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-rw-r--r--storage/heap/hp_delete.c232
1 files changed, 232 insertions, 0 deletions
diff --git a/storage/heap/hp_delete.c b/storage/heap/hp_delete.c
new file mode 100644
index 00000000..9579fb51
--- /dev/null
+++ b/storage/heap/hp_delete.c
@@ -0,0 +1,232 @@
+/* Copyright (c) 2000, 2012, Oracle and/or its affiliates. All rights reserved.
+
+ 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 Street, Fifth Floor, Boston, MA 02110-1335 USA */
+
+/* remove current record in heap-database */
+
+#include "heapdef.h"
+
+int heap_delete(HP_INFO *info, const uchar *record)
+{
+ uchar *pos;
+ HP_SHARE *share=info->s;
+ HP_KEYDEF *keydef, *end, *p_lastinx;
+ DBUG_ENTER("heap_delete");
+ DBUG_PRINT("enter",("info: %p record: %p", info, record));
+
+ test_active(info);
+
+ if (info->opt_flag & READ_CHECK_USED && hp_rectest(info,record))
+ DBUG_RETURN(my_errno); /* Record changed */
+ share->changed=1;
+
+ if ( --(share->records) < share->blength >> 1) share->blength>>=1;
+ pos=info->current_ptr;
+
+ p_lastinx = share->keydef + info->lastinx;
+ for (keydef = share->keydef, end = keydef + share->keys; keydef < end;
+ keydef++)
+ {
+ if ((*keydef->delete_key)(info, keydef, record, pos, keydef == p_lastinx))
+ goto err;
+ }
+
+ info->update=HA_STATE_DELETED;
+ *((uchar**) pos)=share->del_link;
+ share->del_link=pos;
+ pos[share->visible]=0; /* Record deleted */
+ share->deleted++;
+ share->key_version++;
+#if !defined(DBUG_OFF) && defined(EXTRA_HEAP_DEBUG)
+ DBUG_EXECUTE("check_heap",heap_check_heap(info, 0););
+#endif
+
+ DBUG_RETURN(0);
+err:
+ if (++(share->records) == share->blength)
+ share->blength+= share->blength;
+ DBUG_RETURN(my_errno);
+}
+
+
+/*
+ Remove one key from rb-tree
+*/
+
+int hp_rb_delete_key(HP_INFO *info, register HP_KEYDEF *keyinfo,
+ const uchar *record, uchar *recpos, int flag)
+{
+ heap_rb_param custom_arg;
+ size_t old_allocated;
+ int res;
+
+ if (flag)
+ info->last_pos= NULL; /* For heap_rnext/heap_rprev */
+
+ custom_arg.keyseg= keyinfo->seg;
+ custom_arg.key_length= hp_rb_make_key(keyinfo, info->recbuf, record, recpos);
+ custom_arg.search_flag= SEARCH_SAME;
+ old_allocated= keyinfo->rb_tree.allocated;
+ res= tree_delete(&keyinfo->rb_tree, info->recbuf, custom_arg.key_length,
+ &custom_arg);
+ info->s->index_length-= (old_allocated - keyinfo->rb_tree.allocated);
+ return res;
+}
+
+
+/*
+ Remove one key from hash-table
+
+ SYNPOSIS
+ hp_delete_key()
+ info Hash handler
+ keyinfo key definition of key that we want to delete
+ record row data to be deleted
+ recpos Pointer to heap record in memory
+ flag Is set if we want's to correct info->current_ptr
+
+ RETURN
+ 0 Ok
+ other Error code
+*/
+
+int hp_delete_key(HP_INFO *info, register HP_KEYDEF *keyinfo,
+ const uchar *record, uchar *recpos, int flag)
+{
+ ulong blength, pos2, pos_hashnr, lastpos_hashnr, key_pos;
+ HASH_INFO *lastpos,*gpos,*pos,*pos3,*empty,*last_ptr;
+ HP_SHARE *share=info->s;
+ DBUG_ENTER("hp_delete_key");
+
+ blength=share->blength;
+ if (share->records+1 == blength)
+ blength+= blength;
+ lastpos=hp_find_hash(&keyinfo->block,share->records);
+ last_ptr=0;
+
+ /* Search after record with key */
+ key_pos= hp_mask(hp_rec_hashnr(keyinfo, record), blength, share->records + 1);
+ pos= hp_find_hash(&keyinfo->block, key_pos);
+
+ gpos = pos3 = 0;
+
+ while (pos->ptr_to_rec != recpos)
+ {
+ if (flag && !hp_rec_key_cmp(keyinfo, record, pos->ptr_to_rec))
+ last_ptr=pos; /* Previous same key */
+ gpos=pos;
+ if (!(pos=pos->next_key))
+ {
+ DBUG_RETURN(my_errno=HA_ERR_CRASHED); /* This shouldn't happend */
+ }
+ }
+
+ /* Remove link to record */
+
+ if (flag)
+ {
+ /* Save for heap_rnext/heap_rprev */
+ info->current_hash_ptr=last_ptr;
+ info->current_ptr = last_ptr ? last_ptr->ptr_to_rec : 0;
+ DBUG_PRINT("info",("Corrected current_ptr to point at: %p",
+ info->current_ptr));
+ }
+ empty=pos;
+ if (gpos)
+ gpos->next_key=pos->next_key; /* unlink current ptr */
+ else if (pos->next_key)
+ {
+ empty=pos->next_key;
+ pos->ptr_to_rec= empty->ptr_to_rec;
+ pos->next_key= empty->next_key;
+ pos->hash_of_key= empty->hash_of_key;
+ }
+ else
+ keyinfo->hash_buckets--;
+
+ if (empty == lastpos) /* deleted last hash key */
+ DBUG_RETURN (0);
+
+ /* Move the last key (lastpos) */
+ lastpos_hashnr= lastpos->hash_of_key;
+ /* pos is where lastpos should be */
+ pos=hp_find_hash(&keyinfo->block, hp_mask(lastpos_hashnr, share->blength,
+ share->records));
+ if (pos == empty) /* Move to empty position. */
+ {
+ empty[0]=lastpos[0];
+ DBUG_RETURN(0);
+ }
+ pos_hashnr= pos->hash_of_key;
+ /* pos3 is where the pos should be */
+ pos3= hp_find_hash(&keyinfo->block,
+ hp_mask(pos_hashnr, share->blength, share->records));
+ if (pos != pos3)
+ { /* pos is on wrong posit */
+ empty[0]=pos[0]; /* Save it here */
+ pos[0]=lastpos[0]; /* This shold be here */
+ hp_movelink(pos, pos3, empty); /* Fix link to pos */
+ DBUG_RETURN(0);
+ }
+ pos2= hp_mask(lastpos_hashnr, blength, share->records + 1);
+ if (pos2 == hp_mask(pos_hashnr, blength, share->records + 1))
+ {
+ /* lastpos and the row in the main bucket entry (pos) has the same hash */
+ if (pos2 != share->records)
+ {
+ /*
+ The bucket entry was not deleted. Copy lastpos over the
+ deleted entry and update previous link to point to it.
+ */
+ empty[0]= lastpos[0];
+ hp_movelink(lastpos, pos, empty);
+ if (last_ptr == lastpos)
+ {
+ /*
+ We moved the row that info->current_hash_ptr points to.
+ Update info->current_hash_ptr to point to the new position.
+ */
+ info->current_hash_ptr= empty;
+ }
+ DBUG_RETURN(0);
+ }
+ /*
+ Shrinking the hash table deleted the main bucket entry for this hash.
+ In this case the last entry was the first key in the key chain.
+ We move things around so that we keep the original key order to ensure
+ that heap_rnext() works.
+
+ - Move the row at the main bucket entry to the empty spot.
+ - Move the last entry first in the new chain.
+ - Link in the first element of the hash.
+ */
+ empty[0]= pos[0];
+ pos[0]= lastpos[0];
+ hp_movelink(pos, pos, empty);
+
+ /* Update current_hash_ptr if the entry moved */
+ if (last_ptr == lastpos)
+ info->current_hash_ptr= pos;
+ else if (last_ptr == pos)
+ info->current_hash_ptr= empty;
+ DBUG_RETURN(0);
+ }
+
+ pos3= 0; /* Different positions merge */
+ keyinfo->hash_buckets--;
+ empty[0]=lastpos[0];
+ hp_movelink(pos3, empty, pos->next_key);
+ pos->next_key=empty;
+ DBUG_RETURN(0);
+}
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