From bbef8780fd72c803273984dd250c0e45fa584c7a Mon Sep 17 00:00:00 2001
From: ihmc3jn09hk <ihmc3jn09hk@yahoo.com.hk>
Date: Sat, 6 Jun 2020 12:59:54 +0800
Subject: [PATCH] Fix a bug in ListenerManager::getIOLoop() (#461)

Co-authored-by: antao <antao2002@gmail.com>
---
 lib/src/ListenerManager.cc | 22 ++++++++++------------
 1 file changed, 10 insertions(+), 12 deletions(-)

diff --git a/lib/src/ListenerManager.cc b/lib/src/ListenerManager.cc
index fd01d851..4768b623 100644
--- a/lib/src/ListenerManager.cc
+++ b/lib/src/ListenerManager.cc
@@ -203,24 +203,22 @@ ListenerManager::~ListenerManager()
 
 trantor::EventLoop *ListenerManager::getIOLoop(size_t id) const
 {
-#ifdef __linux__
-    if (id >= listeningloopThreads_.size())
+    auto const n = listeningloopThreads_.size();
+    if (0 == n)
     {
-        LOG_TRACE << "Loop id (" << id << ") out of range [0-"
-                  << listeningloopThreads_.size() << ").";
-        id %= listeningloopThreads_.size();
+        LOG_WARN << "Please call getIOLoop() after drogon::app().run()";
+        return nullptr;
+    }
+    if (id >= n)
+    {
+        LOG_TRACE << "Loop id (" << id << ") out of range [0-" << n << ").";
+        id %= n;
         LOG_TRACE << "Rounded to : " << id;
     }
+#ifdef __linux__
     assert(listeningloopThreads_[id]);
     return listeningloopThreads_[id]->getLoop();
 #else
-    if (id >= ioLoopThreadPoolPtr_->size())
-    {
-        LOG_TRACE << "Loop id (" << id << ") out of range [0-"
-                  << listeningloopThreads_.size() << ").";
-        id %= ioLoopThreadPoolPtr_->size();
-        LOG_TRACE << "Rounded to : " << id;
-    }
     return ioLoopThreadPoolPtr_->getLoop(id);
 #endif
 }