Drizzled Public API Documentation

left.cc
1 /* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-
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3  *
4  * Copyright (C) 2008 Sun Microsystems, Inc.
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8  * the Free Software Foundation; version 2 of the License.
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12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13  * GNU General Public License for more details.
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17  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18  */
19 
20 #include <config.h>
21 
22 #include <drizzled/function/str/left.h>
23 
24 namespace drizzled
25 {
26 
28 {
29  assert(fixed == 1);
30  String *res= args[0]->val_str(str);
31 
32  /* must be int64_t to avoid truncation */
33  int64_t length= args[1]->val_int();
34  uint32_t char_pos;
35 
36  if ((null_value=(args[0]->null_value || args[1]->null_value)))
37  return 0;
38 
39  /* if "unsigned_flag" is set, we have a *huge* positive number. */
40  if ((length <= 0) && (!args[1]->unsigned_flag))
41  return &my_empty_string;
42 
43  if ((res->length() <= (uint64_t) length) ||
44  (res->length() <= (char_pos= res->charpos((int) length))))
45  return res;
46 
47  tmp_value.set(*res, 0, char_pos);
48  return &tmp_value;
49 }
50 
51 void Item_func_left::fix_length_and_dec()
52 {
53  collation.set(args[0]->collation);
54  left_right_max_length();
55 }
56 
57 } /* namespace drizzled */
virtual int64_t val_int()=0
bool fixed
Definition: item.h:120
bool null_value
Definition: item.h:122
String * val_str(String *)
Definition: left.cc:27
virtual String * val_str(String *str)=0