String++.h

   1 /*
   2  * Copyright (c) 2002, Robert Collins.
   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  *     A copy of the GNU General Public License can be found at
  10  *     http://www.gnu.org/
  11  *
  12  * Written by Robert Collins.
  13  *
  14  */
  15
  16 // A String class to replace all the char * manipulation.
  17
  18 #ifndef CINSTALL_STRING_H
  19 #define CINSTALL_STRING_H
  20
  21 #include <stdarg.h>
  22 #include <sys/types.h>
  23 #include <iosfwd>
  24 #include <string>
  25
  26 class io_stream;
  27 class String {
  28   class _data;
  29 public:
  30   // Static members first
  31   inline String();
  32   inline String (String const &);
  33   // We're notperformance bottlenecked.
  34   String (const char *);
  35   String (int const);
  36   String (std::string const &);
  37   inline String & operator = (String const &);
  38   ~String();
  39   // Up to the user to delete[] these.
  40   char * cstr();
  41   char * cstr() const; // may be less optimal
  42   char const * cstr_oneuse() const; // only valid until the next mutator call
  43                               // pretends to be const !!
  44   inline size_t size() const; // number of characters (!= storage size).
  45   size_t find (char) const;
  46   String substr (size_t start = 0, size_t len = -1) const;
  47   // operator == and != can be done if/when we have a 'casesensitive' flag to
  48   // the constructors
  49   // - means this sorts to the left of the parameter
  50   int compare (String const &, size_t const = 0) const;
  51   static int compare (String const &, String const &, size_t const = 0);
  52   int casecompare (String const &, size_t const = 0) const;
  53   static int casecompare (String const &, String const &, size_t const = 0);
  54   static int casecompare (String const, String const);
  55   String &append (String const &);
  56   String &operator += (String const &);
  57   String operator + (String const &) const;
  58   String operator + (char const *) const;
  59   bool operator == (String const &) const;
  60   bool operator == (char const *) const;
  61   struct caseless { bool operator () (String const &s1, String const &s2) const
  62         {
  63           return s1.casecompare (s2) < 0;
  64         }};
  65
  66 private:
  67   class _data {
  68   public:
  69     _data ();
  70     _data (size_t);
  71     _data (_data const &);
  72     ~_data ();
  73     unsigned count; //Invariant: all constructors set to 1;
  74     // For now, char *, but can be TCHAR, or even UNICODE
  75     // when time permits.
  76     unsigned char *theString;
  77     char *cstr; // cached/oneuse Cstr encoded version
  78     size_t length;
  79   } *theData; // Invariant, there is always an
  80   static String absorb (unsigned char *, size_t);
  81 };
  82
  83 std::ostream &
  84 operator << (std::ostream &os, String const &theString);
  85
  86 String::String() : theData (new _data) {}
  87 String::String(String const &aString) : theData (aString.theData)
  88 {
  89   ++theData->count;
  90 }
  91
  92 String &
  93 String::operator= (String const &aString)
  94 {
  95   // Don't touch the order
  96   ++aString.theData->count;
  97   if (--theData->count == 0)
  98     delete theData;
  99   theData = aString.theData;
 100   return *this;
 101 }
 102
 103 size_t
 104 String::size() const
 105 {
 106   return theData->length;
 107 }
 108
 109 #endif // CINSTALL_STRING_H