1 /* Copyright (c) 2011, 2013, Oracle and/or its affiliates. All rights reserved. 2 3 This program is free software; you can redistribute it and/or modify 4 it under the terms of the GNU General Public License, version 2.0, 5 as published by the Free Software Foundation. 6 7 This program is also distributed with certain software (including 8 but not limited to OpenSSL) that is licensed under separate terms, 9 as designated in a particular file or component or in included license 10 documentation. The authors of MySQL hereby grant you an additional 11 permission to link the program and your derivative works with the 12 separately licensed software that they have included with MySQL. 13 14 This program is distributed in the hope that it will be useful, 15 but WITHOUT ANY WARRANTY; without even the implied warranty of 16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 GNU General Public License, version 2.0, for more details. 18 19 You should have received a copy of the GNU General Public License 20 along with this program; if not, write to the Free Software 21 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA */ 22 23 #ifndef _my_compare_h 24 #define _my_compare_h 25 26 #include "myisampack.h" 27 #ifdef __cplusplus 28 extern "C" { 29 #endif 30 31 #include "m_ctype.h" /* CHARSET_INFO */ 32 33 /* 34 There is a hard limit for the maximum number of keys as there are only 35 8 bits in the index file header for the number of keys in a table. 36 This means that 0..255 keys can exist for a table. The idea of 37 HA_MAX_POSSIBLE_KEY is to ensure that one can use myisamchk & tools on 38 a MyISAM table for which one has more keys than MyISAM is normally 39 compiled for. If you don't have this, you will get a core dump when 40 running myisamchk compiled for 128 keys on a table with 255 keys. 41 */ 42 43 #define HA_MAX_POSSIBLE_KEY 255 /* For myisamchk */ 44 /* 45 The following defines can be increased if necessary. 46 But beware the dependency of MI_MAX_POSSIBLE_KEY_BUFF and HA_MAX_KEY_LENGTH. 47 */ 48 49 #define HA_MAX_KEY_LENGTH 4000 /* Max length in bytes */ 50 #define HA_MAX_KEY_SEG 16 /* Max segments for key */ 51 52 #define HA_MAX_POSSIBLE_KEY_BUFF (HA_MAX_KEY_LENGTH + 24+ 6+6) 53 #define HA_MAX_KEY_BUFF (HA_MAX_KEY_LENGTH+HA_MAX_KEY_SEG*6+8+8) 54 55 typedef struct st_HA_KEYSEG /* Key-portion */ 56 { 57 const CHARSET_INFO *charset; 58 uint32 start; /* Start of key in record */ 59 uint32 null_pos; /* position to NULL indicator */ 60 uint16 bit_pos; /* Position to bit part */ 61 uint16 flag; 62 uint16 length; /* Keylength */ 63 uint16 language; 64 uint8 type; /* Type of key (for sort) */ 65 uint8 null_bit; /* bitmask to test for NULL */ 66 uint8 bit_start,bit_end; /* if bit field */ 67 uint8 bit_length; /* Length of bit part */ 68 } HA_KEYSEG; 69 70 #define get_key_length(length,key) \ 71 { if (*(uchar*) (key) != 255) \ 72 length= (uint) *(uchar*) ((key)++); \ 73 else \ 74 { length= mi_uint2korr((key)+1); (key)+=3; } \ 75 } 76 77 #define get_key_length_rdonly(length,key) \ 78 { if (*(uchar*) (key) != 255) \ 79 length= ((uint) *(uchar*) ((key))); \ 80 else \ 81 { length= mi_uint2korr((key)+1); } \ 82 } 83 84 #define get_key_pack_length(length,length_pack,key) \ 85 { if (*(uchar*) (key) != 255) \ 86 { length= (uint) *(uchar*) ((key)++); length_pack= 1; }\ 87 else \ 88 { length=mi_uint2korr((key)+1); (key)+= 3; length_pack= 3; } \ 89 } 90 91 #define store_key_length_inc(key,length) \ 92 { if ((length) < 255) \ 93 { *(key)++= (length); } \ 94 else \ 95 { *(key)=255; mi_int2store((key)+1,(length)); (key)+=3; } \ 96 } 97 98 #define size_to_store_key_length(length) ((length) < 255 ? 1 : 3) 99 100 #define get_rec_bits(bit_ptr, bit_ofs, bit_len) \ 101 (((((uint16) (bit_ptr)[1] << 8) | (uint16) (bit_ptr)[0]) >> (bit_ofs)) & \ 102 ((1 << (bit_len)) - 1)) 103 104 #define set_rec_bits(bits, bit_ptr, bit_ofs, bit_len) \ 105 { \ 106 (bit_ptr)[0]= ((bit_ptr)[0] & ~(((1 << (bit_len)) - 1) << (bit_ofs))) | \ 107 ((bits) << (bit_ofs)); \ 108 if ((bit_ofs) + (bit_len) > 8) \ 109 (bit_ptr)[1]= ((bit_ptr)[1] & ~((1 << ((bit_len) - 8 + (bit_ofs))) - 1)) | \ 110 ((bits) >> (8 - (bit_ofs))); \ 111 } 112 113 #define clr_rec_bits(bit_ptr, bit_ofs, bit_len) \ 114 set_rec_bits(0, bit_ptr, bit_ofs, bit_len) 115 116 extern int ha_compare_text(const CHARSET_INFO *, uchar *, uint, uchar *, uint , 117 my_bool, my_bool); 118 extern int ha_key_cmp(register HA_KEYSEG *keyseg, register uchar *a, 119 register uchar *b, uint key_length, uint nextflag, 120 uint *diff_pos); 121 122 /* 123 Inside an in-memory data record, memory pointers to pieces of the 124 record (like BLOBs) are stored in their native byte order and in 125 this amount of bytes. 126 */ 127 #define portable_sizeof_char_ptr 8 128 129 130 /** 131 Return values of index_cond_func_xxx functions. 132 133 0=ICP_NO_MATCH - index tuple doesn't satisfy the pushed index condition (the 134 engine should discard the tuple and go to the next one) 135 1=ICP_MATCH - index tuple satisfies the pushed index condition (the engine 136 should fetch and return the record) 137 2=ICP_OUT_OF_RANGE - index tuple is out range that we're scanning, e.g. this 138 if we're scanning "t.key BETWEEN 10 AND 20" and got a 139 "t.key=21" tuple (the engine should stop scanning and return 140 HA_ERR_END_OF_FILE right away). 141 */ 142 143 typedef enum icp_result { 144 ICP_NO_MATCH, 145 ICP_MATCH, 146 ICP_OUT_OF_RANGE 147 } ICP_RESULT; 148 149 150 #ifdef __cplusplus 151 } 152 #endif 153 154 #endif /* _my_compare_h */ 155