When an SMTP server sends an unexpected error code or drops the connection, notice that fact and alert the user instead of silently pretending the message was sent (bug 200647). Thanks to Christian Eyrich <ch.ey@gmx.net> for the patch. r=dmose@mozilla.org; sr=bienvenu@netscape.com

mailnews/compose/src/nsSmtpProtocol.cpp

@@ -353,22 +353,25 @@ const char * nsSmtpProtocol::GetUserDomainName()
 // we suppport the nsIStreamListener interface 
 ////////////////////////////////////////////////////////////////////////////////////////////
 
-// stop binding is a "notification" informing us that the stream associated with aURL is going away. 
-NS_IMETHODIMP nsSmtpProtocol::OnStopRequest(nsIRequest *request, nsISupports *ctxt, nsresult aStatus)
+// stop binding is a "notification" informing us that the stream
+// associated with aURL is going away. 
+NS_IMETHODIMP nsSmtpProtocol::OnStopRequest(nsIRequest *request, nsISupports *ctxt,
+nsresult aStatus)
 {
-  if (aStatus == NS_OK && m_totalAmountRead == 0) {
+  if (aStatus == NS_OK && m_nextState != SMTP_FREE) {
     // if we are getting OnStopRequest() with NS_OK, 
-    // but we haven't read any bytes, that's spells trouble.
-    // it means that the server has dropped us before we could read anything
-    // for example, see bug #158059
-    PR_LOG(SMTPLogModule, PR_LOG_ALWAYS, ("SMTP connection closed, but no data read, so report error"));
-    nsMsgAsyncWriteProtocol::OnStopRequest(nsnull, ctxt, NS_ERROR_CONNECTION_REFUSED);
+    // but we haven't finished clean, that's spells trouble.
+    // it means that the server has dropped us before we could send the whole mail
+    // for example, see bug #200647
+    PR_LOG(SMTPLogModule, PR_LOG_ALWAYS,
+ ("SMTP connection dropped after %ld total bytes read", m_totalAmountRead));
+    nsMsgAsyncWriteProtocol::OnStopRequest(nsnull, ctxt, NS_ERROR_NET_INTERRUPT);
   }
-	else
+  else
     nsMsgAsyncWriteProtocol::OnStopRequest(nsnull, ctxt, aStatus);
 
-	// okay, we've been told that the send is done and the connection is going away. So 
-	// we need to release all of our state
+  // okay, we've been told that the send is done and the connection is going away. So 
+  // we need to release all of our state
   return nsMsgAsyncWriteProtocol::CloseSocket();
 }
 
@@ -650,19 +653,34 @@ PRInt32 nsSmtpProtocol::SendEhloResponse(nsIInputStream * inputStream, PRUint32
 
     if (m_responseCode != 250)
     {
-      /* EHLO must not be implemented by the server so fall back to the HELO case */
-
-        if (m_prefTrySSL == PREF_SSL_ALWAYS)
+        /* EHLO must not be implemented by the server so fall back to the HELO case */
+        if (m_responseCode >= 500 && m_responseCode < 550)
         {
-            m_nextState = SMTP_ERROR_DONE;
-            m_urlErrorState = NS_ERROR_COULD_NOT_LOGIN_TO_SMTP_SERVER;
+            if (m_prefTrySSL == PREF_SSL_ALWAYS)
+            {
+                m_nextState = SMTP_ERROR_DONE;
+                m_urlErrorState = NS_ERROR_COULD_NOT_LOGIN_TO_SMTP_SERVER;
+                return(NS_ERROR_COULD_NOT_LOGIN_TO_SMTP_SERVER);
+            }
+
+            buffer = "HELO ";
+            buffer += GetUserDomainName();
+            buffer += CRLF;
+            status = SendData(url, buffer.get());
+        }
+        // e.g. getting 421 "Server says unauthorized, bye"
+        else
+        {
+#ifdef DEBUG
+            nsresult rv = 
+#endif
+            nsExplainErrorDetails(m_runningURL,
+                          NS_ERROR_SMTP_SERVER_ERROR, m_responseText.get());
+            NS_ASSERTION(NS_SUCCEEDED(rv), "failed to explain SMTP error");
+
+            m_urlErrorState = NS_ERROR_BUT_DONT_SHOW_ALERT;
             return(NS_ERROR_COULD_NOT_LOGIN_TO_SMTP_SERVER);
         }
-        buffer = "HELO ";
-        buffer += GetUserDomainName();
-        buffer += CRLF;
-
-        status = SendData(url, buffer.get());
 
         m_nextState = SMTP_RESPONSE;
         m_nextStateAfterResponse = SMTP_SEND_HELO_RESPONSE;