From 3db261d45bab46759f4049675483633822b1d090 Mon Sep 17 00:00:00 2001
From: James Clampffer <james.clampffer@hp.com>
Date: Mon, 10 Jul 2017 14:23:13 -0400
Subject: [PATCH] HDFS-12103: libhdfs++: Provide workaround to support cancel
 on filesystem connect until HDFS-11437 is resolved.  Contributed by James
 Clampffer.

---
 .../src/main/native/libhdfspp/lib/fs/filesystem.cc     | 10 ++++++----
 .../src/main/native/libhdfspp/lib/rpc/rpc_engine.cc    |  4 +++-
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/libhdfspp/lib/fs/filesystem.cc b/hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/libhdfspp/lib/fs/filesystem.cc
index 9ef3aa0950..761ff86076 100644
--- a/hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/libhdfspp/lib/fs/filesystem.cc
+++ b/hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/libhdfspp/lib/fs/filesystem.cc
@@ -288,14 +288,16 @@ int FileSystemImpl::WorkerThreadCount() {
 }
 
 bool FileSystemImpl::CancelPendingConnect() {
+  if(connect_callback_.IsCallbackAccessed()) {
+    // Temp fix for failover hangs, allow CancelPendingConnect to be called so it can push a flag through the RPC engine
+    LOG_DEBUG(kFileSystem, << "FileSystemImpl@" << this << "::CancelPendingConnect called after Connect completed");
+    return nn_.CancelPendingConnect();
+  }
+
   if(!connect_callback_.IsCallbackSet()) {
     LOG_DEBUG(kFileSystem, << "FileSystemImpl@" << this << "::CancelPendingConnect called before Connect started");
     return false;
   }
-  if(connect_callback_.IsCallbackAccessed()) {
-    LOG_DEBUG(kFileSystem, << "FileSystemImpl@" << this << "::CancelPendingConnect called after Connect completed");
-    return false;
-  }
 
   // First invoke callback, then do proper teardown in RpcEngine and RpcConnection
   ConnectCallback noop_callback = [](const Status &stat, FileSystem *fs) {
diff --git a/hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/libhdfspp/lib/rpc/rpc_engine.cc b/hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/libhdfspp/lib/rpc/rpc_engine.cc
index 98c41dad1f..ba5556531f 100644
--- a/hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/libhdfspp/lib/rpc/rpc_engine.cc
+++ b/hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/libhdfspp/lib/rpc/rpc_engine.cc
@@ -220,7 +220,9 @@ void RpcEngine::RpcCommsError(
 
     RetryAction retry = RetryAction::fail(""); // Default to fail
 
-    if (status.notWorthRetry()) {
+    if(connect_canceled_) {
+      retry = RetryAction::fail("Operation canceled");
+    } else if (status.notWorthRetry()) {
       retry = RetryAction::fail(status.ToString().c_str());
     } else if (retry_policy()) {
       retry = retry_policy()->ShouldRetry(status, req->IncrementRetryCount(), req->get_failover_count(), true);