Drizzled Public API Documentation

right.cc
00001 /* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-
00002  *  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
00003  *
00004  *  Copyright (C) 2008 Sun Microsystems, Inc.
00005  *
00006  *  This program is free software; you can redistribute it and/or modify
00007  *  it under the terms of the GNU General Public License as published by
00008  *  the Free Software Foundation; version 2 of the License.
00009  *
00010  *  This program is distributed in the hope that it will be useful,
00011  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
00012  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00013  *  GNU General Public License for more details.
00014  *
00015  *  You should have received a copy of the GNU General Public License
00016  *  along with this program; if not, write to the Free Software
00017  *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
00018  */
00019 
00020 #include <config.h>
00021 
00022 #include <drizzled/function/str/right.h>
00023 
00024 namespace drizzled
00025 {
00026 
00027 String *Item_func_right::val_str(String *str)
00028 {
00029   assert(fixed == 1);
00030   String *res= args[0]->val_str(str);
00031   /* must be int64_t to avoid truncation */
00032   int64_t length= args[1]->val_int();
00033 
00034   if ((null_value=(args[0]->null_value || args[1]->null_value)))
00035     return 0;
00036 
00037   /* if "unsigned_flag" is set, we have a *huge* positive number. */
00038   if ((length <= 0) && (!args[1]->unsigned_flag))
00039     return &my_empty_string;
00040 
00041   if (res->length() <= (uint64_t) length)
00042     return res;
00043 
00044   uint32_t start=res->numchars();
00045   if (start <= (uint) length)
00046     return res;
00047   start=res->charpos(start - (uint) length);
00048   tmp_value.set(*res,start,res->length()-start);
00049   return &tmp_value;
00050 }
00051 
00052 void Item_func_right::fix_length_and_dec()
00053 {
00054   collation.set(args[0]->collation);
00055   left_right_max_length();
00056 }
00057 
00058 } /* namespace drizzled */