branches/zip: Fix some bugs

btr_page_split_and_insert(): Avoid dereferencing pointers to garbage on
the old page.

btr_cur_pessimistic_insert(): Pass pointer to big_rec_vec to
btr_cur_optimistic_insert().

trx_undo_prev_version_build(): Only invoke rec_set_field_extern_bits()
if n_ext_vect > 0.

row_ins_index_entry_low(): Simplify a debug assertion.

page_copy_rec_list_end_no_locks(): Make the loop slightly more readable.

page_delete_rec_list_end(): Delete records on compressed pages one by one.

btr/btr0btr.c

@@ -1668,6 +1668,7 @@ btr_page_split_and_insert(
 	byte*		buf = 0; /* remove warning */
 	rec_t*		move_limit;
 	ibool		insert_will_fit;
+	ibool		insert_left;
 	ulint		n_iterations = 0;
 	rec_t*		rec;
 	mem_heap_t*	heap;
@@ -1727,9 +1728,8 @@ func_start:
 	first record (move_limit) on original page which ends up on the
 	upper half */
 
-	if (split_rec != NULL) {
-		first_rec = split_rec;
-		move_limit = split_rec;
+	if (split_rec) {
+		first_rec = move_limit = split_rec;
 	} else {
 		buf = mem_alloc(rec_get_converted_size(cursor->index, tuple));
 
@@ -1752,10 +1752,12 @@ func_start:
 		offsets = rec_get_offsets(split_rec, cursor->index, offsets,
 							n_uniq, &heap);
 
+		insert_left = cmp_dtuple_rec(tuple, split_rec, offsets) < 0;
 		insert_will_fit = btr_page_insert_fits(cursor,
 					split_rec, offsets, tuple, heap);
 	} else {
 		mem_free(buf);
+		insert_left = FALSE;
 		insert_will_fit = btr_page_insert_fits(cursor,
 					NULL, NULL, tuple, heap);
 	}
@@ -1799,22 +1801,16 @@ func_start:
 		lock_update_split_right(right_page, left_page);
 	}
 
+	/* At this point, split_rec, move_limit and first_rec may point
+	to garbage on the old page. */
+
 	/* 6. The split and the tree modification is now completed. Decide the
 	page where the tuple should be inserted */
 
-	if (split_rec == NULL) {
-		insert_page = right_page;
-
+	if (insert_left) {
+		insert_page = left_page;
 	} else {
-		offsets = rec_get_offsets(first_rec, cursor->index,
-						offsets, n_uniq, &heap);
-
-		if (cmp_dtuple_rec(tuple, first_rec, offsets) >= 0) {
-
 		insert_page = right_page;
-		} else {
-			insert_page = left_page;
-		}
 	}
 
 	insert_page_zip = buf_block_get_page_zip(buf_block_align(insert_page));

btr/btr0cur.c

@@ -1230,8 +1230,8 @@ btr_cur_pessimistic_insert(
 
 	cursor->flag = BTR_CUR_BINARY;
 
-	err = btr_cur_optimistic_insert(flags, cursor, entry, rec, big_rec,
-							ext, n_ext, thr, mtr);
+	err = btr_cur_optimistic_insert(flags, cursor, entry, rec,
+					&big_rec_vec, ext, n_ext, thr, mtr);
 	if (err != DB_FAIL) {
 
 		return(err);

page/page0page.c

@@ -504,7 +504,6 @@ page_copy_rec_list_end_no_locks(
 {
 	page_cur_t	cur1;
 	page_cur_t	cur2;
-	rec_t*		sup;
 	mem_heap_t*	heap		= NULL;
 	ulint		offsets_[REC_OFFS_NORMAL_SIZE];
 	ulint*		offsets		= offsets_;
@@ -528,13 +527,8 @@ page_copy_rec_list_end_no_locks(
 
 	/* Copy records from the original page to the new page */
 
-	sup = page_get_supremum_rec(ut_align_down(rec, UNIV_PAGE_SIZE));
-
-	for (;;) {
+	while (!page_cur_is_after_last(&cur1)) {
 		rec_t*	cur1_rec = page_cur_get_rec(&cur1);
-		if (cur1_rec == sup) {
-			break;
-		}
 		offsets = rec_get_offsets(cur1_rec, index, offsets,
 					ULINT_UNDEFINED, &heap);
 		if (UNIV_UNLIKELY(!page_cur_rec_insert(&cur2, NULL,
@@ -573,7 +567,9 @@ The records are copied to the start of the record list on new_page. */
 ibool
 page_copy_rec_list_end(
 /*===================*/
-					/* out: TRUE on success */
+					/* out: TRUE on success; FALSE on
+					compression failure (new_page will
+					be decompressed from new_page_zip) */
 	page_t*		new_page,	/* in/out: index page to copy to */
 	page_zip_des_t*	new_page_zip,	/* in/out: compressed page, or NULL */
 	rec_t*		rec,		/* in: record on page */
@@ -801,12 +797,16 @@ page_delete_rec_list_end(
 	page_zip_des_t*	page_zip,/* in/out: compressed page, or NULL */
 	mtr_t*		mtr)	/* in: mtr */
 {
-	page_dir_slot_t* slot;
+	page_dir_slot_t*slot;
 	ulint		slot_index;
 	rec_t*		last_rec;
 	rec_t*		prev_rec;
 	ulint		n_owned;
 	page_t*		page;
+	mem_heap_t*	heap		= NULL;
+	ulint		offsets_[REC_OFFS_NORMAL_SIZE];
+	ulint*		offsets		= offsets_;
+	*offsets_ = (sizeof offsets_) / sizeof *offsets_;
 
 	ut_ad(size == ULINT_UNDEFINED || size < UNIV_PAGE_SIZE);
 	ut_ad(!page_zip || page_rec_is_comp(rec));
@@ -835,16 +835,42 @@ page_delete_rec_list_end(
 			? MLOG_COMP_LIST_END_DELETE
 			: MLOG_LIST_END_DELETE, mtr);
 
+	if (UNIV_LIKELY_NULL(page_zip)) {
+		ulint		log_mode;
+
+		ut_a(page_is_comp(page));
+		/* Individual deletes are not logged */
+
+		log_mode = mtr_set_log_mode(mtr, MTR_LOG_NONE);
+
+		do {
+			page_cur_t	cur;
+			page_cur_position(rec, &cur);
+
+			offsets = rec_get_offsets(rec, index, offsets,
+					ULINT_UNDEFINED, &heap);
+			rec = rec_get_next_ptr(rec, TRUE);
+			page_cur_delete_rec(&cur, index, offsets,
+					page_zip, mtr);
+		} while (ut_align_offset(rec, UNIV_PAGE_SIZE)
+			!= PAGE_NEW_SUPREMUM);
+
+		if (UNIV_LIKELY_NULL(heap)) {
+			mem_heap_free(heap);
+		}
+
+		/* Restore log mode */
+
+		mtr_set_log_mode(mtr, log_mode);
+		return;
+	}
+
 	prev_rec = page_rec_get_prev(rec);
 
 	last_rec = page_rec_get_prev(page_get_supremum_rec(page));
 
 	if ((size == ULINT_UNDEFINED) || (n_recs == ULINT_UNDEFINED)) {
 		rec_t*		rec2		= rec;
-		mem_heap_t*	heap		= NULL;
-		ulint		offsets_[REC_OFFS_NORMAL_SIZE];
-		ulint*		offsets		= offsets_;
-		*offsets_ = (sizeof offsets_) / sizeof *offsets_;
 		/* Calculate the sum of sizes and the number of records */
 		size = 0;
 		n_recs = 0;
@@ -889,27 +915,6 @@ page_delete_rec_list_end(
 		n_owned = rec_get_n_owned_new(rec2) - count;
 		slot_index = page_dir_find_owner_slot(rec2);
 		slot = page_dir_get_nth_slot(page, slot_index);
-
-		if (UNIV_LIKELY_NULL(page_zip)) {
-			ulint	n_slots;
-			rec2 = rec;
-			do {
-				/* The compression algorithm expects
-				info_bits and n_owned to be 0
-				for deleted records. */
-				rec2[-REC_N_NEW_EXTRA_BYTES] = 0;
-				rec2 = rec_get_next_ptr(rec2, TRUE);
-			} while (rec2);
-
-			/* The compression algorithm expects the removed
-			slots in the page directory to be cleared. */
-
-			n_slots = page_dir_get_n_slots(page) - slot_index - 1;
-			ut_ad(n_slots < UNIV_PAGE_SIZE / PAGE_DIR_SLOT_SIZE);
-
-			memset(slot - (n_slots * PAGE_DIR_SLOT_SIZE), 0,
-				n_slots * PAGE_DIR_SLOT_SIZE);
-		}
 	} else {
 		rec_t*	rec2	= rec;
 		ulint	count	= 0;
@@ -928,9 +933,9 @@ page_delete_rec_list_end(
 	}
 
 	page_dir_slot_set_rec(slot, page_get_supremum_rec(page));
-	page_dir_slot_set_n_owned(slot, page_zip, n_owned);
+	page_dir_slot_set_n_owned(slot, NULL, n_owned);
 
-	page_dir_set_n_slots(page, page_zip, slot_index + 1);
+	page_dir_set_n_slots(page, NULL, slot_index + 1);
 
 	/* Remove the record chain segment from the record chain */
 	page_rec_set_next(prev_rec, page_get_supremum_rec(page));
@@ -938,16 +943,13 @@ page_delete_rec_list_end(
 	/* Catenate the deleted chain segment to the page free list */
 
 	page_rec_set_next(last_rec, page_header_get_ptr(page, PAGE_FREE));
-	page_header_set_ptr(page, page_zip, PAGE_FREE, rec);
+	page_header_set_ptr(page, NULL, PAGE_FREE, rec);
 
-	page_header_set_field(page, page_zip, PAGE_GARBAGE,
+	page_header_set_field(page, NULL, PAGE_GARBAGE,
 			size + page_header_get_field(page, PAGE_GARBAGE));
 
-	page_header_set_field(page, page_zip, PAGE_N_RECS,
+	page_header_set_field(page, NULL, PAGE_N_RECS,
 				(ulint)(page_get_n_recs(page) - n_recs));
-	if (UNIV_LIKELY_NULL(page_zip)) {
-		page_zip_dir_rewrite(page_zip, page);
-	}
 }
 
 /*****************************************************************

row/row0ins.c

@@ -2021,11 +2021,10 @@ row_ins_index_entry_low(
 		rec_t*	first_rec = page_rec_get_next(
 				page_get_infimum_rec(page));
 
-		if (UNIV_LIKELY(first_rec != page_get_supremum_rec(page))) {
-			ut_a(rec_get_n_fields(first_rec, index)
+		ut_ad(page_rec_is_supremum(first_rec)
+			|| rec_get_n_fields(first_rec, index)
 			== dtuple_get_n_fields(entry));
 	}
-	}
 #endif
 
 	n_unique = dict_index_get_n_unique(index);

trx/trx0rec.c

@@ -1406,8 +1406,10 @@ trx_undo_prev_version_build(
 		*old_vers = rec_convert_dtuple_to_rec(buf, index, entry);
 
 		/* Now set the extern bits in the old version of the record */
+		if (n_ext_vect) {
 			rec_set_field_extern_bits(*old_vers, index, NULL,
 						ext_vect, n_ext_vect);
+		}
 		mem_free(ext_vect);
 	} else {
 		buf = mem_heap_alloc(heap, rec_offs_size(offsets));