summaryrefslogtreecommitdiff
path: root/include/my_handler.h
blob: ae56331df86c996caa54e25430196464a4399e6d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
/* Copyright (C) 2002-2006 MySQL 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; version 2
   of the License.

   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 */

#ifndef _my_handler_h
#define _my_handler_h

#include "myisampack.h"
#ifdef	__cplusplus
extern "C" {
#endif

/*
  There is a hard limit for the maximum number of keys as there are only
  8 bits in the index file header for the number of keys in a table.
  This means that 0..255 keys can exist for a table. The idea of
  HA_MAX_POSSIBLE_KEY is to ensure that one can use myisamchk & tools on
  a MyISAM table for which one has more keys than MyISAM is normally
  compiled for. If you don't have this, you will get a core dump when
  running myisamchk compiled for 128 keys on a table with 255 keys.
*/

#define HA_MAX_POSSIBLE_KEY         255         /* For myisamchk */
/*
  The following defines can be increased if necessary.
  But beware the dependency of MI_MAX_POSSIBLE_KEY_BUFF and HA_MAX_KEY_LENGTH.
*/

#define HA_MAX_KEY_LENGTH           1000        /* Max length in bytes */
#define HA_MAX_KEY_SEG              16          /* Max segments for key */

#define HA_MAX_POSSIBLE_KEY_BUFF    (HA_MAX_KEY_LENGTH + 24+ 6+6)
#define HA_MAX_KEY_BUFF  (HA_MAX_KEY_LENGTH+HA_MAX_KEY_SEG*6+8+8)

typedef struct st_HA_KEYSEG		/* Key-portion */
{
  CHARSET_INFO *charset;
  uint32 start;				/* Start of key in record */
  uint32 null_pos;			/* position to NULL indicator */
  uint16 bit_pos;                       /* Position to bit part */
  uint16 flag;
  uint16 length;			/* Keylength */
  uint16 language;
  uint8  type;				/* Type of key (for sort) */
  uint8  null_bit;			/* bitmask to test for NULL */
  uint8  bit_start,bit_end;		/* if bit field */
  uint8  bit_length;                    /* Length of bit part */
} HA_KEYSEG;

#define get_key_length(length,key) \
{ if (*(uchar*) (key) != 255) \
    length= (uint) *(uchar*) ((key)++); \
  else \
  { length= mi_uint2korr((key)+1); (key)+=3; } \
}

#define get_key_length_rdonly(length,key) \
{ if (*(uchar*) (key) != 255) \
    length= ((uint) *(uchar*) ((key))); \
  else \
  { length= mi_uint2korr((key)+1); } \
}

#define get_key_pack_length(length,length_pack,key) \
{ if (*(uchar*) (key) != 255) \
  { length= (uint) *(uchar*) ((key)++); length_pack= 1; }\
  else \
  { length=mi_uint2korr((key)+1); (key)+= 3; length_pack= 3; } \
}

#define store_key_length_inc(key,length) \
{ if ((length) < 255) \
  { *(key)++= (length); } \
  else \
  { *(key)=255; mi_int2store((key)+1,(length)); (key)+=3; } \
}

#define size_to_store_key_length(length) ((length) < 255 ? 1 : 3)

#define get_rec_bits(bit_ptr, bit_ofs, bit_len) \
  (((((uint16) (bit_ptr)[1] << 8) | (uint16) (bit_ptr)[0]) >> (bit_ofs)) & \
   ((1 << (bit_len)) - 1))

#define set_rec_bits(bits, bit_ptr, bit_ofs, bit_len) \
{ \
  (bit_ptr)[0]= ((bit_ptr)[0] & ~(((1 << (bit_len)) - 1) << (bit_ofs))) | \
                ((bits) << (bit_ofs)); \
  if ((bit_ofs) + (bit_len) > 8) \
    (bit_ptr)[1]= ((bit_ptr)[1] & ~((1 << ((bit_len) - 8 + (bit_ofs))) - 1)) | \
                  ((bits) >> (8 - (bit_ofs))); \
}

#define clr_rec_bits(bit_ptr, bit_ofs, bit_len) \
  set_rec_bits(0, bit_ptr, bit_ofs, bit_len)

extern int ha_compare_text(CHARSET_INFO *, uchar *, uint, uchar *, uint ,
			   my_bool, my_bool);
extern int ha_key_cmp(register HA_KEYSEG *keyseg, register uchar *a,
		      register uchar *b, uint key_length, uint nextflag,
		      uint *diff_pos);

extern HA_KEYSEG *ha_find_null(HA_KEYSEG *keyseg, uchar *a);
extern void my_handler_error_register(void);
extern void my_handler_error_unregister(void);
/*
  Inside an in-memory data record, memory pointers to pieces of the
  record (like BLOBs) are stored in their native byte order and in
  this amount of bytes.
*/
#define portable_sizeof_char_ptr 8
#ifdef	__cplusplus
}
#endif

#endif /* _my_handler_h */