diff options
Diffstat (limited to 'storage/heap/hp_delete.c')
| -rw-r--r-- | storage/heap/hp_delete.c | 202 |
1 files changed, 202 insertions, 0 deletions
diff --git a/storage/heap/hp_delete.c b/storage/heap/hp_delete.c new file mode 100644 index 00000000000..5287533ae0a --- /dev/null +++ b/storage/heap/hp_delete.c @@ -0,0 +1,202 @@ +/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB + + 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; either version 2 of the License, or + (at your option) any later version. + + 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ + +/* remove current record in heap-database */ + +#include "heapdef.h" + +int heap_delete(HP_INFO *info, const byte *record) +{ + byte *pos; + HP_SHARE *share=info->s; + HP_KEYDEF *keydef, *end, *p_lastinx; + DBUG_ENTER("heap_delete"); + DBUG_PRINT("enter",("info: %lx record: 0x%lx",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; + *((byte**) pos)=share->del_link; + share->del_link=pos; + pos[share->reclength]=0; /* Record deleted */ + share->deleted++; + info->current_hash_ptr=0; +#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 byte *record, byte *recpos, int flag) +{ + heap_rb_param custom_arg; + uint 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); + info->s->index_length+= (keyinfo->rb_tree.allocated-old_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 byte *record, byte *recpos, int flag) +{ + ulong blength,pos2,pos_hashnr,lastpos_hashnr; + 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 */ + pos= hp_find_hash(&keyinfo->block, + hp_mask(hp_rec_hashnr(keyinfo, record), blength, + share->records + 1)); + gpos = pos3 = 0; + + while (pos->ptr_to_rec != recpos) + { + if (flag && !hp_rec_key_cmp(keyinfo, record, pos->ptr_to_rec, 0)) + 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: 0x%lx", + 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; + } + else + keyinfo->hash_buckets--; + + if (empty == lastpos) /* deleted last hash key */ + DBUG_RETURN (0); + + /* Move the last key (lastpos) */ + lastpos_hashnr = hp_rec_hashnr(keyinfo, lastpos->ptr_to_rec); + /* 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 = hp_rec_hashnr(keyinfo, pos->ptr_to_rec); + /* 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)) + { /* Identical key-positions */ + if (pos2 != share->records) + { + empty[0]=lastpos[0]; + hp_movelink(lastpos, pos, empty); + DBUG_RETURN(0); + } + pos3= pos; /* Link pos->next after lastpos */ + } + else + { + 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); +} |