diff options
Diffstat (limited to 'myisam/mi_dynrec.c')
| -rw-r--r-- | myisam/mi_dynrec.c | 1537 |
1 files changed, 1537 insertions, 0 deletions
diff --git a/myisam/mi_dynrec.c b/myisam/mi_dynrec.c new file mode 100644 index 00000000000..789831db810 --- /dev/null +++ b/myisam/mi_dynrec.c @@ -0,0 +1,1537 @@ +/* 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 space-packed-records and blobs */ + +#include "myisamdef.h" + +/* Enough for comparing if number is zero */ +static char zero_string[]={0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}; + +static int write_dynamic_record(MI_INFO *info,const byte *record, + ulong reclength); +static int _mi_find_writepos(MI_INFO *info,ulong reclength,my_off_t *filepos, + ulong *length); +static int update_dynamic_record(MI_INFO *info,my_off_t filepos,byte *record, + ulong reclength); +static int delete_dynamic_record(MI_INFO *info,my_off_t filepos, + uint second_read); +static int _mi_cmp_buffer(File file, const byte *buff, my_off_t filepos, + uint length); + +#ifdef THREAD +/* Play it safe; We have a small stack when using threads */ +#undef my_alloca +#undef my_afree +#define my_alloca(A) my_malloc((A),MYF(0)) +#define my_afree(A) my_free((A),MYF(0)) +#endif + + /* Interface function from MI_INFO */ + +int _mi_write_dynamic_record(MI_INFO *info, const byte *record) +{ + ulong reclength=_mi_rec_pack(info,info->rec_buff,record); + return (write_dynamic_record(info,info->rec_buff,reclength)); +} + +int _mi_update_dynamic_record(MI_INFO *info, my_off_t pos, const byte *record) +{ + uint length=_mi_rec_pack(info,info->rec_buff,record); + return (update_dynamic_record(info,pos,info->rec_buff,length)); +} + +int _mi_write_blob_record(MI_INFO *info, const byte *record) +{ + byte *rec_buff; + int error; + ulong reclength,extra; + + extra=ALIGN_SIZE(MI_MAX_DYN_BLOCK_HEADER)+MI_SPLIT_LENGTH+ + MI_DYN_DELETE_BLOCK_HEADER+1; + reclength=info->s->base.pack_reclength+ + _my_calc_total_blob_length(info,record)+ extra; + if (reclength > MI_DYN_MAX_ROW_LENGTH) + { + my_errno=HA_ERR_TO_BIG_ROW; + return -1; + } + if (!(rec_buff=(byte*) my_alloca(reclength))) + { + my_errno=ENOMEM; + return(-1); + } + reclength=_mi_rec_pack(info,rec_buff+ALIGN_SIZE(MI_MAX_DYN_BLOCK_HEADER), + record); + error=write_dynamic_record(info,rec_buff+ALIGN_SIZE(MI_MAX_DYN_BLOCK_HEADER), + reclength); + my_afree(rec_buff); + return(error); +} + + +int _mi_update_blob_record(MI_INFO *info, my_off_t pos, const byte *record) +{ + byte *rec_buff; + int error; + ulong reclength,extra; + + extra=ALIGN_SIZE(MI_MAX_DYN_BLOCK_HEADER)+MI_SPLIT_LENGTH+ + MI_DYN_DELETE_BLOCK_HEADER; + reclength=info->s->base.pack_reclength+ + _my_calc_total_blob_length(info,record)+ extra; + if (reclength > MI_DYN_MAX_ROW_LENGTH) + { + my_errno=HA_ERR_TO_BIG_ROW; + return -1; + } + if (!(rec_buff=(byte*) my_alloca(reclength))) + { + my_errno=ENOMEM; + return(-1); + } + reclength=_mi_rec_pack(info,rec_buff+ALIGN_SIZE(MI_MAX_DYN_BLOCK_HEADER), + record); + error=update_dynamic_record(info,pos, + rec_buff+ALIGN_SIZE(MI_MAX_DYN_BLOCK_HEADER), + reclength); + my_afree(rec_buff); + return(error); +} + + +int _mi_delete_dynamic_record(MI_INFO *info) +{ + return delete_dynamic_record(info,info->lastpos,0); +} + + + /* Write record to data-file */ + +static int write_dynamic_record(MI_INFO *info, const byte *record, + ulong reclength) +{ + int flag; + ulong length; + my_off_t filepos; + DBUG_ENTER("write_dynamic_record"); + + flag=0; + while (reclength) + { + if (_mi_find_writepos(info,reclength,&filepos,&length)) + goto err; + if (_mi_write_part_record(info,filepos,length,info->s->state.dellink, + (byte**) &record,&reclength,&flag)) + goto err; + } + + DBUG_RETURN(0); + err: + DBUG_RETURN(1); +} + + + /* Get a block for data ; The given data-area must be used !! */ + +static int _mi_find_writepos(MI_INFO *info, + ulong reclength, /* record length */ + my_off_t *filepos, /* Return file pos */ + ulong *length) /* length of block at filepos */ +{ + MI_BLOCK_INFO block_info; + DBUG_ENTER("_mi_find_writepos"); + + if (info->s->state.dellink != HA_OFFSET_ERROR) + { + /* Deleted blocks exists; Get last used block */ + + *filepos=info->s->state.dellink; + block_info.second_read=0; + info->rec_cache.seek_not_done=1; + if (!(_mi_get_block_info(&block_info,info->dfile,info->s->state.dellink) & + BLOCK_DELETED)) + { + DBUG_PRINT("error",("Delete link crashed")); + my_errno=HA_ERR_WRONG_IN_RECORD; + DBUG_RETURN(-1); + } + info->s->state.dellink=block_info.next_filepos; + info->state->del--; + info->state->empty-= block_info.block_len; + *length= block_info.block_len; + } + else + { + /* No deleted blocks; Allocate a new block */ + *filepos=info->state->data_file_length; + if ((*length=reclength+3 + test(reclength > 65520)) < + info->s->base.min_block_length) + *length=info->s->base.min_block_length; + else + *length= ((*length+MI_DYN_ALIGN_SIZE-1) & + (~ (ulong) (MI_DYN_ALIGN_SIZE-1))); + if (info->state->data_file_length > + (info->s->base.max_data_file_length- *length)) + { + my_errno=HA_ERR_RECORD_FILE_FULL; + DBUG_RETURN(-1); + } + info->state->data_file_length+= *length; + info->s->state.split++; + info->update|=HA_STATE_WRITE_AT_END; + } + DBUG_RETURN(0); +} /* _mi_find_writepos */ + + + +/* Remove a deleted block from the deleted list */ + +static bool unlink_deleted_block(MI_INFO *info, MI_BLOCK_INFO *block_info) +{ + DBUG_ENTER("unlink_deleted_block"); + if (block_info->filepos == info->s->state.dellink) + { + /* First deleted block; We can just use this ! */ + info->s->state.dellink=block_info->next_filepos; + } + else + { + MI_BLOCK_INFO tmp; + tmp.second_read=0; + if (!(_mi_get_block_info(&tmp,info->dfile,block_info->prev_filepos) + & BLOCK_DELETED)) + DBUG_RETURN(1); /* Something is wrong */ + mi_sizestore(tmp.header+4,block_info->next_filepos); + if (my_pwrite(info->dfile,(char*) tmp.header+4,8, + block_info->prev_filepos+4, MYF(MY_NABP))) + DBUG_RETURN(1); + if (block_info->next_filepos != HA_OFFSET_ERROR) + { + if (!(_mi_get_block_info(&tmp,info->dfile,block_info->next_filepos) + & BLOCK_DELETED)) + DBUG_RETURN(1); /* Something is wrong */ + mi_sizestore(tmp.header+12,block_info->prev_filepos); + if (my_pwrite(info->dfile,(char*) tmp.header+12,8, + block_info->next_filepos+12, + MYF(MY_NABP))) + DBUG_RETURN(1); + } + } + info->state->del--; + info->state->empty-= block_info->block_len; + info->s->state.split--; + + /* Removing block that we are using through mi_rrnd */ + if (info->nextpos == block_info->filepos) + info->nextpos+=block_info->block_len; + DBUG_RETURN(0); +} + + /* Delete datarecord from database */ + /* info->rec_cache.seek_not_done is updated in cmp_record */ + +static int delete_dynamic_record(MI_INFO *info, my_off_t filepos, + uint second_read) +{ + uint length,b_type; + MI_BLOCK_INFO block_info,del_block; + int error=0; + my_bool remove_next_block; + DBUG_ENTER("delete_dynamic_record"); + + /* First add a link from the last block to the new one */ + if (info->s->state.dellink != HA_OFFSET_ERROR) + { + block_info.second_read=0; + if (_mi_get_block_info(&block_info,info->dfile,info->s->state.dellink) + & BLOCK_DELETED) + { + char buff[8]; + mi_sizestore(buff,filepos); + if (my_pwrite(info->dfile,buff,8,info->s->state.dellink+12, + MYF(MY_NABP))) + error=1; /* Error on write */ + } + else + { + error=1; /* Wrong delete link */ + my_errno=HA_ERR_WRONG_IN_RECORD; + } + } + + block_info.second_read=second_read; + do + { + /* Remove block at 'filepos' */ + if ((b_type=_mi_get_block_info(&block_info,info->dfile,filepos)) + & (BLOCK_DELETED | BLOCK_ERROR | BLOCK_SYNC_ERROR | + BLOCK_FATAL_ERROR) || + (length=(uint) (block_info.filepos-filepos) +block_info.block_len) < + MI_MIN_BLOCK_LENGTH) + { + my_errno=HA_ERR_WRONG_IN_RECORD; + DBUG_RETURN(1); + } + /* Check if next block is a delete block */ + del_block.second_read=0; + remove_next_block=0; + if (_mi_get_block_info(&del_block,info->dfile,filepos+length) & + BLOCK_DELETED && del_block.block_len+length < MI_DYN_MAX_BLOCK_LENGTH) + { + /* We can't remove this yet as this block may be the head block */ + remove_next_block=1; + length+=del_block.block_len; + } + + block_info.header[0]=0; + mi_int3store(block_info.header+1,length); + mi_sizestore(block_info.header+4,info->s->state.dellink); + if (b_type & BLOCK_LAST) + bfill(block_info.header+12,8,255); + else + mi_sizestore(block_info.header+12,block_info.next_filepos); + if (my_pwrite(info->dfile,(byte*) block_info.header,20,filepos, + MYF(MY_NABP))) + DBUG_RETURN(1); + info->s->state.dellink = filepos; + info->state->del++; + info->state->empty+=length; + filepos=block_info.next_filepos; + + /* Now it's safe to unlink the block */ + if (remove_next_block && unlink_deleted_block(info,&del_block)) + error=1; + } while (!(b_type & BLOCK_LAST)); + + DBUG_RETURN(error); +} + + + /* Write a block to datafile */ + +int _mi_write_part_record(MI_INFO *info, + my_off_t filepos, /* points at empty block */ + ulong length, /* length of block */ + my_off_t next_filepos,/* Next empty block */ + byte **record, /* pointer to record ptr */ + ulong *reclength, /* length of *record */ + int *flag) /* *flag == 0 if header */ +{ + ulong head_length,res_length,extra_length,long_block,del_length; + byte *pos,*record_end; + my_off_t next_delete_block; + uchar temp[MI_SPLIT_LENGTH+MI_DYN_DELETE_BLOCK_HEADER]; + DBUG_ENTER("_mi_write_part_record"); + + next_delete_block=HA_OFFSET_ERROR; + + res_length=extra_length=0; + if (length > *reclength + MI_SPLIT_LENGTH) + { /* Splitt big block */ + res_length=MY_ALIGN(length- *reclength - MI_EXTEND_BLOCK_LENGTH, + MI_DYN_ALIGN_SIZE); + length-= res_length; /* Use this for first part */ + } + long_block= (length < 65520L && *reclength < 65520L) ? 0 : 1; + if (length == *reclength+ 3 + long_block) + { + /* Block is exactly of the right length */ + temp[0]=(uchar) (1+ *flag)+(uchar) long_block; /* Flag is 0 or 6 */ + if (long_block) + { + mi_int3store(temp+1,*reclength); + head_length=4; + } + else + { + mi_int2store(temp+1,*reclength); + head_length=3; + } + } + else if (length-long_block < *reclength+4) + { /* To short block */ + if (next_filepos == HA_OFFSET_ERROR) + next_filepos=info->s->state.dellink != HA_OFFSET_ERROR ? + info->s->state.dellink : info->state->data_file_length; + if (*flag == 0) /* First block */ + { + head_length=5+8+long_block*2; + temp[0]=5+(uchar) long_block; + if (long_block) + { + mi_int3store(temp+1,*reclength); + mi_int3store(temp+4,length-head_length); + mi_sizestore((byte*) temp+7,next_filepos); + } + else + { + mi_int2store(temp+1,*reclength); + mi_int2store(temp+3,length-head_length); + mi_sizestore((byte*) temp+5,next_filepos); + } + } + else + { + head_length=3+8+long_block; + temp[0]=11+(uchar) long_block; + if (long_block) + { + mi_int3store(temp+1,length-head_length); + mi_sizestore((byte*) temp+4,next_filepos); + } + else + { + mi_int2store(temp+1,length-head_length); + mi_sizestore((byte*) temp+3,next_filepos); + } + } + } + else + { /* Block with empty info last */ + head_length=4+long_block; + extra_length= length- *reclength-head_length; + temp[0]= (uchar) (3+ *flag)+(uchar) long_block; /* 3,4 or 9,10 */ + if (long_block) + { + mi_int3store(temp+1,*reclength); + temp[4]= (uchar) (extra_length); + } + else + { + mi_int2store(temp+1,*reclength); + temp[3]= (uchar) (extra_length); + } + length= *reclength+head_length; /* Write only what is needed */ + } + DBUG_DUMP("header",(byte*) temp,head_length); + + /* Make a long block for one write */ + record_end= *record+length-head_length; + del_length=(res_length ? MI_DYN_DELETE_BLOCK_HEADER : 0); + bmove((byte*) (*record-head_length),(byte*) temp,head_length); + memcpy(temp,record_end,(size_t) (extra_length+del_length)); + bzero((byte*) record_end,extra_length); + + if (res_length) + { + /* Check first if we can join this block with the next one */ + MI_BLOCK_INFO del_block; + my_off_t next_block=filepos+length+extra_length+res_length; + + del_block.second_read=0; + if (next_block < info->state->data_file_length && + info->s->state.dellink != HA_OFFSET_ERROR) + { + if ((_mi_get_block_info(&del_block,info->dfile,next_block) + & BLOCK_DELETED) && + res_length + del_block.block_len < MI_DYN_MAX_BLOCK_LENGTH) + { + if (unlink_deleted_block(info,&del_block)) + goto err; + res_length+=del_block.block_len; + } + } + + /* Create a delete link of the last part of the block */ + pos=record_end+extra_length; + pos[0]= '\0'; + mi_int3store(pos+1,res_length); + mi_sizestore(pos+4,info->s->state.dellink); + bfill(pos+12,8,255); /* End link */ + next_delete_block=info->s->state.dellink; + info->s->state.dellink= filepos+length+extra_length; + info->state->del++; + info->state->empty+=res_length; + info->s->state.split++; + } + if (info->opt_flag & WRITE_CACHE_USED && + info->update & HA_STATE_WRITE_AT_END) + { + if (info->update & HA_STATE_EXTEND_BLOCK) + { + info->update&= ~HA_STATE_EXTEND_BLOCK; + if (my_block_write(&info->rec_cache,(byte*) *record-head_length, + length+extra_length+del_length,filepos)) + goto err; + } + else if (my_b_write(&info->rec_cache,(byte*) *record-head_length, + length+extra_length+del_length)) + goto err; + } + else + { + info->rec_cache.seek_not_done=1; + if (my_pwrite(info->dfile,(byte*) *record-head_length,length+extra_length+ + del_length,filepos,info->s->write_flag)) + goto err; + } + memcpy(record_end,temp,(size_t) (extra_length+del_length)); + *record=record_end; + *reclength-=(length-head_length); + *flag=6; + + if (del_length && next_delete_block != HA_OFFSET_ERROR) + { + /* link the next delete block to this */ + MI_BLOCK_INFO del_block; + del_block.second_read=0; + if (!(_mi_get_block_info(&del_block,info->dfile,next_delete_block) + & BLOCK_DELETED)) + { + my_errno=HA_ERR_WRONG_IN_RECORD; + goto err; + } + mi_sizestore(del_block.header+12,info->s->state.dellink); + if (my_pwrite(info->dfile,(char*) del_block.header+12,8, + next_delete_block+12, + MYF(MY_NABP))) + goto err; + } + + DBUG_RETURN(0); +err: + DBUG_PRINT("exit",("errno: %d",my_errno)); + DBUG_RETURN(1); +} /*_mi_write_part_record */ + + + /* update record from datafile */ + +static int update_dynamic_record(MI_INFO *info, my_off_t filepos, byte *record, + ulong reclength) +{ + int flag; + uint error; + ulong length; + MI_BLOCK_INFO block_info; + DBUG_ENTER("update_dynamic_record"); + + flag=block_info.second_read=0; + while (reclength > 0) + { + if (filepos != info->s->state.dellink) + { + block_info.next_filepos= HA_OFFSET_ERROR; + if ((error=_mi_get_block_info(&block_info,info->dfile,filepos)) + & (BLOCK_DELETED | BLOCK_ERROR | BLOCK_SYNC_ERROR | + BLOCK_FATAL_ERROR)) + { + DBUG_PRINT("error",("Got wrong block info")); + if (!(error & BLOCK_FATAL_ERROR)) + my_errno=HA_ERR_WRONG_IN_RECORD; + goto err; + } + length=(ulong) (block_info.filepos-filepos) + block_info.block_len; + if (length < reclength) + { + uint tmp=MY_ALIGN(reclength - length + 3 + + test(reclength >= 65520L),MI_DYN_ALIGN_SIZE); + /* Check if we can extend this block */ + if (block_info.filepos + block_info.block_len == + info->state->data_file_length && + info->state->data_file_length < + info->s->base.max_data_file_length-tmp) + { + /* extend file */ + DBUG_PRINT("info",("Extending file with %d bytes",tmp)); + if (info->nextpos == info->state->data_file_length) + info->nextpos+= tmp; + info->state->data_file_length+= tmp; + info->update|= HA_STATE_WRITE_AT_END | HA_STATE_EXTEND_BLOCK; + length+=tmp; + } + else + { + /* Check if next block is a deleted block */ + MI_BLOCK_INFO del_block; + del_block.second_read=0; + if (_mi_get_block_info(&del_block,info->dfile, + block_info.filepos + block_info.block_len) & + BLOCK_DELETED) + { + /* Use; Unlink it and extend the current block */ + DBUG_PRINT("info",("Extending current block")); + if (unlink_deleted_block(info,&del_block)) + goto err; + length+=del_block.block_len; + } + } + } + } + else + { + if (_mi_find_writepos(info,reclength,&filepos,&length)) + goto err; + } + if (_mi_write_part_record(info,filepos,length,block_info.next_filepos, + &record,&reclength,&flag)) + goto err; + if ((filepos=block_info.next_filepos) == HA_OFFSET_ERROR) + filepos=info->s->state.dellink; + } + + if (block_info.next_filepos != HA_OFFSET_ERROR) + if (delete_dynamic_record(info,block_info.next_filepos,1)) + goto err; + DBUG_RETURN(0); +err: + DBUG_RETURN(1); +} + + + /* Pack a record. Return new reclength */ + +uint _mi_rec_pack(MI_INFO *info, register byte *to, register const byte *from) +{ + uint length,new_length,flag,bit,i; + char *pos,*end,*startpos,*packpos; + enum en_fieldtype type; + reg3 MI_COLUMNDEF *rec; + MI_BLOB *blob; + DBUG_ENTER("_mi_rec_pack"); + + flag=0 ; bit=1; + startpos=packpos=to; to+= info->s->base.pack_bits; blob=info->blobs; + rec=info->s->rec; + + for (i=info->s->base.fields ; i-- > 0; from+= length,rec++) + { + length=(uint) rec->length; + if ((type = (enum en_fieldtype) rec->type) != FIELD_NORMAL) + { + if (type == FIELD_BLOB) + { + if (!blob->length) + flag|=bit; + else + { + char *temp_pos; + size_t tmp_length=length-mi_portable_sizeof_char_ptr; + memcpy((byte*) to,from,tmp_length); + memcpy_fixed(&temp_pos,from+tmp_length,sizeof(char*)); + memcpy(to+tmp_length,temp_pos,(size_t) blob->length); + to+=tmp_length+blob->length; + } + blob++; + } + else if (type == FIELD_SKIPP_ZERO) + { + if (memcmp((byte*) from,zero_string,length) == 0) + flag|=bit; + else + { + memcpy((byte*) to,from,(size_t) length); to+=length; + } + } + else if (type == FIELD_SKIPP_ENDSPACE || + type == FIELD_SKIPP_PRESPACE) + { + pos= (byte*) from; end= (byte*) from + length; + if (type == FIELD_SKIPP_ENDSPACE) + { /* Pack trailing spaces */ + while (end > from && *(end-1) == ' ') + end--; + } + else + { /* Pack pref-spaces */ + while (pos < end && *pos == ' ') + pos++; + } + new_length=(uint) (end-pos); + if (new_length +1 + test(rec->length > 255 && new_length > 127) + < length) + { + if (rec->length > 255 && new_length > 127) + { + to[0]=(char) ((new_length & 127)+128); + to[1]=(char) (new_length >> 7); + to+=2; + } + else + *to++= (char) new_length; + memcpy((byte*) to,pos,(size_t) new_length); to+=new_length; + flag|=bit; + } + else + { + memcpy(to,from,(size_t) length); to+=length; + } + } + else if (type == FIELD_VARCHAR) + { + uint tmp_length=uint2korr(from); + store_key_length_inc(to,tmp_length); + memcpy(to,from+2,tmp_length); + to+=tmp_length; + continue; + } + else + { + memcpy(to,from,(size_t) length); to+=length; + continue; /* Normal field */ + } + if ((bit= bit << 1) >= 256) + { + *packpos++ = (char) (uchar) flag; + bit=1; flag=0; + } + } + else + { + memcpy(to,from,(size_t) length); to+=length; + } + } + if (bit != 1) + *packpos= (char) (uchar) flag; + if (info->s->calc_checksum) + *to++=(char) info->checksum; + DBUG_PRINT("exit",("packed length: %d",(int) (to-startpos))); + DBUG_RETURN((uint) (to-startpos)); +} /* _mi_rec_pack */ + + + +/* +** Check if a record was correctly packed. Used only by isamchk +** Returns 0 if record is ok. +*/ + +my_bool _mi_rec_check(MI_INFO *info,const char *record) +{ + uint length,new_length,flag,bit,i; + char *pos,*end,*packpos,*to; + enum en_fieldtype type; + reg3 MI_COLUMNDEF *rec; + DBUG_ENTER("_mi_rec_check"); + + packpos=info->rec_buff; to= info->rec_buff+info->s->base.pack_bits; + rec=info->s->rec; + flag= *packpos; bit=1; + + for (i=info->s->base.fields ; i-- > 0; record+= length, rec++) + { + length=(uint) rec->length; + if ((type = (enum en_fieldtype) rec->type) != FIELD_NORMAL) + { + if (type == FIELD_BLOB) + { + uint blob_length= + _mi_calc_blob_length(length-mi_portable_sizeof_char_ptr,record); + if (!blob_length && !(flag & bit)) + goto err; + if (blob_length) + to+=length - mi_portable_sizeof_char_ptr+ blob_length; + } + else if (type == FIELD_SKIPP_ZERO) + { + if (memcmp((byte*) record,zero_string,length) == 0) + { + if (!(flag & bit)) + goto err; + } + else + to+=length; + } + else if (type == FIELD_SKIPP_ENDSPACE || + type == FIELD_SKIPP_PRESPACE) + { + pos= (byte*) record; end= (byte*) record + length; + if (type == FIELD_SKIPP_ENDSPACE) + { /* Pack trailing spaces */ + while (end > record && *(end-1) == ' ') + end--; + } + else + { /* Pack pre-spaces */ + while (pos < end && *pos == ' ') + pos++; + } + new_length=(uint) (end-pos); + if (new_length +1 + test(rec->length > 255 && new_length > 127) + < length) + { + if (!(flag & bit)) + goto err; + if (rec->length > 255 && new_length > 127) + { + if (to[0] != (char) ((new_length & 127)+128) || + to[1] != (char) (new_length >> 7)) + goto err; + to+=2; + } + else if (*to++ != (char) new_length) + goto err; + to+=new_length; + } + else + to+=length; + } + else if (type == FIELD_VARCHAR) + { + uint tmp_length=uint2korr(record); + to+=get_pack_length(tmp_length)+tmp_length; + continue; + } + else + { + to+=length; + continue; /* Normal field */ + } + if ((bit= bit << 1) >= 256) + { + flag= *++packpos; + bit=1; + } + } + else + { + to+=length; + } + } + if (info->packed_length != (uint) (to - info->rec_buff) + + test(info->s->calc_checksum) || + (bit != 1 && (flag & ~(bit - 1)))) + goto err; + if (info->s->calc_checksum) + { + if ((uchar) info->checksum != (uchar) *to) + { + DBUG_PRINT("error",("wrong checksum for row")); + goto err; + } + } + DBUG_RETURN(0); + + err: + DBUG_RETURN(1); +} + + + + /* Unpacks a record */ + /* Returns -1 and my_errno =HA_ERR_RECORD_DELETED if reclength isn't */ + /* right. Returns reclength (>0) if ok */ + +ulong _mi_rec_unpack(register MI_INFO *info, register byte *to, byte *from, + ulong found_length) +{ + uint flag,bit,length,rec_length,min_pack_length; + enum en_fieldtype type; + byte *from_end,*to_end,*packpos; + reg3 MI_COLUMNDEF *rec,*end_field; + DBUG_ENTER("_mi_rec_unpack"); + + to_end=to + info->s->base.reclength; + from_end=from+found_length; + flag= (uchar) *from; bit=1; packpos=from; + if (found_length < info->s->base.min_pack_length) + goto err; + from+= info->s->base.pack_bits; + min_pack_length=info->s->base.min_pack_length - info->s->base.pack_bits; + + for (rec=info->s->rec , end_field=rec+info->s->base.fields ; + rec < end_field ; to+= rec_length, rec++) + { + rec_length=rec->length; + if ((type = (enum en_fieldtype) rec->type) != FIELD_NORMAL && + (type != FIELD_CHECK)) + { + if (type == FIELD_VARCHAR) + { + get_key_length(length,from); + if (length > rec_length-2) + goto err; + int2store(to,length); + memcpy(to+2,from,length); + from+=length; + continue; + } + if (flag & bit) + { + if (type == FIELD_BLOB || type == FIELD_SKIPP_ZERO) + bzero((byte*) to,rec_length); + else if (type == FIELD_SKIPP_ENDSPACE || + type == FIELD_SKIPP_PRESPACE) + { + if (rec->length > 255 && *from & 128) + { + if (from + 1 >= from_end) + goto err; + length= (*from & 127)+ ((uint) (uchar) *(from+1) << 7); from+=2; + } + else + { + if (from == from_end) + goto err; + length= (uchar) *from++; + } + min_pack_length--; + if (length >= rec_length || + min_pack_length + length > (uint) (from_end - from)) + goto err; + if (type == FIELD_SKIPP_ENDSPACE) + { + memcpy(to,(byte*) from,(size_t) length); + bfill((byte*) to+length,rec_length-length,' '); + } + else + { + bfill((byte*) to,rec_length-length,' '); + memcpy(to+rec_length-length,(byte*) from,(size_t) length); + } + from+=length; + } + } + else if (type == FIELD_BLOB) + { + uint size_length=rec_length- mi_portable_sizeof_char_ptr; + ulong blob_length=_mi_calc_blob_length(size_length,from); + if ((ulong) (from_end-from) - size_length < blob_length || + min_pack_length > (uint) (from_end -(from+size_length+blob_length))) + goto err; + memcpy((byte*) to,(byte*) from,(size_t) size_length); + from+=size_length; + memcpy_fixed((byte*) to+size_length,(byte*) &from,sizeof(char*)); + from+=blob_length; + } + else + { + if (type == FIELD_SKIPP_ENDSPACE || type == FIELD_SKIPP_PRESPACE) + min_pack_length--; + if (min_pack_length + rec_length > (uint) (from_end - from)) + goto err; + memcpy(to,(byte*) from,(size_t) rec_length); from+=rec_length; + } + if ((bit= bit << 1) >= 256) + { + flag= (uchar) *++packpos; bit=1; + } + } + else + { + if (min_pack_length > (uint) (from_end - from)) + goto err; + min_pack_length-=rec_length; + memcpy(to,(byte*) from,(size_t) rec_length); from+=rec_length; + } + } + if (info->s->calc_checksum) + from++; + if (to == to_end && from == from_end && (bit == 1 || !(flag & ~(bit-1)))) + DBUG_RETURN((info->packed_length=found_length)); + err: + my_errno=HA_ERR_RECORD_DELETED; + DBUG_PRINT("error",("to_end: %lx -> %lx from_end: %lx -> %lx", + to,to_end,from,from_end)); + DBUG_DUMP("from",(byte*) info->rec_buff,info->s->base.min_pack_length); + DBUG_RETURN(MY_FILE_ERROR); +} /* _mi_rec_unpack */ + + + /* Calc length of blob. Update info in blobs->length */ + +ulong _my_calc_total_blob_length(MI_INFO *info, const byte *record) +{ + ulong length; + MI_BLOB *blob,*end; + + for (length=0, blob= info->blobs, end=blob+info->s->base.blobs ; + blob != end; + blob++) + { + blob->length=_mi_calc_blob_length(blob->pack_length,record + blob->offset); + length+=blob->length; + } + return length; +} + + +ulong _mi_calc_blob_length(uint length, const byte *pos) +{ + switch (length) { + case 1: + return (uint) (uchar) *pos; + case 2: + return (uint) uint2korr(pos); + case 3: + return uint3korr(pos); + case 4: + return uint4korr(pos); + default: + break; + } + return 0; /* Impossible */ +} + + +void _my_store_blob_length(byte *pos,uint pack_length,uint length) +{ + switch (pack_length) { + case 1: + *pos= (uchar) length; + break; + case 2: + int2store(pos,length); + break; + case 3: + int3store(pos,length); + break; + case 4: + int4store(pos,length); + default: + break; + } + return; +} + + + /* Read record from datafile */ + /* Returns 0 if ok, -1 if error */ + +int _mi_read_dynamic_record(MI_INFO *info, my_off_t filepos, byte *buf) +{ + int flag; + uint b_type,left_length; + byte *to; + MI_BLOCK_INFO block_info; + File file; + DBUG_ENTER("mi_read_dynamic_record"); + + if (filepos != HA_OFFSET_ERROR) + { + LINT_INIT(to); + LINT_INIT(left_length); + file=info->dfile; + block_info.next_filepos=filepos; /* for easyer loop */ + flag=block_info.second_read=0; + do + { + if (info->opt_flag & WRITE_CACHE_USED && + info->rec_cache.pos_in_file <= block_info.next_filepos && + flush_io_cache(&info->rec_cache)) + goto err; + info->rec_cache.seek_not_done=1; + if ((b_type=_mi_get_block_info(&block_info,file, + block_info.next_filepos)) + & (BLOCK_DELETED | BLOCK_ERROR | BLOCK_SYNC_ERROR | + BLOCK_FATAL_ERROR)) + { + if (b_type & (BLOCK_SYNC_ERROR | BLOCK_DELETED)) + my_errno=HA_ERR_RECORD_DELETED; + goto err; + } + if (flag == 0) /* First block */ + { + flag=1; + if (block_info.rec_len > (uint) info->s->base.max_pack_length) + goto panic; + if (info->s->base.blobs) + { + if (!(to=mi_fix_rec_buff_for_blob(info,block_info.rec_len))) + goto err; + } + else + to= info->rec_buff; + left_length=block_info.rec_len; + } + if (left_length < block_info.data_len || ! block_info.data_len) + goto panic; /* Wrong linked record */ + if (my_pread(file,(byte*) to,block_info.data_len,block_info.filepos, + MYF(MY_NABP))) + goto panic; + left_length-=block_info.data_len; + to+=block_info.data_len; + } while (left_length); + + info->update|= HA_STATE_AKTIV; /* We have a aktive record */ + VOID(_mi_writeinfo(info,0)); + DBUG_RETURN(_mi_rec_unpack(info,buf,info->rec_buff,block_info.rec_len) != + MY_FILE_ERROR ? 0 : -1); + } + VOID(_mi_writeinfo(info,0)); + DBUG_RETURN(-1); /* Wrong data to read */ + +panic: + my_errno=HA_ERR_WRONG_IN_RECORD; +err: + VOID(_mi_writeinfo(info,0)); + DBUG_RETURN(-1); +} + + +byte *mi_fix_rec_buff_for_blob(MI_INFO *info, ulong length) +{ + uint extra; + if (! info->rec_buff || length > info->alloced_rec_buff_length) + { + byte *newptr; + extra=ALIGN_SIZE(MI_MAX_DYN_BLOCK_HEADER)+MI_SPLIT_LENGTH+ + MI_DYN_DELETE_BLOCK_HEADER; + if (!(newptr=(byte*) my_realloc((gptr) info->rec_alloc,length+extra, + MYF(MY_ALLOW_ZERO_PTR)))) + return newptr; + info->rec_alloc=newptr; + info->rec_buff=newptr+ALIGN_SIZE(MI_DYN_DELETE_BLOCK_HEADER); + info->alloced_rec_buff_length=length; + } + return info->rec_buff; +} + + + /* compare unique constraint between stored rows */ + +int _mi_cmp_dynamic_unique(MI_INFO *info, MI_UNIQUEDEF *def, + const byte *record, my_off_t pos) +{ + byte *rec_buff,*rec_alloc,*old_record; + uint alloced_rec_buff_length; + int error; + DBUG_ENTER("_mi_cmp_dynamic_unique"); + + if (!(old_record=my_alloca(info->s->base.reclength))) + DBUG_RETURN(1); + + /* Don't let the compare destroy blobs that may be in use */ + rec_buff=info->rec_buff; + rec_alloc=info->rec_alloc; + alloced_rec_buff_length=info->alloced_rec_buff_length; + if (info->s->base.blobs) + { + info->rec_buff=0; + info->rec_alloc=0; + info->alloced_rec_buff_length=0; + } + error=_mi_read_dynamic_record(info,pos,old_record); + if (!error) + error=mi_unique_comp(def, record, old_record, def->null_are_equal); + if (info->s->base.blobs) + { + my_free(info->rec_alloc,MYF(MY_ALLOW_ZERO_PTR)); + info->rec_buff=rec_buff; + info->rec_alloc=rec_alloc; + info->alloced_rec_buff_length=alloced_rec_buff_length; + } + my_afree(old_record); + DBUG_RETURN(error); +} + + + /* Compare of record one disk with packed record in memory */ + +int _mi_cmp_dynamic_record(register MI_INFO *info, register const byte *record) +{ + uint flag,reclength,b_type; + my_off_t filepos; + byte *buffer; + MI_BLOCK_INFO block_info; + DBUG_ENTER("_mi_cmp_dynamic_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) + { + info->update&= ~(HA_STATE_WRITE_AT_END | HA_STATE_EXTEND_BLOCK); + if (flush_io_cache(&info->rec_cache)) + DBUG_RETURN(-1); + } + info->rec_cache.seek_not_done=1; + + /* If nobody have touched the database we don't have to test rec */ + + buffer=info->rec_buff; + if ((info->opt_flag & READ_CHECK_USED)) + { /* If check isn't disabled */ + if (info->s->base.blobs) + { + if (!(buffer=(byte*) my_alloca(info->s->base.pack_reclength+ + _my_calc_total_blob_length(info,record)))) + DBUG_RETURN(-1); + } + reclength=_mi_rec_pack(info,buffer,record); + record= buffer; + + filepos=info->lastpos; + flag=block_info.second_read=0; + block_info.next_filepos=filepos; + while (reclength > 0) + { + if ((b_type=_mi_get_block_info(&block_info,info->dfile, + block_info.next_filepos)) + & (BLOCK_DELETED | BLOCK_ERROR | BLOCK_SYNC_ERROR | + BLOCK_FATAL_ERROR)) + { + if (b_type & (BLOCK_SYNC_ERROR | BLOCK_DELETED)) + my_errno=HA_ERR_RECORD_CHANGED; + goto err; + } + if (flag == 0) /* First block */ + { + flag=1; + if (reclength != block_info.rec_len) + { + my_errno=HA_ERR_RECORD_CHANGED; + goto err; + } + } else if (reclength < block_info.data_len) + { + my_errno=HA_ERR_WRONG_IN_RECORD; + goto err; + } + reclength-=block_info.data_len; + if (_mi_cmp_buffer(info->dfile,record,block_info.filepos, + block_info.data_len)) + { + my_errno=HA_ERR_RECORD_CHANGED; + goto err; + } + flag=1; + record+=block_info.data_len; + } + } + my_errno=0; + err: + if (buffer != info->rec_buff) + my_afree((gptr) buffer); + DBUG_RETURN(my_errno); +} + + + /* Compare file to buffert */ + +static int _mi_cmp_buffer(File file, const byte *buff, my_off_t filepos, + uint length) +{ + uint next_length; + char temp_buff[IO_SIZE*2]; + DBUG_ENTER("_mi_cmp_buffer"); + + VOID(my_seek(file,filepos,MY_SEEK_SET,MYF(0))); + next_length= IO_SIZE*2 - (uint) (filepos & (IO_SIZE-1)); + + while (length > IO_SIZE*2) + { + if (my_read(file,temp_buff,next_length,MYF(MY_NABP))) + goto err; + if (memcmp((byte*) buff,temp_buff,IO_SIZE)) + DBUG_RETURN(1); + buff+=next_length; + length-= next_length; + next_length=IO_SIZE*2; + } + if (my_read(file,temp_buff,length,MYF(MY_NABP))) + goto err; + DBUG_RETURN(memcmp((byte*) buff,temp_buff,length)); +err: + DBUG_RETURN(1); +} + + +int _mi_read_rnd_dynamic_record(MI_INFO *info, byte *buf, + register my_off_t filepos, + my_bool skipp_deleted_blocks) +{ + int flag,info_read,save_errno; + uint left_len,b_type; + byte *to; + MI_BLOCK_INFO block_info; + MYISAM_SHARE *share=info->s; + DBUG_ENTER("_mi_read_rnd_dynamic_record"); + + info_read=0; + LINT_INIT(to); + + if (info->lock_type == F_UNLCK) + { +#ifndef UNSAFE_LOCKING + if (share->r_locks == 0 && share->w_locks == 0) + { + if (my_lock(share->kfile,F_RDLCK,0L,F_TO_EOF, + MYF(MY_SEEK_NOT_DONE) | info->lock_wait)) + DBUG_RETURN(my_errno); + } +#else + info->tmp_lock_type=F_RDLCK; +#endif + } + else + info_read=1; /* memory-keyinfoblock is ok */ + + flag=block_info.second_read=0; + left_len=1; + do + { + if (filepos >= info->state->data_file_length) + { + if (!info_read) + { /* Check if changed */ + info_read=1; + info->rec_cache.seek_not_done=1; + if (mi_state_info_read_dsk(share->kfile,&share->state,1)) + goto panic; + } + if (filepos >= info->state->data_file_length) + { + my_errno= HA_ERR_END_OF_FILE; + goto err; + } + } + if (info->opt_flag & READ_CACHE_USED) + { + if (_mi_read_cache(&info->rec_cache,(byte*) block_info.header,filepos, + sizeof(block_info.header), + test(!flag && skipp_deleted_blocks) | 2)) + goto panic; + b_type=_mi_get_block_info(&block_info,-1,filepos); + } + else + { + if (info->opt_flag & WRITE_CACHE_USED && + info->rec_cache.pos_in_file <= filepos && + flush_io_cache(&info->rec_cache)) + DBUG_RETURN(my_errno); + info->rec_cache.seek_not_done=1; + b_type=_mi_get_block_info(&block_info,info->dfile,filepos); + } + + if (b_type & (BLOCK_DELETED | BLOCK_ERROR | BLOCK_SYNC_ERROR | + BLOCK_FATAL_ERROR)) + { + if ((b_type & (BLOCK_DELETED | BLOCK_SYNC_ERROR)) + && skipp_deleted_blocks) + { + filepos=block_info.filepos+block_info.block_len; + block_info.second_read=0; + continue; /* Search after next_record */ + } + if (b_type & (BLOCK_DELETED | BLOCK_SYNC_ERROR)) + { + my_errno=HA_ERR_RECORD_DELETED; + info->lastpos=block_info.filepos; + info->nextpos=block_info.filepos+block_info.block_len; + } + goto err; + } + if (flag == 0) /* First block */ + { + if (block_info.rec_len > (uint) share->base.max_pack_length) + goto panic; + info->lastpos=filepos; + if (share->base.blobs) + { + if (!(to=mi_fix_rec_buff_for_blob(info,block_info.rec_len))) + goto err; + } + else + to= info->rec_buff; + left_len=block_info.rec_len; + } + if (left_len < block_info.data_len) + goto panic; /* Wrong linked record */ + + /* copy information that is already read */ + { + uint offset=(uint) (block_info.filepos - filepos); + uint tmp_length= (sizeof(block_info.header) - offset); + filepos=block_info.filepos; + + if (tmp_length > block_info.data_len) + tmp_length= block_info.data_len; + if (tmp_length) + { + memcpy((byte*) to, block_info.header+offset,tmp_length); + block_info.data_len-=tmp_length; + left_len-=tmp_length; + to+=tmp_length; + filepos+=tmp_length; + } + } + /* read rest of record from file */ + if (block_info.data_len) + { + if (info->opt_flag & READ_CACHE_USED) + { + if (_mi_read_cache(&info->rec_cache,(byte*) to,filepos, + block_info.data_len, + test(!flag && skipp_deleted_blocks))) + goto panic; + } + else + { + /* VOID(my_seek(info->dfile,filepos,MY_SEEK_SET,MYF(0))); */ + if (my_read(info->dfile,(byte*) to,block_info.data_len,MYF(MY_NABP))) + { + if (my_errno == -1) + my_errno= HA_ERR_WRONG_IN_RECORD; /* Unexpected end of file */ + goto err; + } + } + } + if (flag++ == 0) + { + info->nextpos=block_info.filepos+block_info.block_len; + skipp_deleted_blocks=0; + } + left_len-=block_info.data_len; + to+=block_info.data_len; + filepos=block_info.next_filepos; + } while (left_len); + + info->update|= HA_STATE_AKTIV | HA_STATE_KEY_CHANGED; + if (share->r_locks == 0 && share->w_locks == 0) + VOID(_mi_writeinfo(info,0)); + if (_mi_rec_unpack(info,buf,info->rec_buff,block_info.rec_len) != + MY_FILE_ERROR) + DBUG_RETURN(0); + DBUG_RETURN(my_errno); /* Wrong record */ + +panic: + my_errno=HA_ERR_WRONG_IN_RECORD; /* Something is fatal wrong */ +err: + save_errno=my_errno; + VOID(_mi_writeinfo(info,0)); + DBUG_RETURN(my_errno=save_errno); +} + + + /* Read and process header from a dynamic-record-file */ + +uint _mi_get_block_info(MI_BLOCK_INFO *info, File file, my_off_t filepos) +{ + uint return_val=0; + uchar *header=info->header; + + if (file >= 0) + { + VOID(my_seek(file,filepos,MY_SEEK_SET,MYF(0))); + if (my_read(file,(char*) header,sizeof(info->header),MYF(0)) != + sizeof(info->header)) + { + my_errno=HA_ERR_WRONG_IN_RECORD; + return BLOCK_FATAL_ERROR; + } + } + DBUG_DUMP("header",(byte*) header,MI_BLOCK_INFO_HEADER_LENGTH); + if (info->second_read) + { + if (info->header[0] <= 6) + return_val=BLOCK_SYNC_ERROR; + } + else + { + if (info->header[0] > 6) + return_val=BLOCK_SYNC_ERROR; + } + info->next_filepos= HA_OFFSET_ERROR; /* Dummy ifall no next block */ + + switch (info->header[0]) { + case 0: + if ((info->block_len=(uint) mi_uint3korr(header+1)) < + MI_MIN_BLOCK_LENGTH || + (info->block_len & (MI_DYN_ALIGN_SIZE -1))) + { + my_errno=HA_ERR_WRONG_IN_RECORD; + return BLOCK_ERROR; + } + info->filepos=filepos; + info->next_filepos=mi_sizekorr(header+4); + info->prev_filepos=mi_sizekorr(header+12); +#if SIZEOF_OFF_T == 4 + if ((mi_uint4korr(header+4) != 0 && + (mi_uint4korr(header+4) != (ulong) ~0 || + info->next_filepos != (ulong) ~0)) || + (mi_uint4korr(header+12) != 0 && + (mi_uint4korr(header+12) != (ulong) ~0 || + info->prev_filepos != (ulong) ~0))) + return BLOCK_FATAL_ERROR; +#endif + return return_val | BLOCK_DELETED; /* Deleted block */ + + case 1: + info->rec_len=info->data_len=info->block_len=mi_uint2korr(header+1); + info->filepos=filepos+3; + return return_val | BLOCK_FIRST | BLOCK_LAST; + case 2: + info->rec_len=info->data_len=info->block_len=mi_uint3korr(header+1); + info->filepos=filepos+4; + return return_val | BLOCK_FIRST | BLOCK_LAST; + + case 3: + info->rec_len=info->data_len=mi_uint2korr(header+1); + info->block_len=info->rec_len+ (uint) header[3]; + info->filepos=filepos+4; + return return_val | BLOCK_FIRST | BLOCK_LAST; + case 4: + info->rec_len=info->data_len=mi_uint3korr(header+1); + info->block_len=info->rec_len+ (uint) header[4]; + info->filepos=filepos+5; + return return_val | BLOCK_FIRST | BLOCK_LAST; + + case 5: + info->rec_len=mi_uint2korr(header+1); + info->block_len=info->data_len=mi_uint2korr(header+3); + info->next_filepos=mi_sizekorr(header+5); + info->second_read=1; + info->filepos=filepos+13; + return return_val | BLOCK_FIRST; + case 6: + info->rec_len=mi_uint3korr(header+1); + info->block_len=info->data_len=mi_uint3korr(header+4); + info->next_filepos=mi_sizekorr(header+7); + info->second_read=1; + info->filepos=filepos+15; + return return_val | BLOCK_FIRST; + + /* The following blocks are identical to 1-6 without rec_len */ + case 7: + info->data_len=info->block_len=mi_uint2korr(header+1); + info->filepos=filepos+3; + return return_val | BLOCK_LAST; + case 8: + info->data_len=info->block_len=mi_uint3korr(header+1); + info->filepos=filepos+4; + return return_val | BLOCK_LAST; + + case 9: + info->data_len=mi_uint2korr(header+1); + info->block_len=info->data_len+ (uint) header[3]; + info->filepos=filepos+4; + return return_val | BLOCK_LAST; + case 10: + info->data_len=mi_uint3korr(header+1); + info->block_len=info->data_len+ (uint) header[4]; + info->filepos=filepos+5; + return return_val | BLOCK_LAST; + + case 11: + info->data_len=info->block_len=mi_uint2korr(header+1); + info->next_filepos=mi_sizekorr(header+3); + info->second_read=1; + info->filepos=filepos+11; + return return_val; + case 12: + info->data_len=info->block_len=mi_uint3korr(header+1); + info->next_filepos=mi_sizekorr(header+4); + info->second_read=1; + info->filepos=filepos+12; + return return_val; + default: + my_errno=HA_ERR_WRONG_IN_RECORD; /* Garbage */ + return BLOCK_ERROR; + } +} |