mi_delete_all.c
上传用户:romrleung
上传日期:2022-05-23
资源大小:18897k
文件大小:3k
- /* 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 all rows from a MyISAM table */
- /* This clears the status information and truncates files */
- #include "myisamdef.h"
- int mi_delete_all_rows(MI_INFO *info)
- {
- uint i;
- MYISAM_SHARE *share=info->s;
- MI_STATE_INFO *state=&share->state;
- DBUG_ENTER("mi_delete_all_rows");
- 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 (_mi_mark_file_changed(info))
- goto err;
- info->state->records=info->state->del=state->split=0;
- state->dellink = HA_OFFSET_ERROR;
- state->sortkey= (ushort) ~0;
- info->state->key_file_length=share->base.keystart;
- info->state->data_file_length=0;
- info->state->empty=info->state->key_empty=0;
- state->checksum=0;
- for (i=share->base.max_key_block_length/MI_MIN_KEY_BLOCK_LENGTH ; i-- ; )
- state->key_del[i]= HA_OFFSET_ERROR;
- for (i=0 ; i < share->base.keys ; i++)
- state->key_root[i]= HA_OFFSET_ERROR;
- myisam_log_command(MI_LOG_DELETE_ALL,info,(byte*) 0,0,0);
- /*
- If we are using delayed keys or if the user has done changes to the tables
- since it was locked then there may be key blocks in the key cache
- */
- flush_key_blocks(share->key_cache, share->kfile, FLUSH_IGNORE_CHANGED);
- if (my_chsize(info->dfile, 0, 0, MYF(MY_WME)) ||
- my_chsize(share->kfile, share->base.keystart, 0, MYF(MY_WME)) )
- goto err;
- VOID(_mi_writeinfo(info,WRITEINFO_UPDATE_KEYFILE));
- allow_break(); /* Allow SIGHUP & SIGINT */
- DBUG_RETURN(0);
- err:
- {
- int save_errno=my_errno;
- VOID(_mi_writeinfo(info,WRITEINFO_UPDATE_KEYFILE));
- info->update|=HA_STATE_WRITTEN; /* Buffer changed */
- allow_break(); /* Allow SIGHUP & SIGINT */
- DBUG_RETURN(my_errno=save_errno);
- }
- } /* mi_delete */