use separate column for device-msg-labels

src/chat.rs

@@ -1940,9 +1940,17 @@ pub fn add_device_msg_once(
 ) -> Result<MsgId, Error> {
     let (chat_id, _blocked) =
         create_or_lookup_by_contact_id(context, DC_CONTACT_ID_DEVICE, Blocked::Not)?;
-    let rfc724_mid = format!("{}@device", label);
+    let rfc724_mid = dc_create_outgoing_rfc724_mid(None, "@device");
 
-    if let Ok((_, _, msg_id)) = message::rfc724_mid_exists(context, &rfc724_mid) {
+    // chat_id has an sql-index so it makes sense to add this although redundant
+    if let Ok(msg_id) = context.sql.query_row(
+        "SELECT id FROM msgs WHERE chat_id=? AND label=?",
+        params![chat_id, label],
+        |row| {
+            let msg_id: MsgId = row.get(0)?;
+            Ok(msg_id)
+        },
+    ) {
         info!(
             context,
             "device-message {} already exist as {}", label, msg_id
@@ -1954,8 +1962,8 @@ pub fn add_device_msg_once(
     unarchive(context, chat_id)?;
 
     context.sql.execute(
-        "INSERT INTO msgs (chat_id,from_id,to_id, timestamp,type,state, txt,param,rfc724_mid) \
-         VALUES (?,?,?, ?,?,?, ?,?,?);",
+        "INSERT INTO msgs (chat_id,from_id,to_id, timestamp,type,state, txt,param,rfc724_mid,label) \
+         VALUES (?,?,?, ?,?,?, ?,?,?,?);",
         params![
             chat_id,
             DC_CONTACT_ID_DEVICE,
@@ -1966,6 +1974,7 @@ pub fn add_device_msg_once(
             msg.text.as_ref().map_or("", String::as_str),
             msg.param.to_string(),
             rfc724_mid,
+            label,
         ],
     )?;
 

src/imex.rs

@@ -160,6 +160,7 @@ fn do_initiate_key_transfer(context: &Context) -> Result<String> {
     // it would be too much noise to have two things popping up at the same time.
     // maybe_add_bcc_self_device_msg() is called on the other device
     // once the transfer is completed.
+    maybe_add_bcc_self_device_msg(context)?;
     Ok(setup_code)
 }
 

src/sql.rs

@@ -806,12 +806,19 @@ fn open(
             )?;
             sql.set_raw_config_int(context, "dbversion", 55)?;
         }
-        if dbversion < 56 {
-            info!(context, "[migration] v56");
+        if dbversion < 57 {
+            info!(context, "[migration] v57");
+            // label is a unique name and is currently used for device-messages only.
+            // in contrast to rfc724_mid and other fields, the label is generated on the device
+            // and allows reliable identifications this way.
+            sql.execute(
+                "ALTER TABLE msgs ADD COLUMN label TEXT DEFAULT '';",
+                params![],
+            )?;
             if exists_before_update && sql.get_raw_config_int(context, "bcc_self").is_none() {
                 sql.set_raw_config_int(context, "bcc_self", 1)?;
             }
-            sql.set_raw_config_int(context, "dbversion", 56)?;
+            sql.set_raw_config_int(context, "dbversion", 57)?;
         }
 
         // (2) updates that require high-level objects