Drizzled Public API Documentation

variables.cc
1 /* - mode: c; c-basic-offset: 2; indent-tabs-mode: nil; -*-
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3  *
4  * Copyright (C) 2010 Brian Aker
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
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14  * GNU General Public License for more details.
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16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #include <config.h>
22 
23 #include <plugin/session_dictionary/dictionary.h>
24 #include <drizzled/user_var_entry.h>
25 
26 #define LARGEST_USER_VARIABLE_NAME 128
27 
28 namespace session_dictionary {
29 
30 Variables::Variables() :
31  drizzled::plugin::TableFunction("DATA_DICTIONARY", "USER_DEFINED_VARIABLES")
32 {
33  add_field("VARIABLE_NAME", drizzled::plugin::TableFunction::STRING, LARGEST_USER_VARIABLE_NAME, false);
34  add_field("VARIABLE_VALUE", drizzled::plugin::TableFunction::STRING, LARGEST_USER_VARIABLE_NAME, true);
35 }
36 
37 Variables::Generator::Generator(drizzled::Field **arg) :
38  drizzled::plugin::TableFunction::Generator(arg),
39  user_vars(getSession().getUserVariables()),
40  iter(user_vars.begin())
41 {
42 }
43 
44 Variables::Generator::~Generator()
45 {
46 }
47 
48 bool Variables::Generator::populate()
49 {
50  while (iter != user_vars.end())
51  {
52  char buff[LARGEST_USER_VARIABLE_NAME];
53  drizzled::String tmp(buff, sizeof(buff), drizzled::system_charset_info);
54 
55  bool null_value;
56  uint32_t decimals= 4; // arbitrary
57  iter->second->val_str(&null_value, &tmp, decimals);
58 
59 
60  // VARIABLE_NAME
61  push(iter->first);
62 
63  // VARIABLE_VALUE
64  if (null_value)
65  push();
66  else
67  push(tmp.c_str());
68 
69  iter++;
70 
71  return true;
72  }
73 
74  return false;
75 }
76 
77 } /* namespace session_dictionary */