From a197c864e874008b32c70c59e2cc2a2ad7e40486 Mon Sep 17 00:00:00 2001
From: Sergey Frolov <sfrolov@google.com>
Date: Thu, 27 Jul 2017 17:01:40 -0400
Subject: [PATCH] Move fallbackHosts to vhostTrie

---
 caddyhttp/httpserver/server.go     | 11 +++++++++++
 caddyhttp/httpserver/siteconfig.go |  3 +++
 caddyhttp/httpserver/vhosttrie.go  | 17 ++++++-----------
 3 files changed, 20 insertions(+), 11 deletions(-)

diff --git a/caddyhttp/httpserver/server.go b/caddyhttp/httpserver/server.go
index f4f22ab5..c91212ae 100644
--- a/caddyhttp/httpserver/server.go
+++ b/caddyhttp/httpserver/server.go
@@ -57,6 +57,16 @@ func makeTLSConfig(group []*SiteConfig) (*tls.Config, error) {
 	return caddytls.MakeTLSConfig(tlsConfigs)
 }
 
+func getFallbacks(sites []*SiteConfig) []string {
+	fallbacks := []string{}
+	for _, sc := range sites {
+		if sc.FallbackSite {
+			fallbacks = append(fallbacks, sc.Addr.Host)
+		}
+	}
+	return fallbacks
+}
+
 // NewServer creates a new Server instance that will listen on addr
 // and will serve the sites configured in group.
 func NewServer(addr string, group []*SiteConfig) (*Server, error) {
@@ -66,6 +76,7 @@ func NewServer(addr string, group []*SiteConfig) (*Server, error) {
 		sites:       group,
 		connTimeout: GracefulTimeout,
 	}
+	s.vhosts.fallbackHosts = append(s.vhosts.fallbackHosts, getFallbacks(group)...)
 	s.Server = makeHTTPServerWithHeaderLimit(s.Server, group)
 	s.Server.Handler = s // this is weird, but whatever
 
diff --git a/caddyhttp/httpserver/siteconfig.go b/caddyhttp/httpserver/siteconfig.go
index a091868f..9f17122c 100644
--- a/caddyhttp/httpserver/siteconfig.go
+++ b/caddyhttp/httpserver/siteconfig.go
@@ -52,6 +52,9 @@ type SiteConfig struct {
 	// preserving functionality needed for proxying,
 	// websockets, etc.
 	Timeouts Timeouts
+
+	// If true all unmatched requests will be served by this site
+	FallbackSite bool
 }
 
 // Timeouts specify various timeouts for a server to use.
diff --git a/caddyhttp/httpserver/vhosttrie.go b/caddyhttp/httpserver/vhosttrie.go
index 4023d034..d4934707 100644
--- a/caddyhttp/httpserver/vhosttrie.go
+++ b/caddyhttp/httpserver/vhosttrie.go
@@ -10,14 +10,15 @@ import (
 // wildcards as TLS certificates support them), then
 // by longest matching path.
 type vhostTrie struct {
-	edges map[string]*vhostTrie
-	site  *SiteConfig // site to match on this node; also known as a virtual host
-	path  string      // the path portion of the key for the associated site
+	fallbackHosts []string
+	edges         map[string]*vhostTrie
+	site          *SiteConfig // site to match on this node; also known as a virtual host
+	path          string      // the path portion of the key for the associated site
 }
 
 // newVHostTrie returns a new vhostTrie.
 func newVHostTrie() *vhostTrie {
-	return &vhostTrie{edges: make(map[string]*vhostTrie)}
+	return &vhostTrie{edges: make(map[string]*vhostTrie), fallbackHosts: []string{"0.0.0.0", ""}}
 }
 
 // Insert adds stack to t keyed by key. The key should be
@@ -45,12 +46,6 @@ func (t *vhostTrie) insertPath(remainingPath, originalPath string, site *SiteCon
 	t.edges[ch].insertPath(remainingPath[1:], originalPath, site)
 }
 
-// When matching a site, the given host will be tried first.
-// Then, FallbackHosts will be tried in order.
-// Default FallbackHosts are following wildcards,
-// which could be modified by plugins and directives.
-var FallbackHosts = []string{"0.0.0.0", ""}
-
 // Match returns the virtual host (site) in v with
 // the closest match to key. If there was a match,
 // it returns the SiteConfig and the path portion of
@@ -65,7 +60,7 @@ func (t *vhostTrie) Match(key string) (*SiteConfig, string) {
 	host, path := t.splitHostPath(key)
 	// try the given host, then, if no match, try fallback hosts
 	branch := t.matchHost(host)
-	for _, h := range FallbackHosts {
+	for _, h := range t.fallbackHosts {
 		if branch != nil {
 			break
 		}