doveadm backup: Another attempt at fixing assert-crashes when deleting mailboxes.

Only two-way syncs really care about the mailbox deletion logs which set
existence=DELETED. So actually the log reading could be skipped entirely for
doveadm backup to speed things up.

In any case the code currently relies that after
sync_tree_sort_and_delete_mailboxes() the tree no longer has nodes with
existence=DELETED and mailbox_guid!=0, because that assert-crashes in
sync_create_mailboxes(). The assert() could probably simply be changed into
an if(), but might as well keep the code as it was originally intended and
not have the sync/backup behave more differently than needed.

diff --git a/src/doveadm/dsync/dsync-mailbox-tree-sync.c b/src/doveadm/dsync/dsync-mailbox-tree-sync.c
index 8432c99fbdf8f855cf386cee0b614a1964134935..65fee12a9e5a197dae1399f441ac3d3b9ab62510 100644 (file)
--- a/src/doveadm/dsync/dsync-mailbox-tree-sync.c
+++ b/src/doveadm/dsync/dsync-mailbox-tree-sync.c
@@ -199,16 +199,10 @@ sync_delete_mailbox(struct dsync_mailbox_tree_sync_ctx *ctx,
        sync_delete_mailbox_node(ctx, tree, node, reason);
 }
 
-enum del_sync_type {
-       DEL_SYNC_TYPE_TWOWAY,
-       DEL_SYNC_TYPE_RESTORE,
-       DEL_SYNC_TYPE_IGNORE
-};
-
 static void
 sync_tree_sort_and_delete_mailboxes(struct dsync_mailbox_tree_sync_ctx *ctx,
                                    struct dsync_mailbox_tree *tree,
-                                   enum del_sync_type del_sync_type)
+                                   bool twoway_sync)
 {
        struct dsync_mailbox_tree_bfs_iter *iter;
        struct dsync_mailbox_node *node, *parent = NULL;
@@ -225,20 +219,19 @@ sync_tree_sort_and_delete_mailboxes(struct dsync_mailbox_tree_sync_ctx *ctx,
                }
                if (node->existence == DSYNC_MAILBOX_NODE_DELETED &&
                    !dsync_mailbox_node_is_dir(node)) {
-                       switch (del_sync_type) {
-                       case DEL_SYNC_TYPE_TWOWAY:
+                       if (twoway_sync) {
                                /* this mailbox was deleted. delete it from the
                                   other side as well */
                                sync_delete_mailbox(ctx, tree, node,
                                                    "Mailbox has been deleted");
-                               break;
-                       case DEL_SYNC_TYPE_RESTORE:
-                               /* we want to restore the mailbox back.
-                                  just treat it as if it didn't exist */
+                       } else {
+                               /* treat the node as if it didn't exist. it'll
+                                  get either recreated or deleted later. in
+                                  any case this function must handle all
+                                  existence=DELETED mailbox nodes by changing
+                                  them into directories (setting GUID=0) or
+                                  we'll assert-crash later */
                                sync_set_node_deleted(tree, node);
-                               break;
-                       case DEL_SYNC_TYPE_IGNORE:
-                               break;
                        }
                }
                array_append(&siblings, &node, 1);
@@ -1213,7 +1206,6 @@ dsync_mailbox_trees_sync_init(struct dsync_mailbox_tree *local_tree,
 {
        struct dsync_mailbox_tree_sync_ctx *ctx;
        pool_t pool;
-       enum del_sync_type del_sync_type;
 
        i_assert(hash_table_is_created(local_tree->guid_hash));
        i_assert(hash_table_is_created(remote_tree->guid_hash));
@@ -1228,34 +1220,10 @@ dsync_mailbox_trees_sync_init(struct dsync_mailbox_tree *local_tree,
        ctx->sync_flags = sync_flags;
        i_array_init(&ctx->changes, 128);
 
-       switch (sync_type) {
-       case DSYNC_MAILBOX_TREES_SYNC_TYPE_TWOWAY:
-               del_sync_type = DEL_SYNC_TYPE_TWOWAY;
-               break;
-       case DSYNC_MAILBOX_TREES_SYNC_TYPE_PRESERVE_REMOTE:
-               del_sync_type = DEL_SYNC_TYPE_IGNORE;
-               break;
-       case DSYNC_MAILBOX_TREES_SYNC_TYPE_PRESERVE_LOCAL:
-               del_sync_type = DEL_SYNC_TYPE_RESTORE;
-               break;
-       default:
-               i_unreached();
-       }
-       sync_tree_sort_and_delete_mailboxes(ctx, remote_tree, del_sync_type);
-       switch (sync_type) {
-       case DSYNC_MAILBOX_TREES_SYNC_TYPE_TWOWAY:
-               del_sync_type = DEL_SYNC_TYPE_TWOWAY;
-               break;
-       case DSYNC_MAILBOX_TREES_SYNC_TYPE_PRESERVE_REMOTE:
-               del_sync_type = DEL_SYNC_TYPE_RESTORE;
-               break;
-       case DSYNC_MAILBOX_TREES_SYNC_TYPE_PRESERVE_LOCAL:
-               del_sync_type = DEL_SYNC_TYPE_IGNORE;
-               break;
-       default:
-               i_unreached();
-       }
-       sync_tree_sort_and_delete_mailboxes(ctx, local_tree, del_sync_type);
+       sync_tree_sort_and_delete_mailboxes(ctx, remote_tree,
+               sync_type == DSYNC_MAILBOX_TREES_SYNC_TYPE_TWOWAY);
+       sync_tree_sort_and_delete_mailboxes(ctx, local_tree,
+               sync_type == DSYNC_MAILBOX_TREES_SYNC_TYPE_TWOWAY);
 
        dsync_mailbox_tree_update_child_timestamps(&local_tree->root, 0);
        dsync_mailbox_tree_update_child_timestamps(&remote_tree->root, 0);