Use shared func for registering Sigterm on a context (#799)

cmd/agent/agent.go

@@ -35,6 +35,7 @@ import (
 	"github.com/woodpecker-ci/woodpecker/agent"
 	"github.com/woodpecker-ci/woodpecker/pipeline/backend"
 	"github.com/woodpecker-ci/woodpecker/pipeline/rpc"
+	"github.com/woodpecker-ci/woodpecker/shared/utils"
 )
 
 func loop(c *cli.Context) error {
@@ -119,7 +120,7 @@ func loop(c *cli.Context) error {
 		context.Background(),
 		metadata.Pairs("hostname", hostname),
 	)
-	ctx = WithContextFunc(ctx, func() {
+	ctx = utils.WithContextSigtermCallback(ctx, func() {
 		println("ctrl+c received, terminating process")
 		sigterm.Set()
 	})

cmd/agent/signal.go

@@ -1,34 +0,0 @@
-// Copyright 2017 Drone.IO Inc.
-//
-// This file is licensed under the terms of the MIT license.
-// For a copy, see https://opensource.org/licenses/MIT.
-
-package main
-
-import (
-	"context"
-	"os"
-	"os/signal"
-	"syscall"
-)
-
-// WithContextFunc returns a copy of parent context that is canceled when
-// an os interrupt signal is received. The callback function f is invoked
-// before cancellation.
-func WithContextFunc(ctx context.Context, f func()) context.Context {
-	ctx, cancel := context.WithCancel(ctx)
-	go func() {
-		c := make(chan os.Signal, 1)
-		signal.Notify(c, syscall.SIGINT, syscall.SIGTERM)
-		defer signal.Stop(c)
-
-		select {
-		case <-ctx.Done():
-		case <-c:
-			f()
-			cancel()
-		}
-	}()
-
-	return ctx
-}