diff options
Diffstat (limited to 'mysys/my_handler.c')
| -rw-r--r-- | mysys/my_handler.c | 404 |
1 files changed, 404 insertions, 0 deletions
diff --git a/mysys/my_handler.c b/mysys/my_handler.c new file mode 100644 index 00000000000..5b68b427f3a --- /dev/null +++ b/mysys/my_handler.c @@ -0,0 +1,404 @@ +/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public + License as published by the Free Software Foundation; either + version 2 of the License, or (at your option) any later version. + + This library 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with this library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, + MA 02111-1307, USA */ + +#include "my_handler.h" + +int mi_compare_text(CHARSET_INFO *charset_info, uchar *a, uint a_length, + uchar *b, uint b_length, my_bool part_key) +{ + int flag; + +#ifdef USE_STRCOLL + if (use_strcoll(charset_info)) + { + if (part_key && b_length < a_length) + a_length=b_length; + return my_strnncoll(charset_info, a, a_length, b, b_length); + } + else +#endif + { + uint length= min(a_length,b_length); + uchar *end= a+ length; + uchar *sort_order=charset_info->sort_order; + while (a < end) + if ((flag= (int) sort_order[*a++] - (int) sort_order[*b++])) + return flag; + } + if (part_key && b_length < a_length) + return 0; + return (int) (a_length-b_length); +} + +static int compare_bin(uchar *a, uint a_length, uchar *b, uint b_length, + my_bool part_key) +{ + uint length= min(a_length,b_length); + uchar *end= a+ length; + int flag; + + while (a < end) + if ((flag= (int) *a++ - (int) *b++)) + return flag; + if (part_key && b_length < a_length) + return 0; + return (int) (a_length-b_length); +} + +#define FCMP(A,B) ((int) (A) - (int) (B)) + +/* + Compare two keys + Returns <0, 0, >0 acording to which is bigger + Key_length specifies length of key to use. Number-keys can't be splited + If flag <> SEARCH_FIND compare also position +*/ + +int ha_key_cmp(register HA_KEYSEG *keyseg, register uchar *a, + register uchar *b, uint key_length, uint nextflag, + uint *diff_pos) +{ + int flag; + int16 s_1,s_2; + int32 l_1,l_2; + uint32 u_1,u_2; + float f_1,f_2; + double d_1,d_2; + uint next_key_length; + + *diff_pos=0; + for ( ; (int) key_length >0 ; key_length=next_key_length, keyseg++) + { + uchar *end; + uint piks=! (keyseg->flag & HA_NO_SORT); + (*diff_pos)++; + + /* Handle NULL part */ + if (keyseg->null_bit) + { + key_length--; + if (*a != *b && piks) + { + flag = (int) *a - (int) *b; + return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag); + } + b++; + if (!*a++) /* If key was NULL */ + { + if (nextflag == (SEARCH_FIND | SEARCH_UPDATE)) + nextflag=SEARCH_SAME; /* Allow duplicate keys */ + next_key_length=key_length; + continue; /* To next key part */ + } + } + end= a+ min(keyseg->length,key_length); + next_key_length=key_length-keyseg->length; + + switch ((enum ha_base_keytype) keyseg->type) { + case HA_KEYTYPE_TEXT: /* Ascii; Key is converted */ + if (keyseg->flag & HA_SPACE_PACK) + { + int a_length,b_length,pack_length; + get_key_length(a_length,a); + get_key_pack_length(b_length,pack_length,b); + next_key_length=key_length-b_length-pack_length; + + if (piks && + (flag= mi_compare_text(keyseg->charset,a,a_length,b,b_length, + (my_bool) ((nextflag & SEARCH_PREFIX) && + next_key_length <= 0)))) + return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag); + a+=a_length; + b+=b_length; + break; + } + else + { + uint length=(uint) (end-a), a_length=length, b_length=length; + if (!(nextflag & SEARCH_PREFIX)) + { + while (a_length && a[a_length-1] == ' ') + a_length--; + while (b_length && b[b_length-1] == ' ') + b_length--; + } + if (piks && + (flag= mi_compare_text(keyseg->charset,a,a_length,b,b_length, + (my_bool) ((nextflag & SEARCH_PREFIX) && + next_key_length <= 0)))) + return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag); + a=end; + b+=length; + } + break; + case HA_KEYTYPE_BINARY: + if (keyseg->flag & HA_SPACE_PACK) + { + int a_length,b_length,pack_length; + get_key_length(a_length,a); + get_key_pack_length(b_length,pack_length,b); + next_key_length=key_length-b_length-pack_length; + + if (piks && + (flag=compare_bin(a,a_length,b,b_length, + (my_bool) ((nextflag & SEARCH_PREFIX) && + next_key_length <= 0)))) + return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag); + a+=a_length; + b+=b_length; + break; + } + else + { + uint length=keyseg->length; + if (piks && + (flag=compare_bin(a,length,b,length, + (my_bool) ((nextflag & SEARCH_PREFIX) && + next_key_length <= 0)))) + return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag); + a+=length; + b+=length; + } + break; + case HA_KEYTYPE_VARTEXT: + { + int a_length,b_length,pack_length; + get_key_length(a_length,a); + get_key_pack_length(b_length,pack_length,b); + next_key_length=key_length-b_length-pack_length; + + if (piks && + (flag= mi_compare_text(keyseg->charset,a,a_length,b,b_length, + (my_bool) ((nextflag & SEARCH_PREFIX) && + next_key_length <= 0)))) + return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag); + a+=a_length; + b+=b_length; + break; + } + break; + case HA_KEYTYPE_VARBINARY: + { + int a_length,b_length,pack_length; + get_key_length(a_length,a); + get_key_pack_length(b_length,pack_length,b); + next_key_length=key_length-b_length-pack_length; + + if (piks && + (flag=compare_bin(a,a_length,b,b_length, + (my_bool) ((nextflag & SEARCH_PREFIX) && + next_key_length <= 0)))) + return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag); + a+=a_length; + b+=b_length; + break; + } + break; + case HA_KEYTYPE_INT8: + { + int i_1= (int) *((signed char*) a); + int i_2= (int) *((signed char*) b); + if (piks && (flag = CMP_NUM(i_1,i_2))) + return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag); + a= end; + b++; + break; + } + case HA_KEYTYPE_SHORT_INT: + s_1= mi_sint2korr(a); + s_2= mi_sint2korr(b); + if (piks && (flag = CMP_NUM(s_1,s_2))) + return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag); + a= end; + b+= 2; /* sizeof(short int); */ + break; + case HA_KEYTYPE_USHORT_INT: + { + uint16 us_1,us_2; + us_1= mi_sint2korr(a); + us_2= mi_sint2korr(b); + if (piks && (flag = CMP_NUM(us_1,us_2))) + return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag); + a= end; + b+=2; /* sizeof(short int); */ + break; + } + case HA_KEYTYPE_LONG_INT: + l_1= mi_sint4korr(a); + l_2= mi_sint4korr(b); + if (piks && (flag = CMP_NUM(l_1,l_2))) + return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag); + a= end; + b+= 4; /* sizeof(long int); */ + break; + case HA_KEYTYPE_ULONG_INT: + u_1= mi_sint4korr(a); + u_2= mi_sint4korr(b); + if (piks && (flag = CMP_NUM(u_1,u_2))) + return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag); + a= end; + b+= 4; /* sizeof(long int); */ + break; + case HA_KEYTYPE_INT24: + l_1=mi_sint3korr(a); + l_2=mi_sint3korr(b); + if (piks && (flag = CMP_NUM(l_1,l_2))) + return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag); + a= end; + b+= 3; + break; + case HA_KEYTYPE_UINT24: + l_1=mi_uint3korr(a); + l_2=mi_uint3korr(b); + if (piks && (flag = CMP_NUM(l_1,l_2))) + return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag); + a= end; + b+= 3; + break; + case HA_KEYTYPE_FLOAT: + mi_float4get(f_1,a); + mi_float4get(f_2,b); + if (piks && (flag = CMP_NUM(f_1,f_2))) + return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag); + a= end; + b+= 4; /* sizeof(float); */ + break; + case HA_KEYTYPE_DOUBLE: + mi_float8get(d_1,a); + mi_float8get(d_2,b); + if (piks && (flag = CMP_NUM(d_1,d_2))) + return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag); + a= end; + b+= 8; /* sizeof(double); */ + break; + case HA_KEYTYPE_NUM: /* Numeric key */ + { + int swap_flag= 0; + int alength,blength; + + if (keyseg->flag & HA_REVERSE_SORT) + { + swap(uchar*,a,b); + swap_flag=1; /* Remember swap of a & b */ + end= a+ (int) (end-b); + } + if (keyseg->flag & HA_SPACE_PACK) + { + alength= *a++; blength= *b++; + end=a+alength; + next_key_length=key_length-blength-1; + } + else + { + alength= (int) (end-a); + blength=keyseg->length; + /* remove pre space from keys */ + for ( ; alength && *a == ' ' ; a++, alength--) ; + for ( ; blength && *b == ' ' ; b++, blength--) ; + } + + if (piks) + { + if (*a == '-') + { + if (*b != '-') + return -1; + a++; b++; + swap(uchar*,a,b); + swap(int,alength,blength); + swap_flag=1-swap_flag; + alength--; blength--; + end=a+alength; + } + else if (*b == '-') + return 1; + while (alength && (*a == '+' || *a == '0')) + { + a++; alength--; + } + while (blength && (*b == '+' || *b == '0')) + { + b++; blength--; + } + if (alength != blength) + return (alength < blength) ? -1 : 1; + while (a < end) + if (*a++ != *b++) + return ((int) a[-1] - (int) b[-1]); + } + else + { + b+=(end-a); + a=end; + } + + if (swap_flag) /* Restore pointers */ + swap(uchar*,a,b); + break; + } +#ifdef HAVE_LONG_LONG + case HA_KEYTYPE_LONGLONG: + { + longlong ll_a,ll_b; + ll_a= mi_sint8korr(a); + ll_b= mi_sint8korr(b); + if (piks && (flag = CMP_NUM(ll_a,ll_b))) + return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag); + a= end; + b+= 8; + break; + } + case HA_KEYTYPE_ULONGLONG: + { + ulonglong ll_a,ll_b; + ll_a= mi_uint8korr(a); + ll_b= mi_uint8korr(b); + if (piks && (flag = CMP_NUM(ll_a,ll_b))) + return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag); + a= end; + b+= 8; + break; + } +#endif + case HA_KEYTYPE_END: /* Ready */ + goto end; /* diff_pos is incremented */ + } + } + (*diff_pos)++; +end: + if (!(nextflag & SEARCH_FIND)) + { + uint i; + if (nextflag & (SEARCH_NO_FIND | SEARCH_LAST)) /* Find record after key */ + return (nextflag & (SEARCH_BIGGER | SEARCH_LAST)) ? -1 : 1; + flag=0; + for (i=keyseg->length ; i-- > 0 ; ) + { + if (*a++ != *b++) + { + flag= FCMP(a[-1],b[-1]); + break; + } + } + if (nextflag & SEARCH_SAME) + return (flag); /* read same */ + if (nextflag & SEARCH_BIGGER) + return (flag <= 0 ? -1 : 1); /* read next */ + return (flag < 0 ? -1 : 1); /* read previous */ + } + return 0; +} /* ha_key_cmp */ |