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
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
|
/* - mode: c; c-basic-offset: 2; indent-tabs-mode: nil; -*-
* vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
*
* Copyright (C) 2009 Sun Microsystems, Inc.
*
* 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "config.h"
#include <plugin/function_engine/cursor.h>
#include <drizzled/session.h>
#include "drizzled/internal/my_sys.h"
#include <unistd.h>
#include <fcntl.h>
#include <string>
using namespace std;
using namespace drizzled;
/*****************************************************************************
** Data Function tables
*****************************************************************************/
FunctionCursor::FunctionCursor(plugin::StorageEngine &engine_arg,
Table &table_arg) :
Cursor(engine_arg, table_arg),
estimate_of_rows(100), // Completely fabricated, I used to use the value 2.
rows_returned(0)
{}
int FunctionCursor::open(const char *name, int, uint32_t)
{
tool= static_cast<Function *>(getEngine())->getFunction(name);
// assert(tool);
record_id= 0;
if (not tool)
return HA_ERR_NO_SUCH_TABLE;
return 0;
}
int FunctionCursor::close(void)
{
tool= NULL;
wipeCache();
return 0;
}
int FunctionCursor::doStartTableScan(bool)
{
rows_returned= 0;
generator= tool->generator(getTable()->getFields());
return 0;
}
int FunctionCursor::rnd_next(unsigned char *)
{
bool more_rows;
ha_statistic_increment(&system_status_var::ha_read_rnd_next_count);
/* Fix bug in the debug logic for field */
for (Field **field= getTable()->getFields() ; *field ; field++)
{
(*field)->setWriteSet();
}
more_rows= generator->sub_populate(getTable()->getShare()->sizeFields());
if (more_rows)
{
return 0;
}
else
{
delete generator;
generator= NULL;
}
rows_returned++;
return more_rows ? 0 : HA_ERR_END_OF_FILE;
}
void FunctionCursor::position(const unsigned char *record)
{
if (row_cache.size() <= record_id * getTable()->getShare()->getRecordLength())
{
row_cache.resize(row_cache.size() + getTable()->getShare()->getRecordLength() * 100); // Hardwired at adding an additional 100 rows of storage
}
memcpy(&row_cache[record_id * getTable()->getShare()->getRecordLength()], record, getTable()->getShare()->getRecordLength());
internal::my_store_ptr(ref, ref_length, record_id);
record_id++;
}
void FunctionCursor::wipeCache()
{
if (rows_returned > estimate_of_rows)
estimate_of_rows= rows_returned;
row_cache.clear();
record_id= 0;
}
int FunctionCursor::extra(enum ha_extra_function operation)
{
switch (operation)
{
case drizzled::HA_EXTRA_CACHE:
break;
case drizzled::HA_EXTRA_NO_CACHE:
break;
case drizzled::HA_EXTRA_RESET_STATE:
wipeCache();
break;
default:
break;
}
return 0;
}
int FunctionCursor::doEndTableScan()
{
delete generator; // Do this in case of an early exit from rnd_next()
return 0;
}
int FunctionCursor::rnd_pos(unsigned char *buf, unsigned char *pos)
{
ha_statistic_increment(&system_status_var::ha_read_rnd_count);
size_t position_id= (size_t)internal::my_get_ptr(pos, ref_length);
assert(position_id * getTable()->getShare()->getRecordLength() < row_cache.size());
memcpy(buf, &row_cache[position_id * getTable()->getShare()->getRecordLength()], getTable()->getShare()->getRecordLength());
return 0;
}
int FunctionCursor::info(uint32_t flag)
{
memset(&stats, 0, sizeof(stats));
if (flag & HA_STATUS_AUTO)
stats.auto_increment_value= 1;
stats.records= estimate_of_rows;
return 0;
}
|