1 /*
   2  * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #ifndef SHARE_VM_UTILITIES_UTF8_HPP
  26 #define SHARE_VM_UTILITIES_UTF8_HPP
  27 
  28 #include "memory/allocation.hpp"
  29 #include "utilities/top.hpp"
  30 
  31 // Low-level interface for UTF8 strings
  32 
  33 class UTF8 : AllStatic {
  34  public:
  35   // returns the unicode length of a 0-terminated uft8 string
  36   static int unicode_length(const char* uft8_str);
  37 
  38   // returns the unicode length of a non-0-terminated uft8 string
  39   static int unicode_length(const char* uft8_str, int len);
  40 
  41   // converts a uft8 string to a unicode string
  42   static void convert_to_unicode(const char* utf8_str, jchar* unicode_buffer, int unicode_length);
  43 
  44   // decodes the current utf8 character, stores the result in value,
  45   // and returns the end of the current uft8 chararacter.
  46   static char* next(const char* str, jchar* value);
  47 
  48   // decodes the current utf8 character, gets the supplementary character instead of
  49   // the surrogate pair when seeing a supplementary character in string,
  50   // stores the result in value, and returns the end of the current uft8 chararacter.
  51   static char* next_character(const char* str, jint* value);
  52 
  53   // Utility methods
  54   static jbyte* strrchr(jbyte* base, int length, jbyte c);
  55   static bool   equal(jbyte* base1, int length1, jbyte* base2, int length2);
  56   static bool   is_supplementary_character(const unsigned char* str);
  57   static jint   get_supplementary_character(const unsigned char* str);
  58 };
  59 
  60 
  61 // Low-level interface for UNICODE strings
  62 
  63 // A unicode string represents a string in the UTF-16 format in which supplementary
  64 // characters are represented by surrogate pairs. Index values refer to char code
  65 // units, so a supplementary character uses two positions in a unicode string.
  66 
  67 class UNICODE : AllStatic {
  68  public:
  69   // returns the utf8 size of a unicode character
  70   static int utf8_size(jchar c);
  71 
  72   // returns the utf8 length of a unicode string
  73   static int utf8_length(jchar* base, int length);
  74 
  75   // converts a unicode string to utf8 string
  76   static void convert_to_utf8(const jchar* base, int length, char* utf8_buffer);
  77 
  78   // converts a unicode string to a utf8 string; result is allocated
  79   // in resource area unless a buffer is provided.
  80   static char* as_utf8(jchar* base, int length);
  81   static char* as_utf8(jchar* base, int length, char* buf, int buflen);
  82 };
  83 
  84 #endif // SHARE_VM_UTILITIES_UTF8_HPP