/* 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 /* 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 char_length= (uint) ((uchar*) key - pos); if (cs->mbmaxlen > 1) { uint length= char_length; char_length= my_charpos(cs, pos, pos + length, length/cs->mbmaxlen); set_if_smaller(char_length, length); /* QQ: ok to remove? */ } cs->coll->hash_sort(cs, pos, char_length, &nr, &nr2); } else { for (; pos < (uchar*) key ; pos++) { nr^=(ulong) ((((uint) nr & 63)+nr2)*((uint) *pos)) + (nr << 8); nr2+=3; } } } return((ulong) nr); } /* Calc hashvalue for a key in a record */ ulong hp_rec_hashnr(register HP_KEYDEF *keydef, register const byte *rec) { /*register*/ 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 { for (; pos < end ; pos++) { nr^=(ulong) ((((uint) nr & 63)+nr2)*((uint) *pos))+ (nr << 8); nr2+=3; } } } return((ulong) 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 { for ( ; pos < (uchar*) key ; pos++) { nr *=16777619; nr ^=(uint) *pos; } } } return((ulong) 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,*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) { seg->charset->hash_sort(seg->charset,pos,((uchar*)key)-pos,&nr,NULL); } else { for ( ; pos < end ; pos++) { nr *=16777619; nr ^=(uint) *pos; } } } return((ulong) nr); } #endif /* Compare keys for two records. Returns 0 if they are identical */ int hp_rec_key_cmp(HP_KEYDEF *keydef, const byte *rec1, const byte *rec2) { 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); /* QQ: ok to remove? */ char_length2= my_charpos(cs, pos2, pos2 + seg->length, char_length); set_if_smaller(char_length2, seg->length); /* QQ: ok to remove? */ } else { char_length1= char_length2= seg->length; } if (seg->charset->coll->strnncollsp(seg->charset, pos1,char_length1, pos2,char_length2)) 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)) 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? */ } memcpy(key,rec+seg->start,(size_t) char_length); key+= char_length; } } 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; } 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; } 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; } /* 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); }