1/***************************************************************************** 2 3Copyright (c) 1994, 2019, Oracle and/or its affiliates. All Rights Reserved. 4 5This program is free software; you can redistribute it and/or modify it under 6the terms of the GNU General Public License, version 2.0, as published by the 7Free Software Foundation. 8 9This program is also distributed with certain software (including but not 10limited to OpenSSL) that is licensed under separate terms, as designated in a 11particular file or component or in included license documentation. The authors 12of MySQL hereby grant you an additional permission to link the program and 13your derivative works with the separately licensed software that they have 14included with MySQL. 15 16This program is distributed in the hope that it will be useful, but WITHOUT 17ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS 18FOR A PARTICULAR PURPOSE. See the GNU General Public License, version 2.0, 19for more details. 20 21You should have received a copy of the GNU General Public License along with 22this program; if not, write to the Free Software Foundation, Inc., 2351 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 24 25*****************************************************************************/ 26 27/** @file include/page0cur.ic 28 The page cursor 29 30 Created 10/4/1994 Heikki Tuuri 31 *************************************************************************/ 32 33#include "buf0types.h" 34#include "page0page.h" 35 36#ifdef UNIV_DEBUG 37#ifndef UNIV_HOTBACKUP 38#include "rem0cmp.h" 39#endif /* !UNIV_HOTBACKUP */ 40 41/** Gets pointer to the page frame where the cursor is positioned. 42 @return page */ 43UNIV_INLINE 44page_t *page_cur_get_page(page_cur_t *cur) /*!< in: page cursor */ 45{ 46 ut_ad(cur); 47 ut_ad(page_align(cur->rec) == cur->block->frame); 48 49 return (page_align(cur->rec)); 50} 51 52/** Gets pointer to the buffer block where the cursor is positioned. 53 @return page */ 54UNIV_INLINE 55buf_block_t *page_cur_get_block(page_cur_t *cur) /*!< in: page cursor */ 56{ 57 ut_ad(cur); 58 ut_ad(page_align(cur->rec) == cur->block->frame); 59 return (cur->block); 60} 61 62/** Gets pointer to the page frame where the cursor is positioned. 63 @return page */ 64UNIV_INLINE 65page_zip_des_t *page_cur_get_page_zip(page_cur_t *cur) /*!< in: page cursor */ 66{ 67 return (buf_block_get_page_zip(page_cur_get_block(cur))); 68} 69 70/** Gets the record where the cursor is positioned. 71 @return record */ 72UNIV_INLINE 73rec_t *page_cur_get_rec(page_cur_t *cur) /*!< in: page cursor */ 74{ 75 ut_ad(cur); 76 ut_ad(page_align(cur->rec) == cur->block->frame); 77 78 return (cur->rec); 79} 80#endif /* UNIV_DEBUG */ 81 82/** Sets the cursor object to point before the first user record 83 on the page. */ 84UNIV_INLINE 85void page_cur_set_before_first(const buf_block_t *block, /*!< in: index page */ 86 page_cur_t *cur) /*!< in: cursor */ 87{ 88 cur->block = (buf_block_t *)block; 89 cur->rec = page_get_infimum_rec(buf_block_get_frame(cur->block)); 90} 91 92/** Sets the cursor object to point after the last user record on 93 the page. */ 94UNIV_INLINE 95void page_cur_set_after_last(const buf_block_t *block, /*!< in: index page */ 96 page_cur_t *cur) /*!< in: cursor */ 97{ 98 cur->block = (buf_block_t *)block; 99 cur->rec = page_get_supremum_rec(buf_block_get_frame(cur->block)); 100} 101 102/** Returns TRUE if the cursor is before first user record on page. 103 @return true if at start */ 104UNIV_INLINE 105ibool page_cur_is_before_first(const page_cur_t *cur) /*!< in: cursor */ 106{ 107 ut_ad(cur); 108 ut_ad(page_align(cur->rec) == cur->block->frame); 109 return (page_rec_is_infimum(cur->rec)); 110} 111 112/** Returns TRUE if the cursor is after last user record. 113 @return true if at end */ 114UNIV_INLINE 115ibool page_cur_is_after_last(const page_cur_t *cur) /*!< in: cursor */ 116{ 117 ut_ad(cur); 118 ut_ad(page_align(cur->rec) == cur->block->frame); 119 return (page_rec_is_supremum(cur->rec)); 120} 121 122/** Positions the cursor on the given record. */ 123UNIV_INLINE 124void page_cur_position(const rec_t *rec, /*!< in: record on a page */ 125 const buf_block_t *block, /*!< in: buffer block 126 containing the record */ 127 page_cur_t *cur) /*!< out: page cursor */ 128{ 129 ut_ad(rec && block && cur); 130 ut_ad(page_align(rec) == block->frame); 131 132 cur->rec = (rec_t *)rec; 133 cur->block = (buf_block_t *)block; 134} 135 136/** Moves the cursor to the next record on page. */ 137UNIV_INLINE 138void page_cur_move_to_next( 139 page_cur_t *cur) /*!< in/out: cursor; must not be after last */ 140{ 141 ut_ad(!page_cur_is_after_last(cur)); 142 143 cur->rec = page_rec_get_next(cur->rec); 144} 145 146/** Moves the cursor to the previous record on page. */ 147UNIV_INLINE 148void page_cur_move_to_prev( 149 page_cur_t *cur) /*!< in/out: page cursor, not before first */ 150{ 151 ut_ad(!page_cur_is_before_first(cur)); 152 153 cur->rec = page_rec_get_prev(cur->rec); 154} 155 156#ifndef UNIV_HOTBACKUP 157/** Search the right position for a page cursor. 158@param[in] block buffer block 159@param[in] index index tree 160@param[in] tuple data tuple 161@param[in] mode PAGE_CUR_L, PAGE_CUR_LE, PAGE_CUR_G, or PAGE_CUR_GE 162@param[out] cursor page cursor 163@return number of matched fields on the left */ 164UNIV_INLINE 165ulint page_cur_search(const buf_block_t *block, const dict_index_t *index, 166 const dtuple_t *tuple, page_cur_mode_t mode, 167 page_cur_t *cursor) { 168 ulint low_match = 0; 169 ulint up_match = 0; 170 171 ut_ad(dtuple_check_typed(tuple)); 172 173 page_cur_search_with_match(block, index, tuple, mode, &up_match, &low_match, 174 cursor, nullptr); 175 return (low_match); 176} 177 178/** Search the right position for a page cursor. 179@param[in] block buffer block 180@param[in] index index tree 181@param[in] tuple data tuple 182@param[out] cursor page cursor 183@return number of matched fields on the left */ 184UNIV_INLINE 185ulint page_cur_search(const buf_block_t *block, const dict_index_t *index, 186 const dtuple_t *tuple, page_cur_t *cursor) { 187 return (page_cur_search(block, index, tuple, PAGE_CUR_LE, cursor)); 188} 189 190/** Inserts a record next to page cursor. Returns pointer to inserted record if 191 succeed, i.e., enough space available, NULL otherwise. The cursor stays at 192 the same logical position, but the physical position may change if it is 193 pointing to a compressed page that was reorganized. 194 195 IMPORTANT: The caller will have to update IBUF_BITMAP_FREE 196 if this is a compressed leaf page in a secondary index. 197 This has to be done either within the same mini-transaction, 198 or by invoking ibuf_reset_free_bits() before mtr_commit(). 199 200 @return pointer to record if succeed, NULL otherwise */ 201UNIV_INLINE 202rec_t *page_cur_tuple_insert( 203 page_cur_t *cursor, /*!< in/out: a page cursor */ 204 const dtuple_t *tuple, /*!< in: pointer to a data tuple */ 205 dict_index_t *index, /*!< in: record descriptor */ 206 ulint **offsets, /*!< out: offsets on *rec */ 207 mem_heap_t **heap, /*!< in/out: pointer to memory heap, or NULL */ 208 mtr_t *mtr, /*!< in: mini-transaction handle, or NULL */ 209 bool use_cache) 210/*!< in: if true, then use record cache to 211hold the tuple converted record. */ 212{ 213 rec_t *rec; 214 rec_t *insert_rec; 215 216 ulint size = rec_get_converted_size(index, tuple); 217 218 if (!*heap) { 219 *heap = mem_heap_create( 220 size + (4 + REC_OFFS_HEADER_SIZE + dtuple_get_n_fields(tuple)) * 221 sizeof **offsets); 222 } 223 224 rec = rec_convert_dtuple_to_rec((byte *)mem_heap_alloc(*heap, size), index, 225 tuple); 226 227 *offsets = rec_get_offsets(rec, index, *offsets, ULINT_UNDEFINED, heap); 228 229 ut_ad(cmp_dtuple_rec(tuple, rec, index, *offsets) == 0); 230 231 if (buf_block_get_page_zip(cursor->block)) { 232 insert_rec = page_cur_insert_rec_zip(cursor, index, rec, *offsets, mtr); 233 } else { 234 insert_rec = 235 page_cur_insert_rec_low(cursor->rec, index, rec, *offsets, mtr); 236 } 237 238#ifdef UNIV_DEBUG 239 if (insert_rec != nullptr) { 240 if (cmp_dtuple_rec(tuple, insert_rec, index, *offsets) != 0) { 241 std::cerr << "tuple=" << rec_printer(tuple).str() << std::endl; 242 std::cerr << "rec=" << rec_printer(insert_rec, *offsets).str() 243 << std::endl; 244 } 245 } 246 ut_ad(!insert_rec || !cmp_dtuple_rec(tuple, insert_rec, index, *offsets)); 247#endif /* UNIV_DEBUG */ 248 249 return (insert_rec); 250} 251 252/** Insert a record next to page cursor. Record is directly copied to 253the page from tuple without creating intermediate copy of the record. 254 255@param[in,out] cursor a page cursor 256@param[in] tuple pointer to a data tuple 257@param[in] index record descriptor 258@param[in] mtr mini-transaction handle, or NULL 259 260@return pointer to record if succeed, NULL otherwise */ 261UNIV_INLINE 262rec_t *page_cur_tuple_direct_insert(page_cur_t *cursor, const dtuple_t *tuple, 263 dict_index_t *index, mtr_t *mtr) { 264 rec_t *rec; 265 266 ut_ad(index->table->is_intrinsic()); 267 268 rec = page_cur_direct_insert_rec_low(cursor->rec, index, tuple, mtr); 269 270 return (rec); 271} 272#endif /* !UNIV_HOTBACKUP */ 273 274/** Inserts a record next to page cursor. Returns pointer to inserted record if 275 succeed, i.e., enough space available, NULL otherwise. The cursor stays at 276 the same logical position, but the physical position may change if it is 277 pointing to a compressed page that was reorganized. 278 279 IMPORTANT: The caller will have to update IBUF_BITMAP_FREE 280 if this is a compressed leaf page in a secondary index. 281 This has to be done either within the same mini-transaction, 282 or by invoking ibuf_reset_free_bits() before mtr_commit(). 283 284 @return pointer to record if succeed, NULL otherwise */ 285UNIV_INLINE 286rec_t *page_cur_rec_insert( 287 page_cur_t *cursor, /*!< in/out: a page cursor */ 288 const rec_t *rec, /*!< in: record to insert */ 289 dict_index_t *index, /*!< in: record descriptor */ 290 ulint *offsets, /*!< in/out: rec_get_offsets(rec, index) */ 291 mtr_t *mtr) /*!< in: mini-transaction handle, or NULL */ 292{ 293 if (buf_block_get_page_zip(cursor->block)) { 294 return (page_cur_insert_rec_zip(cursor, index, rec, offsets, mtr)); 295 } else { 296 return (page_cur_insert_rec_low(cursor->rec, index, rec, offsets, mtr)); 297 } 298} 299