Add Graceful shutdown for Windows and hooks for shutdown of goroutines (#8964)

* Graceful Shutdown for windows and others

Restructures modules/graceful, adding shutdown for windows, removing and
replacing the old minwinsvc code.

Creates a new waitGroup - terminate which allows for goroutines to
finish up after the shutdown of the servers.

Shutdown and terminate hooks are added for goroutines.

* Remove unused functions - these can be added in a different PR

* Add startup timeout functionality

* Document STARTUP_TIMEOUT

3 files changed, 4 insertions, 42 deletions

diff --git a/cmd/web.go b/cmd/web.go
index 3ca4041a7d..22a7f9082d 100644
--- a/cmd/web.go
+++ b/cmd/web.go
@@ -227,7 +227,8 @@ func runWeb(ctx *cli.Context) error {
 		log.Critical("Failed to start server: %v", err)
 	}
 	log.Info("HTTP Listener: %s Closed", listenAddr)
-	graceful.WaitForServers()
+	graceful.Manager.WaitForServers()
+	graceful.Manager.WaitForTerminate()
 	log.Close()
 	return nil
 }
diff --git a/cmd/web_graceful.go b/cmd/web_graceful.go
index 07b5a964c5..a37f669d09 100644
--- a/cmd/web_graceful.go
+++ b/cmd/web_graceful.go
@@ -1,5 +1,3 @@
-// +build !windows
-
 // Copyright 2016 The Gitea Authors. All rights reserved.
 // Use of this source code is governed by a MIT-style
 // license that can be found in the LICENSE file.
@@ -27,11 +25,11 @@ func runHTTPSWithTLSConfig(listenAddr string, tlsConfig *tls.Config, m http.Hand
 
 // NoHTTPRedirector tells our cleanup routine that we will not be using a fallback http redirector
 func NoHTTPRedirector() {
-	graceful.InformCleanup()
+	graceful.Manager.InformCleanup()
 }
 
 // NoMainListener tells our cleanup routine that we will not be using a possibly provided listener
 // for our main HTTP/HTTPS service
 func NoMainListener() {
-	graceful.InformCleanup()
+	graceful.Manager.InformCleanup()
 }
diff --git a/cmd/web_windows.go b/cmd/web_windows.go
deleted file mode 100644
index cdd2cc513b..0000000000
--- a/cmd/web_windows.go
+++ /dev/null
@@ -1,37 +0,0 @@
-// +build windows
-
-// Copyright 2016 The Gitea Authors. All rights reserved.
-// Use of this source code is governed by a MIT-style
-// license that can be found in the LICENSE file.
-
-package cmd
-
-import (
-	"crypto/tls"
-	"net/http"
-)
-
-func runHTTP(listenAddr string, m http.Handler) error {
-	return http.ListenAndServe(listenAddr, m)
-}
-
-func runHTTPS(listenAddr, certFile, keyFile string, m http.Handler) error {
-	return http.ListenAndServeTLS(listenAddr, certFile, keyFile, m)
-}
-
-func runHTTPSWithTLSConfig(listenAddr string, tlsConfig *tls.Config, m http.Handler) error {
-	server := &http.Server{
-		Addr:      listenAddr,
-		Handler:   m,
-		TLSConfig: tlsConfig,
-	}
-	return server.ListenAndServeTLS("", "")
-}
-
-// NoHTTPRedirector is a no-op on Windows
-func NoHTTPRedirector() {
-}
-
-// NoMainListener is a no-op on Windows
-func NoMainListener() {
-}