logging: disable unless DEBUG environmental variable is not empty (re…

…solves namecoin#23)

main.go

@@ -34,29 +34,39 @@ package main
 import "C"
 
 import (
-	"io"
-	"unsafe"
+	"io/ioutil"
 	"log"
 	"os"
+	"path/filepath"
+	"unsafe"
 )
 
-var logfile io.Closer
 var backend Backend
 
+var debug = os.Getenv("DEBUG") != ""
+
 func init() {
-	f, err := os.OpenFile(os.Getenv("HOME")+"/testlogfile", os.O_RDWR|os.O_CREATE|os.O_APPEND, 0600)
-	if err != nil {
-		log.Fatalf("error opening file: %v", err)
+	log.SetOutput(ioutil.Discard)
+	if debug {
+		f, err := os.OpenFile(filepath.Join(os.Getenv("HOME"), "ncp11.log"), os.O_RDWR|os.O_CREATE|os.O_APPEND, 0600)
+		if err != nil {
+			log.Printf("error opening file: %v", err)
+			return
+		}
+		log.SetOutput(f)
+		log.Println("Namecoin PKCS#11 module loading")
 	}
-	log.SetOutput(f)
-	logfile = f
-	log.Println("Namecoin PKCS#11 module loading")
+}
 
+func init() {
 	backend = BackendNamecoin{}
 }
 
 //export GoLog
 func GoLog(s unsafe.Pointer) {
+	if debug {
+		return
+	}
 	log.Println(C.GoString((*C.char)(s)))
 }
 
@@ -77,8 +87,8 @@ func Go_GetInfo(p C.CK_INFO_PTR) C.CK_RV {
 	// TODO: Packing on Windows may break in this function.  Should we be
 	// using C.ckInfo here?
 
-	if (p == nil) {
-		return C.CKR_ARGUMENTS_BAD;
+	if p == nil {
+		return C.CKR_ARGUMENTS_BAD
 	}
 
 	info, err := backend.GetInfo()