From b171eeebebb8020091e28de3e874f68efb6ef36f Mon Sep 17 00:00:00 2001
From: 5eraph <5eraph@protonmail.com>
Date: Mon, 24 Oct 2022 18:00:21 +0200
Subject: [PATCH] Allow custom reference in #topup transactions

---
 func/common.fc         | 1 +
 func/nft-collection.fc | 4 ++--
 func/nft-item.fc       | 2 +-
 3 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/func/common.fc b/func/common.fc
index 6dc01da..95ade3e 100644
--- a/func/common.fc
+++ b/func/common.fc
@@ -52,6 +52,7 @@ const int err::invalid_auction_config = 223;
 
 int mod(int x, int y) asm "MOD";
 int equal_slices(slice a, slice b) asm "SDEQ";
+int is_prefix_of(slice a, slice b) asm "SDPFX";
 int builder_null?(builder b) asm "ISNULL";
 builder store_builder(builder to, builder from) asm "STBR";
 
diff --git a/func/nft-collection.fc b/func/nft-collection.fc
index 20057bc..66fa661 100644
--- a/func/nft-collection.fc
+++ b/func/nft-collection.fc
@@ -39,8 +39,8 @@ _ unwrap_signed_cmd(slice signed_cmd, int public_key, int subwallet_id, int msg_
 
     if (op == 0) { ;; regular money transfer
         ;; NB: it is not possible to recover any money transferred to this account
-        ;; so we return back all transfers except ones with comment #topup in it
-        throw_unless(err::wrong_topup_comment, equal_slices(in_msg_body, "#topup") & (in_msg_body.slice_refs() == 0));
+        ;; so we return back all transfers except ones with comment starting #topup in it
+        throw_unless(err::wrong_topup_comment, is_prefix_of("#topup", in_msg_body) & (in_msg_body.slice_refs() == 0));
 
         return ();
     }
diff --git a/func/nft-item.fc b/func/nft-item.fc
index ce3586b..98cbbb3 100644
--- a/func/nft-item.fc
+++ b/func/nft-item.fc
@@ -216,7 +216,7 @@ cell change_dns_record(cell dns, slice in_msg_body) {
     }
 
     if (op == 0) {
-        int is_topup = equal_slices(in_msg_body, "#topup") & (in_msg_body.slice_refs() == 0);
+        int is_topup = is_prefix_of("#topup", in_msg_body) & (in_msg_body.slice_refs() == 0);
         throw_unless(err::forbidden_topup, is_topup | equal_slices(sender_address, owner_address)); ;; only owner can fill-up balance, prevent coins lost right after the auction
         ;; if owner send bid right after auction he can restore it by transfer response message
         return ();