added trace package

x/trace/trace.go

@@ -0,0 +1,53 @@
+package trace
+
+import (
+	"context"
+	"crypto/tls"
+
+	"golang.org/x/net/dns/dnsmessage"
+)
+
+type DNSClientTrace struct {
+	QuestionSent func(question dnsmessage.Question)
+	ResponsDone  func(question dnsmessage.Question, response *dnsmessage.Message, err error)
+	ConnectDone  func(network, addr string, err error)
+	WroteDone    func(err error)
+	ReadDone     func(err error)
+}
+
+type contextKey struct{}
+
+var dnsClientTraceKey = contextKey{}
+
+// WithDNSClientTrace adds DNS trace information to the context.
+func WithDNSClientTrace(ctx context.Context, trace *DNSClientTrace) context.Context {
+	return context.WithValue(ctx, dnsClientTraceKey, trace)
+}
+
+// GetDNSClientTrace retrieves the DNS trace information from the context, if available.
+func GetDNSClientTrace(ctx context.Context) *DNSClientTrace {
+	if trace, ok := ctx.Value(dnsClientTraceKey).(*DNSClientTrace); ok {
+		return trace
+	}
+	return nil
+}
+
+type TLSClientTrace struct {
+	TLSHandshakeStart func()
+	TLSHandshakeDone  func(state tls.ConnectionState, err error)
+}
+
+var tlsClientTraceKey = contextKey{}
+
+// WithTLSClientTrace adds TLS trace information to the context.
+func WithTLSClientTrace(ctx context.Context, trace *TLSClientTrace) context.Context {
+	return context.WithValue(ctx, tlsClientTraceKey, trace)
+}
+
+// GetTLSClientTrace retrieves the TLS trace information from the context, if available.
+func GetTLSClientTrace(ctx context.Context) *TLSClientTrace {
+	if trace, ok := ctx.Value(tlsClientTraceKey).(*TLSClientTrace); ok {
+		return trace
+	}
+	return nil
+}