Added filtered output stream to transform LFs to CRLFs.

src/utility/filteredStream.cpp

@@ -286,6 +286,77 @@ void CRLFToLFFilteredOutputStream::flush()
 }
 
 
+// LFToCRLFFilteredOutputStream
+
+LFToCRLFFilteredOutputStream::LFToCRLFFilteredOutputStream(outputStream& os)
+	: m_stream(os), m_previousChar('\0')
+{
+}
+
+
+outputStream& LFToCRLFFilteredOutputStream::getNextOutputStream()
+{
+	return (m_stream);
+}
+
+
+void LFToCRLFFilteredOutputStream::write
+	(const value_type* const data, const size_type count)
+{
+	if (count == 0)
+		return;
+
+	std::string buffer;
+	buffer.reserve(count);
+
+	const value_type* pos = data;
+	const value_type* end = data + count;
+
+	value_type previousChar = m_previousChar;
+
+	while (pos < end)
+	{
+		switch (*pos)
+		{
+		case '\r':
+
+			buffer.append(1, '\r');
+			buffer.append(1, '\n');
+
+			break;
+
+		case '\n':
+
+			if (previousChar != '\r')
+			{
+				buffer.append(1, '\r');
+				buffer.append(1, '\n');
+			}
+
+			break;
+
+		default:
+
+			buffer.append(1, *pos);
+			break;
+		}
+
+		previousChar = *pos;
+		++pos;
+	}
+
+	m_stream.write(&buffer[0], buffer.length());
+
+	m_previousChar = previousChar;
+}
+
+
+void LFToCRLFFilteredOutputStream::flush()
+{
+	m_stream.flush();
+}
+
+
 // stopSequenceFilteredInputStream <1>
 
 template <>

tests/testUtils.hpp

@@ -53,6 +53,8 @@
 
 #define VASSERT_EQ(msg, expected, actual) \
 	CPPUNIT_ASSERT_EQUAL_MESSAGE(std::string(msg), expected, actual)
+#define VASSERT_NEQ(msg, expected, actual) \
+	CPPUNIT_ASSERT_MESSAGE(std::string(msg), (expected) != (actual))
 
 #define VASSERT_THROW(msg, expression, exceptionType) \
 	CPPUNIT_ASSERT_THROW(expression, exceptionType)

tests/utility/filteredStreamTest.cpp

@@ -35,6 +35,8 @@ VMIME_TEST_SUITE_BEGIN(filteredStreamTest)
 		VMIME_TEST(testStopSequenceFilteredInputStream1)
 		VMIME_TEST(testStopSequenceFilteredInputStreamN_2)
 		VMIME_TEST(testStopSequenceFilteredInputStreamN_3)
+		VMIME_TEST(testLFToCRLFFilteredOutputStream_Global)
+		VMIME_TEST(testLFToCRLFFilteredOutputStream_Edge)
 	VMIME_TEST_LIST_END
 
 
@@ -276,5 +278,43 @@ VMIME_TEST_SUITE_BEGIN(filteredStreamTest)
 		testStopSequenceFISHelper <3>("24", "xyz", "", "x", "y", "z");
 	}
 
+
+	// LFToCRLFFilteredOutputStream
+
+	void testLFToCRLFFilteredOutputStream_Global()
+	{
+		typedef vmime::utility::LFToCRLFFilteredOutputStream FILTER;
+
+		testFilteredOutputStreamHelper<FILTER>("1",  "ABC\r\nDEF",       "ABC\nDEF");
+		testFilteredOutputStreamHelper<FILTER>("2",  "ABC\r\nDEF",       "ABC\rDEF");
+		testFilteredOutputStreamHelper<FILTER>("3",  "\r\n\r\nAB\r\n\r\nA\r\nB\r\n", "\n\nAB\n\nA\nB\n");
+		testFilteredOutputStreamHelper<FILTER>("4",  "ABCDE\r\nF",       "ABCDE\nF");
+		testFilteredOutputStreamHelper<FILTER>("5",  "ABCDE\r\nF",       "ABCDE\r\nF");
+		testFilteredOutputStreamHelper<FILTER>("6",  "\r\n\r\n\r\n",     "\n\n\n");
+		testFilteredOutputStreamHelper<FILTER>("7",  "\r\n\r\n\r\n",     "\r\r\n\n");
+		testFilteredOutputStreamHelper<FILTER>("8",  "\r\n\r\n\r\n\r\n", "\r\r\r\r");
+		testFilteredOutputStreamHelper<FILTER>("9",  "\r\n\r\n\r\n\r\n", "\n\n\n\n");
+		testFilteredOutputStreamHelper<FILTER>("10", "\r\n\r\n\r\n",     "\r\n\n\n");
+		testFilteredOutputStreamHelper<FILTER>("11", "\r\n\r\n\r\n\r\n", "\n\n\n\r\n");
+	}
+
+	void testLFToCRLFFilteredOutputStream_Edge()
+	{
+		typedef vmime::utility::LFToCRLFFilteredOutputStream FILTER;
+
+		testFilteredOutputStreamHelper<FILTER>("1",  "\r\n\r\n",         "\r", "\r");
+		testFilteredOutputStreamHelper<FILTER>("2",  "\r\n\r\n",         "\r", "\n\r");
+		testFilteredOutputStreamHelper<FILTER>("3",  "ABC\r\n\r\n",      "ABC\r", "\n\r");
+		testFilteredOutputStreamHelper<FILTER>("4",  "ABC\r\n\r\n\r\n",  "ABC\r", "\n\r", "\n\n");
+		testFilteredOutputStreamHelper<FILTER>("5",  "\r\n\r\n",         "\n", "\n");
+		testFilteredOutputStreamHelper<FILTER>("6",  "\r\n\r\n",         "\r\n\r\n");
+		testFilteredOutputStreamHelper<FILTER>("7",  "\r\n\r\n",         "\r\n\r", "\n");
+
+		testFilteredOutputStreamHelper<FILTER>("8",  "A\r\nB\r\nC\r\nD",         "A\rB", "\nC\r\nD");
+		testFilteredOutputStreamHelper<FILTER>("9",  "\r\nA\r\nB\r\nC\r\nD",     "\rA\r", "B\nC\r\nD");
+		testFilteredOutputStreamHelper<FILTER>("10", "\r\nA\r\nB\r\nC\r\nD",     "\nA\r", "B\nC\r\nD");
+		testFilteredOutputStreamHelper<FILTER>("11", "\r\nA\r\nB\r\nC\r\nD\r\n", "\nA\rB", "\nC\r\nD\r");
+	}
+
 VMIME_TEST_SUITE_END
 

vmime/utility/filteredStream.hpp

@@ -155,6 +155,32 @@ private:
 };
 
 
+/** A filtered output stream which replaces CR or LF characters
+  * with CRLF sequences.
+  */
+
+class LFToCRLFFilteredOutputStream : public filteredOutputStream
+{
+public:
+
+	/** Construct a new filter for the specified output stream.
+	  *
+	  * @param os stream into which write filtered data
+	  */
+	LFToCRLFFilteredOutputStream(outputStream& os);
+
+	outputStream& getNextOutputStream();
+
+	void write(const value_type* const data, const size_type count);
+	void flush();
+
+private:
+
+	outputStream& m_stream;
+	value_type m_previousChar;
+};
+
+
 /** A filtered input stream which stops when a specified sequence
   * is found (eof() method will return 'true').
   */