libs/pbd/whitespace.cc

   1 /*
   2     Copyright (C) 2000-2007 Paul Davis
   3
   4     This program is free software; you can redistribute it and/or modify
   5     it under the terms of the GNU General Public License as published by
   6     the Free Software Foundation; either version 2 of the License, or
   7     (at your option) any later version.
   8
   9     This program is distributed in the hope that it will be useful,
  10     but WITHOUT ANY WARRANTY; without even the implied warranty of
  11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12     GNU General Public License for more details.
  13
  14     You should have received a copy of the GNU General Public License
  15     along with this program; if not, write to the Free Software
  16     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  17
  18 */
  19
  20 #include "pbd/whitespace.h"
  21
  22 using namespace std;
  23
  24 namespace PBD {
  25
  26 void
  27 strip_whitespace_edges (string& str)
  28 {
  29     string::size_type i;
  30     string::size_type len;
  31     string::size_type s = 0;
  32
  33     len = str.length();
  34
  35     if (len == 1) {
  36             return;
  37     }
  38
  39     /* strip front */
  40
  41     for (i = 0; i < len; ++i) {
  42         if (!isspace (str[i])) {
  43             break;
  44         }
  45     }
  46
  47     if (i == len) {
  48             /* it's all whitespace, not much we can do */
  49                 str = "";
  50             return;
  51     }
  52
  53     /* strip back */
  54
  55     if (len > 1) {
  56
  57             s = i;
  58             i = len - 1;
  59
  60             if (s == i) {
  61                     return;
  62             }
  63
  64             do {
  65                     if (!isspace (str[i]) || i == 0) {
  66                             break;
  67                     }
  68
  69                     --i;
  70
  71             } while (true);
  72
  73             str = str.substr (s, (i - s) + 1);
  74
  75     } else {
  76             str = str.substr (s);
  77     }
  78 }
  79
  80 } // namespace PBD