/* 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 A row may be stored in one or more linked blocks. The block size is between MI_MIN_BLOCK_LENGTH and MI_MAX_BLOCK_LENGTH. Each block is aligned on MI_DYN_ALIGN_SIZE. The reson for the max block size is to not have too many different types of blocks. For the differnet block types, look at _mi_get_block_info() */ #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,reclength2,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); #ifdef NOT_USED /* We now support big rows */ if (reclength > MI_DYN_MAX_ROW_LENGTH) { my_errno=HA_ERR_TO_BIG_ROW; return -1; } #endif if (!(rec_buff=(byte*) my_alloca(reclength))) { my_errno=ENOMEM; return(-1); } reclength2= _mi_rec_pack(info,rec_buff+ALIGN_SIZE(MI_MAX_DYN_BLOCK_HEADER), record); DBUG_PRINT("info",("reclength: %lu reclength2: %lu", reclength, reclength2)); DBUG_ASSERT(reclength2 <= reclength); error=write_dynamic_record(info,rec_buff+ALIGN_SIZE(MI_MAX_DYN_BLOCK_HEADER), reclength2); 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); #ifdef NOT_USED /* We now support big rows */ if (reclength > MI_DYN_MAX_ROW_LENGTH) { my_errno=HA_ERR_TO_BIG_ROW; return -1; } #endif 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; do { 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; } while (reclength); 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; ulong tmp; 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 ((tmp=reclength+3 + test(reclength >= (65520-3))) < info->s->base.min_block_length) tmp= info->s->base.min_block_length; else tmp= ((tmp+MI_DYN_ALIGN_SIZE-1) & (~ (ulong) (MI_DYN_ALIGN_SIZE-1))); if (info->state->data_file_length > (info->s->base.max_data_file_length - tmp)) { my_errno=HA_ERR_RECORD_FILE_FULL; DBUG_RETURN(-1); } if (tmp > MI_MAX_BLOCK_LENGTH) tmp=MI_MAX_BLOCK_LENGTH; *length= tmp; info->state->data_file_length+= tmp; info->s->state.split++; info->update|=HA_STATE_WRITE_AT_END; } DBUG_RETURN(0); } /* _mi_find_writepos */ /* Unlink a deleted block from the deleted list. This block will be combined with the preceding or next block to form a big block. */ 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; /* Unlink block from the previous block */ 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); /* Unlink block from next block */ 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); } } /* We now have one less deleted block */ info->state->del--; info->state->empty-= block_info->block_len; info->s->state.split--; /* If this was a block that we where accessing through table scan (mi_rrnd() or mi_scan(), then ensure that we skip over this block when doing next mi_rrnd() or mi_scan(). */ if (info->nextpos == block_info->filepos) info->nextpos+=block_info->block_len; DBUG_RETURN(0); } /* Add a backward link to delete block SYNOPSIS update_backward_delete_link() info MyISAM handler delete_block Position to delete block to update. If this is 'HA_OFFSET_ERROR', nothing will be done filepos Position to block that 'delete_block' should point to RETURN 0 ok 1 error. In this case my_error is set. */ static int update_backward_delete_link(MI_INFO *info, my_off_t delete_block, my_off_t filepos) { MI_BLOCK_INFO block_info; DBUG_ENTER("update_backward_delete_link"); if (delete_block != HA_OFFSET_ERROR) { block_info.second_read=0; if (_mi_get_block_info(&block_info,info->dfile,delete_block) & BLOCK_DELETED) { char buff[8]; mi_sizestore(buff,filepos); if (my_pwrite(info->dfile,buff, 8, delete_block+12, MYF(MY_NABP))) DBUG_RETURN(1); /* Error on write */ } else { my_errno=HA_ERR_WRONG_IN_RECORD; DBUG_RETURN(1); /* Wrong delete link */ } } 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; my_bool remove_next_block; DBUG_ENTER("delete_dynamic_record"); /* First add a link from the last block to the new one */ error= update_backward_delete_link(info, info->s->state.dellink, filepos); 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 deleted block directly after this one */ 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 */ { if (*reclength > MI_MAX_BLOCK_LENGTH) { head_length= 16; temp[0]=13; mi_int4store(temp+1,*reclength); mi_int3store(temp+5,length-head_length); mi_sizestore((byte*) temp+8,next_filepos); } else { 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) { /* link the next delete block to this */ if (update_backward_delete_link(info, next_delete_block, info->s->state.dellink)) 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); /* Don't create a block bigger than MI_MAX_BLOCK_LENGTH */ tmp= min(length+tmp, MI_MAX_BLOCK_LENGTH)-length; /* 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 if (length < MI_MAX_BLOCK_LENGTH - MI_MIN_BLOCK_LENGTH) { /* Check if next block is a deleted block Above we have MI_MIN_BLOCK_LENGTH to avoid the problem where the next block is so small it can't be splited which could casue problems */ 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; if ((length+=del_block.block_len) > MI_MAX_BLOCK_LENGTH) { /* New block was too big, link overflow part back to delete list */ my_off_t next_pos; ulong rest_length= length-MI_MAX_BLOCK_LENGTH; set_if_bigger(rest_length, MI_MIN_BLOCK_LENGTH); next_pos= del_block.filepos+ del_block.block_len - rest_length; if (update_backward_delete_link(info, info->s->state.dellink, next_pos)) DBUG_RETURN(1); /* create delete link for data that didn't fit into the page */ del_block.header[0]=0; mi_int3store(del_block.header+1, rest_length); mi_sizestore(del_block.header+4,info->s->state.dellink); bfill(del_block.header+12,8,255); if (my_pwrite(info->dfile,(byte*) del_block.header,20, next_pos, MYF(MY_NABP))) DBUG_RETURN(1); info->s->state.dellink= next_pos; info->s->state.split++; info->state->del++; info->state->empty+= rest_length; length-= rest_length; } } } } } 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) { /* Start writing data on deleted blocks */ 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_SKIP_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_SKIP_ENDSPACE || type == FIELD_SKIP_PRESPACE) { pos= (byte*) from; end= (byte*) from + length; if (type == FIELD_SKIP_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 myisamchk Returns 0 if record is ok. */ my_bool _mi_rec_check(MI_INFO *info,const char *record, byte *rec_buff, ulong packed_length, my_bool with_checksum) { 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=rec_buff; to= 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_SKIP_ZERO) { if (memcmp((byte*) record,zero_string,length) == 0) { if (!(flag & bit)) goto err; } else to+=length; } else if (type == FIELD_SKIP_ENDSPACE || type == FIELD_SKIP_PRESPACE) { pos= (byte*) record; end= (byte*) record + length; if (type == FIELD_SKIP_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 (packed_length != (uint) (to - rec_buff) + test(info->s->calc_checksum) || (bit != 1 && (flag & ~(bit - 1)))) goto err; if (with_checksum && ((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_SKIP_ZERO) bzero((byte*) to,rec_length); else if (type == FIELD_SKIP_ENDSPACE || type == FIELD_SKIP_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_SKIP_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_SKIP_ENDSPACE || type == FIELD_SKIP_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(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; /* A corrupted table can have wrong pointers. (Bug# 19835) */ if (block_info.next_filepos == HA_OFFSET_ERROR) goto panic; 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_alloc_rec_buff(info, block_info.rec_len, &info->rec_buff))) 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 */ fast_mi_writeinfo(info); DBUG_RETURN(_mi_rec_unpack(info,buf,info->rec_buff,block_info.rec_len) != MY_FILE_ERROR ? 0 : -1); } fast_mi_writeinfo(info); DBUG_RETURN(-1); /* Wrong data to read */ panic: my_errno=HA_ERR_WRONG_IN_RECORD; err: VOID(_mi_writeinfo(info,0)); DBUG_RETURN(-1); } /* 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,*old_record; 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; if (info->s->base.blobs) info->rec_buff=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(mi_get_rec_buff_ptr(info, info->rec_buff), MYF(MY_ALLOW_ZERO_PTR)); info->rec_buff=rec_buff; } 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"); next_length= IO_SIZE*2 - (uint) (filepos & (IO_SIZE-1)); while (length > IO_SIZE*2) { if (my_pread(file,temp_buff,next_length,filepos, MYF(MY_NABP)) || memcmp((byte*) buff,temp_buff,next_length)) goto err; filepos+=next_length; buff+=next_length; length-= next_length; next_length=IO_SIZE*2; } if (my_pread(file,temp_buff,length,filepos,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 skip_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->tot_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), (!flag && skip_deleted_blocks ? READING_NEXT : 0) | READING_HEADER)) 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)) && skip_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_alloc_rec_buff(info, block_info.rec_len, &info->rec_buff))) 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, (!flag && skip_deleted_blocks) ? READING_NEXT :0)) 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; skip_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; fast_mi_writeinfo(info); 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)) goto err; } DBUG_DUMP("header",(byte*) header,MI_BLOCK_INFO_HEADER_LENGTH); if (info->second_read) { if (info->header[0] <= 6 || info->header[0] == 13) return_val=BLOCK_SYNC_ERROR; } else { if (info->header[0] > 6 && info->header[0] != 13) return_val=BLOCK_SYNC_ERROR; } info->next_filepos= HA_OFFSET_ERROR; /* Dummy if 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))) goto err; 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))) goto err; #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 13: info->rec_len=mi_uint4korr(header+1); info->block_len=info->data_len=mi_uint3korr(header+5); info->next_filepos=mi_sizekorr(header+8); info->second_read=1; info->filepos=filepos+16; return return_val | BLOCK_FIRST; 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; } err: my_errno=HA_ERR_WRONG_IN_RECORD; /* Garbage */ return BLOCK_ERROR; }