* src/support/docstream.cpp (iconv_codecvt_facet::do_max_length()):

	- consider that not only utf8, but also most cjk encodings, are multibyte encodings
	  (fixes bug 4012)

git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@19076 a592a061-630c-0410-9148-cb99ea01b6c8

diff --git a/src/support/docstream.cpp b/src/support/docstream.cpp
index 8f476376e6f586ca95be86a84bebad417b76bfdc..6c5dd8bed0d6bd3cbbba1e3fbd3d8f4cb9dd1b8f 100644 (file)
--- a/src/support/docstream.cpp
+++ b/src/support/docstream.cpp
@@ -206,13 +206,32 @@ protected:
        }
        virtual int do_max_length() const throw()
        {
+               // FIXME: this information should be transferred to lib/encodings
                // UTF8 uses at most 4 bytes to represent one UCS4 code point
                // (see RFC 3629). RFC 2279 specifies 6 bytes, but that
                // information is outdated, and RFC 2279 has been superseded by
                // RFC 3629.
+               // The CJK encodings use (different) multibyte representation as well.
                // All other encodings encode one UCS4 code point in one byte
                // (and can therefore only encode a subset of UCS4)
-               return encoding_ == "UTF-8" ? 4 : 1;
+               // Note that BIG5 and SJIS do not work with LaTeX (see lib/encodings). 
+               // Furthermore, all encodings that use shifting (like SJIS) do not work with 
+               // iconv_codecvt_facet.
+               if (encoding_ == "UTF-8" ||
+                   encoding_ == "GB" ||
+                   encoding_ == "EUC-TW")
+                       return 4;
+               else if (encoding_ == "EUC-JP")
+                       return 3;
+               else if (encoding_ == "BIG5" ||
+                        encoding_ == "EUC-KR" ||
+                        encoding_ == "EUC-CN" ||
+                        encoding_ == "SJIS" ||
+                        encoding_ == "GBK" ||
+                        encoding_ == "JIS" )
+                       return 2;
+               else
+                       return 1;
        }
 private:
        /// Do the actual conversion. The interface is equivalent to that of