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
|
/*
Copyright (c) 2014, 2025, Oracle and/or its affiliates.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License, version 2.0,
as published by the Free Software Foundation.
This program is designed to work with certain software (including
but not limited to OpenSSL) that is licensed under separate terms,
as designated in a particular file or component or in included license
documentation. The authors of MySQL hereby grant you an additional
permission to link the program and your derivative works with the
separately licensed software that they have either included with
the program or referenced in the documentation.
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, version 2.0, 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 "client/base/show_variable_query_extractor.h"
#include <functional>
using namespace Mysql::Tools::Base;
using std::string;
using std::vector;
using std::placeholders::_1;
Show_variable_query_extractor::Show_variable_query_extractor()
: m_exists(false) {}
int64 Show_variable_query_extractor::extract_variable(
const Mysql_query_runner::Row &result_row) {
this->m_extracted_variable = result_row[0];
this->m_exists = true;
Mysql_query_runner::cleanup_result(result_row);
return 0;
}
int64 Show_variable_query_extractor::get_variable_value(
Mysql_query_runner *query_runner_to_copy, string variable, string &value,
bool &exists) {
Show_variable_query_extractor extractor;
Mysql_query_runner query_runner_to_use(*query_runner_to_copy);
std::function<int64(const Mysql_query_runner::Row &)> result_cb = std::bind(
&Show_variable_query_extractor::extract_variable, &extractor, _1);
query_runner_to_use.add_result_callback(&result_cb);
/*
Note: Because MySQL uses the C escape syntax in strings (for example, '\n'
to represent newline), you must double any '\' that you use in your LIKE
strings. For example, to search for '\n', specify it as '\\n'.To search for
'\', specify it as '\\\\' (the backslashes are stripped once by the parser
and another time when the pattern match is done, leaving a single backslash
to be matched).
Example: "t\1" = > "t\\\\1"
*/
string quoted_variable;
for (size_t i = 0; i < variable.size(); i++) {
if (variable[i] == '\\') {
quoted_variable.append(3, '\\');
} else if (variable[i] == '\'' || variable[i] == '_' ||
variable[i] == '%') {
quoted_variable += '\\';
}
quoted_variable += variable[i];
}
query_runner_to_use.run_query("SELECT @@global." + quoted_variable);
value = extractor.m_extracted_variable;
exists = extractor.m_exists;
return 0;
}
|
