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
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
|
/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
/* Read and write key blocks */
#include "myisamdef.h"
#ifdef __WIN__
#include <errno.h>
#endif
/* Fetch a key-page in memory */
uchar *_mi_fetch_keypage(register MI_INFO *info, MI_KEYDEF *keyinfo,
my_off_t page, uchar *buff, int return_buffer)
{
uchar *tmp;
uint page_size;
tmp=(uchar*) key_cache_read(info->s->kfile,page,(byte*) buff,
(uint) keyinfo->block_length,
(uint) keyinfo->block_length,
return_buffer);
if (tmp == info->buff)
info->buff_used=1;
else if (!tmp)
{
DBUG_PRINT("error",("Got errno: %d from key_cache_read",my_errno));
info->last_keypage=HA_OFFSET_ERROR;
my_errno=HA_ERR_CRASHED;
return 0;
}
info->last_keypage=page;
page_size=mi_getint(tmp);
if (page_size < 4 || page_size > keyinfo->block_length)
{
DBUG_PRINT("error",("page %lu had wrong page length: %u",
(ulong) page, page_size));
info->last_keypage = HA_OFFSET_ERROR;
my_errno = HA_ERR_CRASHED;
tmp = 0;
}
return tmp;
} /* _mi_fetch_keypage */
/* Write a key-page on disk */
int _mi_write_keypage(register MI_INFO *info, register MI_KEYDEF *keyinfo,
my_off_t page, uchar *buff)
{
reg3 uint length;
#ifndef FAST /* Safety check */
if (page < info->s->base.keystart ||
page+keyinfo->block_length > info->state->key_file_length ||
page & (myisam_block_size-1))
{
DBUG_PRINT("error",("Trying to write outside key region: %lu",
(long) page));
my_errno=EINVAL;
return(-1);
}
DBUG_PRINT("page",("write page at: %lu",(long) page,buff));
DBUG_DUMP("buff",(byte*) buff,mi_getint(buff));
#endif
if ((length=keyinfo->block_length) > IO_SIZE*2 &&
info->state->key_file_length != page+length)
length= ((mi_getint(buff)+IO_SIZE-1) & (uint) ~(IO_SIZE-1));
#ifdef HAVE_purify
{
length=mi_getint(buff);
bzero((byte*) buff+length,keyinfo->block_length-length);
length=keyinfo->block_length;
}
#endif
return (key_cache_write(info->s->kfile,page,(byte*) buff,length,
(uint) keyinfo->block_length,
(int) ((info->lock_type != F_UNLCK) ||
info->s->delay_key_write)));
} /* mi_write_keypage */
/* Remove page from disk */
int _mi_dispose(register MI_INFO *info, MI_KEYDEF *keyinfo, my_off_t pos)
{
my_off_t old_link;
char buff[8];
DBUG_ENTER("_mi_dispose");
old_link=info->s->state.key_del[keyinfo->block_size];
info->s->state.key_del[keyinfo->block_size]=pos;
mi_sizestore(buff,old_link);
DBUG_RETURN(key_cache_write(info->s->kfile,pos,buff,
sizeof(buff),
(uint) keyinfo->block_length,
(int) (info->lock_type != F_UNLCK)));
} /* _mi_dispose */
/* Make new page on disk */
my_off_t _mi_new(register MI_INFO *info, MI_KEYDEF *keyinfo)
{
my_off_t pos;
char buff[8];
DBUG_ENTER("_mi_new");
if ((pos=info->s->state.key_del[keyinfo->block_size]) == HA_OFFSET_ERROR)
{
if (info->state->key_file_length >=
info->s->base.max_key_file_length - keyinfo->block_length)
{
my_errno=HA_ERR_INDEX_FILE_FULL;
DBUG_RETURN(HA_OFFSET_ERROR);
}
pos=info->state->key_file_length;
info->state->key_file_length+= keyinfo->block_length;
}
else
{
if (!key_cache_read(info->s->kfile,pos,
buff,
(uint) sizeof(buff),
(uint) keyinfo->block_length,0))
pos= HA_OFFSET_ERROR;
else
info->s->state.key_del[keyinfo->block_size]=mi_sizekorr(buff);
}
DBUG_PRINT("exit",("Pos: %d",pos));
DBUG_RETURN(pos);
} /* _mi_new */
|
