added getConfig

cmd/ipfs/ipfs.go

 package main
 
 import (
-	"errors"
 	"fmt"
 	"os"
 	"runtime/pprof"
@@ -106,17 +105,30 @@ func localNode(confdir string, online bool) (*core.IpfsNode, error) {
 // Gets the config "-c" flag from the command, or returns
 // the default configuration root directory
 func getConfigDir(c *commander.Command) (string, error) {
-	conf := c.Flag.Lookup("c").Value.Get()
-	if conf == nil {
-		return config.PathRoot()
+
+	// use the root cmd (that's where config is specified)
+	for ; c.Parent != nil; c = c.Parent {
 	}
-	confStr, ok := conf.(string)
-	if !ok {
-		return "", errors.New("failed to retrieve config flag value.")
+
+	// flag should be defined on root.
+	param := c.Flag.Lookup("c").Value.Get().(string)
+	if param != "" {
+		return u.TildeExpansion(param)
 	}
-	if len(confStr) == 0 {
+
 	return config.PathRoot()
+}
+
+func getConfig(c *commander.Command) (*config.Config, error) {
+	confdir, err := getConfigDir(c)
+	if err != nil {
+		return nil, err
+	}
+
+	filename, err := config.Filename(confdir)
+	if err != nil {
+		return nil, err
 	}
 
-	return u.TildeExpansion(confStr)
+	return config.Load(filename)
 }