Move ReadConfigFileOnSighup to gobgpd main

Reloading the config file on SIGHUP is behavior specific to gobgpd.
Attempts to expose it through the config API was awkward and could
make the api more confusing to use. This change moves that
functionality up into the gobgpd main and out of the library.

3 files changed, 30 insertions, 54 deletions

diff --git a/cmd/gobgpd/main.go b/cmd/gobgpd/main.go
index 794d6e10..1bdcb449 100644
--- a/cmd/gobgpd/main.go
+++ b/cmd/gobgpd/main.go
@@ -168,17 +168,41 @@ func main() {
 		return
 	}
 
-	configCh := config.ReadConfigFileOnSighup(opts.ConfigFile, opts.ConfigType)
+	signal.Notify(sigCh, syscall.SIGHUP)
 
 	loop := func() {
-		initialConfig := <-configCh
+		initialConfig, err := config.ReadConfigFile(opts.ConfigFile, opts.ConfigType)
+		if err != nil {
+			log.WithFields(log.Fields{
+				"Topic": "Config",
+				"Error": err,
+			}).Fatalf("Can't read config file %s", opts.ConfigFile)
+		}
+		log.WithFields(log.Fields{
+			"Topic": "Config",
+		}).Info("Finished reading the config file")
+
 		c := config.ApplyInitialConfig(bgpServer, initialConfig, opts.GracefulRestart)
 		for {
 			select {
-			case <-sigCh:
-				stopServer(bgpServer, opts.UseSdNotify)
-				return
-			case newConfig := <-configCh:
+			case sig := <-sigCh:
+				if sig != syscall.SIGHUP {
+					stopServer(bgpServer, opts.UseSdNotify)
+					return
+				}
+
+				log.WithFields(log.Fields{
+					"Topic": "Config",
+				}).Info("Reload the config file")
+				newConfig, err := config.ReadConfigFile(opts.ConfigFile, opts.ConfigType)
+				if err != nil {
+					log.WithFields(log.Fields{
+						"Topic": "Config",
+						"Error": err,
+					}).Warningf("Can't read config file %s", opts.ConfigFile)
+					continue
+				}
+
 				c = config.UpdateConfig(bgpServer, c, newConfig)
 			}
 		}
diff --git a/internal/pkg/config/serve.go b/internal/pkg/config/serve.go
index c1525525..1fe71332 100644
--- a/internal/pkg/config/serve.go
+++ b/internal/pkg/config/serve.go
@@ -1,10 +1,6 @@
 package config
 
 import (
-	"os"
-	"os/signal"
-	"syscall"
-
 	log "github.com/sirupsen/logrus"
 	"github.com/spf13/viper"
 )
@@ -45,44 +41,6 @@ func ReadConfigfile(path, format string) (*BgpConfigSet, error) {
 	return config, nil
 }
 
-func ReadConfigfileServe(path, format string, configCh chan *BgpConfigSet) {
-	sigCh := make(chan os.Signal, 1)
-	signal.Notify(sigCh, syscall.SIGHUP)
-
-	cnt := 0
-	for {
-		c, err := ReadConfigfile(path, format)
-		if err != nil {
-			goto ERROR
-		}
-		if cnt == 0 {
-			log.WithFields(log.Fields{
-				"Topic": "Config",
-			}).Info("Finished reading the config file")
-		}
-		cnt++
-		configCh <- c
-		goto NEXT
-	ERROR:
-		if cnt == 0 {
-			log.WithFields(log.Fields{
-				"Topic": "Config",
-				"Error": err,
-			}).Fatalf("Can't read config file %s", path)
-		} else {
-			log.WithFields(log.Fields{
-				"Topic": "Config",
-				"Error": err,
-			}).Warningf("Can't read config file %s", path)
-		}
-	NEXT:
-		<-sigCh
-		log.WithFields(log.Fields{
-			"Topic": "Config",
-		}).Info("Reload the config file")
-	}
-}
-
 func ConfigSetToRoutingPolicy(c *BgpConfigSet) *RoutingPolicy {
 	return &RoutingPolicy{
 		DefinedSets:       c.DefinedSets,
diff --git a/pkg/config/config.go b/pkg/config/config.go
index e6ef0d20..b369760b 100644
--- a/pkg/config/config.go
+++ b/pkg/config/config.go
@@ -17,12 +17,6 @@ func ReadConfigFile(configFile, configType string) (*config.BgpConfigSet, error)
 	return config.ReadConfigfile(configFile, configType)
 }
 
-func ReadConfigFileOnSighup(configFile, configType string) chan *config.BgpConfigSet {
-	ch := make(chan *config.BgpConfigSet)
-	go config.ReadConfigfileServe(configFile, configType, ch)
-	return ch
-}
-
 func marshalRouteTargets(l []string) ([]*any.Any, error) {
 	rtList := make([]*any.Any, 0, len(l))
 	for _, rtString := range l {