diff options
Diffstat (limited to 'myisam/mi_delete.c')
| -rw-r--r-- | myisam/mi_delete.c | 780 |
1 files changed, 780 insertions, 0 deletions
diff --git a/myisam/mi_delete.c b/myisam/mi_delete.c new file mode 100644 index 00000000000..4c5f3c79e17 --- /dev/null +++ b/myisam/mi_delete.c @@ -0,0 +1,780 @@ +/* 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 a row from a MyISAM table */ + +#include "fulltext.h" +#ifdef __WIN__ +#include <errno.h> +#endif + +static int d_search(MI_INFO *info,MI_KEYDEF *keyinfo,uchar *key, + uint key_length, my_off_t page, uchar *anc_buff); +static int del(MI_INFO *info,MI_KEYDEF *keyinfo,uchar *key,uchar *anc_buff, + my_off_t leaf_page,uchar *leaf_buff,uchar *keypos, + my_off_t next_block,uchar *ret_key); +static int underflow(MI_INFO *info,MI_KEYDEF *keyinfo,uchar *anc_buff, + my_off_t leaf_page, uchar *leaf_buff,uchar *keypos); +static uint remove_key(MI_KEYDEF *keyinfo,uint nod_flag,uchar *keypos, + uchar *lastkey,uchar *page_end, + my_off_t *next_block); + + +int mi_delete(MI_INFO *info,const byte *record) +{ + uint i; + uchar *old_key; + int save_errno; + char lastpos[8]; + + MYISAM_SHARE *share=info->s; + DBUG_ENTER("mi_delete"); + + /* Test if record is in datafile */ + + if (!(info->update & HA_STATE_AKTIV)) + { + DBUG_RETURN(my_errno=HA_ERR_KEY_NOT_FOUND); /* No database read */ + } + if (share->options & HA_OPTION_READ_ONLY_DATA) + { + DBUG_RETURN(my_errno=EACCES); + } + if (_mi_readinfo(info,F_WRLCK,1)) + DBUG_RETURN(my_errno); + if (info->s->calc_checksum) + info->checksum=(*info->s->calc_checksum)(info,record); + if ((*share->compare_record)(info,record)) + goto err; /* Error on read-check */ + + if (_mi_mark_file_changed(info)) + goto err; + + /* Remove all keys from the .ISAM file */ + + old_key=info->lastkey2; + for (i=0 ; i < share->base.keys ; i++ ) + { + if (((ulonglong) 1 << i) & info->s->state.key_map) + { + info->s->keyinfo[i].version++; + /* The following code block is for text searching by SerG */ + if (info->s->keyinfo[i].flag & HA_FULLTEXT ) + { + if (_mi_ft_del(info,i,(char*) old_key,record,info->lastpos)) + goto err; + } + else + { + uint key_length=_mi_make_key(info,i,old_key,record,info->lastpos); + if (_mi_ck_delete(info,i,old_key,key_length)) + goto err; + } + } + } + + if ((*share->delete_record)(info)) + goto err; /* Remove record from database */ + info->s->state.checksum-=info->checksum; + + info->update= HA_STATE_CHANGED+HA_STATE_DELETED+HA_STATE_ROW_CHANGED; + info->state->records--; + + mi_sizestore(lastpos,info->lastpos); + myisam_log_command(MI_LOG_DELETE,info,(byte*) lastpos,sizeof(lastpos),0); + VOID(_mi_writeinfo(info,WRITEINFO_UPDATE_KEYFILE)); + allow_break(); /* Allow SIGHUP & SIGINT */ + DBUG_RETURN(0); + +err: + save_errno=my_errno; + mi_sizestore(lastpos,info->lastpos); + myisam_log_command(MI_LOG_DELETE,info,(byte*) lastpos, sizeof(lastpos),0); + if (save_errno != HA_ERR_RECORD_CHANGED) + mi_mark_crashed(info); /* mark table crashed */ + VOID(_mi_writeinfo(info,WRITEINFO_UPDATE_KEYFILE)); + info->update|=HA_STATE_WRITTEN; /* Buffer changed */ + allow_break(); /* Allow SIGHUP & SIGINT */ + my_errno=save_errno; + if (save_errno == HA_ERR_KEY_NOT_FOUND) + my_errno=HA_ERR_CRASHED; + + DBUG_RETURN(my_errno); +} /* mi_delete */ + + + /* Remove a key from the btree index */ + +int _mi_ck_delete(register MI_INFO *info, uint keynr, uchar *key, + uint key_length) +{ + int error; + uint nod_flag; + my_off_t old_root; + uchar *root_buff; + MI_KEYDEF *keyinfo; + DBUG_ENTER("_mi_ck_delete"); + + if ((old_root=info->s->state.key_root[keynr]) == HA_OFFSET_ERROR) + { + DBUG_RETURN(my_errno=HA_ERR_CRASHED); + } + keyinfo=info->s->keyinfo+keynr; + if (!(root_buff= (uchar*) my_alloca((uint) keyinfo->block_length+ + MI_MAX_KEY_BUFF*2))) + { + DBUG_PRINT("error",("Couldn't allocate memory")); + DBUG_RETURN(my_errno=ENOMEM); + } + DBUG_PRINT("info",("root_page: %ld",old_root)); + if (!_mi_fetch_keypage(info,keyinfo,old_root,root_buff,0)) + { + error= -1; + goto err; + } + if ((error=d_search(info,keyinfo,key,key_length,old_root,root_buff)) >0) + { + if (error == 2) + { + DBUG_PRINT("test",("Enlarging of root when deleting")); + error=_mi_enlarge_root(info,keynr,key); + } + else /* error == 1 */ + { + if (mi_getint(root_buff) <= (nod_flag=mi_test_if_nod(root_buff))+3) + { + error=0; + if (nod_flag) + info->s->state.key_root[keynr]=_mi_kpos(nod_flag, + root_buff+2+nod_flag); + else + info->s->state.key_root[keynr]= HA_OFFSET_ERROR; + if (_mi_dispose(info,keyinfo,old_root)) + error= -1; + } + else + error=_mi_write_keypage(info,keyinfo,old_root,root_buff); + } + } +err: + my_afree((gptr) root_buff); + DBUG_RETURN(error); +} /* _mi_ck_delete */ + + + /* + ** Remove key below key root + ** Return values: + ** 1 if there are less buffers; In this case anc_buff is not saved + ** 2 if there are more buffers + ** -1 on errors + */ + +static int d_search(register MI_INFO *info, register MI_KEYDEF *keyinfo, + uchar *key, uint key_length, my_off_t page, + uchar *anc_buff) +{ + int flag,ret_value,save_flag; + uint length,nod_flag; + my_bool last_key; + uchar *leaf_buff,*keypos; + my_off_t leaf_page,next_block; + uchar lastkey[MI_MAX_KEY_BUFF]; + DBUG_ENTER("d_search"); + DBUG_DUMP("page",(byte*) anc_buff,mi_getint(anc_buff)); + + flag=(*keyinfo->bin_search)(info,keyinfo,anc_buff,key,key_length,SEARCH_SAME, + &keypos, lastkey, &last_key); + if (flag == MI_FOUND_WRONG_KEY) + { + DBUG_PRINT("error",("Found wrong key")); + DBUG_RETURN(-1); + } + nod_flag=mi_test_if_nod(anc_buff); + + leaf_buff=0; + LINT_INIT(leaf_page); + if (nod_flag) + { + leaf_page=_mi_kpos(nod_flag,keypos); + if (!(leaf_buff= (uchar*) my_alloca((uint) keyinfo->block_length+ + MI_MAX_KEY_BUFF*2))) + { + DBUG_PRINT("error",("Couldn't allocate memory")); + my_errno=ENOMEM; + DBUG_RETURN(-1); + } + if (!_mi_fetch_keypage(info,keyinfo,leaf_page,leaf_buff,0)) + goto err; + } + + if (flag != 0) + { + if (!nod_flag) + { + DBUG_PRINT("error",("Didn't find key")); + my_errno=HA_ERR_CRASHED; /* This should newer happend */ + goto err; + } + save_flag=0; + ret_value=d_search(info,keyinfo,key,key_length,leaf_page,leaf_buff); + } + else + { /* Found key */ + uint tmp; + length=mi_getint(anc_buff); + tmp=remove_key(keyinfo,nod_flag,keypos,lastkey,anc_buff+length, + &next_block); + if (tmp == 0) + DBUG_RETURN(0); + length-= tmp; + + mi_putint(anc_buff,length,nod_flag); + if (!nod_flag) + { /* On leaf page */ + if (_mi_write_keypage(info,keyinfo,page,anc_buff)) + DBUG_RETURN(-1); + if (length <= (uint) keyinfo->underflow_block_length) + DBUG_RETURN(1); /* Page will be update later */ + DBUG_RETURN(0); + } + save_flag=1; + ret_value=del(info,keyinfo,key,anc_buff,leaf_page,leaf_buff,keypos, + next_block,lastkey); + } + if (ret_value >0) + { + save_flag=1; + if (ret_value == 1) + ret_value= underflow(info,keyinfo,anc_buff,leaf_page,leaf_buff,keypos); + else + { /* This happens only with packed keys */ + DBUG_PRINT("test",("Enlarging of key when deleting")); + if (!_mi_get_last_key(info,keyinfo,anc_buff,lastkey,keypos,&length)) + { + goto err; + } + ret_value=_mi_insert(info,keyinfo,key,anc_buff,keypos,lastkey, + (uchar*) 0,(uchar*) 0,(my_off_t) 0,(my_bool) 0); + } + } + if (ret_value == 0 && mi_getint(anc_buff) > keyinfo->block_length) + { + save_flag=1; + ret_value=_mi_split_page(info,keyinfo,key,anc_buff,lastkey,0) | 2; + } + if (save_flag && ret_value != 1) + ret_value|=_mi_write_keypage(info,keyinfo,page,anc_buff); + else + { + DBUG_DUMP("page",(byte*) anc_buff,mi_getint(anc_buff)); + } + my_afree((byte*) leaf_buff); + DBUG_RETURN(ret_value); +err: + my_afree((byte*) leaf_buff); + DBUG_PRINT("exit",("Error: %d",my_errno)); + DBUG_RETURN (-1); +} /* d_search */ + + + /* Remove a key that has a page-reference */ + +static int del(register MI_INFO *info, register MI_KEYDEF *keyinfo, uchar *key, + uchar *anc_buff, my_off_t leaf_page, uchar *leaf_buff, + uchar *keypos, /* Pos to where deleted key was */ + my_off_t next_block, + uchar *ret_key) /* key before keypos in anc_buff */ +{ + int ret_value,length; + uint a_length,nod_flag,tmp; + my_off_t next_page; + uchar keybuff[MI_MAX_KEY_BUFF],*endpos,*next_buff,*key_start, *prev_key; + MYISAM_SHARE *share=info->s; + MI_KEY_PARAM s_temp; + DBUG_ENTER("del"); + DBUG_PRINT("enter",("leaf_page: %ld keypos: %lx",leaf_page,keypos)); + DBUG_DUMP("leaf_buff",(byte*) leaf_buff,mi_getint(leaf_buff)); + + endpos=leaf_buff+mi_getint(leaf_buff); + if (!(key_start=_mi_get_last_key(info,keyinfo,leaf_buff,keybuff,endpos, + &tmp))) + DBUG_RETURN(-1); + + if ((nod_flag=mi_test_if_nod(leaf_buff))) + { + next_page= _mi_kpos(nod_flag,endpos); + if (!(next_buff= (uchar*) my_alloca((uint) keyinfo->block_length+ + MI_MAX_KEY_BUFF*2))) + DBUG_RETURN(-1); + if (!_mi_fetch_keypage(info,keyinfo,next_page,next_buff,0)) + ret_value= -1; + else + { + DBUG_DUMP("next_page",(byte*) next_buff,mi_getint(next_buff)); + if ((ret_value=del(info,keyinfo,key,anc_buff,next_page,next_buff, + keypos,next_block,ret_key)) >0) + { + endpos=leaf_buff+mi_getint(leaf_buff); + if (ret_value == 1) + { + ret_value=underflow(info,keyinfo,leaf_buff,next_page, + next_buff,endpos); + if (ret_value == 0 && mi_getint(leaf_buff) > keyinfo->block_length) + { + ret_value=_mi_split_page(info,keyinfo,key,leaf_buff,ret_key,0) | 2; + } + } + else + { + DBUG_PRINT("test",("Inserting of key when deleting")); + if (_mi_get_last_key(info,keyinfo,leaf_buff,keybuff,endpos, + &tmp)) + goto err; + ret_value=_mi_insert(info,keyinfo,key,leaf_buff,endpos,keybuff, + (uchar*) 0,(uchar*) 0,(my_off_t) 0,0); + } + } + if (_mi_write_keypage(info,keyinfo,leaf_page,leaf_buff)) + goto err; + } + my_afree((byte*) next_buff); + DBUG_RETURN(ret_value); + } + + /* Remove last key from leaf page */ + + mi_putint(leaf_buff,key_start-leaf_buff,nod_flag); + if (_mi_write_keypage(info,keyinfo,leaf_page,leaf_buff)) + goto err; + + /* Place last key in ancestor page on deleted key position */ + + a_length=mi_getint(anc_buff); + endpos=anc_buff+a_length; + if (keypos != anc_buff+2+share->base.key_reflength && + !_mi_get_last_key(info,keyinfo,anc_buff,ret_key,keypos,&tmp)) + goto err; + prev_key=(keypos == anc_buff+2+share->base.key_reflength ? + 0 : ret_key); + length=(*keyinfo->pack_key)(keyinfo,share->base.key_reflength, + keypos == endpos ? (uchar*) 0 : keypos, + prev_key, prev_key, + keybuff,&s_temp); + if (length > 0) + bmove_upp((byte*) endpos+length,(byte*) endpos,(uint) (endpos-keypos)); + else + bmove(keypos,keypos-length, (int) (endpos-keypos)+length); + (*keyinfo->store_key)(keyinfo,keypos,&s_temp); + /* Save pointer to next leaf */ + if (!(*keyinfo->get_key)(keyinfo,share->base.key_reflength,&keypos,ret_key)) + goto err; + _mi_kpointer(info,keypos - share->base.key_reflength,next_block); + mi_putint(anc_buff,a_length+length,share->base.key_reflength); + + DBUG_RETURN( mi_getint(leaf_buff) <= (uint) keyinfo->underflow_block_length); +err: + DBUG_RETURN(-1); +} /* del */ + + + /* Balances adjacent pages if underflow occours */ + +static int underflow(register MI_INFO *info, register MI_KEYDEF *keyinfo, + uchar *anc_buff, + my_off_t leaf_page,/* Ancestor page and underflow page */ + uchar *leaf_buff, + uchar *keypos) /* Position to pos after key */ +{ + int t_length; + uint length,anc_length,buff_length,leaf_length,p_length,s_length,nod_flag, + key_reflength,key_length; + my_off_t next_page; + uchar anc_key[MI_MAX_KEY_BUFF],leaf_key[MI_MAX_KEY_BUFF], + *buff,*endpos,*next_keypos,*anc_pos,*half_pos,*temp_pos,*prev_key, + *after_key; + MI_KEY_PARAM s_temp; + MYISAM_SHARE *share=info->s; + DBUG_ENTER("underflow"); + DBUG_PRINT("enter",("leaf_page: %ld keypos: %lx",(long) leaf_page,keypos)); + DBUG_DUMP("anc_buff",(byte*) anc_buff,mi_getint(anc_buff)); + DBUG_DUMP("leaf_buff",(byte*) leaf_buff,mi_getint(leaf_buff)); + + buff=info->buff; + info->buff_used=1; + next_keypos=keypos; + nod_flag=mi_test_if_nod(leaf_buff); + p_length=nod_flag+2; + anc_length=mi_getint(anc_buff); + leaf_length=mi_getint(leaf_buff); + key_reflength=share->base.key_reflength; + if (info->s->keyinfo+info->lastinx == keyinfo) + info->page_changed=1; + + if ((keypos < anc_buff+anc_length && (share->rnd++ & 1)) || + keypos == anc_buff+2+key_reflength) + { /* Use page right of anc-page */ + DBUG_PRINT("test",("use right page")); + + if (keyinfo->flag & HA_BINARY_PACK_KEY) + { + if (!(next_keypos=_mi_get_key(info, keyinfo, + anc_buff, buff, keypos, &length))) + goto err; + } + else + { + /* Got to end of found key */ + buff[0]=buff[1]=0; /* Avoid length error check if packed key */ + if (!(*keyinfo->get_key)(keyinfo,key_reflength,&next_keypos, + buff)) + goto err; + } + next_page= _mi_kpos(key_reflength,next_keypos); + if (!_mi_fetch_keypage(info,keyinfo,next_page,buff,0)) + goto err; + buff_length=mi_getint(buff); + DBUG_DUMP("next",(byte*) buff,buff_length); + + /* find keys to make a big key-page */ + bmove((byte*) next_keypos-key_reflength,(byte*) buff+2, + key_reflength); + if (!_mi_get_last_key(info,keyinfo,anc_buff,anc_key,next_keypos,&length) + || !_mi_get_last_key(info,keyinfo,leaf_buff,leaf_key, + leaf_buff+leaf_length,&length)) + goto err; + + /* merge pages and put parting key from anc_buff between */ + prev_key=(leaf_length == p_length ? (uchar*) 0 : leaf_key); + t_length=(*keyinfo->pack_key)(keyinfo,nod_flag,buff+p_length, + prev_key, prev_key, + anc_key, &s_temp); + length=buff_length-p_length; + endpos=buff+length+leaf_length+t_length; + /* buff will always be larger than before !*/ + bmove_upp((byte*) endpos, (byte*) buff+buff_length,length); + memcpy((byte*) buff, (byte*) leaf_buff,(size_t) leaf_length); + (*keyinfo->store_key)(keyinfo,buff+leaf_length,&s_temp); + buff_length=(uint) (endpos-buff); + mi_putint(buff,buff_length,nod_flag); + + /* remove key from anc_buff */ + + s_length=remove_key(keyinfo,key_reflength,keypos,anc_key, + anc_buff+anc_length,(my_off_t *) 0); + if (!s_length) + goto err; + anc_length-=s_length; + mi_putint(anc_buff,anc_length,key_reflength); + + if (buff_length <= keyinfo->block_length) + { /* Keys in one page */ + memcpy((byte*) leaf_buff,(byte*) buff,(size_t) buff_length); + if (_mi_dispose(info,keyinfo,next_page)) + goto err; + } + else + { /* Page is full */ + endpos=anc_buff+anc_length; + DBUG_PRINT("test",("anc_buff: %lx endpos: %lx",anc_buff,endpos)); + if (keypos != anc_buff+2+key_reflength && + !_mi_get_last_key(info,keyinfo,anc_buff,anc_key,keypos,&length)) + goto err; + if (!(half_pos=_mi_find_half_pos(nod_flag, keyinfo, buff, leaf_key, + &key_length, &after_key))) + goto err; + length=(uint) (half_pos-buff); + memcpy((byte*) leaf_buff,(byte*) buff,(size_t) length); + mi_putint(leaf_buff,length,nod_flag); + + /* Correct new keypointer to leaf_page */ + half_pos=after_key; + _mi_kpointer(info,leaf_key+key_length,next_page); + /* Save key in anc_buff */ + prev_key=(keypos == anc_buff+2+key_reflength ? (uchar*) 0 : anc_key), + t_length=(*keyinfo->pack_key)(keyinfo,key_reflength, + (keypos == endpos ? (uchar*) 0 : + keypos), + prev_key, prev_key, + leaf_key, &s_temp); + if (t_length >= 0) + bmove_upp((byte*) endpos+t_length,(byte*) endpos, + (uint) (endpos-keypos)); + else + bmove(keypos,keypos-t_length,(uint) (endpos-keypos)+t_length); + (*keyinfo->store_key)(keyinfo,keypos,&s_temp); + mi_putint(anc_buff,(anc_length+=t_length),key_reflength); + + /* Store key first in new page */ + if (nod_flag) + bmove((byte*) buff+2,(byte*) half_pos-nod_flag,(size_t) nod_flag); + if (!(*keyinfo->get_key)(keyinfo,nod_flag,&half_pos,leaf_key)) + goto err; + t_length=(int) (*keyinfo->pack_key)(keyinfo, nod_flag, (uchar*) 0, + (uchar*) 0, (uchar *) 0, + leaf_key, &s_temp); + /* t_length will always be > 0 for a new page !*/ + length=(buff+mi_getint(buff))-half_pos; + bmove((byte*) buff+p_length+t_length,(byte*) half_pos,(size_t) length); + (*keyinfo->store_key)(keyinfo,buff+p_length,&s_temp); + mi_putint(buff,length+t_length+p_length,nod_flag); + + if (_mi_write_keypage(info,keyinfo,next_page,buff)) + goto err; + } + if (_mi_write_keypage(info,keyinfo,leaf_page,leaf_buff)) + goto err; + DBUG_RETURN(anc_length <= (uint) keyinfo->underflow_block_length); + } + + DBUG_PRINT("test",("use left page")); + + keypos=_mi_get_last_key(info,keyinfo,anc_buff,anc_key,keypos,&length); + if (!keypos) + goto err; + next_page= _mi_kpos(key_reflength,keypos); + if (!_mi_fetch_keypage(info,keyinfo,next_page,buff,0)) + goto err; + buff_length=mi_getint(buff); + endpos=buff+buff_length; + DBUG_DUMP("prev",(byte*) buff,buff_length); + + /* find keys to make a big key-page */ + bmove((byte*) next_keypos - key_reflength,(byte*) leaf_buff+2, + key_reflength); + next_keypos=keypos; + if (!(*keyinfo->get_key)(keyinfo,key_reflength,&next_keypos, + anc_key)) + goto err; + if (!_mi_get_last_key(info,keyinfo,buff,leaf_key,endpos,&length)) + goto err; + + /* merge pages and put parting key from anc_buff between */ + prev_key=(leaf_length == p_length ? (uchar*) 0 : leaf_key); + t_length=(*keyinfo->pack_key)(keyinfo,nod_flag, + (leaf_length == p_length ? + (uchar*) 0 : leaf_buff+p_length), + prev_key, prev_key, + anc_key, &s_temp); + if (t_length >= 0) + bmove((byte*) endpos+t_length,(byte*) leaf_buff+p_length, + (size_t) (leaf_length-p_length)); + else /* We gained space */ + bmove((byte*) endpos,(byte*) leaf_buff+((int) p_length-t_length), + (size_t) (leaf_length-p_length+t_length)); + + (*keyinfo->store_key)(keyinfo,endpos,&s_temp); + buff_length=buff_length+leaf_length-p_length+t_length; + mi_putint(buff,buff_length,nod_flag); + + /* remove key from anc_buff */ + s_length=remove_key(keyinfo,key_reflength,keypos,anc_key, + anc_buff+anc_length,(my_off_t *) 0); + if (!s_length) + goto err; + anc_length-=s_length; + mi_putint(anc_buff,anc_length,key_reflength); + + if (buff_length <= keyinfo->block_length) + { /* Keys in one page */ + if (_mi_dispose(info,keyinfo,leaf_page)) + goto err; + } + else + { /* Page is full */ + if (keypos == anc_buff+2+key_reflength) + anc_pos=0; /* First key */ + else if (!_mi_get_last_key(info,keyinfo,anc_buff,anc_pos=anc_key,keypos, + &length)) + goto err; + endpos=_mi_find_half_pos(nod_flag,keyinfo,buff,leaf_key, + &key_length, &half_pos); + if (!endpos) + goto err; + _mi_kpointer(info,leaf_key+key_length,leaf_page); + /* Save key in anc_buff */ + DBUG_DUMP("anc_buff",(byte*) anc_buff,anc_length); + DBUG_DUMP("key_to_anc",(byte*) leaf_key,key_length); + + temp_pos=anc_buff+anc_length; + t_length=(*keyinfo->pack_key)(keyinfo,key_reflength, + keypos == temp_pos ? (uchar*) 0 + : keypos, + anc_pos, anc_pos, + leaf_key,&s_temp); + if (t_length > 0) + bmove_upp((byte*) temp_pos+t_length,(byte*) temp_pos, + (uint) (temp_pos-keypos)); + else + bmove(keypos,keypos-t_length,(uint) (temp_pos-keypos)+t_length); + (*keyinfo->store_key)(keyinfo,keypos,&s_temp); + mi_putint(anc_buff,(anc_length+=t_length),key_reflength); + + /* Store first key on new page */ + if (nod_flag) + bmove((byte*) leaf_buff+2,(byte*) half_pos-nod_flag,(size_t) nod_flag); + if (!(length=(*keyinfo->get_key)(keyinfo,nod_flag,&half_pos,leaf_key))) + goto err; + DBUG_DUMP("key_to_leaf",(byte*) leaf_key,length); + t_length=(*keyinfo->pack_key)(keyinfo,nod_flag, (uchar*) 0, + (uchar*) 0, (uchar*) 0, leaf_key, &s_temp); + length=(uint) ((buff+buff_length)-half_pos); + DBUG_PRINT("info",("t_length: %d length: %d",t_length,(int) length)); + bmove((byte*) leaf_buff+p_length+t_length,(byte*) half_pos, + (size_t) length); + (*keyinfo->store_key)(keyinfo,leaf_buff+p_length,&s_temp); + mi_putint(leaf_buff,length+t_length+p_length,nod_flag); + if (_mi_write_keypage(info,keyinfo,leaf_page,leaf_buff)) + goto err; + mi_putint(buff,endpos-buff,nod_flag); + } + if (_mi_write_keypage(info,keyinfo,next_page,buff)) + goto err; + DBUG_RETURN(anc_length <= (uint) keyinfo->block_length/2); +err: + DBUG_RETURN(-1); +} /* underflow */ + + + /* + remove a key from packed buffert + The current code doesn't handle the case that the next key may be + packed better against the previous key if there is a case difference + returns how many chars was removed or 0 on error + */ + +static uint remove_key(MI_KEYDEF *keyinfo, uint nod_flag, + uchar *keypos, /* Where key starts */ + uchar *lastkey, /* key to be removed */ + uchar *page_end, /* End of page */ + my_off_t *next_block) /* ptr to next block */ +{ + int s_length; + uchar *start; + DBUG_ENTER("remove_key"); + DBUG_PRINT("enter",("keypos: %lx page_end: %lx",keypos,page_end)); + + start=keypos; + if (!(keyinfo->flag & + (HA_PACK_KEY | HA_SPACE_PACK_USED | HA_VAR_LENGTH_KEY | + HA_BINARY_PACK_KEY))) + { + s_length=(int) (keyinfo->keylength+nod_flag); + if (next_block && nod_flag) + *next_block= _mi_kpos(nod_flag,keypos+s_length); + } + else + { /* Let keypos point at next key */ + /* Calculate length of key */ + if (!(*keyinfo->get_key)(keyinfo,nod_flag,&keypos,lastkey)) + DBUG_RETURN(0); /* Error */ + if (next_block && nod_flag) + *next_block= _mi_kpos(nod_flag,keypos); + s_length=(keypos-start); + if (keypos != page_end) + { + if (keyinfo->flag & HA_BINARY_PACK_KEY) + { + uchar *old_key=start; + uint next_length,prev_length,prev_pack_length; + get_key_length(next_length,keypos); + get_key_pack_length(prev_length,prev_pack_length,old_key); + if (next_length > prev_length) + { + /* We have to copy data from the current key to the next key */ + bmove_upp((char*) keypos,(char*) (lastkey+next_length), + (next_length-prev_length)); + keypos-=(next_length-prev_length)+prev_pack_length; + store_key_length(keypos,prev_length); + s_length=(keypos-start); + } + } + else + { + /* A variable length first key part */ + if (*keypos & 128) /* Next key is packed */ + { + uint next_length,prev_length,prev_pack_length,lastkey_length, + rest_length; + if (keyinfo->seg[0].length >= 127) + { + if (!(prev_length=mi_uint2korr(start) & 32767)) + goto end; + next_length=mi_uint2korr(keypos) & 32767; + keypos+=2; + prev_pack_length=2; + } + else + { + if (!(prev_length= *start & 127)) + goto end; /* Same key as previous*/ + next_length= *keypos & 127; + keypos++; + prev_pack_length=1; + } + if (!(*start & 128)) + prev_length=0; /* prev key not packed */ + if (keyinfo->seg[0].flag & HA_NULL_PART) + lastkey++; /* Skipp null marker */ + get_key_length(lastkey_length,lastkey); + if (!next_length) /* Same key after */ + { + next_length=lastkey_length; + rest_length=0; + } + else + get_key_length(rest_length,keypos); + + if (next_length > prev_length) + { /* Key after is based on deleted key */ + uint pack_length,tmp; + bmove_upp((char*) keypos,(char*) (lastkey+next_length), + tmp=(next_length-prev_length)); + rest_length+=tmp; + pack_length= prev_length ? get_pack_length(rest_length): 0; + keypos-=tmp+pack_length+prev_pack_length; + s_length=(keypos-start); + if (prev_length) /* Pack against prev key */ + { + *keypos++= start[0]; + if (prev_pack_length == 2) + *keypos++= start[1]; + store_key_length(keypos,rest_length); + } + else + { + /* Next key is not packed anymore */ + if (keyinfo->seg[0].flag & HA_NULL_PART) + { + rest_length++; /* Mark not null */ + } + if (prev_pack_length == 2) + { + mi_int2store(keypos,rest_length); + } + else + *keypos= rest_length; + } + } + } + } + } + } + end: + bmove((byte*) start,(byte*) start+s_length, + (uint) (page_end-start-s_length)); + DBUG_RETURN((uint) s_length); +} /* remove_key */ |