src/iconv.h

   1 ///
   2 /// \file       iconv.h
   3 ///             iconv wrapper class, and pluggable interface for records
   4 ///
   5
   6 /*
   7     Copyright (C) 2008-2012, 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 <string>
  28 #include <memory>
  29
  30 namespace Barry {
  31
  32 class IConverter;
  33 class IConvHandlePrivate;
  34
  35 //
  36 // IConvHandle class
  37 //
  38 /// Wrapper class for a two-way iconv_t handle pair.  Automatically
  39 /// handles closing in the destructor.
  40 //
  41 class BXEXPORT IConvHandle
  42 {
  43         friend class IConverter;
  44
  45         std::auto_ptr<IConvHandlePrivate> m_priv;
  46
  47         bool m_throw_on_conv_err;
  48
  49 private:
  50         // no copying
  51         IConvHandle(const IConvHandle &other);
  52         IConvHandle& operator=(const IConvHandle &other);
  53
  54         // private constructor, used only by IConverter
  55         IConvHandle(const char *fromcode, const char *tocode, bool throwable);
  56
  57         // the heart of the conversion
  58         std::string Convert(Data &tmp, const std::string &str) const;
  59
  60 public:
  61         // custom conversions from any to IConverter's 'tocode'
  62         IConvHandle(const char *fromcode, const IConverter &ic,
  63                 bool throw_on_conv_err = false);
  64         // custom conversions from IConverter's 'tocode' to any
  65         IConvHandle(const IConverter &ic, const char *tocode,
  66                 bool throw_on_conv_err = false);
  67         ~IConvHandle();
  68 };
  69
  70 //
  71 // IConverter
  72 //
  73 /// Main charset conversion class, primarily focused on converting
  74 /// between the Blackberry charset and an application-specified one.
  75 /// Additional conversions are possible through custom IConvHandle,
  76 /// but the goal of this class design is to deal with _one_
  77 /// application defined charset, and provide a means to convert
  78 /// to/from that charset to/from any other charset needed by
  79 /// the Blackberry.
  80 ///
  81 /// By default, this class assumes the Blackberry's charset is
  82 /// WINDOWS-1252, but some data, such as SMS message bodies, can have
  83 /// custom charsets as specified by the records.  To convert from
  84 /// such a custom charset, use:
  85 ///
  86 ///      // application sets up IConverter
  87 ///      IConverter ic("UTF-8");
  88 ///
  89 ///      // somewhere in the library, needing to convert
  90 ///      // from UCS2 to whatever the application selected
  91 ///      IConvHandle ucs2("UCS2", ic);
  92 ///      application_string = ic.Convert(ucs2, ucs2_string_data);
  93 ///
  94 ///      // and to convert back...
  95 ///      IConvHandle ucs2_reverse(ic, "UCS2");
  96 ///      ucs2_string = ic.Convert(ucs2_reverse, application_string_data);
  97 ///
  98 class BXEXPORT IConverter
  99 {
 100         friend class IConvHandle;
 101
 102         IConvHandle m_from;
 103         IConvHandle m_to;
 104         std::string m_tocode;
 105
 106         // internal buffer for fast conversions
 107         mutable Data m_buffer;
 108
 109 public:
 110         /// Always throws ErrnoError if unable to open iconv.
 111         /// If throw_on_conv_err is true, then string conversion operations
 112         /// that fail will also throw ErrnoError.
 113         explicit IConverter(const char *tocode = "UTF-8",
 114                 bool throw_on_conv_err = false);
 115         ~IConverter();
 116
 117         std::string FromBB(const std::string &str) const;
 118         std::string ToBB(const std::string &str) const;
 119
 120         // Custom override functions, meant for converting between
 121         // non-BLACKBERRY_CHARSET charsets and the tocode set by the
 122         // IConverter constructor
 123         std::string Convert(const IConvHandle &custom, const std::string &str) const;
 124 };
 125
 126 } // namespace Barry
 127
 128 #endif
 129