lib: Implement versioning in the database and provide upgrade function.

[notmuch] / lib / message.cc

diff --git a/lib/message.cc b/lib/message.cc
index ea9c8bd96afb1b34ccb8ebb329c5f93ebcaa344b..baeaa46972867d10a1cc5cde801fac03c0817df1 100644 (file)
--- a/lib/message.cc
+++ b/lib/message.cc
@@ -416,6 +416,24 @@ _notmuch_message_add_filename (notmuch_message_t *message,
     return NOTMUCH_STATUS_SUCCESS;
 }
 
+/* Move the filename from the data field (as it was in database format
+ * version 0) to a file-direntry term instead (as in database format
+ * version 1).
+ */
+void
+_notmuch_message_upgrade_filename_storage (notmuch_message_t *message)
+{
+    char *filename;
+
+    filename = talloc_strdup (message, message->doc.get_data ().c_str ());
+    if (filename && *filename != '\0') {
+       _notmuch_message_add_filename (message, filename);
+       message->doc.set_data ("");
+       _notmuch_message_sync (message);
+    }
+    talloc_free (filename);
+}
+
 const char *
 notmuch_message_get_filename (notmuch_message_t *message)
 {
@@ -441,7 +459,10 @@ notmuch_message_get_filename (notmuch_message_t *message)
     {
        /* A message document created by an old version of notmuch
         * (prior to rename support) will have the filename in the
-        * data of the document rather than as a file-direntry term. */
+        * data of the document rather than as a file-direntry term.
+        *
+        * It would be nice to do the upgrade of the document directly
+        * here, but the database is likely open in read-only mode. */
        const char *data;
 
        data = message->doc.get_data ().c_str ();