Unclean shutdown on SIGINT / SIGTERM (#3308)

* libs/common: TrapSignal accepts logger as a first parameter

 and does not block anymore
* previously it was dumping "captured ..." msg to os.Stdout
* TrapSignal should not be responsible for blocking thread of execution

Refs #3238

* exit with zero (0) code upon receiving SIGTERM/SIGINT

Refs #3238

* fix formatting in docs/app-dev/abci-cli.md

Co-Authored-By: melekes <anton.kalyaev@gmail.com>

* fix formatting in docs/app-dev/abci-cli.md

Co-Authored-By: melekes <anton.kalyaev@gmail.com>

cmd/tendermint/commands/run_node.go

@@ -2,12 +2,10 @@ package commands
 
 import (
 	"fmt"
-	"os"
-	"os/signal"
-	"syscall"
 
 	"github.com/spf13/cobra"
 
+	cmn "github.com/tendermint/tendermint/libs/common"
 	nm "github.com/tendermint/tendermint/node"
 )
 
@@ -57,25 +55,19 @@ func NewRunNodeCmd(nodeProvider nm.NodeProvider) *cobra.Command {
 				return fmt.Errorf("Failed to create node: %v", err)
 			}
 
-			// Stop upon receiving SIGTERM or CTRL-C
-			c := make(chan os.Signal, 1)
-			signal.Notify(c, os.Interrupt, syscall.SIGTERM)
-			go func() {
-				for sig := range c {
-					logger.Error(fmt.Sprintf("captured %v, exiting...", sig))
-					if n.IsRunning() {
-						n.Stop()
-					}
-					os.Exit(1)
+			// Stop upon receiving SIGTERM or CTRL-C.
+			cmn.TrapSignal(logger, func() {
+				if n.IsRunning() {
+					n.Stop()
 				}
-			}()
+			})
 
 			if err := n.Start(); err != nil {
 				return fmt.Errorf("Failed to start node: %v", err)
 			}
 			logger.Info("Started node", "nodeInfo", n.Switch().NodeInfo())
 
-			// Run forever
+			// Run forever.
 			select {}
 		},
 	}