diff options
Diffstat (limited to 'myisam/mi_statrec.c')
| -rw-r--r-- | myisam/mi_statrec.c | 302 |
1 files changed, 302 insertions, 0 deletions
diff --git a/myisam/mi_statrec.c b/myisam/mi_statrec.c new file mode 100644 index 00000000000..05ff40d8921 --- /dev/null +++ b/myisam/mi_statrec.c @@ -0,0 +1,302 @@ +/* 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 */ + + /* Functions to handle fixed-length-records */ + +#include "myisamdef.h" + + +int _mi_write_static_record(MI_INFO *info, const byte *record) +{ + uchar temp[8]; /* max pointer length */ + + if (info->s->state.dellink != HA_OFFSET_ERROR) + { + my_off_t filepos=info->s->state.dellink; + info->rec_cache.seek_not_done=1; /* We have done a seek */ + VOID(my_seek(info->dfile,info->s->state.dellink+1,MY_SEEK_SET,MYF(0))); + + if (my_read(info->dfile,(char*) &temp[0],info->s->base.rec_reflength, + MYF(MY_NABP))) + goto err; + info->s->state.dellink= _mi_rec_pos(info->s,temp); + info->state->del--; + info->state->empty-=info->s->base.pack_reclength; + VOID(my_seek(info->dfile,filepos,MY_SEEK_SET,MYF(0))); + if (my_write(info->dfile, (char*) record, info->s->base.reclength, + MYF(MY_NABP))) + goto err; + } + else + { + if (info->state->data_file_length > info->s->base.max_data_file_length- + info->s->base.pack_reclength) + { + my_errno=HA_ERR_RECORD_FILE_FULL; + return(2); + } + if (info->opt_flag & WRITE_CACHE_USED) + { /* Cash in use */ + if (my_b_write(&info->rec_cache, (byte*) record, + info->s->base.reclength)) + goto err; + if (info->s->base.pack_reclength != info->s->base.reclength) + { + uint length=info->s->base.pack_reclength - info->s->base.reclength; + bzero((char*) temp,length); + if (my_b_write(&info->rec_cache, (byte*) temp,length)) + goto err; + } + } + else + { + info->rec_cache.seek_not_done=1; /* We have done a seek */ + VOID(my_seek(info->dfile,info->state->data_file_length, + MY_SEEK_SET,MYF(0))); + if (my_write(info->dfile,(char*) record,info->s->base.reclength, + info->s->write_flag)) + goto err; + if (info->s->base.pack_reclength != info->s->base.reclength) + { + uint length=info->s->base.pack_reclength - info->s->base.reclength; + bzero((char*) temp,length); + if (my_write(info->dfile, (byte*) temp,length, info->s->write_flag)) + goto err; + } + } + info->state->data_file_length+=info->s->base.pack_reclength; + info->s->state.split++; + } + return 0; + err: + return 1; +} + +int _mi_update_static_record(MI_INFO *info, my_off_t pos, const byte *record) +{ + info->rec_cache.seek_not_done=1; /* We have done a seek */ + VOID(my_seek(info->dfile,pos,MY_SEEK_SET,MYF(0))); + return (my_write(info->dfile,(char*) record,info->s->base.reclength, + MYF(MY_NABP)) != 0); +} + + +int _mi_delete_static_record(MI_INFO *info) +{ + uchar temp[9]; /* 1+sizeof(uint32) */ + + info->state->del++; + info->state->empty+=info->s->base.pack_reclength; + temp[0]= '\0'; /* Mark that record is deleted */ + _mi_dpointer(info,temp+1,info->s->state.dellink); + info->s->state.dellink = info->lastpos; + info->rec_cache.seek_not_done=1; + VOID(my_seek(info->dfile,info->lastpos,MY_SEEK_SET,MYF(0))); + return (my_write(info->dfile,(byte*) temp, 1+info->s->rec_reflength, + MYF(MY_NABP)) != 0); +} + + +int _mi_cmp_static_record(register MI_INFO *info, register const byte *old) +{ + DBUG_ENTER("_mi_cmp_static_record"); + + /* We are going to do changes; dont let anybody disturb */ + dont_break(); /* Dont allow SIGHUP or SIGINT */ + + if (info->opt_flag & WRITE_CACHE_USED) + { + if (flush_io_cache(&info->rec_cache)) + { + DBUG_RETURN(-1); + } + info->rec_cache.seek_not_done=1; /* We have done a seek */ + } + + if ((info->opt_flag & READ_CHECK_USED)) + { /* If check isn't disabled */ + info->rec_cache.seek_not_done=1; /* We have done a seek */ + VOID(my_seek(info->dfile,info->lastpos,MY_SEEK_SET,MYF(0))); + if (my_read(info->dfile, (char*) info->rec_buff, info->s->base.reclength, + MYF(MY_NABP))) + DBUG_RETURN(-1); + if (memcmp((byte*) info->rec_buff, (byte*) old, + (uint) info->s->base.reclength)) + { + DBUG_DUMP("read",old,info->s->base.reclength); + DBUG_DUMP("disk",info->rec_buff,info->s->base.reclength); + my_errno=HA_ERR_RECORD_CHANGED; /* Record have changed */ + DBUG_RETURN(1); + } + } + DBUG_RETURN(0); +} + + +int _mi_cmp_static_unique(MI_INFO *info, MI_UNIQUEDEF *def, + const byte *record, my_off_t pos) +{ + DBUG_ENTER("_mi_cmp_static_unique"); + + info->rec_cache.seek_not_done=1; /* We have done a seek */ + VOID(my_seek(info->dfile,pos,MY_SEEK_SET,MYF(0))); + if (my_read(info->dfile, (char*) info->rec_buff, info->s->base.reclength, + MYF(MY_NABP))) + DBUG_RETURN(-1); + DBUG_RETURN(mi_unique_comp(def, record, info->rec_buff, + def->null_are_equal)); +} + + + /* Read a fixed-length-record */ + /* Returns 0 if Ok. */ + /* 1 if record is deleted */ + /* MY_FILE_ERROR on read-error or locking-error */ + +int _mi_read_static_record(register MI_INFO *info, register my_off_t pos, + register byte *record) +{ + int error; + + if (pos != HA_OFFSET_ERROR) + { + if (info->opt_flag & WRITE_CACHE_USED && + info->rec_cache.pos_in_file <= pos && + flush_io_cache(&info->rec_cache)) + return(-1); + info->rec_cache.seek_not_done=1; /* We have done a seek */ + + error=my_pread(info->dfile,(char*) record,info->s->base.reclength, + pos,MYF(MY_NABP)) != 0; + if (info->s->r_locks == 0 && info->s->w_locks == 0) + VOID(_mi_writeinfo(info,0)); + if (! error) + { + if (!*record) + { + my_errno=HA_ERR_RECORD_DELETED; + return(1); /* Record is deleted */ + } + info->update|= HA_STATE_AKTIV; /* Record is read */ + return(0); + } + return(-1); /* Error on read */ + } + VOID(_mi_writeinfo(info,0)); /* No such record */ + return(-1); +} + + + +int _mi_read_rnd_static_record(MI_INFO *info, byte *buf, + register my_off_t filepos, + my_bool skipp_deleted_blocks) +{ + int locked,error,cache_read; + uint cache_length; + MYISAM_SHARE *share=info->s; + DBUG_ENTER("_mi_read_rnd_static_record"); + + cache_read=0; + cache_length=0; + if (info->opt_flag & WRITE_CACHE_USED && + (info->rec_cache.pos_in_file <= filepos || skipp_deleted_blocks) && + flush_io_cache(&info->rec_cache)) + DBUG_RETURN(my_errno); + if (info->opt_flag & READ_CACHE_USED) + { /* Cache in use */ + if (filepos == my_b_tell(&info->rec_cache) && + (skipp_deleted_blocks || !filepos)) + { + cache_read=1; /* Read record using cache */ + cache_length=(uint) (info->rec_cache.rc_end - info->rec_cache.rc_pos); + } + else + info->rec_cache.seek_not_done=1; /* Filepos is changed */ + } + locked=0; + if (info->lock_type == F_UNLCK) + { + if (filepos >= info->state->data_file_length) + { /* Test if new records */ + if (_mi_readinfo(info,F_RDLCK,0)) + DBUG_RETURN(my_errno); + locked=1; + } + else + { /* We don't nead new info */ +#ifndef UNSAFE_LOCKING + if ((! cache_read || share->base.reclength > cache_length) && + share->r_locks == 0 && share->w_locks == 0) + { /* record not in cache */ + if (my_lock(share->kfile,F_RDLCK,0L,F_TO_EOF, + MYF(MY_SEEK_NOT_DONE) | info->lock_wait)) + DBUG_RETURN(my_errno); + locked=1; + } +#else + info->tmp_lock_type=F_RDLCK; +#endif + } + } + if (filepos >= info->state->data_file_length) + { + DBUG_PRINT("test",("filepos: %ld (%ld) records: %ld del: %ld", + filepos/share->base.reclength,filepos, + info->state->records, info->state->del)); + VOID(_mi_writeinfo(info,0)); + DBUG_RETURN(my_errno=HA_ERR_END_OF_FILE); + } + info->lastpos= filepos; + info->nextpos= filepos+share->base.pack_reclength; + + if (! cache_read) /* No cacheing */ + { + if ((error=_mi_read_static_record(info,filepos,buf))) + { + if (error > 0) + error=my_errno=HA_ERR_RECORD_DELETED; + else + error=my_errno; + } + DBUG_RETURN(error); + } + + /* Read record with cacheing */ + error=my_b_read(&info->rec_cache,(byte*) buf,share->base.reclength); + if (info->s->base.pack_reclength != info->s->base.reclength && !error) + { + char tmp[8]; /* Skill fill bytes */ + error=my_b_read(&info->rec_cache,(byte*) tmp, + info->s->base.pack_reclength - info->s->base.reclength); + } + if (locked) + VOID(_mi_writeinfo(info,0)); /* Unlock keyfile */ + if (!error) + { + if (!buf[0]) + { /* Record is removed */ + DBUG_RETURN(my_errno=HA_ERR_RECORD_DELETED); + } + /* Found and may be updated */ + info->update|= HA_STATE_AKTIV | HA_STATE_KEY_CHANGED; + DBUG_RETURN(0); + } + /* my_errno should be set if rec_cache.error == -1 */ + if (info->rec_cache.error != -1 || my_errno == 0) + my_errno=HA_ERR_WRONG_IN_RECORD; + DBUG_RETURN(my_errno); /* Something wrong (EOF?) */ +} |