From baf0d2f304f24842464be5d612d6faea6ccf0509 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E8=80=81=E4=B9=9D?= <366193849@qq.com>
Date: Fri, 3 Dec 2021 23:26:59 +0800
Subject: [PATCH] release semaphore

---
 FastGithub.DomainResolve/DnsClient.cs | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/FastGithub.DomainResolve/DnsClient.cs b/FastGithub.DomainResolve/DnsClient.cs
index 162f34c..e96bc88 100644
--- a/FastGithub.DomainResolve/DnsClient.cs
+++ b/FastGithub.DomainResolve/DnsClient.cs
@@ -117,9 +117,9 @@ namespace FastGithub.DomainResolve
                 return true;
             }
 
-            if (this.dnsStateCache.TryGetValue<bool>(dns, out var state))
+            if (this.dnsStateCache.TryGetValue<bool>(dns, out var available))
             {
-                return state;
+                return available;
             }
 
             var key = dns.ToString();
@@ -139,6 +139,10 @@ namespace FastGithub.DomainResolve
                 cancellationToken.ThrowIfCancellationRequested();
                 return this.dnsStateCache.Set(dns, false, this.stateExpiration);
             }
+            finally
+            {
+                semaphore.Release();
+            }
         }
 
         /// <summary>