Allow file owners to revoke active transfers on custody expiry or deletion

src/media_delivery/file_transfer.c

@@ -329,3 +329,14 @@ struct file_transfer_op* file_transfer_pull(struct file_transfer* ft, uint64_t g
 void file_transfer_cancel(struct file_transfer_op* op) {
     if (op) ft_finish(op, -2);
 }
+
+void file_transfer_cancel_object(struct file_transfer* ft, const uint8_t object[16]) {
+    if (!ft) return;
+    for (;;) {
+        struct file_transfer_op* found = NULL;
+        for (struct file_transfer_op* op = ft->ops; op; op = op->next)
+            if (!memcmp(op->object, object, 16)) { found = op; break; }
+        if (!found) break;
+        ft_finish(found, -2);
+    }
+}

src/media_delivery/file_transfer.h

@@ -28,5 +28,7 @@ struct file_transfer_op* file_transfer_pull(struct file_transfer* ft, uint64_t g
                                            const uint8_t object[16], uint64_t size, const char* destination,
                                            file_transfer_done_fn done, void* arg);
 void file_transfer_cancel(struct file_transfer_op* op);
+/* Отозвать все операции объекта (TTL/delete); callbacks приёма вызываются с -2. */
+void file_transfer_cancel_object(struct file_transfer* ft, const uint8_t object[16]);
 
 #endif