sketch out exceptions that need to be caught or raised

src/pEpTransportMail.cc

@@ -47,8 +47,10 @@ namespace pEp {
             pEpLogClass("called");
             if (allCallbacksRegistered()) {
                 if (ConfigMail *cfg = dynamic_cast<ConfigMail *>(const_cast<Config *>(&config))) {
+                    // or should I just save cfg?
                     login_imap = cfg->login_recv;
                     login_smtp = cfg->login_send;
+                    own_ident = cfg->ident;
                 } else {
                     throw ConfigError("configure(): object has to be of type ConfigMail");
                 }
@@ -80,10 +82,20 @@ namespace pEp {
             // and then populate rx_queue via conn_imap.select()
             try {
                 conn_imap = new mailio::imaps(login_imap.server, login_imap.port);
-            } catch (mailio::imap_error e) {
-                pEpLogClass(e.what());
+            } catch (mailio::dialog_error e) {
+                pEpLogClass("dialog error: " + std::string(e.what()));
+                // TODO:
                 // set tsc and PEP_STATUS
+                // Possible values:
+                // PEP_tsc_cannot_reach_imap_server = 0x01802001
+                // PEP_tsc_network_timeout = 0x0080000a,
+                // PEP_tsc_no_recv_config = 0x00800007,
+                // PEP_tsc_recv_config_incomplete_or_wrong = 0x00800009,
+                // return. If IMAP connection failed, this transport can and must not be used.
             }
+            // Does auth get its own error handling or do I put it into the previous try block?
+            // may fail with imap_error,
+            // PEP_tsc_recv_config_incomplete_or_wrong = 0x00800009,
             conn_imap->authenticate(login_imap.username, login_imap.passphrase, login_imap.auth_method);
             if (!protocol_thread.joinable()) {
                 protocol_thread_stop.store(false);
@@ -127,7 +139,14 @@ namespace pEp {
 
             mailio_message mmsg(msg);
             ::PEP_transport_status_code pep_tsc = PEP_tsc_message_on_the_way;
+            // creating conn may fail. -> seperate variable definition and connection, meaning we need conn to be a pointer of some sort and call new inside a try block.
+            // Possible tsc values:
+            // PEP_tsc_cannot_reach_smtp_server
+            // PEP_tsc_network_timeout
+            // PEP_tsc_no_send_config
+            // PEP_tsc_send_config_incomplete_or_wrong
             mailio::smtps conn(login_smtp.server, login_smtp.port);
+            // That would make this check obsolete (and it doesn't work as intended anyways)
             if (conn.source_hostname().empty()) {
                 pEpLogClass("SMTP no connection");
             } else {
@@ -140,6 +159,8 @@ namespace pEp {
                 // Other possible values:
                 // PEP_tsc_network_timeout = 0x0080000a,
                 // PEP_tsc_unknown_smtp_error = 0x01801fff,
+                // PEP_tsc_no_send_config
+                // PEP_tsc_send_config_incomplete_or_wrong
             }
             try {
                 std::string answer = conn.submit(mmsg); // TODO: log the result
@@ -148,6 +169,7 @@ namespace pEp {
                 pEpLogClass(e.what());
                 pep_tsc = PEP_tsc_could_not_deliver_giving_up;
                 // Possible values depending on the error code:
+                // If we get a good enough error code, that is. Another point to question the use of mailio.
                 // PEP_tsc_some_recipients_unreachable = 0x00800002,
                 // PEP_tsc_no_recipients_reachable = 0x00800003,
                 // PEP_tsc_network_timeout = 0x0080000a,
@@ -158,7 +180,9 @@ namespace pEp {
             // if nothing failed, pep_tsc is still PEP_tsc_message_on_the_way
             cb_sendto_result(get_id(), msg->id, pep_tsc);
             try {
-                conn_imap->append("sent", mmsg);
+                conn_imap->append("Sent", mmsg);
+                // This usually fails in the test, I don't know why.
+                // And I'm not even sure if it's a) needed or b) even asked for?
             } catch (mailio::imap_error e) {
                 pEpLogClass(e.what());
             }
@@ -182,6 +206,10 @@ namespace pEp {
                     mailio::codec::line_len_policy_t::MANDATORY);
 
                 // get that mail from mailio
+                // this might fail.
+                // Possible tsc values:
+                // PEP_tsc_cannot_reach_imap_server = 0x01802001,
+                // PEP_tsc_unknown_imap_error = 0x01802fff,
                 conn_imap->fetch("inbox", message_id, mmsg, false);
 
                 // Convert the mailio message struct into a pEp message struct using our conversion operator.
@@ -205,7 +233,7 @@ namespace pEp {
         std::string pEpTransportMail::own_address()
         {
             throwInvalidState();
-            return "alice@pep.foundation";
+            return std::string(own_ident->address);
         }
 
         bool pEpTransportMail::shortmsg_supported()