src/iconv.h

   1 ///
   2 /// \file       iconv.h
   3 ///             iconv wrapper class, and pluggable interface for records
   4 ///
   5
   6 /*
   7     Copyright (C) 2008-2009, Net Direct Inc. (http://www.netdirect.ca/)
   8
   9     This program is free software; you can redistribute it and/or modify
  10     it under the terms of the GNU General Public License as published by
  11     the Free Software Foundation; either version 2 of the License, or
  12     (at your option) any later version.
  13
  14     This program is distributed in the hope that it will be useful,
  15     but WITHOUT ANY WARRANTY; without even the implied warranty of
  16     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  17
  18     See the GNU General Public License in the COPYING file at the
  19     root directory of this project for more details.
  20 */
  21
  22 #ifndef __BARRY_ICONV_H__
  23 #define __BARRY_ICONV_H__
  24
  25 #include "dll.h"
  26 #include "data.h"
  27 #include <iconv.h>
  28 #include <string>
  29
  30 namespace Barry {
  31
  32 class IConverter;
  33
  34 //
  35 // IConvHandle class
  36 //
  37 /// Wrapper class for a two-way iconv_t handle pair.  Automatically
  38 /// handles closing in the destructor.
  39 //
  40 class BXEXPORT IConvHandle
  41 {
  42         friend class IConverter;
  43
  44         iconv_t m_handle;
  45
  46 private:
  47         // private constructor, used only by IConverter
  48         IConvHandle(const char *fromcode, const char *tocode);
  49
  50 public:
  51         // custom conversions from any to IConverter's 'tocode'
  52         IConvHandle(const char *fromcode, const IConverter &ic);
  53         // custom conversions from IConverter's 'tocode' to any
  54         IConvHandle(const IConverter &ic, const char *tocode);
  55         ~IConvHandle();
  56 };
  57
  58 //
  59 // IConverter
  60 //
  61 /// Main charset conversion class, primarily focused on converting
  62 /// between the Blackberry charset and an application-specified one.
  63 /// Additional conversions are possible through custom IConvHandle,
  64 /// but the goal of this class design is to deal with _one_
  65 /// application defined charset, and provide a means to convert
  66 /// to/from that charset to/from any other charset needed by
  67 /// the Blackberry.
  68 ///
  69 /// By default, this class assumes the Blackberry's charset is
  70 /// WINDOWS-1252, but some data, such as SMS message bodies, can have
  71 /// custom charsets as specified by the records.  To convert from
  72 /// such a custom charset, use:
  73 ///
  74 ///      // application sets up IConverter
  75 ///      IConverter ic("UTF-8");
  76 ///
  77 ///      // somewhere in the library, needing to convert
  78 ///      // from UCS2 to whatever the application selected
  79 ///      IConvHandle ucs2("UCS2", ic);
  80 ///      application_string = ic.Convert(ucs2, ucs2_string_data);
  81 ///
  82 ///      // and to convert back...
  83 ///      IConvHandle ucs2_reverse(ic, "UCS2");
  84 ///      ucs2_string = ic.Convert(ucs2_reverse, application_string_data);
  85 ///
  86 class BXEXPORT IConverter
  87 {
  88         friend class IConvHandle;
  89
  90         IConvHandle m_from;
  91         IConvHandle m_to;
  92         std::string m_tocode;
  93
  94         // internal buffer for fast conversions
  95         mutable Data m_buffer;
  96
  97         bool m_throw_on_conv_err;
  98
  99 private:
 100         std::string Convert(iconv_t cd, const std::string &str) const;
 101
 102 public:
 103         /// Always throws ErrnoError if unable to open iconv.
 104         /// If throw_on_conv_err is true, then string conversion operations
 105         /// that fail will also throw ErrnoError.
 106         explicit IConverter(const char *tocode = "UTF-8", bool throw_on_conv_err = false);
 107         ~IConverter();
 108
 109         std::string FromBB(const std::string &str) const;
 110         std::string ToBB(const std::string &str) const;
 111
 112         // Custom override functions, meant for converting between
 113         // non-BLACKBERRY_CHARSET charsets and the tocode set by the
 114         // IConverter constructor
 115         std::string Convert(const IConvHandle &custom, const std::string &str) const;
 116 };
 117
 118 } // namespace Barry
 119
 120 #endif
 121