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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-04 18:00:34 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-04 18:00:34 +0000
commit3f619478f796eddbba6e39502fe941b285dd97b1 (patch)
treee2c7b5777f728320e5b5542b6213fd3591ba51e2 /storage/myisam/mi_rnext.c
parentInitial commit. (diff)
downloadmariadb-3f619478f796eddbba6e39502fe941b285dd97b1.tar.xz
mariadb-3f619478f796eddbba6e39502fe941b285dd97b1.zip
Adding upstream version 1:10.11.6.upstream/1%10.11.6upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'storage/myisam/mi_rnext.c')
-rw-r--r--storage/myisam/mi_rnext.c155
1 files changed, 155 insertions, 0 deletions
diff --git a/storage/myisam/mi_rnext.c b/storage/myisam/mi_rnext.c
new file mode 100644
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--- /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 */