1 /* Copyright (c) 2011, 2021, Oracle and/or its affiliates. 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 #include "my_icp.h" /* ICP_RESULT */ 33 34 /* 35 There is a hard limit for the maximum number of keys as there are only 36 8 bits in the index file header for the number of keys in a table. 37 This means that 0..255 keys can exist for a table. The idea of 38 HA_MAX_POSSIBLE_KEY is to ensure that one can use myisamchk & tools on 39 a MyISAM table for which one has more keys than MyISAM is normally 40 compiled for. If you don't have this, you will get a core dump when 41 running myisamchk compiled for 128 keys on a table with 255 keys. 42 */ 43 44 #define HA_MAX_POSSIBLE_KEY 255 /* For myisamchk */ 45 /* 46 The following defines can be increased if necessary. 47 But beware the dependency of MI_MAX_POSSIBLE_KEY_BUFF and HA_MAX_KEY_LENGTH. 48 */ 49 50 #define HA_MAX_KEY_LENGTH 4000 /* Max length in bytes */ 51 #define HA_MAX_KEY_SEG 16 /* Max segments for key */ 52 53 #define HA_MAX_POSSIBLE_KEY_BUFF (HA_MAX_KEY_LENGTH + 24+ 6+6) 54 #define HA_MAX_KEY_BUFF (HA_MAX_KEY_LENGTH+HA_MAX_KEY_SEG*6+8+8) 55 56 typedef struct st_HA_KEYSEG /* Key-portion */ 57 { 58 const CHARSET_INFO *charset; 59 uint32 start; /* Start of key in record */ 60 uint32 null_pos; /* position to NULL indicator */ 61 uint16 bit_pos; /* Position to bit part */ 62 uint16 flag; 63 uint16 length; /* Keylength */ 64 uint16 language; 65 uint8 type; /* Type of key (for sort) */ 66 uint8 null_bit; /* bitmask to test for NULL */ 67 uint8 bit_start,bit_end; /* if bit field */ 68 uint8 bit_length; /* Length of bit part */ 69 } HA_KEYSEG; 70 71 #define get_key_length(length,key) \ 72 { if (*(uchar*) (key) != 255) \ 73 length= (uint) *(uchar*) ((key)++); \ 74 else \ 75 { length= mi_uint2korr((key)+1); (key)+=3; } \ 76 } 77 78 #define get_key_length_rdonly(length,key) \ 79 { if (*(uchar*) (key) != 255) \ 80 length= ((uint) *(uchar*) ((key))); \ 81 else \ 82 { length= mi_uint2korr((key)+1); } \ 83 } 84 85 #define get_key_pack_length(length,length_pack,key) \ 86 { if (*(uchar*) (key) != 255) \ 87 { length= (uint) *(uchar*) ((key)++); length_pack= 1; }\ 88 else \ 89 { length=mi_uint2korr((key)+1); (key)+= 3; length_pack= 3; } \ 90 } 91 92 #define store_key_length_inc(key,length) \ 93 { if ((length) < 255) \ 94 { *(key)++= (length); } \ 95 else \ 96 { *(key)=255; mi_int2store((key)+1,(length)); (key)+=3; } \ 97 } 98 99 #define size_to_store_key_length(length) ((length) < 255 ? 1 : 3) 100 101 #define get_rec_bits(bit_ptr, bit_ofs, bit_len) \ 102 (((((uint16) (bit_ptr)[1] << 8) | (uint16) (bit_ptr)[0]) >> (bit_ofs)) & \ 103 ((1 << (bit_len)) - 1)) 104 105 #define set_rec_bits(bits, bit_ptr, bit_ofs, bit_len) \ 106 { \ 107 (bit_ptr)[0]= ((bit_ptr)[0] & ~(((1 << (bit_len)) - 1) << (bit_ofs))) | \ 108 ((bits) << (bit_ofs)); \ 109 if ((bit_ofs) + (bit_len) > 8) \ 110 (bit_ptr)[1]= ((bit_ptr)[1] & ~((1 << ((bit_len) - 8 + (bit_ofs))) - 1)) | \ 111 ((bits) >> (8 - (bit_ofs))); \ 112 } 113 114 #define clr_rec_bits(bit_ptr, bit_ofs, bit_len) \ 115 set_rec_bits(0, bit_ptr, bit_ofs, bit_len) 116 117 extern int ha_compare_text(const CHARSET_INFO *, uchar *, uint, uchar *, uint , 118 my_bool, my_bool); 119 extern int ha_key_cmp(HA_KEYSEG *keyseg, uchar *a, 120 uchar *b, uint key_length, uint nextflag, 121 uint *diff_pos); 122 123 /* 124 Inside an in-memory data record, memory pointers to pieces of the 125 record (like BLOBs) are stored in their native byte order and in 126 this amount of bytes. 127 */ 128 #define portable_sizeof_char_ptr 8 129 130 #ifdef __cplusplus 131 } 132 #endif 133 134 #endif /* _my_compare_h */ 135