From f09713bc19eb3a447e50d8309d13635982e4cf5f Mon Sep 17 00:00:00 2001
From: Orvaxis <198349614+Orvaxis@users.noreply.github.com>
Date: Thu, 9 Oct 2025 13:02:58 +0800
Subject: [PATCH] fix: respect receiver's window size in send buffer full check

---
 src/stream/tcb.rs | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/stream/tcb.rs b/src/stream/tcb.rs
index 202a9a1..7795447 100644
--- a/src/stream/tcb.rs
+++ b/src/stream/tcb.rs
@@ -300,7 +300,9 @@ impl Tcb {
     }
 
     pub fn is_send_buffer_full(&self) -> bool {
-        self.seq.distance(self.get_last_received_ack()) >= MAX_UNACK
+        // To respect the receiver's window (remote_window) size and avoid sending too many unacknowledged packets, which may cause packet loss
+        // Simplified version: min(cwnd, rwnd)
+        self.seq.distance(self.get_last_received_ack()) >= MAX_UNACK.min(self.get_send_window() as u32)
     }
 }