lib: publish API for notmuch_database_reopen

Include the (currently unused) mode argument which will specify which
mode to re-open the database in. Functionality and docs to be
finalized in a followup commit.

lib/database.cc

@@ -518,7 +518,8 @@ notmuch_database_close (notmuch_database_t *notmuch)
 }
 
 notmuch_status_t
-_notmuch_database_reopen (notmuch_database_t *notmuch)
+notmuch_database_reopen (notmuch_database_t *notmuch,
+			 unused(notmuch_database_mode_t mode))
 {
     if (_notmuch_database_mode (notmuch) != NOTMUCH_DATABASE_MODE_READ_ONLY)
 	return NOTMUCH_STATUS_UNSUPPORTED_OPERATION;

lib/message.cc

@@ -459,7 +459,8 @@ _notmuch_message_ensure_metadata (notmuch_message_t *message, void *field)
 	    /* all the way without an exception */
 	    break;
 	} catch (const Xapian::DatabaseModifiedError &error) {
-	    notmuch_status_t status = _notmuch_database_reopen (message->notmuch);
+	    notmuch_status_t status = notmuch_database_reopen (message->notmuch,
+							       NOTMUCH_DATABASE_MODE_READ_ONLY);
 	    if (status != NOTMUCH_STATUS_SUCCESS)
 		INTERNAL_ERROR ("unhandled error from notmuch_database_reopen: %s\n",
 				notmuch_status_to_string (status));

lib/notmuch-private.h

@@ -204,9 +204,6 @@ _notmuch_message_id_compressed (void *ctx, const char *message_id);
 notmuch_status_t
 _notmuch_database_ensure_writable (notmuch_database_t *notmuch);
 
-notmuch_status_t
-_notmuch_database_reopen (notmuch_database_t *notmuch);
-
 void
 _notmuch_database_log (notmuch_database_t *notmuch,
 		       const char *format, ...);

lib/notmuch.h

@@ -879,6 +879,13 @@ notmuch_database_find_message_by_filename (notmuch_database_t *notmuch,
 notmuch_tags_t *
 notmuch_database_get_all_tags (notmuch_database_t *db);
 
+/**
+ * Reopen an open notmuch database.
+ *
+ */
+notmuch_status_t
+notmuch_database_reopen (notmuch_database_t *db, notmuch_database_mode_t mode);
+
 /**
  * Create a new query for 'database'.
  *