From e0b64c6b2f6f75ed683942ed5b5c3c66fad66dc4 Mon Sep 17 00:00:00 2001
From: Michal Kuratczyk <michal.kuratczyk@broadcom.com>
Date: Tue, 14 Jan 2025 16:12:05 +0100
Subject: [PATCH] Allow InitialCredit/MoreCreditAfter of zero (#13067)

https://github.com/rabbitmq/rabbitmq-server/pull/13046
introduced additional checks which prevent setting
`{credit_flow_default_credit,{0,0}}`.

Setting credits to zero allows disabling the credit flow mechanism
(we use it in our benchmarks and mention for example in
https://www.rabbitmq.com/blog/2023/03/21/native-mqtt)

(cherry picked from commit a4634d3f7062544961e95a5498d62008d163f293)
---
 deps/rabbit/src/rabbit.erl | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/deps/rabbit/src/rabbit.erl b/deps/rabbit/src/rabbit.erl
index 6e5d95d79297..c5b0eaaed26c 100644
--- a/deps/rabbit/src/rabbit.erl
+++ b/deps/rabbit/src/rabbit.erl
@@ -1761,8 +1761,8 @@ persist_static_configuration() ->
                      {ok, {InitialCredit, MoreCreditAfter}}
                        when is_integer(InitialCredit) andalso
                             is_integer(MoreCreditAfter) andalso
-                            InitialCredit > 0 andalso
-                            MoreCreditAfter > 0 andalso
+                            InitialCredit >= 0 andalso
+                            MoreCreditAfter >= 0 andalso
                             MoreCreditAfter =< InitialCredit ->
                          {InitialCredit, MoreCreditAfter};
                      Other ->