Dogcows Code - chaz/openbox/blob - otk/ustring.hh

   1 // -*- mode: C++; indent-tabs-mode: nil; c-basic-offset: 2; -*-
   2 #ifndef   __ustring_hh
   3 #define   __ustring_hh
   4
   5 /*! @file ustring.hh
   6   @brief Provides a simple UTF-8 encoded string
   7 */
   8
   9 extern "C" {
  10 /*
  11 #ifdef HAVE_STDINT_H
  12 #  include <stdint.h>
  13 #else
  14 #  ifdef HAVE_SYS_TYPES_H
  15 #    include <sys/types.h>
  16 #  endif
  17 #endif
  18 */
  19 }
  20
  21 #include <string>
  22
  23 namespace otk {
  24
  25 /*
  26 #ifdef HAVE_STDINT_H
  27 typedef uint32_t unichar;
  28 #else
  29 typedef u_int32_t unichar;
  30 #endif
  31 */
  32
  33 #ifndef DOXYGEN_IGNORE
  34
  35 //! The number of bytes to skip to find the next character in the string
  36 const char g_utf8_skip[256] = {
  37   1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
  38   1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
  39   1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
  40   1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
  41   1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
  42   1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
  43   2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
  44   3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,6,6,1,1
  45 };
  46
  47 #endif // DOXYGEN_IGNORE
  48
  49 //! The iterator type for ustring
  50 /*!
  51   Note this is not a random access iterator but a bidirectional one, since all
  52   index operations need to iterate over the UTF-8 data.  Use std::advance() to
  53   move to a certain position.
  54   <p>
  55   A writeable iterator isn't provided because:  The number of bytes of the old
  56   UTF-8 character and the new one to write could be different. Therefore, any
  57   write operation would invalidate all other iterators pointing into the same
  58   string.
  59 */
  60 /*
  61 template <class T>
  62 class ustring_Iterator
  63 {
  64 public:
  65   typedef std::bidirectional_iterator_tag   iterator_category;
  66   //typedef unichar                           value_type;
  67   typedef std::string::difference_type      difference_type;
  68   //typedef value_type                        reference;
  69   typedef void                              pointer;
  70
  71   inline ustring_Iterator() {}
  72   inline ustring_Iterator(const ustring_Iterator<std::string::iterator>&
  73                           other) : _pos(other.base()) {}
  74
  75
  76   inline value_type operator*() const {
  77     // get a unicode character from the iterator's position
  78
  79     // get an iterator to the internal string
  80     std::string::const_iterator pos = _pos;
  81
  82     unichar result = static_cast<unsigned char>(*pos);
  83
  84     // if its not a 7-bit ascii character
  85     if((result & 0x80) != 0) {
  86       // len is the number of bytes this character takes up in the string
  87       unsigned char len = g_utf8_skip[result];
  88       result &= 0x7F >> len;
  89
  90       while(--len != 0) {
  91         result <<= 6;
  92         result |= static_cast<unsigned char>(*++pos) & 0x3F;
  93       }
  94     }
  95
  96     return result;
  97   }
  98
  99
 100   inline ustring_Iterator<T> &     operator++() {
 101     pos_ += g_utf8_skip[static_cast<unsigned char>(*pos_)];
 102     return *this;
 103   }
 104   inline ustring_Iterator<T> &     operator--() {
 105     do { --_pos; } while((*_pos & '\xC0') == '\x80');
 106     return *this;
 107   }
 108
 109   explicit inline ustring_Iterator(T pos) : _pos(pos) {}
 110   inline T base() const { return _pos; }
 111
 112 private:
 113   T _pos;
 114 };
 115 */
 116
 117 //! This class provides a simple wrapper to a std::string that can be encoded
 118 //! as UTF-8. The ustring::utf() member specifies if the given string is UTF-8
 119 //! encoded. ustrings default to specifying UTF-8 encoding.
 120 /*!
 121   This class does <b>not</b> handle extended 8-bit ASCII charsets like
 122   ISO-8859-1.
 123   <p>
 124   More info on Unicode and UTF-8 can be found here:
 125   http://www.cl.cam.ac.uk/~mgk25/unicode.html
 126   <p>
 127   This does not subclass std::string, because std::string was intended to be a
 128   final class.  For instance, it does not have a virtual destructor.
 129 */
 130 class ustring {
 131   std::string _string;
 132   bool _utf8;
 133
 134 public:
 135   typedef std::string::size_type                        size_type;
 136   typedef std::string::difference_type                  difference_type;
 137
 138   //typedef unichar                                       value_type;
 139   //typedef unichar &                                     reference;
 140   //typedef const unichar &                               const_reference;
 141
 142   //typedef ustring_Iterator<std::string::iterator>       iterator;
 143   //typedef ustring_Iterator<std::string::const_iterator> const_iterator;
 144
 145   static const size_type npos = std::string::npos;
 146
 147   ustring();
 148   ~ustring();
 149
 150   // make new strings
 151
 152   ustring(const ustring& other);
 153   ustring& operator=(const ustring& other);
 154   ustring(const std::string& src);
 155   ustring(const char* src);
 156
 157   // append to the string
 158
 159   ustring& operator+=(const ustring& src);
 160   ustring& operator+=(const char* src);
 161   ustring& operator+=(char c);
 162
 163   // sizes
 164
 165   ustring::size_type size() const;
 166   ustring::size_type bytes() const;
 167   ustring::size_type capacity() const;
 168   ustring::size_type max_size() const;
 169   bool empty() const;
 170
 171   // erase substrings
 172
 173   void clear();
 174   ustring& erase(size_type i, size_type n=npos);
 175
 176   // change the string's size
 177
 178   void resize(size_type n, char c='\0');
 179
 180   // internal data
 181
 182   const char* data()  const;
 183   const char* c_str() const;
 184
 185   // encoding
 186
 187   bool utf8() const;
 188   void setUtf8(bool utf8);
 189 };
 190
 191 }
 192
 193 #endif // __ustring_hh