE if not */
2394 2395
	const page_zip_des_t*	page_zip,/* in: compressed page */
	const page_t*		page)	/* in: uncompressed page */
marko's avatar
marko committed
2396 2397
{
	page_zip_des_t	temp_page_zip = *page_zip;
2398
	byte*		temp_page_buf;
2399
	page_t*		temp_page;
2400
	ibool		valid;
marko's avatar
marko committed
2401

2402
	ut_a(buf_frame_get_page_zip((byte*) page) == page_zip);
2403
	ut_a(page_is_comp(page));
marko's avatar
marko committed
2404

2405
	if (memcmp(page_zip->data + FIL_PAGE_PREV, page + FIL_PAGE_PREV,
2406
		   FIL_PAGE_LSN - FIL_PAGE_PREV)
2407 2408
	    || memcmp(page_zip->data + FIL_PAGE_TYPE, page + FIL_PAGE_TYPE, 2)
	    || memcmp(page_zip->data + FIL_PAGE_DATA, page + FIL_PAGE_DATA,
2409
		      PAGE_DATA - FIL_PAGE_DATA)) {
2410 2411 2412 2413 2414 2415 2416 2417
		fputs("page_zip_validate(): page header mismatch\n", stderr);
		return(FALSE);
	}

	if (page_zip_validate_header_only) {
		return(TRUE);
	}

2418 2419 2420 2421
	/* page_zip_decompress() expects the uncompressed page to be
	UNIV_PAGE_SIZE aligned. */
	temp_page_buf = ut_malloc(2 * UNIV_PAGE_SIZE);
	temp_page = ut_align(temp_page_buf, UNIV_PAGE_SIZE);
2422

2423
	valid = page_zip_decompress(&temp_page_zip, temp_page);
2424 2425 2426 2427 2428 2429
	if (!valid) {
		fputs("page_zip_validate(): failed to decompress\n", stderr);
		goto func_exit;
	}
	if (page_zip->n_blobs != temp_page_zip.n_blobs) {
		fprintf(stderr,
2430
			"page_zip_validate(): n_blobs mismatch: %d!=%d\n",
2431 2432 2433
			page_zip->n_blobs, temp_page_zip.n_blobs);
		valid = FALSE;
	}
2434
#ifdef UNIV_DEBUG
2435 2436
	if (page_zip->m_start != temp_page_zip.m_start) {
		fprintf(stderr,
2437
			"page_zip_validate(): m_start mismatch: %d!=%d\n",
2438 2439 2440
			page_zip->m_start, temp_page_zip.m_start);
		valid = FALSE;
	}
2441
#endif /* UNIV_DEBUG */
2442 2443
	if (page_zip->m_end != temp_page_zip.m_end) {
		fprintf(stderr,
2444
			"page_zip_validate(): m_end mismatch: %d!=%d\n",
2445 2446 2447
			page_zip->m_end, temp_page_zip.m_end);
		valid = FALSE;
	}
2448 2449 2450 2451 2452 2453
	if (page_zip->m_nonempty != temp_page_zip.m_nonempty) {
		fprintf(stderr,
			"page_zip_validate(): m_nonempty mismatch: %d!=%d\n",
			page_zip->m_nonempty, temp_page_zip.m_nonempty);
		valid = FALSE;
	}
2454
	if (memcmp(page + PAGE_HEADER, temp_page + PAGE_HEADER,
2455
		   UNIV_PAGE_SIZE - PAGE_HEADER - FIL_PAGE_DATA_END)) {
2456
		fputs("page_zip_validate(): content mismatch\n", stderr);
2457 2458 2459 2460
		valid = FALSE;
	}

func_exit:
2461
	ut_free(temp_page_buf);
2462
	return(valid);
marko's avatar
marko committed
2463
}
2464
#endif /* UNIV_ZIP_DEBUG */
marko's avatar
marko committed
2465

2466 2467 2468 2469 2470 2471 2472 2473 2474 2475
#ifdef UNIV_DEBUG
static
ibool
page_zip_header_cmp(
/*================*/
					/* out: TRUE */
	const page_zip_des_t*	page_zip,/* in: compressed page */
	const byte*		page)	/* in: uncompressed page */
{
	ut_ad(!memcmp(page_zip->data + FIL_PAGE_PREV, page + FIL_PAGE_PREV,
2476
		      FIL_PAGE_LSN - FIL_PAGE_PREV));
2477
	ut_ad(!memcmp(page_zip->data + FIL_PAGE_TYPE, page + FIL_PAGE_TYPE,
2478
		      2));
2479
	ut_ad(!memcmp(page_zip->data + FIL_PAGE_DATA, page + FIL_PAGE_DATA,
2480
		      PAGE_DATA - FIL_PAGE_DATA));
2481 2482 2483 2484 2485

	return(TRUE);
}
#endif /* UNIV_DEBUG */

marko's avatar
marko committed
2486
/**************************************************************************
2487
Write an entire record on the compressed page.  The data must already
marko's avatar
marko committed
2488 2489 2490
have been written to the uncompressed page. */

void
2491 2492
page_zip_write_rec(
/*===============*/
marko's avatar
marko committed
2493
	page_zip_des_t*	page_zip,/* in/out: compressed page */
2494
	const byte*	rec,	/* in: record being written */
2495
	dict_index_t*	index,	/* in: the index the record belongs to */
2496 2497
	const ulint*	offsets,/* in: rec_get_offsets(rec, index) */
	ulint		create)	/* in: nonzero=insert, zero=update */
marko's avatar
marko committed
2498
{
2499 2500 2501
	page_t*	page;
	byte*	data;
	byte*	storage;
2502
	ulint	heap_no;
marko's avatar
marko committed
2503
	byte*	slot;
marko's avatar
marko committed
2504

2505
	ut_ad(buf_frame_get_page_zip((byte*) rec) == page_zip);
marko's avatar
marko committed
2506
	ut_ad(page_zip_simple_validate(page_zip));
2507 2508
	ut_ad(page_zip_get_size(page_zip)
	      > PAGE_DATA + page_zip_dir_size(page_zip));
2509
	ut_ad(rec_offs_comp(offsets));
2510
	ut_ad(rec_offs_validate(rec, index, offsets));
marko's avatar
marko committed
2511

2512
	ut_ad(page_zip->m_start >= PAGE_DATA);
marko's avatar
marko committed
2513

2514
	page = page_align((rec_t*) rec);
2515 2516

	ut_ad(page_zip_header_cmp(page_zip, page));
2517
	ut_ad(page_simple_validate_new(page));
2518

2519
	slot = page_zip_dir_find(page_zip, page_offset(rec));
marko's avatar
marko committed
2520
	ut_a(slot);
2521
	/* Copy the delete mark. */
2522
	if (rec_get_deleted_flag(rec, TRUE)) {
2523 2524 2525 2526
		*slot |= PAGE_ZIP_DIR_SLOT_DEL >> 8;
	} else {
		*slot &= ~(PAGE_ZIP_DIR_SLOT_DEL >> 8);
	}
marko's avatar
marko committed
2527

2528 2529
	ut_ad(rec_get_start((rec_t*) rec, offsets) >= page + PAGE_ZIP_START);
	ut_ad(rec_get_end((rec_t*) rec, offsets) <= page + UNIV_PAGE_SIZE
2530 2531
	      - PAGE_DIR - PAGE_DIR_SLOT_SIZE
	      * page_dir_get_n_slots(page));
marko's avatar
marko committed
2532

2533
	heap_no = rec_get_heap_no_new(rec);
2534
	ut_ad(heap_no >= PAGE_HEAP_NO_USER_LOW); /* not infimum or supremum */
2535 2536
	ut_ad(heap_no < page_dir_get_n_heap(page));

marko's avatar
marko committed
2537
	/* Append to the modification log. */
2538
	data = page_zip->data + page_zip->m_end;
2539 2540 2541 2542 2543
	ut_ad(!*data);

	/* Identify the record by writing its heap number - 1.
	0 is reserved to indicate the end of the modification log. */

2544 2545
	if (UNIV_UNLIKELY(heap_no - 1 >= 64)) {
		*data++ = 0x80 | (heap_no - 1) >> 7;
marko's avatar
marko committed
2546
		ut_ad(!*data);
2547
	}
2548
	*data++ = (heap_no - 1) << 1;
marko's avatar
marko committed
2549
	ut_ad(!*data);
2550 2551 2552 2553 2554 2555 2556 2557 2558 2559 2560 2561

	{
		const byte*	start	= rec_get_start((rec_t*) rec, offsets);
		const byte*	b	= rec - REC_N_NEW_EXTRA_BYTES;

		/* Write the extra bytes backwards, so that
		rec_offs_extra_size() can be easily computed in
		page_zip_apply_log() by invoking
		rec_get_offsets_reverse(). */

		while (b != start) {
			*data++ = *--b;
marko's avatar
marko committed
2562
			ut_ad(!*data);
2563 2564 2565 2566
		}
	}

	/* Write the data bytes.  Store the uncompressed bytes separately. */
2567
	storage = page_zip->data + page_zip_get_size(page_zip)
2568
		- (page_dir_get_n_heap(page) - PAGE_HEAP_NO_USER_LOW)
2569
		* PAGE_ZIP_DIR_SLOT_SIZE;
2570 2571 2572

	if (page_is_leaf(page)) {
		ulint		len;
2573
		const byte*	start	= rec;
2574 2575

		if (dict_index_is_clust(index)) {
2576 2577 2578 2579 2580
			ulint		i;
			byte*		externs	= storage;
			ulint		trx_id_col;
			ulint		n_ext	= rec_offs_n_extern(offsets);

2581 2582
			trx_id_col = dict_index_get_sys_col_pos(index,
								DATA_TRX_ID);
2583
			ut_ad(trx_id_col != ULINT_UNDEFINED);
2584

2585
			externs -= (DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN)
2586 2587
				* (page_dir_get_n_heap(page)
				   - PAGE_HEAP_NO_USER_LOW);
2588 2589 2590 2591

			/* Note that this will not take into account
			the BLOB columns of rec if create==TRUE */
			ut_ad(data + rec_offs_data_size(offsets)
2592 2593 2594 2595 2596
			      - (DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN)
			      - n_ext * BTR_EXTERN_FIELD_REF_SIZE
			      < externs
			      - BTR_EXTERN_FIELD_REF_SIZE
			      * page_zip->n_blobs);
2597

2598
			if (UNIV_UNLIKELY(n_ext)) {
2599 2600
				ulint	blob_no = page_zip_get_n_prev_extern(
					page_zip, rec, index);
2601
				byte*	ext_end = externs - page_zip->n_blobs
2602
					* BTR_EXTERN_FIELD_REF_SIZE;
2603 2604 2605 2606 2607
				ut_ad(blob_no <= page_zip->n_blobs);
				externs -= blob_no * BTR_EXTERN_FIELD_REF_SIZE;

				if (create) {
					page_zip->n_blobs += n_ext;
2608 2609 2610 2611 2612
					ut_ad(!memcmp
					      (ext_end - n_ext
					       * BTR_EXTERN_FIELD_REF_SIZE,
					       zero,
					       BTR_EXTERN_FIELD_REF_SIZE));
2613
					memmove(ext_end - n_ext
2614 2615 2616
						* BTR_EXTERN_FIELD_REF_SIZE,
						ext_end,
						externs - ext_end);
2617 2618 2619
				}

				ut_a(blob_no + n_ext <= page_zip->n_blobs);
2620 2621
			}

2622 2623
			/* Store separately trx_id, roll_ptr and
			the BTR_EXTERN_FIELD_REF of each BLOB column. */
2624

2625 2626 2627 2628
			for (i = 0; i < rec_offs_n_fields(offsets); i++) {
				const byte*	src;

				if (UNIV_UNLIKELY(i == trx_id_col)) {
2629 2630 2631 2632
					ut_ad(!rec_offs_nth_extern(offsets,
								   i));
					ut_ad(!rec_offs_nth_extern(offsets,
								   i + 1));
2633
					/* Locate trx_id and roll_ptr. */
2634
					src = rec_get_nth_field(rec, offsets,
2635
								i, &len);
2636 2637
					ut_ad(len == DATA_TRX_ID_LEN);
					ut_ad(src + DATA_TRX_ID_LEN
2638
					      == rec_get_nth_field(
2639
						      rec, offsets,
2640
						      i + 1, &len));
2641 2642 2643
					ut_ad(len == DATA_ROLL_PTR_LEN);

					/* Log the preceding fields. */
2644 2645 2646
					ut_ad(!memcmp(data, zero,
						      ut_min(src - start,
							     sizeof zero)));
2647 2648 2649
					memcpy(data, start, src - start);
					data += src - start;
					start = src + (DATA_TRX_ID_LEN
2650
						       + DATA_ROLL_PTR_LEN);
2651 2652 2653

					/* Store trx_id and roll_ptr. */
					memcpy(storage - (DATA_TRX_ID_LEN
2654 2655 2656 2657
							  + DATA_ROLL_PTR_LEN)
					       * (heap_no - 1),
					       src, DATA_TRX_ID_LEN
					       + DATA_ROLL_PTR_LEN);
2658 2659
					i++; /* skip also roll_ptr */
				} else if (rec_offs_nth_extern(offsets, i)) {
2660
					src = rec_get_nth_field(rec, offsets,
2661
								i, &len);
2662 2663 2664

					ut_ad(dict_index_is_clust(index));
					ut_ad(len
2665
					      >= BTR_EXTERN_FIELD_REF_SIZE);
2666 2667
					src += len - BTR_EXTERN_FIELD_REF_SIZE;

2668 2669 2670
					ut_ad(!memcmp(data, zero,
						      ut_min(src - start,
							     sizeof zero)));
2671 2672 2673 2674
					memcpy(data, start, src - start);
					data += src - start;
					start = src
						+ BTR_EXTERN_FIELD_REF_SIZE;
2675

2676 2677 2678 2679
					/* Store the BLOB pointer. */
					externs -= BTR_EXTERN_FIELD_REF_SIZE;
					ut_ad(data < externs);
					memcpy(externs, src,
2680
					       BTR_EXTERN_FIELD_REF_SIZE);
2681
				}
2682
			}
2683 2684 2685 2686
		} else {
			/* Leaf page of a secondary index:
			no externally stored columns */
			ut_ad(dict_index_get_sys_col_pos(index, DATA_TRX_ID)
2687
			      == ULINT_UNDEFINED);
2688
			ut_ad(!rec_offs_any_extern(offsets));
2689 2690
		}

2691
		/* Log the last bytes of the record. */
2692
		len = rec + rec_offs_data_size(offsets) - start;
2693

marko's avatar
marko committed
2694
		ut_ad(!memcmp(data, zero, ut_min(len, sizeof zero)));
2695 2696 2697 2698 2699 2700 2701 2702 2703 2704 2705 2706
		memcpy(data, start, len);
		data += len;
	} else {
		/* This is a node pointer page. */
		ulint	len;

		/* Non-leaf nodes should not have any externally
		stored columns. */
		ut_ad(!rec_offs_any_extern(offsets));

		/* Copy the data bytes, except node_ptr. */
		len = rec_offs_data_size(offsets) - REC_NODE_PTR_SIZE;
2707
		ut_ad(data + len < storage - REC_NODE_PTR_SIZE
2708
		      * (page_dir_get_n_heap(page) - PAGE_HEAP_NO_USER_LOW));
marko's avatar
marko committed
2709
		ut_ad(!memcmp(data, zero, ut_min(len, sizeof zero)));
2710 2711 2712 2713 2714
		memcpy(data, rec, len);
		data += len;

		/* Copy the node pointer to the uncompressed area. */
		memcpy(storage - REC_NODE_PTR_SIZE
2715 2716 2717
		       * (heap_no - 1),
		       rec + len,
		       REC_NODE_PTR_SIZE);
2718 2719
	}

2720
	ut_a(!*data);
2721
	ut_ad((ulint) (data - page_zip->data) < page_zip_get_size(page_zip));
2722
	page_zip->m_end = data - page_zip->data;
2723
	page_zip->m_nonempty = TRUE;
2724

2725
#ifdef UNIV_ZIP_DEBUG
2726
	ut_a(page_zip_validate(page_zip, page_align((byte*) rec)));
2727
#endif /* UNIV_ZIP_DEBUG */
2728 2729
}

2730 2731 2732 2733 2734 2735 2736 2737 2738 2739 2740 2741 2742 2743 2744 2745 2746
/***************************************************************
Parses a log record of writing a BLOB pointer of a record. */

byte*
page_zip_parse_write_blob_ptr(
/*==========================*/
				/* out: end of log record or NULL */
	byte*		ptr,	/* in: redo log buffer */
	byte*		end_ptr,/* in: redo log buffer end */
	page_t*		page,	/* in/out: uncompressed page */
	page_zip_des_t*	page_zip)/* in/out: compressed page */
{
	ulint	offset;
	ulint	z_offset;

	ut_ad(!page == !page_zip);

2747 2748
	if (UNIV_UNLIKELY
	    (end_ptr < ptr + (2 + 2 + BTR_EXTERN_FIELD_REF_SIZE))) {
2749 2750 2751 2752 2753 2754 2755 2756

		return(NULL);
	}

	offset = mach_read_from_2(ptr);
	z_offset = mach_read_from_2(ptr + 2);

	if (UNIV_UNLIKELY(offset < PAGE_ZIP_START)
2757 2758
	    || UNIV_UNLIKELY(offset >= UNIV_PAGE_SIZE)
	    || UNIV_UNLIKELY(z_offset >= UNIV_PAGE_SIZE)) {
2759 2760 2761 2762 2763 2764 2765
corrupt:
		recv_sys->found_corrupt_log = TRUE;

		return(NULL);
	}

	if (page) {
2766
		if (UNIV_UNLIKELY(!page_zip)
2767
		    || UNIV_UNLIKELY(!page_is_leaf(page))) {
2768 2769 2770 2771

			goto corrupt;
		}

2772
#ifdef UNIV_ZIP_DEBUG
2773
		ut_a(page_zip_validate(page_zip, page));
2774
#endif /* UNIV_ZIP_DEBUG */
2775

2776
		memcpy(page + offset,
2777
		       ptr + 4, BTR_EXTERN_FIELD_REF_SIZE);
2778
		memcpy(page_zip->data + z_offset,
2779
		       ptr + 4, BTR_EXTERN_FIELD_REF_SIZE);
2780

2781
#ifdef UNIV_ZIP_DEBUG
2782
		ut_a(page_zip_validate(page_zip, page));
2783
#endif /* UNIV_ZIP_DEBUG */
2784 2785 2786 2787 2788
	}

	return(ptr + (2 + 2 + BTR_EXTERN_FIELD_REF_SIZE));
}

2789
/**************************************************************************
2790
Write a BLOB pointer of a record on the leaf page of a clustered index.
2791 2792 2793 2794 2795 2796 2797 2798 2799 2800 2801 2802 2803 2804
The information must already have been updated on the uncompressed page. */

void
page_zip_write_blob_ptr(
/*====================*/
	page_zip_des_t*	page_zip,/* in/out: compressed page */
	const byte*	rec,	/* in/out: record whose data is being
				written */
	dict_index_t*	index,	/* in: index of the page */
	const ulint*	offsets,/* in: rec_get_offsets(rec, index) */
	ulint		n,	/* in: column index */
	mtr_t*		mtr)	/* in: mini-transaction handle,
				or NULL if no logging is needed */
{
2805 2806 2807 2808 2809
	const byte*	field;
	byte*		externs;
	page_t*		page	= page_align((byte*) rec);
	ulint		blob_no;
	ulint		len;
2810

2811
	ut_ad(buf_frame_get_page_zip((byte*) rec) == page_zip);
2812
	ut_ad(page_simple_validate_new(page));
2813
	ut_ad(page_zip_simple_validate(page_zip));
2814 2815
	ut_ad(page_zip_get_size(page_zip)
	      > PAGE_DATA + page_zip_dir_size(page_zip));
2816
	ut_ad(rec_offs_comp(offsets));
2817
	ut_ad(rec_offs_validate(rec, NULL, offsets));
2818 2819 2820
	ut_ad(rec_offs_nth_extern(offsets, n));

	ut_ad(page_zip->m_start >= PAGE_DATA);
2821
	ut_ad(page_zip_header_cmp(page_zip, page));
2822 2823

	ut_ad(page_is_leaf(page));
2824
	ut_ad(dict_index_is_clust(index));
2825

2826
	blob_no = page_zip_get_n_prev_extern(page_zip, rec, index)
2827
		+ rec_get_n_extern_new(rec, index, n);
2828
	ut_a(blob_no < page_zip->n_blobs);
2829

2830
	externs = page_zip->data + page_zip_get_size(page_zip)
2831
		- (page_dir_get_n_heap(page) - PAGE_HEAP_NO_USER_LOW)
2832 2833
		* (PAGE_ZIP_DIR_SLOT_SIZE
		   + DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN);
2834

2835
	field = rec_get_nth_field(rec, offsets, n, &len);
2836

2837 2838 2839 2840
	externs -= (blob_no + 1) * BTR_EXTERN_FIELD_REF_SIZE;
	field += len - BTR_EXTERN_FIELD_REF_SIZE;

	memcpy(externs, field, BTR_EXTERN_FIELD_REF_SIZE);
2841

2842
#ifdef UNIV_ZIP_DEBUG
2843
	ut_a(page_zip_validate(page_zip, page_align((rec_t*) rec)));
2844
#endif /* UNIV_ZIP_DEBUG */
2845

2846
	if (mtr) {
2847 2848
		byte*	log_ptr	= mlog_open(
			mtr, 11 + 2 + 2 + BTR_EXTERN_FIELD_REF_SIZE);
2849 2850 2851 2852
		if (UNIV_UNLIKELY(!log_ptr)) {
			return;
		}

2853 2854 2855
		log_ptr = mlog_write_initial_log_record_fast(
			(byte*) field, MLOG_ZIP_WRITE_BLOB_PTR, log_ptr, mtr);
		mach_write_to_2(log_ptr, page_offset(field));
2856
		log_ptr += 2;
2857 2858 2859 2860 2861
		mach_write_to_2(log_ptr, externs - page_zip->data);
		log_ptr += 2;
		memcpy(log_ptr, externs, BTR_EXTERN_FIELD_REF_SIZE);
		log_ptr += BTR_EXTERN_FIELD_REF_SIZE;
		mlog_close(mtr, log_ptr);
2862 2863 2864
	}
}

2865 2866 2867 2868 2869 2870 2871 2872 2873 2874 2875 2876 2877 2878 2879 2880 2881
/***************************************************************
Parses a log record of writing the node pointer of a record. */

byte*
page_zip_parse_write_node_ptr(
/*==========================*/
				/* out: end of log record or NULL */
	byte*		ptr,	/* in: redo log buffer */
	byte*		end_ptr,/* in: redo log buffer end */
	page_t*		page,	/* in/out: uncompressed page */
	page_zip_des_t*	page_zip)/* in/out: compressed page */
{
	ulint	offset;
	ulint	z_offset;

	ut_ad(!page == !page_zip);

2882
	if (UNIV_UNLIKELY(end_ptr < ptr + (2 + 2 + REC_NODE_PTR_SIZE))) {
2883 2884 2885 2886 2887 2888 2889 2890

		return(NULL);
	}

	offset = mach_read_from_2(ptr);
	z_offset = mach_read_from_2(ptr + 2);

	if (UNIV_UNLIKELY(offset < PAGE_ZIP_START)
2891 2892
	    || UNIV_UNLIKELY(offset >= UNIV_PAGE_SIZE)
	    || UNIV_UNLIKELY(z_offset >= UNIV_PAGE_SIZE)) {
2893 2894 2895 2896 2897 2898 2899 2900 2901 2902 2903 2904
corrupt:
		recv_sys->found_corrupt_log = TRUE;

		return(NULL);
	}

	if (page) {
		byte*	storage_end;
		byte*	field;
		byte*	storage;
		ulint	heap_no;

2905
		if (UNIV_UNLIKELY(!page_zip)
2906
		    || UNIV_UNLIKELY(page_is_leaf(page))) {
2907 2908 2909 2910

			goto corrupt;
		}

2911
#ifdef UNIV_ZIP_DEBUG
2912
		ut_a(page_zip_validate(page_zip, page));
2913
#endif /* UNIV_ZIP_DEBUG */
2914

2915 2916 2917
		field = page + offset;
		storage = page_zip->data + z_offset;

2918
		storage_end = page_zip->data + page_zip_get_size(page_zip)
2919
			- (page_dir_get_n_heap(page) - PAGE_HEAP_NO_USER_LOW)
2920 2921 2922 2923 2924
			* PAGE_ZIP_DIR_SLOT_SIZE;

		heap_no = 1 + (storage_end - storage) / REC_NODE_PTR_SIZE;

		if (UNIV_UNLIKELY((storage_end - storage) % REC_NODE_PTR_SIZE)
2925
		    || UNIV_UNLIKELY(heap_no < PAGE_HEAP_NO_USER_LOW)
2926 2927 2928 2929 2930 2931 2932 2933
		    || UNIV_UNLIKELY(heap_no >= page_dir_get_n_heap(page))) {

			goto corrupt;
		}

		memcpy(field, ptr + 4, REC_NODE_PTR_SIZE);
		memcpy(storage, ptr + 4, REC_NODE_PTR_SIZE);

2934
#ifdef UNIV_ZIP_DEBUG
2935
		ut_a(page_zip_validate(page_zip, page));
2936
#endif /* UNIV_ZIP_DEBUG */
2937 2938
	}

2939
	return(ptr + (2 + 2 + REC_NODE_PTR_SIZE));
2940 2941
}

2942 2943 2944 2945 2946 2947 2948 2949 2950 2951 2952 2953 2954 2955
/**************************************************************************
Write the node pointer of a record on a non-leaf compressed page. */

void
page_zip_write_node_ptr(
/*====================*/
	page_zip_des_t*	page_zip,/* in/out: compressed page */
	byte*		rec,	/* in/out: record */
	ulint		size,	/* in: data size of rec */
	ulint		ptr,	/* in: node pointer */
	mtr_t*		mtr)	/* in: mini-transaction, or NULL */
{
	byte*	field;
	byte*	storage;
2956
	page_t*	page	= page_align(rec);
2957

2958
	ut_ad(buf_frame_get_page_zip(rec) == page_zip);
2959
	ut_ad(page_simple_validate_new(page));
2960
	ut_ad(page_zip_simple_validate(page_zip));
2961 2962
	ut_ad(page_zip_get_size(page_zip)
	      > PAGE_DATA + page_zip_dir_size(page_zip));
2963 2964 2965
	ut_ad(page_rec_is_comp(rec));

	ut_ad(page_zip->m_start >= PAGE_DATA);
2966
	ut_ad(page_zip_header_cmp(page_zip, page));
2967 2968 2969

	ut_ad(!page_is_leaf(page));

2970
	storage = page_zip->data + page_zip_get_size(page_zip)
2971
		- (page_dir_get_n_heap(page) - PAGE_HEAP_NO_USER_LOW)
2972 2973
		* PAGE_ZIP_DIR_SLOT_SIZE
		- (rec_get_heap_no_new(rec) - 1) * REC_NODE_PTR_SIZE;
2974 2975
	field = rec + size - REC_NODE_PTR_SIZE;

2976
#if defined UNIV_DEBUG || defined UNIV_ZIP_DEBUG
2977
	ut_a(!memcmp(storage, field, REC_NODE_PTR_SIZE));
2978
#endif /* UNIV_DEBUG || UNIV_ZIP_DEBUG */
2979 2980 2981 2982 2983 2984 2985
#if REC_NODE_PTR_SIZE != 4
# error "REC_NODE_PTR_SIZE != 4"
#endif
	mach_write_to_4(field, ptr);
	memcpy(storage, field, REC_NODE_PTR_SIZE);

	if (mtr) {
2986
		byte*	log_ptr	= mlog_open(mtr,
2987
					    11 + 2 + 2 + REC_NODE_PTR_SIZE);
2988 2989 2990 2991
		if (UNIV_UNLIKELY(!log_ptr)) {
			return;
		}

2992 2993 2994
		log_ptr = mlog_write_initial_log_record_fast(
			field, MLOG_ZIP_WRITE_NODE_PTR, log_ptr, mtr);
		mach_write_to_2(log_ptr, page_offset(field));
2995
		log_ptr += 2;
2996 2997
		mach_write_to_2(log_ptr, storage - page_zip->data);
		log_ptr += 2;
2998
		memcpy(log_ptr, field, REC_NODE_PTR_SIZE);
2999 3000
		log_ptr += REC_NODE_PTR_SIZE;
		mlog_close(mtr, log_ptr);
3001
	}
marko's avatar
marko committed
3002 3003 3004
}

/**************************************************************************
3005
Write the trx_id and roll_ptr of a record on a B-tree leaf node page. */
marko's avatar
marko committed
3006

3007
void
3008 3009
page_zip_write_trx_id_and_roll_ptr(
/*===============================*/
3010 3011
	page_zip_des_t*	page_zip,/* in/out: compressed page */
	byte*		rec,	/* in/out: record */
3012 3013
	const ulint*	offsets,/* in: rec_get_offsets(rec, index) */
	ulint		trx_id_col,/* in: column number of TRX_ID in rec */
3014
	dulint		trx_id,	/* in: transaction identifier */
3015
	dulint		roll_ptr)/* in: roll_ptr */
marko's avatar
marko committed
3016
{
3017 3018
	byte*	field;
	byte*	storage;
3019
	page_t*	page	= page_align(rec);
3020
	ulint	len;
3021

3022
	ut_ad(buf_frame_get_page_zip(rec) == page_zip);
3023
	ut_ad(page_simple_validate_new(page));
3024
	ut_ad(page_zip_simple_validate(page_zip));
3025 3026
	ut_ad(page_zip_get_size(page_zip)
	      > PAGE_DATA + page_zip_dir_size(page_zip));
3027 3028
	ut_ad(rec_offs_validate(rec, NULL, offsets));
	ut_ad(rec_offs_comp(offsets));
3029 3030

	ut_ad(page_zip->m_start >= PAGE_DATA);
3031
	ut_ad(page_zip_header_cmp(page_zip, page));
3032 3033 3034

	ut_ad(page_is_leaf(page));

3035
	storage = page_zip->data + page_zip_get_size(page_zip)
3036
		- (page_dir_get_n_heap(page) - PAGE_HEAP_NO_USER_LOW)
3037 3038 3039
		* PAGE_ZIP_DIR_SLOT_SIZE
		- (rec_get_heap_no_new(rec) - 1)
		* (DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN);
3040 3041 3042 3043 3044 3045 3046

#if DATA_TRX_ID + 1 != DATA_ROLL_PTR
# error "DATA_TRX_ID + 1 != DATA_ROLL_PTR"
#endif
	field = rec_get_nth_field(rec, offsets, trx_id_col, &len);
	ut_ad(len == DATA_TRX_ID_LEN);
	ut_ad(field + DATA_TRX_ID_LEN
3047
	      == rec_get_nth_field(rec, offsets, trx_id_col + 1, &len));
3048
	ut_ad(len == DATA_ROLL_PTR_LEN);
3049 3050 3051 3052 3053 3054 3055 3056 3057 3058
#if defined UNIV_DEBUG || defined UNIV_ZIP_DEBUG
	ut_a(!memcmp(storage, field, DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN));
#endif /* UNIV_DEBUG || UNIV_ZIP_DEBUG */
#if DATA_TRX_ID_LEN != 6
# error "DATA_TRX_ID_LEN != 6"
#endif
	mach_write_to_6(field, trx_id);
#if DATA_ROLL_PTR_LEN != 7
# error "DATA_ROLL_PTR_LEN != 7"
#endif
marko's avatar
marko committed
3059
	mach_write_to_7(field + DATA_TRX_ID_LEN, roll_ptr);
3060
	memcpy(storage, field, DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN);
3061 3062
}

3063 3064 3065
#ifdef UNIV_ZIP_DEBUG
/* Set this variable in a debugger to disable page_zip_clear_rec().
The only observable effect should be the compression ratio due to
3066 3067 3068
deleted records not being zeroed out.  In rare cases, there can be
page_zip_validate() failures on the node_ptr, trx_id and roll_ptr
columns if the space is reallocated for a smaller record. */
3069 3070 3071
ibool	page_zip_clear_rec_disable;
#endif /* UNIV_ZIP_DEBUG */

3072 3073
/**************************************************************************
Clear an area on the uncompressed and compressed page, if possible. */
3074
static
3075 3076 3077 3078 3079 3080
void
page_zip_clear_rec(
/*===============*/
	page_zip_des_t*	page_zip,/* in/out: compressed page */
	byte*		rec,	/* in: record to clear */
	dict_index_t*	index,	/* in: index of rec */
3081
	const ulint*	offsets)/* in: rec_get_offsets(rec, index) */
3082
{
3083
	ulint	heap_no;
3084
	page_t*	page	= page_align(rec);
3085 3086
	/* page_zip_validate() would fail here if a record
	containing externally stored columns is being deleted. */
3087
	ut_ad(rec_offs_validate(rec, index, offsets));
3088 3089
	ut_ad(!page_zip_dir_find(page_zip, page_offset(rec)));
	ut_ad(page_zip_dir_find_free(page_zip, page_offset(rec)));
3090
	ut_ad(page_zip_header_cmp(page_zip, page));
3091

3092
	heap_no = rec_get_heap_no_new(rec);
3093
	ut_ad(heap_no >= PAGE_HEAP_NO_USER_LOW);
3094

3095 3096
	if (
#ifdef UNIV_ZIP_DEBUG
3097
	    !page_zip_clear_rec_disable &&
3098
#endif /* UNIV_ZIP_DEBUG */
3099 3100 3101
	    page_zip->m_end
	    + 1 + ((heap_no - 1) >= 64)/* size of the log entry */
	    + page_zip_get_trailer_len(page_zip, index, NULL)
3102
	    < page_zip_get_size(page_zip)) {
3103
		byte*	data;
3104 3105 3106

		/* Clear only the data bytes, because the allocator and
		the decompressor depend on the extra bytes. */
3107 3108
		memset(rec, 0, rec_offs_data_size(offsets));

marko's avatar
marko committed
3109 3110
		if (!page_is_leaf(page)) {
			/* Clear node_ptr on the compressed page. */
3111 3112
			byte*	storage	= page_zip->data
				+ page_zip_get_size(page_zip)
3113 3114
				- (page_dir_get_n_heap(page)
				   - PAGE_HEAP_NO_USER_LOW)
3115
				* PAGE_ZIP_DIR_SLOT_SIZE;
marko's avatar
marko committed
3116 3117

			memset(storage - (heap_no - 1) * REC_NODE_PTR_SIZE,
3118
			       0, REC_NODE_PTR_SIZE);
3119
		} else if (dict_index_is_clust(index)) {
3120
			/* Clear trx_id and roll_ptr on the compressed page. */
3121 3122
			byte*	storage	= page_zip->data
				+ page_zip_get_size(page_zip)
3123 3124
				- (page_dir_get_n_heap(page)
				   - PAGE_HEAP_NO_USER_LOW)
3125
				* PAGE_ZIP_DIR_SLOT_SIZE;
3126 3127

			memset(storage - (heap_no - 1)
3128 3129
			       * (DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN),
			       0, DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN);
3130 3131
		}

3132
		/* Log that the data was zeroed out. */
3133 3134 3135 3136
		data = page_zip->data + page_zip->m_end;
		ut_ad(!*data);
		if (UNIV_UNLIKELY(heap_no - 1 >= 64)) {
			*data++ = 0x80 | (heap_no - 1) >> 7;
marko's avatar
marko committed
3137
			ut_ad(!*data);
3138 3139 3140
		}
		*data++ = (heap_no - 1) << 1 | 1;
		ut_ad(!*data);
3141 3142
		ut_ad((ulint) (data - page_zip->data)
		      < page_zip_get_size(page_zip));
3143
		page_zip->m_end = data - page_zip->data;
3144
		page_zip->m_nonempty = TRUE;
3145
	} else if (page_is_leaf(page) && dict_index_is_clust(index)) {
marko's avatar
marko committed
3146 3147 3148 3149 3150 3151 3152 3153 3154
		/* Do not clear the record, because there is not enough space
		to log the operation. */

		ulint	i;
		for (i = rec_offs_n_fields(offsets); i--; ) {
			/* Clear all BLOB pointers in order to make
			page_zip_validate() pass. */
			if (rec_offs_nth_extern(offsets, i)) {
				ulint	len;
3155 3156
				byte*	field = rec_get_nth_field(rec, offsets,
								  i, &len);
marko's avatar
marko committed
3157
				memset(field + len - BTR_EXTERN_FIELD_REF_SIZE,
3158
				       0, BTR_EXTERN_FIELD_REF_SIZE);
marko's avatar
marko committed
3159
			}
3160 3161
		}
	}
marko's avatar
marko committed
3162 3163 3164 3165

#ifdef UNIV_ZIP_DEBUG
	ut_a(page_zip_validate(page_zip, page));
#endif /* UNIV_ZIP_DEBUG */
3166 3167 3168 3169 3170 3171 3172 3173 3174 3175 3176 3177 3178
}

/**************************************************************************
Write the "deleted" flag of a record on a compressed page.  The flag must
already have been written on the uncompressed page. */

void
page_zip_rec_set_deleted(
/*=====================*/
	page_zip_des_t*	page_zip,/* in/out: compressed page */
	const byte*	rec,	/* in: record on the uncompressed page */
	ulint		flag)	/* in: the deleted flag (nonzero=TRUE) */
{
3179
	byte*	slot = page_zip_dir_find(page_zip, page_offset(rec));
3180 3181 3182 3183 3184 3185 3186 3187 3188 3189 3190 3191 3192 3193 3194 3195 3196 3197 3198
	ut_a(slot);
	if (flag) {
		*slot |= (PAGE_ZIP_DIR_SLOT_DEL >> 8);
	} else {
		*slot &= ~(PAGE_ZIP_DIR_SLOT_DEL >> 8);
	}
}

/**************************************************************************
Write the "owned" flag of a record on a compressed page.  The n_owned field
must already have been written on the uncompressed page. */

void
page_zip_rec_set_owned(
/*===================*/
	page_zip_des_t*	page_zip,/* in/out: compressed page */
	const byte*	rec,	/* in: record on the uncompressed page */
	ulint		flag)	/* in: the owned flag (nonzero=TRUE) */
{
3199
	byte*	slot = page_zip_dir_find(page_zip, page_offset(rec));
3200 3201 3202 3203 3204 3205 3206 3207
	ut_a(slot);
	if (flag) {
		*slot |= (PAGE_ZIP_DIR_SLOT_OWNED >> 8);
	} else {
		*slot &= ~(PAGE_ZIP_DIR_SLOT_OWNED >> 8);
	}
}

3208 3209 3210 3211 3212 3213 3214 3215 3216 3217
/**************************************************************************
Insert a record to the dense page directory. */

void
page_zip_dir_insert(
/*================*/
	page_zip_des_t*	page_zip,/* in/out: compressed page */
	const byte*	prev_rec,/* in: record after which to insert */
	const byte*	free_rec,/* in: record from which rec was
				allocated, or NULL */
3218
	byte*		rec)	/* in: record to insert */
3219 3220 3221 3222 3223 3224 3225
{
	ulint	n_dense;
	byte*	slot_rec;
	byte*	slot_free;

	ut_ad(prev_rec != rec);
	ut_ad(page_rec_get_next((rec_t*) prev_rec) == rec);
3226
	ut_ad(page_zip_simple_validate(page_zip));
3227 3228 3229

	if (page_rec_is_infimum(prev_rec)) {
		/* Use the first slot. */
3230
		slot_rec = page_zip->data + page_zip_get_size(page_zip);
3231
	} else {
3232
		byte*	end	= page_zip->data + page_zip_get_size(page_zip);
3233 3234 3235 3236 3237 3238 3239 3240 3241 3242
		byte*	start	= end - page_zip_dir_user_size(page_zip);

		if (UNIV_LIKELY(!free_rec)) {
			/* PAGE_N_RECS was already incremented
			in page_cur_insert_rec_low(), but the
			dense directory slot at that position
			contains garbage.  Skip it. */
			start += PAGE_ZIP_DIR_SLOT_SIZE;
		}

3243 3244
		slot_rec = page_zip_dir_find_low(start, end,
						 page_offset(prev_rec));
3245 3246 3247
		ut_a(slot_rec);
	}

3248 3249 3250
	/* Read the old n_dense (n_heap may have been incremented). */
	n_dense = page_dir_get_n_heap(page_zip->data)
		- (PAGE_HEAP_NO_USER_LOW + 1);
3251 3252 3253 3254 3255 3256 3257 3258

	if (UNIV_LIKELY_NULL(free_rec)) {
		/* The record was allocated from the free list.
		Shift the dense directory only up to that slot.
		Note that in this case, n_dense is actually
		off by one, because page_cur_insert_rec_low()
		did not increment n_heap. */
		ut_ad(rec_get_heap_no_new(rec) < n_dense + 1
3259
		      + PAGE_HEAP_NO_USER_LOW);
3260
		ut_ad(rec >= free_rec);
3261
		slot_free = page_zip_dir_find(page_zip, page_offset(free_rec));
3262 3263 3264 3265 3266 3267
		ut_ad(slot_free);
		slot_free += PAGE_ZIP_DIR_SLOT_SIZE;
	} else {
		/* The record was allocated from the heap.
		Shift the entire dense directory. */
		ut_ad(rec_get_heap_no_new(rec) == n_dense
3268
		      + PAGE_HEAP_NO_USER_LOW);
3269 3270

		/* Shift to the end of the dense page directory. */
3271
		slot_free = page_zip->data + page_zip_get_size(page_zip)
3272
			- PAGE_ZIP_DIR_SLOT_SIZE * n_dense;
3273 3274 3275 3276
	}

	/* Shift the dense directory to allocate place for rec. */
	memmove(slot_free - PAGE_ZIP_DIR_SLOT_SIZE, slot_free,
3277
		slot_rec - slot_free);
3278 3279 3280

	/* Write the entry for the inserted record.
	The "owned" and "deleted" flags must be zero. */
3281
	mach_write_to_2(slot_rec - PAGE_ZIP_DIR_SLOT_SIZE, page_offset(rec));
3282 3283
}

3284
/**************************************************************************
3285 3286
Shift the dense page directory and the array of BLOB pointers
when a record is deleted. */
3287 3288 3289 3290 3291

void
page_zip_dir_delete(
/*================*/
	page_zip_des_t*	page_zip,/* in/out: compressed page */
3292 3293 3294
	byte*		rec,	/* in: record to delete */
	dict_index_t*	index,	/* in: index of rec */
	const ulint*	offsets,/* in: rec_get_offsets(rec) */
3295 3296 3297 3298
	const byte*	free)	/* in: previous start of the free list */
{
	byte*	slot_rec;
	byte*	slot_free;
3299
	ulint	n_ext;
3300
	page_t*	page	= page_align(rec);
3301

3302 3303
	ut_ad(rec_offs_validate(rec, index, offsets));
	ut_ad(rec_offs_comp(offsets));
marko's avatar
marko committed
3304

3305
	slot_rec = page_zip_dir_find(page_zip, page_offset(rec));
3306 3307 3308

	ut_a(slot_rec);

3309 3310
	/* This could not be done before page_zip_dir_find(). */
	page_header_set_field(page, page_zip, PAGE_N_RECS,
3311
			      (ulint)(page_get_n_recs(page) - 1));
3312

marko's avatar
marko committed
3313
	if (UNIV_UNLIKELY(!free)) {
3314
		/* Make the last slot the start of the free list. */
3315
		slot_free = page_zip->data + page_zip_get_size(page_zip)
3316
			- PAGE_ZIP_DIR_SLOT_SIZE
3317 3318
			* (page_dir_get_n_heap(page_zip->data)
			   - PAGE_HEAP_NO_USER_LOW);
3319
	} else {
3320 3321
		slot_free = page_zip_dir_find_free(page_zip,
						   page_offset(free));
3322 3323 3324 3325 3326
		ut_a(slot_free < slot_rec);
		/* Grow the free list by one slot by moving the start. */
		slot_free += PAGE_ZIP_DIR_SLOT_SIZE;
	}

marko's avatar
marko committed
3327
	if (UNIV_LIKELY(slot_rec > slot_free)) {
3328 3329
		memmove(slot_free + PAGE_ZIP_DIR_SLOT_SIZE,
			slot_free,
marko's avatar
marko committed
3330
			slot_rec - slot_free);
3331 3332 3333 3334
	}

	/* Write the entry for the deleted record.
	The "owned" and "deleted" flags will be cleared. */
3335
	mach_write_to_2(slot_free, page_offset(rec));
3336

3337 3338 3339 3340 3341
	if (!page_is_leaf(page) || !dict_index_is_clust(index)) {
		ut_ad(!rec_offs_any_extern(offsets));
		goto skip_blobs;
	}

3342 3343 3344 3345 3346 3347 3348 3349 3350 3351
	n_ext = rec_offs_n_extern(offsets);
	if (UNIV_UNLIKELY(n_ext)) {
		/* Shift and zero fill the array of BLOB pointers. */
		ulint	blob_no;
		byte*	externs;
		byte*	ext_end;

		blob_no = page_zip_get_n_prev_extern(page_zip, rec, index);
		ut_a(blob_no + n_ext <= page_zip->n_blobs);

3352
		externs = page_zip->data + page_zip_get_size(page_zip)
3353
			- (page_dir_get_n_heap(page) - PAGE_HEAP_NO_USER_LOW)
3354 3355
			* (PAGE_ZIP_DIR_SLOT_SIZE
			   + DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN);
3356 3357

		ext_end = externs - page_zip->n_blobs
3358
			* BTR_EXTERN_FIELD_REF_SIZE;
3359 3360 3361 3362 3363
		externs -= blob_no * BTR_EXTERN_FIELD_REF_SIZE;

		page_zip->n_blobs -= n_ext;
		/* Shift and zero fill the array. */
		memmove(ext_end + n_ext * BTR_EXTERN_FIELD_REF_SIZE, ext_end,
3364 3365
			(page_zip->n_blobs - blob_no)
			* BTR_EXTERN_FIELD_REF_SIZE);
3366 3367 3368
		memset(ext_end, 0, n_ext * BTR_EXTERN_FIELD_REF_SIZE);
	}

3369
skip_blobs:
3370 3371 3372 3373
	/* The compression algorithm expects info_bits and n_owned
	to be 0 for deleted records. */
	rec[-REC_N_NEW_EXTRA_BYTES] = 0; /* info_bits and n_owned */

3374
	page_zip_clear_rec(page_zip, rec, index, offsets);
marko's avatar
marko committed
3375
}
3376

3377 3378 3379 3380 3381 3382
/**************************************************************************
Add a slot to the dense page directory. */

void
page_zip_dir_add_slot(
/*==================*/
3383 3384 3385
	page_zip_des_t*	page_zip,	/* in/out: compressed page */
	ulint		is_clustered)	/* in: nonzero for clustered index,
					zero for others */
3386 3387 3388 3389 3390
{
	ulint	n_dense;
	byte*	dir;
	byte*	stored;

3391 3392
	ut_ad(page_is_comp(page_zip->data));

3393 3394 3395
	/* Read the old n_dense (n_heap has already been incremented). */
	n_dense = page_dir_get_n_heap(page_zip->data)
		- (PAGE_HEAP_NO_USER_LOW + 1);
3396

3397
	dir = page_zip->data + page_zip_get_size(page_zip)
3398
		- PAGE_ZIP_DIR_SLOT_SIZE * n_dense;
3399

3400 3401 3402 3403
	if (!page_is_leaf(page_zip->data)) {
		ut_ad(!page_zip->n_blobs);
		stored = dir - n_dense * REC_NODE_PTR_SIZE;
	} else if (UNIV_UNLIKELY(is_clustered)) {
3404 3405 3406 3407
		/* Move the BLOB pointer array backwards to make space for the
		roll_ptr and trx_id columns and the dense directory slot. */
		byte*	externs;

3408
		stored = dir - n_dense
3409 3410
			* (DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN);
		externs = stored
3411
			- page_zip->n_blobs * BTR_EXTERN_FIELD_REF_SIZE;
3412 3413 3414 3415 3416
		ut_ad(!memcmp(zero, externs
			      - (PAGE_ZIP_DIR_SLOT_SIZE
				 + DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN),
			      PAGE_ZIP_DIR_SLOT_SIZE
			      + DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN));
3417
		memmove(externs - (PAGE_ZIP_DIR_SLOT_SIZE
3418
				   + DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN),
3419
			externs, stored - externs);
3420
	} else {
3421 3422
		stored = dir
			- page_zip->n_blobs * BTR_EXTERN_FIELD_REF_SIZE;
marko's avatar
marko committed
3423
		ut_ad(!memcmp(zero, stored - PAGE_ZIP_DIR_SLOT_SIZE,
3424
			      PAGE_ZIP_DIR_SLOT_SIZE));
3425 3426
	}

3427 3428 3429
	/* Move the uncompressed area backwards to make space
	for one directory slot. */
	memmove(stored - PAGE_ZIP_DIR_SLOT_SIZE, stored, dir - stored);
3430 3431
}

3432 3433 3434 3435 3436 3437 3438 3439 3440 3441 3442 3443 3444 3445 3446
/***************************************************************
Parses a log record of writing to the header of a page. */

byte*
page_zip_parse_write_header(
/*========================*/
				/* out: end of log record or NULL */
	byte*		ptr,	/* in: redo log buffer */
	byte*		end_ptr,/* in: redo log buffer end */
	page_t*		page,	/* in/out: uncompressed page */
	page_zip_des_t*	page_zip)/* in/out: compressed page */
{
	ulint	offset;
	ulint	len;

3447
	ut_ad(ptr && end_ptr);
3448 3449
	ut_ad(!page == !page_zip);

3450
	if (UNIV_UNLIKELY(end_ptr < ptr + (1 + 1))) {
3451 3452 3453 3454

		return(NULL);
	}

3455
	offset = (ulint) *ptr++;
3456 3457
	len = (ulint) *ptr++;

3458 3459
	if (UNIV_UNLIKELY(!len) || UNIV_UNLIKELY(offset + len >= PAGE_DATA)) {
corrupt:
3460 3461 3462 3463 3464 3465 3466 3467 3468 3469 3470
		recv_sys->found_corrupt_log = TRUE;

		return(NULL);
	}

	if (UNIV_UNLIKELY(end_ptr < ptr + len)) {

		return(NULL);
	}

	if (page) {
3471 3472 3473 3474
		if (UNIV_UNLIKELY(!page_zip)) {

			goto corrupt;
		}
3475
#ifdef UNIV_ZIP_DEBUG
3476
		ut_a(page_zip_validate(page_zip, page));
3477
#endif /* UNIV_ZIP_DEBUG */
3478 3479 3480 3481

		memcpy(page + offset, ptr, len);
		memcpy(page_zip->data + offset, ptr, len);

3482
#ifdef UNIV_ZIP_DEBUG
3483
		ut_a(page_zip_validate(page_zip, page));
3484
#endif /* UNIV_ZIP_DEBUG */
3485 3486 3487 3488 3489
	}

	return(ptr + len);
}

3490 3491 3492 3493 3494 3495
/**************************************************************************
Write a log record of writing to the uncompressed header portion of a page. */

void
page_zip_write_header_log(
/*======================*/
3496 3497 3498
	const byte*	data,	/* in: data on the uncompressed page */
	ulint		length,	/* in: length of the data */
	mtr_t*		mtr)	/* in: mini-transaction */
3499
{
3500
	byte*	log_ptr	= mlog_open(mtr, 11 + 1 + 1);
3501
	ulint	offset	= page_offset(data);
3502

3503 3504 3505 3506 3507 3508 3509 3510
	ut_ad(offset < PAGE_DATA);
	ut_ad(offset + length < PAGE_DATA);
#if PAGE_DATA > 255
# error "PAGE_DATA > 255"
#endif
	ut_ad(length < 256);

	/* If no logging is requested, we may return now */
3511
	if (UNIV_UNLIKELY(!log_ptr)) {
3512 3513 3514 3515

		return;
	}

3516 3517
	log_ptr = mlog_write_initial_log_record_fast(
		(byte*) data, MLOG_ZIP_WRITE_HEADER, log_ptr, mtr);
3518
	*log_ptr++ = (byte) offset;
3519
	*log_ptr++ = (byte) length;
3520 3521
	mlog_close(mtr, log_ptr);

3522
	mlog_catenate_string(mtr, data, length);
3523
}
3524

3525 3526 3527
/**************************************************************************
Reorganize and compress a page.  This is a low-level operation for
compressed pages, to be used when page_zip_compress() fails.
3528
On success, a redo log entry MLOG_ZIP_PAGE_COMPRESS will be written.
3529 3530 3531 3532 3533 3534 3535 3536
The function btr_page_reorganize() should be preferred whenever possible. */

ibool
page_zip_reorganize(
/*================*/
				/* out: TRUE on success, FALSE on failure;
				page and page_zip will be left intact
				on failure. */
3537 3538
	buf_block_t*	block,	/* in/out: page with compressed page;
				on the compressed page, in: size;
3539 3540
				out: data, n_blobs,
				m_start, m_end, m_nonempty */
3541 3542 3543
	dict_index_t*	index,	/* in: index of the B-tree node */
	mtr_t*		mtr)	/* in: mini-transaction */
{
3544 3545
	page_zip_des_t*	page_zip	= buf_block_get_page_zip(block);
	page_t*		page		= buf_block_get_frame(block);
3546
	buf_block_t*	temp_block;
3547 3548
	page_t*		temp_page;
	ulint		log_mode;
3549

marko's avatar
marko committed
3550
	ut_ad(mtr_memo_contains(mtr, block, MTR_MEMO_PAGE_X_FIX));
3551 3552 3553 3554 3555 3556
	ut_ad(page_is_comp(page));
	/* Note that page_zip_validate(page_zip, page) may fail here. */

	/* Disable logging */
	log_mode = mtr_set_log_mode(mtr, MTR_LOG_NONE);

3557 3558
	temp_block = buf_block_alloc(0);
	temp_page = temp_block->frame;
3559 3560 3561 3562 3563 3564 3565

	/* Copy the old page to temporary space */
	buf_frame_copy(temp_page, page);

	/* Recreate the page: note that global data on page (possible
	segment headers, next page-field, etc.) is preserved intact */

3566
	page_create(block, mtr, dict_table_is_comp(index->table));
3567
	block->check_index_page_at_flush = TRUE;
3568 3569 3570 3571

	/* Copy the records from the temporary space to the recreated page;
	do not copy the lock bits yet */

3572 3573
	page_copy_rec_list_end_no_locks(block, temp_block,
					page_get_infimum_rec(temp_page),
3574
					index, mtr);
3575
	/* Copy max trx id to recreated page */
marko's avatar
marko committed
3576
	page_set_max_trx_id(block, NULL, page_get_max_trx_id(temp_page));
3577

3578 3579 3580
	/* Restore logging. */
	mtr_set_log_mode(mtr, log_mode);

3581 3582 3583 3584 3585
	if (UNIV_UNLIKELY(!page_zip_compress(page_zip, page, index, mtr))) {

		/* Restore the old page and exit. */
		buf_frame_copy(page, temp_page);

3586
		buf_block_free(temp_block);
3587 3588 3589
		return(FALSE);
	}

3590
	lock_move_reorganize_page(block, temp_block);
3591
	btr_search_drop_page_hash_index(block);
3592

3593
	buf_block_free(temp_block);
3594 3595 3596
	return(TRUE);
}

3597 3598 3599 3600 3601 3602
/**************************************************************************
Copy a page byte for byte, except for the file page header and trailer. */

void
page_zip_copy(
/*==========*/
3603 3604
	page_zip_des_t*		page_zip,	/* out: copy of src_zip
						(n_blobs, m_start, m_end,
3605
						m_nonempty, data[0..size-1]) */
3606 3607 3608
	page_t*			page,		/* out: copy of src */
	const page_zip_des_t*	src_zip,	/* in: compressed page */
	const page_t*		src,		/* in: page */
3609
	dict_index_t*		index,		/* in: index of the B-tree */
3610 3611
	mtr_t*			mtr)		/* in: mini-transaction */
{
3612 3613
	ut_ad(mtr_memo_contains_page(mtr, page, MTR_MEMO_PAGE_X_FIX));
	ut_ad(mtr_memo_contains_page(mtr, (page_t*) src, MTR_MEMO_PAGE_X_FIX));
3614
#ifdef UNIV_ZIP_DEBUG
3615
	ut_a(page_zip_validate(src_zip, src));
3616
#endif /* UNIV_ZIP_DEBUG */
3617
	ut_a(page_zip_get_size(page_zip) == page_zip_get_size(src_zip));
3618
	if (UNIV_UNLIKELY(src_zip->n_blobs)) {
3619
		ut_a(page_is_leaf(src));
3620 3621
		ut_a(dict_index_is_clust(index));
	}
3622 3623 3624

	/* Skip the file page header and trailer. */
	memcpy(page + FIL_PAGE_DATA, src + FIL_PAGE_DATA,
3625 3626
	       UNIV_PAGE_SIZE - FIL_PAGE_DATA
	       - FIL_PAGE_DATA_END);
3627
	memcpy(page_zip->data + FIL_PAGE_DATA,
3628
	       src_zip->data + FIL_PAGE_DATA,
3629
	       page_zip_get_size(page_zip) - FIL_PAGE_DATA);
3630

3631 3632 3633 3634 3635
	{
		page_zip_t*	data = page_zip->data;
		memcpy(page_zip, src_zip, sizeof *page_zip);
		page_zip->data = data;
	}
3636
	ut_ad(page_zip_get_trailer_len(page_zip, index, NULL)
3637
	      + page_zip->m_end < page_zip_get_size(page_zip));
3638

3639
	if (!page_is_leaf(src)
3640
	    && UNIV_UNLIKELY(mach_read_from_4(src + FIL_PAGE_PREV) == FIL_NULL)
3641 3642
	    && UNIV_LIKELY(mach_read_from_4(page
					    + FIL_PAGE_PREV) != FIL_NULL)) {
3643
		/* Clear the REC_INFO_MIN_REC_FLAG of the first user record. */
3644 3645
		ulint	offs = rec_get_next_offs(page + PAGE_NEW_INFIMUM,
						 TRUE);
3646 3647 3648
		if (UNIV_LIKELY(offs != PAGE_NEW_SUPREMUM)) {
			rec_t*	rec = page + offs;
			ut_a(rec[-REC_N_NEW_EXTRA_BYTES]
3649
			     & REC_INFO_MIN_REC_FLAG);
3650 3651 3652 3653
			rec[-REC_N_NEW_EXTRA_BYTES] &= ~ REC_INFO_MIN_REC_FLAG;
		}
	}

3654
#ifdef UNIV_ZIP_DEBUG
3655
	ut_a(page_zip_validate(page_zip, page));
3656
#endif /* UNIV_ZIP_DEBUG */
3657

3658
	page_zip_compress_write_log(page_zip, page, index, mtr);
3659 3660
}

3661 3662 3663 3664 3665 3666 3667 3668 3669 3670 3671 3672 3673
/**************************************************************************
Parses a log record of compressing an index page. */

byte*
page_zip_parse_compress(
/*====================*/
				/* out: end of log record or NULL */
	byte*		ptr,	/* in: buffer */
	byte*		end_ptr,/* in: buffer end */
	page_t*		page,	/* out: uncompressed page */
	page_zip_des_t*	page_zip)/* out: compressed page */
{
	ulint	size;
3674
	ulint	trailer_size;
3675 3676

	ut_ad(ptr && end_ptr);
3677
	ut_ad(!page == !page_zip);
3678

3679
	if (UNIV_UNLIKELY(ptr + (2 + 2) > end_ptr)) {
3680 3681 3682 3683 3684 3685

		return(NULL);
	}

	size = mach_read_from_2(ptr);
	ptr += 2;
3686 3687
	trailer_size = mach_read_from_2(ptr);
	ptr += 2;
3688

3689
	if (UNIV_UNLIKELY(ptr + 8 + size + trailer_size > end_ptr)) {
3690 3691 3692 3693 3694 3695

		return(NULL);
	}

	if (page) {
		if (UNIV_UNLIKELY(!page_zip)
3696
		    || UNIV_UNLIKELY(page_zip_get_size(page_zip) < size)) {
3697 3698 3699 3700 3701 3702
corrupt:
			recv_sys->found_corrupt_log = TRUE;

			return(NULL);
		}

3703 3704 3705 3706
		memcpy(page_zip->data + FIL_PAGE_PREV, ptr, 4);
		memcpy(page_zip->data + FIL_PAGE_NEXT, ptr + 4, 4);
		memcpy(page_zip->data + FIL_PAGE_TYPE, ptr + 8, size);
		memset(page_zip->data + FIL_PAGE_TYPE + size, 0,
3707
		       page_zip_get_size(page_zip) - trailer_size
3708
		       - (FIL_PAGE_TYPE + size));
3709 3710
		memcpy(page_zip->data + page_zip_get_size(page_zip)
		       - trailer_size, ptr + 8 + size, trailer_size);
3711

3712 3713 3714 3715 3716 3717
		if (UNIV_UNLIKELY(!page_zip_decompress(page_zip, page))) {

			goto corrupt;
		}
	}

3718
	return(ptr + 8 + size + trailer_size);
3719
}
3720 3721 3722 3723 3724 3725 3726 3727 3728 3729 3730 3731 3732

/**************************************************************************
Calculate the compressed page checksum. */

ulint
page_zip_calc_checksum(
/*===================*/
				/* out: page checksum */
	const void*	data,	/* in: compressed page */
	ulint		size)	/* in: size of compressed page */
{
	/* Exclude the 32-bit checksum field from the checksum. */
	return((ulint) adler32(0,
3733 3734
			       ((const Bytef*) data) + FIL_PAGE_OFFSET,
			       size - FIL_PAGE_OFFSET));
3735
}