Drizzled Public API Documentation

boolean.cc
1 /* - mode: c++ c-basic-offset: 2; indent-tabs-mode: nil; -*-
2  * vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
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
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14  * GNU General Public License for more details.
15  *
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 <drizzled/error.h>
24 #include <drizzled/function/cast/boolean.h>
25 #include <drizzled/lex_string.h>
26 #include <drizzled/type/boolean.h>
27 
28 namespace drizzled {
29 namespace function {
30 namespace cast {
31 
33 {
34  str->append(STRING_WITH_LEN("cast("));
35  args[0]->print(str);
36  str->append(STRING_WITH_LEN(" as boolean)"));
37 }
38 
40 {
41  switch (args[0]->result_type())
42  {
43  case STRING_RESULT:
44  {
45  drizzled::String _res, *res;
46 
47  if (not (res= args[0]->val_str(&_res)))
48  {
49  null_value= true;
50  break;
51  }
52  null_value= false;
53 
54  bool result;
55  if (not type::convert(result, *res))
56  {
57  my_error(ER_INVALID_CAST_TO_BOOLEAN, MYF(0), res->c_ptr());
58  }
59 
60  return evaluate(result, value);
61  }
62 
63  case REAL_RESULT:
64  case ROW_RESULT:
65  case DECIMAL_RESULT:
66  case INT_RESULT:
67  {
68  bool tmp= args[0]->val_bool();
69  null_value=args[0]->null_value;
70 
71  return evaluate(tmp, value);
72  }
73  }
74 
75  // We should never reach this
76  return evaluate(false, value);
77 }
78 
79 String *Boolean::evaluate(const bool &result, String *val_buffer)
80 {
81  val_buffer->alloc(5 * my_charset_bin.mbmaxlen);
82  char *buffer= val_buffer->c_ptr();
83 
84  if (result)
85  {
86  memcpy(buffer, "TRUE", 4);
87  val_buffer->length(4);
88  }
89  else
90  {
91  memcpy(buffer, "FALSE", 5);
92  val_buffer->length(5);
93  }
94 
95  return val_buffer;
96 }
97 
98 } // namespace cast
99 } // namespace function
100 } // namespace drizzled
bool null_value
Definition: item.h:122
virtual bool val_bool()
Definition: item.cc:95
virtual void print(String *str)
Definition: boolean.cc:32
virtual void print(String *str)
Definition: item.cc:362
drizzled::String * val_str(drizzled::String *value)
Definition: boolean.cc:39