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
|
/* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-
* vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
*
* Copyright (C) 2008 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; version 2 of the License.
*
* 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
*/
#ifndef DRIZZLED_SELECT_SEND_H
#define DRIZZLED_SELECT_SEND_H
#include <drizzled/plugin/client.h>
#include <drizzled/plugin/query_cache.h>
#include <drizzled/plugin/transactional_storage_engine.h>
namespace drizzled
{
class select_send :public select_result {
/**
True if we have sent result set metadata to the client.
In this case the client always expects us to end the result
set with an eof or error packet
*/
bool is_result_set_started;
public:
select_send() :is_result_set_started(false) {}
bool send_eof()
{
/*
We may be passing the control from mysqld to the client: release the
InnoDB adaptive hash S-latch to avoid thread deadlocks if it was reserved
by session
*/
plugin::TransactionalStorageEngine::releaseTemporaryLatches(session);
/* Unlock tables before sending packet to gain some speed */
if (session->lock)
{
session->unlockTables(session->lock);
session->lock= 0;
}
session->my_eof();
is_result_set_started= 0;
return false;
}
bool send_fields(List<Item> &list)
{
bool res;
if (! (res= session->getClient()->sendFields(&list)))
is_result_set_started= 1;
return res;
}
void abort()
{
return;
}
/**
Cleanup an instance of this class for re-use
at next execution of a prepared statement/
stored procedure statement.
*/
virtual void cleanup()
{
is_result_set_started= false;
}
/* Send data to client. Returns 0 if ok */
bool send_data(List<Item> &items)
{
if (unit->offset_limit_cnt)
{ // using limit offset,count
unit->offset_limit_cnt--;
return false;
}
/*
We may be passing the control from mysqld to the client: release the
InnoDB adaptive hash S-latch to avoid thread deadlocks if it was reserved
by session
*/
plugin::TransactionalStorageEngine::releaseTemporaryLatches(session);
List_iterator_fast<Item> li(items);
char buff[MAX_FIELD_WIDTH];
String buffer(buff, sizeof(buff), &my_charset_bin);
Item *item;
while ((item=li++))
{
if (item->send(session->getClient(), &buffer))
{
my_message(ER_OUT_OF_RESOURCES, ER(ER_OUT_OF_RESOURCES), MYF(0));
break;
}
}
/* Insert this record to the Resultset into the cache */
if (session->query_cache_key != "" && session->getResultsetMessage() != NULL)
plugin::QueryCache::insertRecord(session, items);
session->sent_row_count++;
if (session->is_error())
return true;
return session->getClient()->flush();
}
};
} /* namespace drizzled */
#endif /* DRIZZLED_SELECT_SEND_H */
|