X-Git-Url: http://git.tdb.fi/?p=libs%2Fcore.git;a=blobdiff_plain;f=source%2Fstringcodec%2Futf8.cpp;fp=source%2Fstringcodec%2Futf8.cpp;h=c7e1705f814e2d099d3b0180730c57e3aa210d85;hp=0000000000000000000000000000000000000000;hb=b42ed73a1b241c0e93ee03c43c4584b41c549bac;hpb=5b1368cb791cab043f0435628cacbaff36e39b7b

diff --git a/source/stringcodec/utf8.cpp b/source/stringcodec/utf8.cpp
new file mode 100644
index 0000000..c7e1705
--- /dev/null
+++ b/source/stringcodec/utf8.cpp
@@ -0,0 +1,92 @@
+/* $Id$
+
+This file is part of libmspstrings
+Copyright © 2006-2007 Mikko Rasa
+Distributed under the LGPL
+*/
+
+#include "utf8.h"
+
+using namespace std;
+
+namespace Msp {
+namespace Codecs {
+
+void Utf8::Encoder::encode_char(UnicodeChar ch, string &buf)
+{
+	if(ch<0 || ch>0x10FFFF)
+		return error(ch, buf, "Can't express character in UTF-8");
+
+	unsigned bytes = 1;
+	if(ch>0xFFFF)
+		bytes = 4;
+	else if(ch>0x7FF)
+		bytes = 3;
+	else if(ch>0x7F)
+		bytes = 2;
+
+	if(bytes==1)
+		buf += ch;
+	else
+	{
+		char utf[4];
+
+		utf[0] = 0xFF<<(8-bytes) | ch>>(bytes*6-6);
+		for(unsigned j=bytes-1; j>0; --j)
+		{
+			utf[j] = 0x80 | (ch&0x3F);
+			ch >>= 6;
+		}
+
+		buf.append(utf, bytes);
+	}
+}
+
+void Utf8::Encoder::transliterate(UnicodeChar, string &buf)
+{
+	buf.append("\357\277\275", 3);  // � U+FFFE Replacement Character
+}
+
+
+UnicodeChar Utf8::Decoder::decode_char(const string &str, string::const_iterator &i)
+{
+	if(i==str.end())
+		return error("No input");
+
+	if((*i&0xC0)==0x80)
+	{
+		UnicodeChar result = error("UTF-8 tail byte found when expecting head");
+		++i;
+		return result;
+	}
+	else if(*i&0x80)
+	{
+		unsigned bytes = 2;
+		unsigned mask = 0x20;
+		for(; *i&mask; mask>>=1)
+			++bytes;
+
+		string::const_iterator j = i;
+
+		UnicodeChar result = (*j++)&(mask-1);
+
+		unsigned k;
+		for(k=1; (k<bytes && j!=str.end() && (*j&0xC0)==0x80); ++k)
+			result = (result<<6) | ((*j++)&0x3F);
+
+		if(k<bytes)
+			result = error("Incomplete UTF-8 character");
+		else if(!(result>>(bytes*5-4)) || !(result>>7))
+			result = error("Denormalized UTF-8 multibyte sequence");
+		else if(result>0x10FFFF || (result>=0xD800 && result<=0xDFFF))
+			result = error("Invalid Unicode code point");
+
+		i = j;
+		return result;
+	}
+	else
+		return *i++;
+}
+
+} // namespace Codecs
+} // namespace Msp