~drizzle-trunk/drizzle/development

1 by brian
clean slate
1
/* Copyright (C) 2002-2006 MySQL AB
2
3
   This library is free software; you can redistribute it and/or
4
   modify it under the terms of the GNU Library General Public
5
   License as published by the Free Software Foundation; version 2
6
   of the License.
7
8
   This library is distributed in the hope that it will be useful,
9
   but WITHOUT ANY WARRANTY; without even the implied warranty of
10
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
11
   Library General Public License for more details.
12
13
   You should have received a copy of the GNU Library General Public
14
   License along with this library; if not, write to the Free
15
   Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
16
   MA 02111-1307, USA */
17
18
#ifndef _my_handler_h
19
#define _my_handler_h
20
21
#include "myisampack.h"
22
#ifdef	__cplusplus
23
extern "C" {
24
#endif
25
26
/*
27
  There is a hard limit for the maximum number of keys as there are only
28
  8 bits in the index file header for the number of keys in a table.
29
  This means that 0..255 keys can exist for a table. The idea of
30
  HA_MAX_POSSIBLE_KEY is to ensure that one can use myisamchk & tools on
31
  a MyISAM table for which one has more keys than MyISAM is normally
32
  compiled for. If you don't have this, you will get a core dump when
33
  running myisamchk compiled for 128 keys on a table with 255 keys.
34
*/
35
36
#define HA_MAX_POSSIBLE_KEY         255         /* For myisamchk */
37
/*
38
  The following defines can be increased if necessary.
39
  But beware the dependency of MI_MAX_POSSIBLE_KEY_BUFF and HA_MAX_KEY_LENGTH.
40
*/
41
42
#define HA_MAX_KEY_LENGTH           1332        /* Max length in bytes */
43
#define HA_MAX_KEY_SEG              16          /* Max segments for key */
44
45
#define HA_MAX_POSSIBLE_KEY_BUFF    (HA_MAX_KEY_LENGTH + 24+ 6+6)
46
#define HA_MAX_KEY_BUFF  (HA_MAX_KEY_LENGTH+HA_MAX_KEY_SEG*6+8+8)
47
48
typedef struct st_HA_KEYSEG		/* Key-portion */
49
{
50
  CHARSET_INFO *charset;
51
  uint32 start;				/* Start of key in record */
52
  uint32 null_pos;			/* position to NULL indicator */
53
  uint16 bit_pos;                       /* Position to bit part */
54
  uint16 flag;
55
  uint16 length;			/* Keylength */
56
  uint8  type;				/* Type of key (for sort) */
57
  uint8  language;
58
  uint8  null_bit;			/* bitmask to test for NULL */
59
  uint8  bit_start,bit_end;		/* if bit field */
60
  uint8  bit_length;                    /* Length of bit part */
61
} HA_KEYSEG;
62
63
#define get_key_length(length,key) \
64
{ if (*(uchar*) (key) != 255) \
65
    length= (uint) *(uchar*) ((key)++); \
66
  else \
67
  { length= mi_uint2korr((key)+1); (key)+=3; } \
68
}
69
70
#define get_key_length_rdonly(length,key) \
71
{ if (*(uchar*) (key) != 255) \
72
    length= ((uint) *(uchar*) ((key))); \
73
  else \
74
  { length= mi_uint2korr((key)+1); } \
75
}
76
77
#define get_key_pack_length(length,length_pack,key) \
78
{ if (*(uchar*) (key) != 255) \
79
  { length= (uint) *(uchar*) ((key)++); length_pack= 1; }\
80
  else \
81
  { length=mi_uint2korr((key)+1); (key)+= 3; length_pack= 3; } \
82
}
83
84
#define store_key_length_inc(key,length) \
85
{ if ((length) < 255) \
86
  { *(key)++= (length); } \
87
  else \
88
  { *(key)=255; mi_int2store((key)+1,(length)); (key)+=3; } \
89
}
90
91
#define size_to_store_key_length(length) ((length) < 255 ? 1 : 3)
92
93
#define get_rec_bits(bit_ptr, bit_ofs, bit_len) \
94
  (((((uint16) (bit_ptr)[1] << 8) | (uint16) (bit_ptr)[0]) >> (bit_ofs)) & \
95
   ((1 << (bit_len)) - 1))
96
97
#define set_rec_bits(bits, bit_ptr, bit_ofs, bit_len) \
98
{ \
99
  (bit_ptr)[0]= ((bit_ptr)[0] & ~(((1 << (bit_len)) - 1) << (bit_ofs))) | \
100
                ((bits) << (bit_ofs)); \
101
  if ((bit_ofs) + (bit_len) > 8) \
102
    (bit_ptr)[1]= ((bit_ptr)[1] & ~((1 << ((bit_len) - 8 + (bit_ofs))) - 1)) | \
103
                  ((bits) >> (8 - (bit_ofs))); \
104
}
105
106
#define clr_rec_bits(bit_ptr, bit_ofs, bit_len) \
107
  set_rec_bits(0, bit_ptr, bit_ofs, bit_len)
108
109
extern int ha_compare_text(CHARSET_INFO *, uchar *, uint, uchar *, uint ,
110
			   my_bool, my_bool);
111
extern int ha_key_cmp(register HA_KEYSEG *keyseg, register uchar *a,
112
		      register uchar *b, uint key_length, uint nextflag,
113
		      uint *diff_pos);
114
115
extern HA_KEYSEG *ha_find_null(HA_KEYSEG *keyseg, uchar *a);
116
extern void my_handler_error_register(void);
117
extern void my_handler_error_unregister(void);
118
/*
119
  Inside an in-memory data record, memory pointers to pieces of the
120
  record (like BLOBs) are stored in their native byte order and in
121
  this amount of bytes.
122
*/
123
#define portable_sizeof_char_ptr 8
124
#ifdef	__cplusplus
125
}
126
#endif
127
128
#endif /* _my_handler_h */