1/*
2 Copyright (c) 2000, 2010, Oracle and/or its affiliates
3
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; version 2 of the License.
7
8 This program 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
11 GNU General Public License for more details.
12
13 You should have received a copy of the GNU General Public License
14 along with this program; if not, write to the Free Software
15 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
16
17/* Read and write key blocks */
18
19#include "myisamdef.h"
20
21 /* Fetch a key-page in memory */
22
23uchar *_mi_fetch_keypage(register MI_INFO *info, MI_KEYDEF *keyinfo,
24 my_off_t page, int level,
25 uchar *buff, int return_buffer)
26{
27 uchar *tmp;
28 uint page_size;
29 DBUG_ENTER("_mi_fetch_keypage");
30 DBUG_PRINT("enter",("page: %ld", (long) page));
31
32 tmp=(uchar*) key_cache_read(info->s->key_cache,
33 info->s->kfile, page, level, (uchar*) buff,
34 (uint) keyinfo->block_length,
35 (uint) keyinfo->block_length,
36 return_buffer);
37 if (tmp == info->buff)
38 info->buff_used=1;
39 else if (!tmp)
40 {
41 DBUG_PRINT("error",("Got errno: %d from key_cache_read",my_errno));
42 info->last_keypage=HA_OFFSET_ERROR;
43 mi_print_error(info->s, HA_ERR_CRASHED);
44 my_errno=HA_ERR_CRASHED;
45 DBUG_RETURN(0);
46 }
47 info->last_keypage=page;
48 page_size=mi_getint(tmp);
49 if (page_size < 4 || page_size > keyinfo->block_length)
50 {
51 DBUG_PRINT("error",("page %lu had wrong page length: %u",
52 (ulong) page, page_size));
53 DBUG_DUMP("page", tmp, keyinfo->block_length);
54 info->last_keypage = HA_OFFSET_ERROR;
55 mi_print_error(info->s, HA_ERR_CRASHED);
56 my_errno = HA_ERR_CRASHED;
57 tmp = 0;
58 }
59 DBUG_RETURN(tmp);
60} /* _mi_fetch_keypage */
61
62
63 /* Write a key-page on disk */
64
65int _mi_write_keypage(register MI_INFO *info, register MI_KEYDEF *keyinfo,
66 my_off_t page, int level, uchar *buff)
67{
68 reg3 uint length;
69 DBUG_ENTER("_mi_write_keypage");
70
71#ifndef FAST /* Safety check */
72 if (page < info->s->base.keystart ||
73 page+keyinfo->block_length > info->state->key_file_length ||
74 (page & (MI_MIN_KEY_BLOCK_LENGTH-1)))
75 {
76 DBUG_PRINT("error",("Trying to write inside key status region: key_start: %lu length: %lu page: %lu",
77 (long) info->s->base.keystart,
78 (long) info->state->key_file_length,
79 (long) page));
80 my_errno=EINVAL;
81 DBUG_RETURN((-1));
82 }
83 DBUG_PRINT("page",("write page at: %lu",(long) page));
84 DBUG_DUMP("buff",(uchar*) buff,mi_getint(buff));
85#endif
86
87 if ((length=keyinfo->block_length) > IO_SIZE*2 &&
88 info->state->key_file_length != page+length)
89 length= ((mi_getint(buff)+IO_SIZE-1) & (uint) ~(IO_SIZE-1));
90 DBUG_RETURN((key_cache_write(info->s->key_cache,
91 info->s->kfile, &info->s->dirty_part_map,
92 page, level, (uchar*) buff, length,
93 (uint) keyinfo->block_length,
94 (int) ((info->lock_type != F_UNLCK) ||
95 info->s->delay_key_write))));
96} /* mi_write_keypage */
97
98
99 /* Remove page from disk */
100
101int _mi_dispose(register MI_INFO *info, MI_KEYDEF *keyinfo, my_off_t pos,
102 int level)
103{
104 my_off_t old_link;
105 uchar buff[8];
106 DBUG_ENTER("_mi_dispose");
107 DBUG_PRINT("enter",("pos: %ld", (long) pos));
108
109 old_link= info->s->state.key_del[keyinfo->block_size_index];
110 info->s->state.key_del[keyinfo->block_size_index]= pos;
111 mi_sizestore(buff,old_link);
112 info->s->state.changed|= STATE_NOT_SORTED_PAGES;
113 DBUG_RETURN(key_cache_write(info->s->key_cache,
114 info->s->kfile, &info->s->dirty_part_map,
115 pos , level, buff,
116 sizeof(buff),
117 (uint) keyinfo->block_length,
118 (int) (info->lock_type != F_UNLCK)));
119} /* _mi_dispose */
120
121
122 /* Make new page on disk */
123
124my_off_t _mi_new(register MI_INFO *info, MI_KEYDEF *keyinfo, int level)
125{
126 my_off_t pos;
127 uchar buff[8];
128 DBUG_ENTER("_mi_new");
129
130 if ((pos= info->s->state.key_del[keyinfo->block_size_index]) ==
131 HA_OFFSET_ERROR)
132 {
133 if (info->state->key_file_length >=
134 info->s->base.max_key_file_length - keyinfo->block_length)
135 {
136 my_errno=HA_ERR_INDEX_FILE_FULL;
137 DBUG_RETURN(HA_OFFSET_ERROR);
138 }
139 pos=info->state->key_file_length;
140 info->state->key_file_length+= keyinfo->block_length;
141 }
142 else
143 {
144 if (!key_cache_read(info->s->key_cache,
145 info->s->kfile, pos, level,
146 buff,
147 (uint) sizeof(buff),
148 (uint) keyinfo->block_length,0))
149 pos= HA_OFFSET_ERROR;
150 else
151 info->s->state.key_del[keyinfo->block_size_index]= mi_sizekorr(buff);
152 }
153 info->s->state.changed|= STATE_NOT_SORTED_PAGES;
154 DBUG_PRINT("exit",("Pos: %ld",(long) pos));
155 DBUG_RETURN(pos);
156} /* _mi_new */
157