From 9e6c23d9af99b5b85379b0fc6af205e8d3d22742 Mon Sep 17 00:00:00 2001
From: Nick Craig-Wood <nick@craig-wood.com>
Date: Mon, 19 Apr 2021 17:00:07 +0100
Subject: [PATCH] fs: add --disable-http2 for global http2 disable #5253

---
 fs/config.go                         | 1 +
 fs/config/configflags/configflags.go | 1 +
 fs/fshttp/http.go                    | 4 ++++
 3 files changed, 6 insertions(+)

diff --git a/fs/config.go b/fs/config.go
index 0e3ce187d..eece951f8 100644
--- a/fs/config.go
+++ b/fs/config.go
@@ -125,6 +125,7 @@ type ConfigInfo struct {
 	TrafficClass           uint8
 	FsCacheExpireDuration  time.Duration
 	FsCacheExpireInterval  time.Duration
+	DisableHTTP2           bool
 }
 
 // NewConfig creates a new config with everything set to the default
diff --git a/fs/config/configflags/configflags.go b/fs/config/configflags/configflags.go
index 7a00c14f1..62098835b 100644
--- a/fs/config/configflags/configflags.go
+++ b/fs/config/configflags/configflags.go
@@ -130,6 +130,7 @@ func AddFlags(ci *fs.ConfigInfo, flagSet *pflag.FlagSet) {
 	flags.StringVarP(flagSet, &dscp, "dscp", "", "", "Set DSCP value to connections. Can be value or names, eg. CS1, LE, DF, AF21.")
 	flags.DurationVarP(flagSet, &ci.FsCacheExpireDuration, "fs-cache-expire-duration", "", ci.FsCacheExpireDuration, "cache remotes for this long (0 to disable caching)")
 	flags.DurationVarP(flagSet, &ci.FsCacheExpireInterval, "fs-cache-expire-interval", "", ci.FsCacheExpireInterval, "interval to check for expired remotes")
+	flags.BoolVarP(flagSet, &ci.DisableHTTP2, "disable-http2", "", ci.DisableHTTP2, "Disable HTTP/2 in the global transport.")
 }
 
 // ParseHeaders converts the strings passed in via the header flags into HTTPOptions
diff --git a/fs/fshttp/http.go b/fs/fshttp/http.go
index fb8e6945d..b2b72bb99 100644
--- a/fs/fshttp/http.go
+++ b/fs/fshttp/http.go
@@ -100,6 +100,10 @@ func NewTransportCustom(ctx context.Context, customize func(*http.Transport)) ht
 			" the body of the request will be gunzipped before showing it.")
 	}
 
+	if ci.DisableHTTP2 {
+		t.TLSNextProto = map[string]func(string, *tls.Conn) http.RoundTripper{}
+	}
+
 	// customize the transport if required
 	if customize != nil {
 		customize(t)