Drizzled Public API Documentation

hp_clear.cc
1 /* Copyright (C) 2000-2002, 2004, 2006 MySQL AB
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 as published by
5  the Free Software Foundation; version 2 of the License.
6 
7  This program is distributed in the hope that it will be useful,
8  but WITHOUT ANY WARRANTY; without even the implied warranty of
9  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10  GNU General Public License for more details.
11 
12  You should have received a copy of the GNU General Public License
13  along with this program; if not, write to the Free Software
14  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
15 
16 /*
17  remove all records from database
18  Identical as hp_create() and hp_open() but used HP_SHARE* instead of name and
19  database remains open.
20 */
21 
22 #include <drizzled/error_t.h>
23 #include "heap_priv.h"
24 
25 using namespace drizzled;
26 
27 static void hp_clear_keys(HP_SHARE *info);
28 
29 void heap_clear(HP_INFO *info)
30 {
31  hp_clear(info->getShare());
32 }
33 
34 void hp_clear(HP_SHARE *info)
35 {
36  hp_clear_dataspace(&info->recordspace);
37  hp_clear_keys(info);
38  info->records= 0;
39  info->blength=1;
40  info->changed=0;
41  return;
42 }
43 
44 /*
45  Clear all keys.
46 
47  SYNOPSIS
48  hp_clear_keys()
49  info A pointer to the heap storage engine HP_SHARE struct.
50 
51  DESCRIPTION
52  Delete all trees of all indexes and leave them empty.
53 
54  RETURN
55  void
56 */
57 
58 static void hp_clear_keys(HP_SHARE *info)
59 {
60  for (uint32_t key=0 ; key < info->keys ; key++)
61  {
62  HP_KEYDEF *keyinfo = info->keydef + key;
63  {
64  HP_BLOCK *block= &keyinfo->block;
65  if (block->levels)
66  hp_free_level(block,block->levels,block->root,(unsigned char*) 0);
67  block->levels=0;
68  block->last_allocated=0;
69  keyinfo->hash_buckets= 0;
70  }
71  }
72  info->index_length=0;
73 }
74 
75 
76 /*
77  Disable all indexes.
78 
79  SYNOPSIS
80  heap_disable_indexes()
81  info A pointer to the heap storage engine HP_INFO struct.
82 
83  DESCRIPTION
84  Disable and clear (remove contents of) all indexes.
85 
86  RETURN
87  0 ok
88 */
89 
90 int heap_disable_indexes(HP_INFO *info)
91 {
92  HP_SHARE *share= info->getShare();
93 
94  if (share->keys)
95  {
96  hp_clear_keys(share);
97  share->currently_disabled_keys= share->keys;
98  share->keys= 0;
99  }
100  return 0;
101 }
102 
103 
104 /*
105  Enable all indexes
106 
107  SYNOPSIS
108  heap_enable_indexes()
109  info A pointer to the heap storage engine HP_INFO struct.
110 
111  DESCRIPTION
112  Enable all indexes. The indexes might have been disabled
113  by heap_disable_index() before.
114  The function works only if both data and indexes are empty,
115  since the heap storage engine cannot repair the indexes.
116  To be sure, call handler::delete_all_rows() before.
117 
118  RETURN
119  0 ok
120  HA_ERR_CRASHED data or index is non-empty.
121 */
122 
123 int heap_enable_indexes(HP_INFO *info)
124 {
125  int error= 0;
126  HP_SHARE *share= info->getShare();
127 
128  if (share->recordspace.total_data_length || share->index_length)
129  error= HA_ERR_CRASHED;
130  else
131  if (share->currently_disabled_keys)
132  {
133  share->keys= share->currently_disabled_keys;
134  share->currently_disabled_keys= 0;
135  }
136  return error;
137 }
138 
139 
140 /*
141  Test if indexes are disabled.
142 
143  SYNOPSIS
144  heap_indexes_are_disabled()
145  info A pointer to the heap storage engine HP_INFO struct.
146 
147  DESCRIPTION
148  Test if indexes are disabled.
149 
150  RETURN
151  0 indexes are not disabled
152  1 all indexes are disabled
153  [2 non-unique indexes are disabled - NOT YET IMPLEMENTED]
154 */
155 
156 int heap_indexes_are_disabled(HP_INFO *info)
157 {
158  HP_SHARE *share= info->getShare();
159 
160  return (! share->keys && share->currently_disabled_keys);
161 }
TODO: Rename this file - func.h is stupid.