X-Git-Url: http://git.tdb.fi/?p=libs%2Fcore.git;a=blobdiff_plain;f=source%2Fstringcodec%2Fcodec.h;h=d0871ff119ab563ea2ff000ece006c55577ddf48;hp=a307e2ec8acc3a784d1f57ce9d7ca4516dfff4fc;hb=017feade2799ddbecad62b9a7911bf4d3e229dad;hpb=b011b17393069d86790b2291a759280e15c75a0f

diff --git a/source/stringcodec/codec.h b/source/stringcodec/codec.h
index a307e2e..d0871ff 100644
--- a/source/stringcodec/codec.h
+++ b/source/stringcodec/codec.h
@@ -2,31 +2,20 @@
 #define MSP_STRINGCODEC_CODEC_H_
 
 #include <string>
-#include <msp/core/except.h>
+#include "except.h"
+#include "ustring.h"
 
 namespace Msp {
 namespace StringCodec {
 
-typedef int UnicodeChar;
-
-typedef std::basic_string<UnicodeChar> ustring;
-
 enum ErrorMode
 {
+	DEFAULT,
 	THROW_ON_ERROR,
 	IGNORE_ERRORS,
 	TRANSLITERATE
 };
 
-/**
-An exception thrown for all kinds of problems encountered while encoding or
-decoding strings.
-*/
-class CodecError: public Exception
-{
-public:
-	CodecError(const std::string &w_): Exception(w_) { }
-};
 
 /**
 Base class for string codecs.  Use one of the derived classes or the function
@@ -52,13 +41,13 @@ public:
 	protected:
 		ErrorMode err_mode;
 
-		Encoder(ErrorMode em): err_mode(em) { }
+		Encoder(ErrorMode em): err_mode(em==DEFAULT ? THROW_ON_ERROR : em) { }
 	public:
 		virtual ~Encoder() { }
 
 		/** Encodes a single unicode character.  If the character can't be
 		represented in this encoding, error() should be called. */
-		virtual void encode_char(UnicodeChar ch, std::string &buf) = 0;
+		virtual void encode_char(unichar ch, std::string &buf) = 0;
 
 		/** Encodes a unicode string.  This is equivalent to calling encode_char
 		for each character in the string with the same buffer. */
@@ -76,14 +65,21 @@ public:
 	protected:
 		/** Handles an error depending on the error mode.
 
-		THROW_ON_ERROR: throws CodecError(msg)
+		THROW_ON_ERROR: throws err
 		IGNORE_ERRORS: does nothing
 		TRANSLITERATE: calls transliterate(ch, buf) */
-		void error(UnicodeChar ch, std::string &buf, const std::string &msg);
+		template<typename E>
+		void error(unichar ch, std::string &buf, const E &err)
+		{
+			if(err_mode==TRANSLITERATE)
+				transliterate(ch, buf);
+			else if(err_mode!=IGNORE_ERRORS)
+				throw err;
+		}
 
 		/** Attempts to produce an alternative encoding for a unicode character.
 		Typically this includes dropping accent marks or romanizing letters. */
-		virtual void transliterate(UnicodeChar ch, std::string &buf) = 0;
+		virtual void transliterate(unichar ch, std::string &buf) = 0;
 	};
 
 	/**
@@ -96,7 +92,7 @@ public:
 	protected:
 		ErrorMode err_mode;
 
-		Decoder(ErrorMode em): err_mode(em) { }
+		Decoder(ErrorMode em): err_mode(em==DEFAULT ? THROW_ON_ERROR : em) { }
 	public:
 		virtual ~Decoder() { }
 
@@ -105,7 +101,7 @@ public:
 		state change sequence was decoded but no character followed it.  If
 		invalid input is encountered, the error() function should be called and
 		the iterator advanced only if it doesn't throw. */
-		virtual UnicodeChar decode_char(const std::string &str, std::string::const_iterator &i) = 0;
+		virtual unichar decode_char(const std::string &str, std::string::const_iterator &i) = 0;
 
 		/** Decodes a string. */
 		virtual void decode(const std::string &str, ustring &buf);
@@ -119,10 +115,19 @@ public:
 		/** Handles an error depending on the error mode.  The return value is
 		suitable for returning from decode_char.
 		
-		THROW_ON_ERROR: throws CodecError(msg)
+		THROW_ON_ERROR: throws err
 		IGNORE_ERRORS: returns -1
-		TRANSLITERATE: return 0xFFFE */
-		UnicodeChar error(const std::string &msg);
+		TRANSLITERATE: return 0xFFFD */
+		template<typename E>
+		unichar error(const E &err)
+		{
+			if(err_mode==TRANSLITERATE)
+				return 0xFFFD;
+			else if(err_mode==IGNORE_ERRORS)
+				return -1;
+			else
+				throw err;
+		}
 	};
 
 protected:
@@ -134,10 +139,10 @@ public:
 	virtual const char *get_name() const = 0;
 
 	/** Creates an encoder for this codec. */
-	virtual Encoder *create_encoder(ErrorMode err_mode = THROW_ON_ERROR) const = 0;
+	virtual Encoder *create_encoder(ErrorMode err_mode = DEFAULT) const = 0;
 
 	/** Creates a decoder for this codec. */
-	virtual Decoder *create_decoder(ErrorMode err_mode = THROW_ON_ERROR) const = 0;
+	virtual Decoder *create_decoder(ErrorMode err_mode = DEFAULT) const = 0;
 
 	/** Determines whether the given string can be successfully decoded with
 	this codec.  Note that this function returning true does not guarantee that
@@ -149,8 +154,30 @@ public:
 typedef Codec::Encoder Encoder;
 typedef Codec::Decoder Decoder;
 
+
+/**
+A helper class to provide some common functionality.
+*/
+template<typename C>
+class StandardCodec: public Codec
+{
+private:
+	ErrorMode err_mode;
+
+protected:
+	StandardCodec(ErrorMode em): err_mode(em==DEFAULT ? THROW_ON_ERROR : em) { }
+
+public:
+	virtual Encoder *create_encoder(ErrorMode em = DEFAULT) const
+	{ return new typename C::Encoder(em==DEFAULT ? err_mode : em); }
+
+	virtual Decoder *create_decoder(ErrorMode em = DEFAULT) const
+	{ return new typename C::Decoder(em==DEFAULT ? err_mode : em); }
+};
+
+
 /** Convenience function that decodes a string. */
-template<class C>
+template<typename C>
 ustring decode(const std::string &s)
 {
 	typename C::Decoder dec;
@@ -158,7 +185,7 @@ ustring decode(const std::string &s)
 }
 
 /** Convenience function that encodes a string. */
-template<class C>
+template<typename C>
 std::string encode(const ustring &s)
 {
 	typename C::Encoder enc;
@@ -166,7 +193,7 @@ std::string encode(const ustring &s)
 }
 
 /** Convenience function that transcodes a string from one codec to another. */
-template<class F, class T>
+template<typename F, typename T>
 std::string transcode(const std::string &s)
 {
 	return encode<T>(decode<F>(s));