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
  24 class io_stream;
  25 class String {
  26   class _data;
  27 public:
  28   // Static members first
  29   static String concat (const char *s, ...);
  30   static String vconcat (const char *, va_list);
  31
  32   inline String();
  33   inline String (String const &);
  34   // We're notperformance bottlenecked.
  35   String (const char *);
  36   inline String & operator = (String const &);
  37   ~String();
  38   // Up to the user to delete[] these.
  39   char * cstr();
  40   char * cstr() const; // may be less optimal
  41   char const * cstr_oneuse() const; // only valid until the next mutator call
  42                               // pretends to be const !!
  43   inline size_t size() const; // number of characters (!= storage size).
  44   size_t find (char) const;
  45   // operator == and != can be done if/when we have a 'casesensitive' flag to
  46   // the constructors
  47   // - means this sorts to the left of the parameter
  48   int compare (String const &, size_t const = 0) const;
  49   static int compare (String const &, String const &, size_t const = 0);
  50   int casecompare (String const &, size_t const = 0) const;
  51   static int casecompare (String const &, String const &, size_t const = 0);
  52   static int casecompare (String const, String const);
  53   String &append (String const &);
  54   String &operator += (String const &);
  55   String operator + (String const &) const;
  56   String operator + (char const *) const;
  57   bool operator == (String const &) const;
  58   bool operator == (char const *) const;
  59
  60 private:
  61   class _data {
  62   public:
  63     _data ();
  64     _data (size_t);
  65     _data (_data const &);
  66     ~_data ();
  67     unsigned count; //Invariant: all constructors set to 1;
  68     // For now, char *, but can be TCHAR, or even UNICODE
  69     // when time permits.
  70     unsigned char *theString;
  71     char *cstr; // cached/oneuse Cstr encoded version
  72     size_t length;
  73   } *theData; // Invariant, there is always an
  74   static String absorb (unsigned char *, size_t);
  75 };
  76
  77 String::String() : theData (new _data) {}
  78 String::String(String const &aString) : theData (aString.theData)
  79 {
  80   ++theData->count;
  81 }
  82
  83 String &
  84 String::operator= (String const &aString)
  85 {
  86   // Don't touch the order
  87   ++aString.theData->count;
  88   if (--theData->count == 0)
  89     delete theData;
  90   theData = aString.theData;
  91   return *this;
  92 }
  93
  94 size_t
  95 String::size() const
  96 {
  97   return theData->length;
  98 }
  99
 100 #endif // CINSTALL_STRING_H