Configurable email add domain (#287)

* Allow appending of local hostname to be configured via parsing context

Signed-off-by: Ben Magistro <koncept1@gmail.com>
Co-authored-by: Vincent Richard <vincent@vincent-richard.net>

src/vmime/emailAddress.cpp

@@ -176,7 +176,7 @@ emailAddress::emailAddress(const word& localName, const word& domainName)
 
 
 void emailAddress::parseImpl(
-	const parsingContext& /* ctx */,
+	const parsingContext& ctx,
 	const string& buffer,
 	const size_t position,
 	const size_t end,
@@ -541,7 +541,7 @@ void emailAddress::parseImpl(
 	} else {
 
 		// If the domain part is missing, use local host name
-		if (domainPart.str().empty() && !atFound) {
+		if (ctx.getUseMyHostname() && domainPart.str().empty() && !atFound) {
 			domainPart << platform::getHandler()->getHostName();
 		}
 
@@ -595,16 +595,28 @@ void emailAddress::generateImpl(
 		domainPart = domainNameToIDNA(m_domainName.getConvertedText(vmime::charsets::UTF_8));
 	}
 
-	os << localPart
-	   << "@"
-	   << domainPart;
 
-	if (newLinePos) {
+	if (!domainPart.empty()) {
+		os << localPart
+			<< "@"
+			<< domainPart;
 
-		*newLinePos = curLinePos
-			+ localPart.length()
-			+ 1 // @
-			+ domainPart.length();
+		if (newLinePos) {
+			*newLinePos = curLinePos
+				+ localPart.length()
+				+ 1 // @
+				+ domainPart.length();
+		}
+	} else {
+		// this should only be true if m_useMyHostname is false and an address without
+		// an `@` is encountered
+
+		os << localPart;
+
+		if (newLinePos) {
+			*newLinePos = curLinePos
+				+ localPart.length();
+		}
 	}
 }
 
@@ -698,8 +710,12 @@ const text emailAddress::toText() const {
 
 	text txt;
 	txt.appendWord(make_shared <vmime::word>(m_localName));
-	txt.appendWord(make_shared <vmime::word>("@", vmime::charsets::US_ASCII));
-	txt.appendWord(make_shared <vmime::word>(m_domainName));
+	if (!m_domainName.empty()) {
+		// this should only be skipped if m_useMyHostname is false and an address without
+		// an `@` is encountered
+		txt.appendWord(make_shared <vmime::word>("@", vmime::charsets::US_ASCII));
+		txt.appendWord(make_shared <vmime::word>(m_domainName));
+	}
 
 	return txt;
 }

src/vmime/parsingContext.cpp

@@ -61,4 +61,16 @@ void parsingContext::setHeaderParseErrorRecoveryMethod(
 }
 
 
+bool parsingContext::getUseMyHostname() const {
+
+	return m_useMyHostname;
+}
+
+
+void parsingContext::setUseMyHostname(bool useMyHostname) {
+
+	m_useMyHostname = useMyHostname;
+}
+
+
 } // vmime

src/vmime/parsingContext.hpp

@@ -77,9 +77,28 @@ public:
 	  */
 	headerParseRecoveryMethod::headerLineError getHeaderParseErrorRecoveryMethod() const;
 
+	/** Return the current hostname adding behavior when parsing/creating a header field that
+	  * utilizes a domain name.
+	  *
+	  * @retval true The local hostname will be appended if a domain is not present
+	  * @retval false The local hostname will not be appended even if a domain is not present
+	  */
+	bool getUseMyHostname() const;
+
+	/** Enables/disables appending the local hostname in header fields if a domain is not
+	  * not provided and it is required. The default is to append. Changing this can result
+	  * in fields that would violate various RFCs.
+	  */
+	void setUseMyHostname(bool useMyHostname);
+
 protected:
 
 	headerParseRecoveryMethod::headerLineError m_headerParseErrorRecovery;
+
+	/** Flag to indicate if the local hostname should be used/appended
+	  *  for header fields when one is not present.
+	  */
+	bool m_useMyHostname{true};
 };
 
 

src/vmime/path.cpp

@@ -192,6 +192,16 @@ void path::generateImpl(
 			*newLinePos = curLinePos + 2;
 		}
 
+	} else if (!m_localPart.empty() && m_domain.empty()) {
+		// this should only be true if m_useMyHostname is false and an address without
+		// an `@` is encountered
+
+		os << "<" << m_localPart << ">";
+
+		if (newLinePos) {
+			*newLinePos = curLinePos + m_localPart.length() + 2;
+		}
+
 	} else {
 
 		os << "<" << m_localPart << "@" << m_domain << ">";