improvement

quickfix/fileutil.go

@@ -0,0 +1,56 @@
+// Copyright (c) quickfixengine.org  All rights reserved.
+//
+// This file may be distributed under the terms of the quickfixengine.org
+// license as defined by quickfixengine.org and appearing in the file
+// LICENSE included in the packaging of this file.
+//
+// This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING
+// THE WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A
+// PARTICULAR PURPOSE.
+//
+// See http://www.quickfixengine.org/LICENSE for licensing information.
+//
+// Contact ask@quickfixengine.org if any conditions of this licensing
+// are not clear to you.
+
+package quickfix
+
+import (
+	"fmt"
+	"os"
+	"strings"
+)
+
+func sessionIDFilenamePrefix(s SessionID) string {
+	sender := []string{s.SenderCompID}
+	if s.SenderSubID != "" {
+		sender = append(sender, s.SenderSubID)
+	}
+	if s.SenderLocationID != "" {
+		sender = append(sender, s.SenderLocationID)
+	}
+
+	target := []string{s.TargetCompID}
+	if s.TargetSubID != "" {
+		target = append(target, s.TargetSubID)
+	}
+	if s.TargetLocationID != "" {
+		target = append(target, s.TargetLocationID)
+	}
+
+	fname := []string{s.BeginString, strings.Join(sender, "_"), strings.Join(target, "_")}
+	if s.Qualifier != "" {
+		fname = append(fname, s.Qualifier)
+	}
+	return strings.Join(fname, "-")
+}
+
+// openOrCreateFile opens a file for reading and writing, creating it if necessary.
+func openOrCreateFile(fname string, perm os.FileMode) (f *os.File, err error) {
+	if f, err = os.OpenFile(fname, os.O_RDWR, perm); err != nil {
+		if f, err = os.OpenFile(fname, os.O_RDWR|os.O_CREATE, perm); err != nil {
+			return nil, fmt.Errorf("error opening or creating file: %s: %s", fname, err.Error())
+		}
+	}
+	return f, nil
+}