mox!

smtp/path.go

@@ -0,0 +1,67 @@
+package smtp
+
+import (
+	"strings"
+
+	"github.com/mjl-/mox/dns"
+)
+
+// Path is an SMTP forward/reverse path, as used in MAIL FROM and RCPT TO
+// commands.
+type Path struct {
+	Localpart Localpart
+	IPDomain  dns.IPDomain
+}
+
+func (p Path) IsZero() bool {
+	return p.Localpart == "" && p.IPDomain.IsZero()
+}
+
+// String returns a string representation with ASCII-only domain name.
+func (p Path) String() string {
+	return p.XString(false)
+}
+
+// XString is like String, but returns unicode UTF-8 domain names if utf8 is
+// true.
+func (p Path) XString(utf8 bool) string {
+	if p.Localpart == "" && p.IPDomain.IsZero() {
+		return ""
+	}
+	return p.Localpart.String() + "@" + p.IPDomain.XString(utf8)
+}
+
+// ASCIIExtra returns an ascii-only path if utf8 is true and the ipdomain is a
+// unicode domain. Otherwise returns an empty string.
+//
+// For use in comments in message headers added during SMTP.
+func (p Path) ASCIIExtra(utf8 bool) string {
+	if utf8 && p.IPDomain.Domain.Unicode != "" {
+		return p.XString(false)
+	}
+	return ""
+}
+
+// DSNString returns a string representation as used with DSN with/without
+// UTF-8 support.
+//
+// If utf8 is false, the domain is represented as US-ASCII (IDNA), and the
+// localpart is encoded with in 7bit according to RFC 6533.
+func (p Path) DSNString(utf8 bool) string {
+	if utf8 {
+		return p.XString(utf8)
+	}
+	return p.Localpart.DSNString(utf8) + "@" + p.IPDomain.XString(utf8)
+}
+
+func (p Path) Equal(o Path) bool {
+	if p.Localpart != o.Localpart {
+		return false
+	}
+	d0 := p.IPDomain
+	d1 := o.IPDomain
+	if len(d0.IP) > 0 || len(d1.IP) > 0 {
+		return d0.IP.Equal(d1.IP)
+	}
+	return strings.EqualFold(d0.Domain.ASCII, d1.Domain.ASCII)
+}