From 0fb8504b20952905d050e3c37a071a53eea939e0 Mon Sep 17 00:00:00 2001
From: Andy Green <andy@warmcat.com>
Date: Fri, 26 Jun 2020 09:58:20 +0100
Subject: [PATCH] client: suppress CONNECTION_ERROR if still in
 client_connect_via_info

If the client connection attempt fails early, we report it will a NULL
return from the client connection api.  If it fails later, perhaps after
more times around the event loop, we report it as a CONNECTION_ERROR.

This patch makes sure we don't do CONNECTION_ERROR flow if in fact we
are still in the client_connect_via_info() and in a position to report
the failure by returning NULL from there, without it under some
conditions we will do both a CONNECTION_ERROR and return NULL.
---
 lib/core-net/close.c                |  7 ++++---
 lib/core-net/connect.c              | 15 ++++++++++++++-
 lib/core-net/private-lib-core-net.h |  3 +++
 3 files changed, 21 insertions(+), 4 deletions(-)

diff --git a/lib/core-net/close.c b/lib/core-net/close.c
index f10cea428..a92f258fe 100644
--- a/lib/core-net/close.c
+++ b/lib/core-net/close.c
@@ -214,9 +214,10 @@ lws_inform_client_conn_fail(struct lws *wsi, void *arg, size_t len)
 	if (!wsi->protocol)
 		return;
 
-	wsi->protocol->callback(wsi,
-			        LWS_CALLBACK_CLIENT_CONNECTION_ERROR,
-				wsi->user_space, arg, len);
+	if (!wsi->client_suppress_CONNECTION_ERROR)
+		wsi->protocol->callback(wsi,
+					LWS_CALLBACK_CLIENT_CONNECTION_ERROR,
+					wsi->user_space, arg, len);
 }
 #endif
 
diff --git a/lib/core-net/connect.c b/lib/core-net/connect.c
index af5c9a9d2..1fae6c799 100644
--- a/lib/core-net/connect.c
+++ b/lib/core-net/connect.c
@@ -58,6 +58,12 @@ lws_client_connect_via_info(const struct lws_client_connect_info *i)
 	if (wsi == NULL)
 		goto bail;
 
+	/*
+	 * Until we exit, we can report connection failure directly to the
+	 * caller without needing to call through to protocol CONNECTION_ERROR.
+	 */
+	wsi->client_suppress_CONNECTION_ERROR = 1;
+
 	if (i->keep_warm_secs)
 		wsi->keep_warm_secs = i->keep_warm_secs;
 	else
@@ -356,9 +362,16 @@ lws_client_connect_via_info(const struct lws_client_connect_info *i)
 
 		/* fallthru */
 
-		lws_http_client_connect_via_info2(wsi);
+		wsi = lws_http_client_connect_via_info2(wsi);
 	}
 
+	if (wsi)
+		/*
+		 * If it subsequently fails, report CONNECTION_ERROR,
+		 * because we're going to return a non-error return now.
+		 */
+		wsi->client_suppress_CONNECTION_ERROR = 0;
+
 	return wsi;
 
 #if defined(LWS_WITH_TLS)
diff --git a/lib/core-net/private-lib-core-net.h b/lib/core-net/private-lib-core-net.h
index 065b25264..a688e03b5 100644
--- a/lib/core-net/private-lib-core-net.h
+++ b/lib/core-net/private-lib-core-net.h
@@ -823,6 +823,9 @@ struct lws {
 	unsigned int			client_mux_migrated:1;
 	unsigned int			client_subsequent_mime_part:1;
 	unsigned int                    client_no_follow_redirect:1;
+	unsigned int                    client_suppress_CONNECTION_ERROR:1;
+	/**< because the client connection creation api is still the parent of
+	 * this activity, and will report the failure */
 #endif
 
 #ifdef _WIN32