diff options
Diffstat (limited to 'storage/heap/hp_hash.c')
| -rw-r--r-- | storage/heap/hp_hash.c | 984 |
1 files changed, 984 insertions, 0 deletions
diff --git a/storage/heap/hp_hash.c b/storage/heap/hp_hash.c new file mode 100644 index 00000000000..3121ef71fb0 --- /dev/null +++ b/storage/heap/hp_hash.c @@ -0,0 +1,984 @@ +/* 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 */ + +/* The hash functions used for saveing keys */ + +#include "heapdef.h" +#include <m_ctype.h> + + + +/* + Find out how many rows there is in the given range + + SYNOPSIS + hp_rb_records_in_range() + info HEAP handler + inx Index to use + min_key Min key. Is = 0 if no min range + max_key Max key. Is = 0 if no max range + + NOTES + min_key.flag can have one of the following values: + HA_READ_KEY_EXACT Include the key in the range + HA_READ_AFTER_KEY Don't include key in range + + max_key.flag can have one of the following values: + HA_READ_BEFORE_KEY Don't include key in range + HA_READ_AFTER_KEY Include all 'end_key' values in the range + + RETURN + HA_POS_ERROR Something is wrong with the index tree. + 0 There is no matching keys in the given range + number > 0 There is approximately 'number' matching rows in + the range. +*/ + +ha_rows hp_rb_records_in_range(HP_INFO *info, int inx, key_range *min_key, + key_range *max_key) +{ + ha_rows start_pos, end_pos; + HP_KEYDEF *keyinfo= info->s->keydef + inx; + TREE *rb_tree = &keyinfo->rb_tree; + heap_rb_param custom_arg; + DBUG_ENTER("hp_rb_records_in_range"); + + info->lastinx= inx; + custom_arg.keyseg= keyinfo->seg; + custom_arg.search_flag= SEARCH_FIND | SEARCH_SAME; + if (min_key) + { + custom_arg.key_length= hp_rb_pack_key(keyinfo, (uchar*) info->recbuf, + (uchar*) min_key->key, + min_key->length); + start_pos= tree_record_pos(rb_tree, info->recbuf, min_key->flag, + &custom_arg); + } + else + { + start_pos= 0; + } + + if (max_key) + { + custom_arg.key_length= hp_rb_pack_key(keyinfo, (uchar*) info->recbuf, + (uchar*) max_key->key, + max_key->length); + end_pos= tree_record_pos(rb_tree, info->recbuf, max_key->flag, + &custom_arg); + } + else + { + end_pos= rb_tree->elements_in_tree + (ha_rows)1; + } + + DBUG_PRINT("info",("start_pos: %lu end_pos: %lu", (ulong) start_pos, + (ulong) end_pos)); + if (start_pos == HA_POS_ERROR || end_pos == HA_POS_ERROR) + DBUG_RETURN(HA_POS_ERROR); + DBUG_RETURN(end_pos < start_pos ? (ha_rows) 0 : + (end_pos == start_pos ? (ha_rows) 1 : end_pos - start_pos)); +} + + + /* Search after a record based on a key */ + /* Sets info->current_ptr to found record */ + /* next_flag: Search=0, next=1, prev =2, same =3 */ + +byte *hp_search(HP_INFO *info, HP_KEYDEF *keyinfo, const byte *key, + uint nextflag) +{ + reg1 HASH_INFO *pos,*prev_ptr; + int flag; + uint old_nextflag; + HP_SHARE *share=info->s; + DBUG_ENTER("hp_search"); + old_nextflag=nextflag; + flag=1; + prev_ptr=0; + + if (share->records) + { + pos=hp_find_hash(&keyinfo->block, hp_mask(hp_hashnr(keyinfo, key), + share->blength, share->records)); + do + { + if (!hp_key_cmp(keyinfo, pos->ptr_to_rec, key)) + { + switch (nextflag) { + case 0: /* Search after key */ + DBUG_PRINT("exit",("found key at %d",pos->ptr_to_rec)); + info->current_hash_ptr=pos; + DBUG_RETURN(info->current_ptr= pos->ptr_to_rec); + case 1: /* Search next */ + if (pos->ptr_to_rec == info->current_ptr) + nextflag=0; + break; + case 2: /* Search previous */ + if (pos->ptr_to_rec == info->current_ptr) + { + my_errno=HA_ERR_KEY_NOT_FOUND; /* If gpos == 0 */ + info->current_hash_ptr=prev_ptr; + DBUG_RETURN(info->current_ptr=prev_ptr ? prev_ptr->ptr_to_rec : 0); + } + prev_ptr=pos; /* Prev. record found */ + break; + case 3: /* Search same */ + if (pos->ptr_to_rec == info->current_ptr) + { + info->current_hash_ptr=pos; + DBUG_RETURN(info->current_ptr); + } + } + } + if (flag) + { + flag=0; /* Reset flag */ + if (hp_find_hash(&keyinfo->block, + hp_mask(hp_rec_hashnr(keyinfo, pos->ptr_to_rec), + share->blength, share->records)) != pos) + break; /* Wrong link */ + } + } + while ((pos=pos->next_key)); + } + my_errno=HA_ERR_KEY_NOT_FOUND; + if (nextflag == 2 && ! info->current_ptr) + { + /* Do a previous from end */ + info->current_hash_ptr=prev_ptr; + DBUG_RETURN(info->current_ptr=prev_ptr ? prev_ptr->ptr_to_rec : 0); + } + + if (old_nextflag && nextflag) + my_errno=HA_ERR_RECORD_CHANGED; /* Didn't find old record */ + DBUG_PRINT("exit",("Error: %d",my_errno)); + info->current_hash_ptr=0; + DBUG_RETURN((info->current_ptr= 0)); +} + + +/* + Search next after last read; Assumes that the table hasn't changed + since last read ! +*/ + +byte *hp_search_next(HP_INFO *info, HP_KEYDEF *keyinfo, const byte *key, + HASH_INFO *pos) +{ + DBUG_ENTER("hp_search_next"); + + while ((pos= pos->next_key)) + { + if (! hp_key_cmp(keyinfo, pos->ptr_to_rec, key)) + { + info->current_hash_ptr=pos; + DBUG_RETURN (info->current_ptr= pos->ptr_to_rec); + } + } + my_errno=HA_ERR_KEY_NOT_FOUND; + DBUG_PRINT("exit",("Error: %d",my_errno)); + info->current_hash_ptr=0; + DBUG_RETURN ((info->current_ptr= 0)); +} + + +/* + Calculate position number for hash value. + SYNOPSIS + hp_mask() + hashnr Hash value + buffmax Value such that + 2^(n-1) < maxlength <= 2^n = buffmax + maxlength + + RETURN + Array index, in [0..maxlength) +*/ + +ulong hp_mask(ulong hashnr, ulong buffmax, ulong maxlength) +{ + if ((hashnr & (buffmax-1)) < maxlength) return (hashnr & (buffmax-1)); + return (hashnr & ((buffmax >> 1) -1)); +} + + +/* + Change + next_link -> ... -> X -> pos + to + next_link -> ... -> X -> newlink +*/ + +void hp_movelink(HASH_INFO *pos, HASH_INFO *next_link, HASH_INFO *newlink) +{ + HASH_INFO *old_link; + do + { + old_link=next_link; + } + while ((next_link=next_link->next_key) != pos); + old_link->next_key=newlink; + return; +} + +#ifndef NEW_HASH_FUNCTION + + /* Calc hashvalue for a key */ + +ulong hp_hashnr(register HP_KEYDEF *keydef, register const byte *key) +{ + /*register*/ + ulong nr=1, nr2=4; + HA_KEYSEG *seg,*endseg; + + for (seg=keydef->seg,endseg=seg+keydef->keysegs ; seg < endseg ; seg++) + { + uchar *pos=(uchar*) key; + key+=seg->length; + if (seg->null_bit) + { + key++; /* Skip null byte */ + if (*pos) /* Found null */ + { + nr^= (nr << 1) | 1; + continue; + } + pos++; + } + if (seg->type == HA_KEYTYPE_TEXT) + { + CHARSET_INFO *cs= seg->charset; + uint length= seg->length; + if (cs->mbmaxlen > 1) + { + uint char_length; + char_length= my_charpos(cs, pos, pos + length, length/cs->mbmaxlen); + set_if_smaller(length, char_length); + } + cs->coll->hash_sort(cs, pos, length, &nr, &nr2); + } + else if (seg->type == HA_KEYTYPE_VARTEXT1) /* Any VARCHAR segments */ + { + CHARSET_INFO *cs= seg->charset; + uint pack_length= 2; /* Key packing is constant */ + uint length= uint2korr(pos); + if (cs->mbmaxlen > 1) + { + uint char_length; + char_length= my_charpos(cs, pos +pack_length, + pos +pack_length + length, + seg->length/cs->mbmaxlen); + set_if_smaller(length, char_length); + } + cs->coll->hash_sort(cs, pos+pack_length, length, &nr, &nr2); + key+= pack_length; + } + else + { + for (; pos < (uchar*) key ; pos++) + { + nr^=(ulong) ((((uint) nr & 63)+nr2)*((uint) *pos)) + (nr << 8); + nr2+=3; + } + } + } + DBUG_PRINT("exit", ("hash: 0x%lx", nr)); + return((ulong) nr); +} + + /* Calc hashvalue for a key in a record */ + +ulong hp_rec_hashnr(register HP_KEYDEF *keydef, register const byte *rec) +{ + ulong nr=1, nr2=4; + HA_KEYSEG *seg,*endseg; + + for (seg=keydef->seg,endseg=seg+keydef->keysegs ; seg < endseg ; seg++) + { + uchar *pos=(uchar*) rec+seg->start,*end=pos+seg->length; + if (seg->null_bit) + { + if (rec[seg->null_pos] & seg->null_bit) + { + nr^= (nr << 1) | 1; + continue; + } + } + if (seg->type == HA_KEYTYPE_TEXT) + { + CHARSET_INFO *cs= seg->charset; + uint char_length= seg->length; + if (cs->mbmaxlen > 1) + { + char_length= my_charpos(cs, pos, pos + char_length, + char_length / cs->mbmaxlen); + set_if_smaller(char_length, seg->length); /* QQ: ok to remove? */ + } + cs->coll->hash_sort(cs, pos, char_length, &nr, &nr2); + } + else if (seg->type == HA_KEYTYPE_VARTEXT1) /* Any VARCHAR segments */ + { + CHARSET_INFO *cs= seg->charset; + uint pack_length= seg->bit_start; + uint length= (pack_length == 1 ? (uint) *(uchar*) pos : uint2korr(pos)); + if (cs->mbmaxlen > 1) + { + uint char_length; + char_length= my_charpos(cs, pos + pack_length, + pos + pack_length + length, + seg->length/cs->mbmaxlen); + set_if_smaller(length, char_length); + } + cs->coll->hash_sort(cs, pos+pack_length, length, &nr, &nr2); + } + else + { + for (; pos < end ; pos++) + { + nr^=(ulong) ((((uint) nr & 63)+nr2)*((uint) *pos))+ (nr << 8); + nr2+=3; + } + } + } + DBUG_PRINT("exit", ("hash: 0x%lx", nr)); + return(nr); +} + +#else + +/* + * Fowler/Noll/Vo hash + * + * The basis of the hash algorithm was taken from an idea sent by email to the + * IEEE Posix P1003.2 mailing list from Phong Vo (kpv@research.att.com) and + * Glenn Fowler (gsf@research.att.com). Landon Curt Noll (chongo@toad.com) + * later improved on their algorithm. + * + * The magic is in the interesting relationship between the special prime + * 16777619 (2^24 + 403) and 2^32 and 2^8. + * + * This hash produces the fewest collisions of any function that we've seen so + * far, and works well on both numbers and strings. + */ + +ulong hp_hashnr(register HP_KEYDEF *keydef, register const byte *key) +{ + register ulong nr=0; + HA_KEYSEG *seg,*endseg; + + for (seg=keydef->seg,endseg=seg+keydef->keysegs ; seg < endseg ; seg++) + { + uchar *pos=(uchar*) key; + key+=seg->length; + if (seg->null_bit) + { + key++; + if (*pos) + { + nr^= (nr << 1) | 1; + continue; + } + pos++; + } + if (seg->type == HA_KEYTYPE_TEXT) + { + seg->charset->hash_sort(seg->charset,pos,((uchar*)key)-pos,&nr,NULL); + } + else if (seg->type == HA_KEYTYPE_VARTEXT1) /* Any VARCHAR segments */ + { + uint pack_length= 2; /* Key packing is constant */ + uint length= uint2korr(pos); + seg->charset->hash_sort(seg->charset, pos+pack_length, length, &nr, + NULL); + key+= pack_length; + } + else + { + for ( ; pos < (uchar*) key ; pos++) + { + nr *=16777619; + nr ^=(uint) *pos; + } + } + } + DBUG_PRINT("exit", ("hash: 0x%lx", nr)); + return(nr); +} + + /* Calc hashvalue for a key in a record */ + +ulong hp_rec_hashnr(register HP_KEYDEF *keydef, register const byte *rec) +{ + register ulong nr=0; + HA_KEYSEG *seg,*endseg; + + for (seg=keydef->seg,endseg=seg+keydef->keysegs ; seg < endseg ; seg++) + { + uchar *pos=(uchar*) rec+seg->start; + if (seg->null_bit) + { + if (rec[seg->null_pos] & seg->null_bit) + { + nr^= (nr << 1) | 1; + continue; + } + } + if (seg->type == HA_KEYTYPE_TEXT) + { + seg->charset->hash_sort(seg->charset,pos,((uchar*)key)-pos,&nr,NULL); + } + else if (seg->type == HA_KEYTYPE_VARTEXT1) /* Any VARCHAR segments */ + { + uint pack_length= seg->bit_start; + uint length= (pack_length == 1 ? (uint) *(uchar*) pos : uint2korr(pos)); + seg->charset->hash_sort(seg->charset, pos+pack_length, + length, &nr, NULL); + } + else + { + uchar *end= pos+seg->length; + for ( ; pos < end ; pos++) + { + nr *=16777619; + nr ^=(uint) *pos; + } + } + } + DBUG_PRINT("exit", ("hash: 0x%lx", nr)); + return(nr); +} + +#endif + + +/* + Compare keys for two records. Returns 0 if they are identical + + SYNOPSIS + hp_rec_key_cmp() + keydef Key definition + rec1 Record to compare + rec2 Other record to compare + diff_if_only_endspace_difference + Different number of end space is significant + + NOTES + diff_if_only_endspace_difference is used to allow us to insert + 'a' and 'a ' when there is an an unique key. + + RETURN + 0 Key is identical + <> 0 Key differes +*/ + +int hp_rec_key_cmp(HP_KEYDEF *keydef, const byte *rec1, const byte *rec2, + my_bool diff_if_only_endspace_difference) +{ + HA_KEYSEG *seg,*endseg; + + for (seg=keydef->seg,endseg=seg+keydef->keysegs ; seg < endseg ; seg++) + { + if (seg->null_bit) + { + if ((rec1[seg->null_pos] & seg->null_bit) != + (rec2[seg->null_pos] & seg->null_bit)) + return 1; + if (rec1[seg->null_pos] & seg->null_bit) + continue; + } + if (seg->type == HA_KEYTYPE_TEXT) + { + CHARSET_INFO *cs= seg->charset; + uint char_length1; + uint char_length2; + uchar *pos1= (uchar*)rec1 + seg->start; + uchar *pos2= (uchar*)rec2 + seg->start; + if (cs->mbmaxlen > 1) + { + uint char_length= seg->length / cs->mbmaxlen; + char_length1= my_charpos(cs, pos1, pos1 + seg->length, char_length); + set_if_smaller(char_length1, seg->length); + char_length2= my_charpos(cs, pos2, pos2 + seg->length, char_length); + set_if_smaller(char_length2, seg->length); + } + else + { + char_length1= char_length2= seg->length; + } + if (seg->charset->coll->strnncollsp(seg->charset, + pos1,char_length1, + pos2,char_length2, 0)) + return 1; + } + else if (seg->type == HA_KEYTYPE_VARTEXT1) /* Any VARCHAR segments */ + { + uchar *pos1= (uchar*) rec1 + seg->start; + uchar *pos2= (uchar*) rec2 + seg->start; + uint char_length1, char_length2; + uint pack_length= seg->bit_start; + CHARSET_INFO *cs= seg->charset; + if (pack_length == 1) + { + char_length1= (uint) *(uchar*) pos1++; + char_length2= (uint) *(uchar*) pos2++; + } + else + { + char_length1= uint2korr(pos1); + char_length2= uint2korr(pos2); + pos1+= 2; + pos2+= 2; + } + if (cs->mbmaxlen > 1) + { + uint char_length= seg->length / cs->mbmaxlen; + char_length1= my_charpos(cs, pos1, pos1 + char_length1, char_length); + set_if_smaller(char_length1, seg->length); + char_length2= my_charpos(cs, pos2, pos2 + char_length2, char_length); + set_if_smaller(char_length2, seg->length); + } + + if (cs->coll->strnncollsp(seg->charset, + pos1, char_length1, + pos2, char_length2, + seg->flag & HA_END_SPACE_ARE_EQUAL ? + 0 : diff_if_only_endspace_difference)) + return 1; + } + else + { + if (bcmp(rec1+seg->start,rec2+seg->start,seg->length)) + return 1; + } + } + return 0; +} + + /* Compare a key in a record to a whole key */ + +int hp_key_cmp(HP_KEYDEF *keydef, const byte *rec, const byte *key) +{ + HA_KEYSEG *seg,*endseg; + + for (seg=keydef->seg,endseg=seg+keydef->keysegs ; + seg < endseg ; + key+= (seg++)->length) + { + if (seg->null_bit) + { + int found_null=test(rec[seg->null_pos] & seg->null_bit); + if (found_null != (int) *key++) + return 1; + if (found_null) + continue; + } + if (seg->type == HA_KEYTYPE_TEXT) + { + CHARSET_INFO *cs= seg->charset; + uint char_length_key; + uint char_length_rec; + uchar *pos= (uchar*) rec + seg->start; + if (cs->mbmaxlen > 1) + { + uint char_length= seg->length / cs->mbmaxlen; + char_length_key= my_charpos(cs, key, key + seg->length, char_length); + set_if_smaller(char_length_key, seg->length); + char_length_rec= my_charpos(cs, pos, pos + seg->length, char_length); + set_if_smaller(char_length_rec, seg->length); + } + else + { + char_length_key= seg->length; + char_length_rec= seg->length; + } + + if (seg->charset->coll->strnncollsp(seg->charset, + (uchar*) pos, char_length_rec, + (uchar*) key, char_length_key, 0)) + return 1; + } + else if (seg->type == HA_KEYTYPE_VARTEXT1) /* Any VARCHAR segments */ + { + uchar *pos= (uchar*) rec + seg->start; + CHARSET_INFO *cs= seg->charset; + uint pack_length= seg->bit_start; + uint char_length_rec= (pack_length == 1 ? (uint) *(uchar*) pos : + uint2korr(pos)); + /* Key segments are always packed with 2 bytes */ + uint char_length_key= uint2korr(key); + pos+= pack_length; + key+= 2; /* skip key pack length */ + if (cs->mbmaxlen > 1) + { + uint char_length= seg->length / cs->mbmaxlen; + char_length_key= my_charpos(cs, key, key + char_length_key, + char_length); + set_if_smaller(char_length_key, seg->length); + char_length_rec= my_charpos(cs, pos, pos + char_length_rec, + char_length); + set_if_smaller(char_length_rec, seg->length); + } + + if (cs->coll->strnncollsp(seg->charset, + (uchar*) pos, char_length_rec, + (uchar*) key, char_length_key, 0)) + return 1; + } + else + { + if (bcmp(rec+seg->start,key,seg->length)) + return 1; + } + } + return 0; +} + + + /* Copy a key from a record to a keybuffer */ + +void hp_make_key(HP_KEYDEF *keydef, byte *key, const byte *rec) +{ + HA_KEYSEG *seg,*endseg; + + for (seg=keydef->seg,endseg=seg+keydef->keysegs ; seg < endseg ; seg++) + { + CHARSET_INFO *cs= seg->charset; + uint char_length= seg->length; + uchar *pos= (uchar*) rec + seg->start; + if (seg->null_bit) + *key++= test(rec[seg->null_pos] & seg->null_bit); + if (cs->mbmaxlen > 1) + { + char_length= my_charpos(cs, pos, pos + seg->length, + char_length / cs->mbmaxlen); + set_if_smaller(char_length, seg->length); /* QQ: ok to remove? */ + } + if (seg->type == HA_KEYTYPE_VARTEXT1) + char_length+= seg->bit_start; /* Copy also length */ + memcpy(key,rec+seg->start,(size_t) char_length); + key+= char_length; + } +} + +#define FIX_LENGTH(cs, pos, length, char_length) \ + do { \ + if (length > char_length) \ + char_length= my_charpos(cs, pos, pos+length, char_length); \ + set_if_smaller(char_length,length); \ + } while(0) + + +uint hp_rb_make_key(HP_KEYDEF *keydef, byte *key, + const byte *rec, byte *recpos) +{ + byte *start_key= key; + HA_KEYSEG *seg, *endseg; + + for (seg= keydef->seg, endseg= seg + keydef->keysegs; seg < endseg; seg++) + { + uint char_length; + if (seg->null_bit) + { + if (!(*key++= 1 - test(rec[seg->null_pos] & seg->null_bit))) + continue; + } + if (seg->flag & HA_SWAP_KEY) + { + uint length= seg->length; + byte *pos= (byte*) rec + seg->start; + +#ifdef HAVE_ISNAN + if (seg->type == HA_KEYTYPE_FLOAT) + { + float nr; + float4get(nr, pos); + if (isnan(nr)) + { + /* Replace NAN with zero */ + bzero(key, length); + key+= length; + continue; + } + } + else if (seg->type == HA_KEYTYPE_DOUBLE) + { + double nr; + float8get(nr, pos); + if (isnan(nr)) + { + bzero(key, length); + key+= length; + continue; + } + } +#endif + pos+= length; + while (length--) + { + *key++= *--pos; + } + continue; + } + + if (seg->flag & HA_VAR_LENGTH_PART) + { + uchar *pos= (uchar*) rec + seg->start; + uint length= seg->length; + uint pack_length= seg->bit_start; + uint tmp_length= (pack_length == 1 ? (uint) *(uchar*) pos : + uint2korr(pos)); + CHARSET_INFO *cs= seg->charset; + char_length= length/cs->mbmaxlen; + + pos+= pack_length; /* Skip VARCHAR length */ + set_if_smaller(length,tmp_length); + FIX_LENGTH(cs, pos, length, char_length); + store_key_length_inc(key,char_length); + memcpy((byte*) key,(byte*) pos,(size_t) char_length); + key+= char_length; + continue; + } + + char_length= seg->length; + if (seg->charset->mbmaxlen > 1) + { + char_length= my_charpos(seg->charset, + rec + seg->start, rec + seg->start + char_length, + char_length / seg->charset->mbmaxlen); + set_if_smaller(char_length, seg->length); /* QQ: ok to remove? */ + if (char_length < seg->length) + seg->charset->cset->fill(seg->charset, (char*) key + char_length, + seg->length - char_length, ' '); + } + memcpy(key, rec + seg->start, (size_t) char_length); + key+= seg->length; + } + memcpy(key, &recpos, sizeof(byte*)); + return key - start_key; +} + + +uint hp_rb_pack_key(HP_KEYDEF *keydef, uchar *key, const uchar *old, + uint k_len) +{ + HA_KEYSEG *seg, *endseg; + uchar *start_key= key; + + for (seg= keydef->seg, endseg= seg + keydef->keysegs; + seg < endseg && (int) k_len > 0; old+= seg->length, seg++) + { + uint char_length; + if (seg->null_bit) + { + k_len--; + if (!(*key++= (char) 1 - *old++)) + { + k_len-= seg->length; + continue; + } + } + if (seg->flag & HA_SWAP_KEY) + { + uint length= seg->length; + byte *pos= (byte*) old + length; + + k_len-= length; + while (length--) + { + *key++= *--pos; + } + continue; + } + if (seg->flag & (HA_VAR_LENGTH_PART | HA_BLOB_PART)) + { + /* Length of key-part used with heap_rkey() always 2 */ + uint tmp_length=uint2korr(old); + uint length= seg->length; + CHARSET_INFO *cs= seg->charset; + char_length= length/cs->mbmaxlen; + + k_len-= 2+length; + old+= 2; + set_if_smaller(length,tmp_length); /* Safety */ + FIX_LENGTH(cs, old, length, char_length); + store_key_length_inc(key,char_length); + memcpy((byte*) key, old,(size_t) char_length); + key+= char_length; + continue; + } + char_length= seg->length; + if (seg->charset->mbmaxlen > 1) + { + char_length= my_charpos(seg->charset, old, old+char_length, + char_length / seg->charset->mbmaxlen); + set_if_smaller(char_length, seg->length); /* QQ: ok to remove? */ + if (char_length < seg->length) + seg->charset->cset->fill(seg->charset, (char*) key + char_length, + seg->length - char_length, ' '); + } + memcpy(key, old, (size_t) char_length); + key+= seg->length; + k_len-= seg->length; + } + return key - start_key; +} + + +uint hp_rb_key_length(HP_KEYDEF *keydef, + const byte *key __attribute__((unused))) +{ + return keydef->length; +} + + +uint hp_rb_null_key_length(HP_KEYDEF *keydef, const byte *key) +{ + const byte *start_key= key; + HA_KEYSEG *seg, *endseg; + + for (seg= keydef->seg, endseg= seg + keydef->keysegs; seg < endseg; seg++) + { + if (seg->null_bit && !*key++) + continue; + key+= seg->length; + } + return key - start_key; +} + + +uint hp_rb_var_key_length(HP_KEYDEF *keydef, const byte *key) +{ + const byte *start_key= key; + HA_KEYSEG *seg, *endseg; + + for (seg= keydef->seg, endseg= seg + keydef->keysegs; seg < endseg; seg++) + { + uint length= seg->length; + if (seg->null_bit && !*key++) + continue; + if (seg->flag & (HA_VAR_LENGTH_PART | HA_BLOB_PART)) + { + get_key_length(length, key); + } + key+= length; + } + return key - start_key; +} + + +/* + Test if any of the key parts are NULL. + Return: + 1 if any of the key parts was NULL + 0 otherwise +*/ + +my_bool hp_if_null_in_key(HP_KEYDEF *keydef, const byte *record) +{ + HA_KEYSEG *seg,*endseg; + for (seg=keydef->seg,endseg=seg+keydef->keysegs ; seg < endseg ; seg++) + { + if (seg->null_bit && (record[seg->null_pos] & seg->null_bit)) + return 1; + } + return 0; +} + + +/* + Update auto_increment info + + SYNOPSIS + update_auto_increment() + info MyISAM handler + record Row to update + + IMPLEMENTATION + Only replace the auto_increment value if it is higher than the previous + one. For signed columns we don't update the auto increment value if it's + less than zero. +*/ + +void heap_update_auto_increment(HP_INFO *info, const byte *record) +{ + ulonglong value= 0; /* Store unsigned values here */ + longlong s_value= 0; /* Store signed values here */ + + HA_KEYSEG *keyseg= info->s->keydef[info->s->auto_key - 1].seg; + const uchar *key= (uchar*) record + keyseg->start; + + switch (info->s->auto_key_type) { + case HA_KEYTYPE_INT8: + s_value= (longlong) *(char*)key; + break; + case HA_KEYTYPE_BINARY: + value=(ulonglong) *(uchar*) key; + break; + case HA_KEYTYPE_SHORT_INT: + s_value= (longlong) sint2korr(key); + break; + case HA_KEYTYPE_USHORT_INT: + value=(ulonglong) uint2korr(key); + break; + case HA_KEYTYPE_LONG_INT: + s_value= (longlong) sint4korr(key); + break; + case HA_KEYTYPE_ULONG_INT: + value=(ulonglong) uint4korr(key); + break; + case HA_KEYTYPE_INT24: + s_value= (longlong) sint3korr(key); + break; + case HA_KEYTYPE_UINT24: + value=(ulonglong) uint3korr(key); + break; + case HA_KEYTYPE_FLOAT: /* This shouldn't be used */ + { + float f_1; + float4get(f_1,key); + /* Ignore negative values */ + value = (f_1 < (float) 0.0) ? 0 : (ulonglong) f_1; + break; + } + case HA_KEYTYPE_DOUBLE: /* This shouldn't be used */ + { + double f_1; + float8get(f_1,key); + /* Ignore negative values */ + value = (f_1 < 0.0) ? 0 : (ulonglong) f_1; + break; + } + case HA_KEYTYPE_LONGLONG: + s_value= sint8korr(key); + break; + case HA_KEYTYPE_ULONGLONG: + value= uint8korr(key); + break; + default: + DBUG_ASSERT(0); + value=0; /* Error */ + break; + } + + /* + The following code works becasue if s_value < 0 then value is 0 + and if s_value == 0 then value will contain either s_value or the + correct value. + */ + set_if_bigger(info->s->auto_increment, + (s_value > 0) ? (ulonglong) s_value : value); +} |