xpcom/string/public/nsTSubstringTuple.h

   1 //* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim:set ts=2 sw=2 sts=2 et cindent: */
   3 /* ***** BEGIN LICENSE BLOCK *****
   4  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   5  *
   6  * The contents of this file are subject to the Mozilla Public License Version
   7  * 1.1 (the "License"); you may not use this file except in compliance with
   8  * the License. You may obtain a copy of the License at
   9  * http://www.mozilla.org/MPL/
  10  *
  11  * Software distributed under the License is distributed on an "AS IS" basis,
  12  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  13  * for the specific language governing rights and limitations under the
  14  * License.
  15  *
  16  * The Original Code is Mozilla.
  17  *
  18  * The Initial Developer of the Original Code is IBM Corporation.
  19  * Portions created by IBM Corporation are Copyright (C) 2003
  20  * IBM Corporation. All Rights Reserved.
  21  *
  22  * Contributor(s):
  23  *   Darin Fisher <darin@meer.net>
  24  *
  25  * Alternatively, the contents of this file may be used under the terms of
  26  * either the GNU General Public License Version 2 or later (the "GPL"), or
  27  * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
  28  * in which case the provisions of the GPL or the LGPL are applicable instead
  29  * of those above. If you wish to allow use of your version of this file only
  30  * under the terms of either the GPL or the LGPL, and not to allow others to
  31  * use your version of this file under the terms of the MPL, indicate your
  32  * decision by deleting the provisions above and replace them with the notice
  33  * and other provisions required by the GPL or the LGPL. If you do not delete
  34  * the provisions above, a recipient may use your version of this file under
  35  * the terms of any one of the MPL, the GPL or the LGPL.
  36  *
  37  * ***** END LICENSE BLOCK ***** */
  38
  39
  40   /**
  41    * nsTSubstringTuple_CharT
  42    *
  43    * Represents a tuple of string fragments.  Built as a recursive binary tree.
  44    * It is used to implement the concatenation of two or more string objects.
  45    *
  46    * NOTE: This class is a private implementation detail and should never be
  47    * referenced outside the string code.
  48    */
  49 class nsTSubstringTuple_CharT
  50   {
  51     public:
  52
  53       typedef CharT                      char_type;
  54       typedef nsCharTraits<char_type>    char_traits;
  55
  56       typedef nsTSubstringTuple_CharT    self_type;
  57       typedef nsTSubstring_CharT         substring_type;
  58       typedef nsTSubstring_CharT         base_string_type;
  59       typedef PRUint32                   size_type;
  60
  61     public:
  62
  63       nsTSubstringTuple_CharT(const base_string_type* a, const base_string_type* b)
  64         : mHead(nsnull)
  65         , mFragA(a)
  66         , mFragB(b) {}
  67
  68       nsTSubstringTuple_CharT(const self_type& head, const base_string_type* b)
  69         : mHead(&head)
  70         , mFragA(nsnull) // this fragment is ignored when head != nsnull
  71         , mFragB(b) {}
  72
  73         /**
  74          * computes the aggregate string length
  75          */
  76       NS_COM size_type Length() const;
  77
  78         /**
  79          * writes the aggregate string to the given buffer.  bufLen is assumed
  80          * to be equal to or greater than the value returned by the Length()
  81          * method.  the string written to |buf| is not null-terminated.
  82          */
  83       NS_COM void WriteTo(char_type *buf, PRUint32 bufLen) const;
  84
  85         /**
  86          * returns true if this tuple is dependent on (i.e., overlapping with)
  87          * the given char sequence.
  88          */
  89       NS_COM PRBool IsDependentOn(const char_type *start, const char_type *end) const;
  90
  91     private:
  92
  93       const self_type*        mHead;
  94       const base_string_type* mFragA;
  95       const base_string_type* mFragB;
  96   };
  97
  98 inline
  99 const nsTSubstringTuple_CharT
 100 operator+(const nsTSubstringTuple_CharT::base_string_type& a, const nsTSubstringTuple_CharT::base_string_type& b)
 101   {
 102     return nsTSubstringTuple_CharT(&a, &b);
 103   }
 104
 105 inline
 106 const nsTSubstringTuple_CharT
 107 operator+(const nsTSubstringTuple_CharT& head, const nsTSubstringTuple_CharT::base_string_type& b)
 108   {
 109     return nsTSubstringTuple_CharT(head, &b);
 110   }