From a175314c3e5827eb193872241446f2f8f5c9d33c Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 4 May 2024 20:07:14 +0200 Subject: Adding upstream version 1:10.5.12. Signed-off-by: Daniel Baumann --- storage/myisam/mi_rnext.c | 155 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 155 insertions(+) create mode 100644 storage/myisam/mi_rnext.c (limited to 'storage/myisam/mi_rnext.c') diff --git a/storage/myisam/mi_rnext.c b/storage/myisam/mi_rnext.c new file mode 100644 index 00000000..7124c102 --- /dev/null +++ b/storage/myisam/mi_rnext.c @@ -0,0 +1,155 @@ +/* + Copyright (c) 2000, 2010, Oracle and/or its affiliates + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; version 2 of the License. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335 USA */ + +#include "myisamdef.h" +#include "rt_index.h" + + /* + Read next row with the same key as previous read + One may have done a write, update or delete of the previous row. + NOTE! Even if one changes the previous row, the next read is done + based on the position of the last used key! + */ + +int mi_rnext(MI_INFO *info, uchar *buf, int inx) +{ + int error,changed; + uint flag; + check_result_t check= CHECK_POS; + uint update_mask= HA_STATE_NEXT_FOUND; + DBUG_ENTER("mi_rnext"); + + if ((inx = _mi_check_index(info,inx)) < 0) + DBUG_RETURN(my_errno); + flag=SEARCH_BIGGER; /* Read next */ + if (info->lastpos == HA_OFFSET_ERROR && info->update & HA_STATE_PREV_FOUND) + flag=0; /* Read first */ + + if (fast_mi_readinfo(info)) + DBUG_RETURN(my_errno); + if (info->s->concurrent_insert) + mysql_rwlock_rdlock(&info->s->key_root_lock[inx]); + changed=_mi_test_if_changed(info); + if (!flag) + { + switch(info->s->keyinfo[inx].key_alg){ +#ifdef HAVE_RTREE_KEYS + case HA_KEY_ALG_RTREE: + error=rtree_get_first(info,inx,info->lastkey_length); + break; +#endif + case HA_KEY_ALG_BTREE: + default: + error=_mi_search_first(info,info->s->keyinfo+inx, + info->s->state.key_root[inx]); + break; + } + /* + "search first" failed. This means we have no pivot for + "search next", or in other words MI_INFO::lastkey is + likely uninitialized. + + Normally SQL layer would never request "search next" if + "search first" failed. But HANDLER may do anything. + + As mi_rnext() without preceding mi_rkey()/mi_rfirst() + equals to mi_rfirst(), we must restore original state + as if failing mi_rfirst() was not called. + */ + if (error) + update_mask|= HA_STATE_PREV_FOUND; + } + else + { + switch (info->s->keyinfo[inx].key_alg) { +#ifdef HAVE_RTREE_KEYS + case HA_KEY_ALG_RTREE: + /* + Note that rtree doesn't support that the table + may be changed since last call, so we do need + to skip rows inserted by other threads like in btree + */ + error= rtree_get_next(info,inx,info->lastkey_length); + break; +#endif + case HA_KEY_ALG_BTREE: + default: + if (!changed) + error= _mi_search_next(info,info->s->keyinfo+inx,info->lastkey, + info->lastkey_length,flag, + info->s->state.key_root[inx]); + else + error= _mi_search(info,info->s->keyinfo+inx,info->lastkey, + USE_WHOLE_KEY,flag, info->s->state.key_root[inx]); + } + } + + if (!error) + { + while ((info->s->concurrent_insert && + info->lastpos >= info->state->data_file_length) || + (check= mi_check_index_tuple(info, inx, buf)) == CHECK_NEG) + { + /* + If we are at the last key on the key page, allow writers to + access the index. + */ + if (info->int_keypos >= info->int_maxpos && + mi_yield_and_check_if_killed(info, inx)) + { + error= 1; + break; + } + + /* + Skip rows that are either inserted by other threads since + we got a lock or do not match pushed index conditions + */ + if ((error=_mi_search_next(info,info->s->keyinfo+inx, + info->lastkey, + info->lastkey_length, + SEARCH_BIGGER, + info->s->state.key_root[inx]))) + break; + } + } + + if (info->s->concurrent_insert) + mysql_rwlock_unlock(&info->s->key_root_lock[inx]); + + /* Don't clear if database-changed */ + info->update&= (HA_STATE_CHANGED | HA_STATE_ROW_CHANGED); + info->update|= update_mask; + + if (error || check != CHECK_POS) + { + fast_mi_writeinfo(info); + if (my_errno == HA_ERR_KEY_NOT_FOUND) + my_errno=HA_ERR_END_OF_FILE; + } + else if (!buf) + { + fast_mi_writeinfo(info); + DBUG_RETURN(info->lastpos==HA_OFFSET_ERROR ? my_errno : 0); + } + else if (!(*info->read_record)(info,info->lastpos,buf)) + { + info->update|= HA_STATE_AKTIV; /* Record is read */ + DBUG_RETURN(0); + } + DBUG_PRINT("error",("Got error: %d, errno: %d",error, my_errno)); + DBUG_RETURN(my_errno); +} /* mi_rnext */ -- cgit v1.2.3