Remove memstat and cmdline defaults

Author: mohanson

cmd/daze/main.go

@@ -1,6 +1,8 @@
 package main
 
 import (
+	"encoding/json"
+	"expvar"
 	"flag"
 	"fmt"
 	"log"
@@ -61,6 +63,31 @@ func main() {
 	if os.Getenv("ANDROID_ROOT") != "" {
 		net.DefaultResolver = daze.ResolverDns("1.1.1.1:53")
 	}
+	// Remove cmdline and memstats from expvar default exports.
+	// See: https://github.com/golang/go/issues/29105
+	muxHttp := http.NewServeMux()
+	muxHttp.HandleFunc("/debug/vars", func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json; charset=utf-8")
+		vars := new(expvar.Map).Init()
+		expvar.Do(func(kv expvar.KeyValue) {
+			vars.Set(kv.Key, kv.Value)
+		})
+		vars.Delete("cmdline")
+		vars.Delete("memstats")
+		msg := map[string]any{}
+		err := json.Unmarshal([]byte(vars.String()), &msg)
+		if err != nil {
+			w.WriteHeader(http.StatusBadRequest)
+			w.Write([]byte(err.Error()))
+			return
+		}
+		enc := json.NewEncoder(w)
+		enc.SetIndent("", "    ")
+		enc.Encode(msg)
+	})
+	muxHttp.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+		http.DefaultServeMux.ServeHTTP(w, r)
+	})
 	resExec := filepath.Dir(doa.Try(os.Executable()))
 	subCommand := os.Args[1]
 	os.Args = os.Args[1:len(os.Args)]
@@ -121,7 +148,7 @@ func main() {
 		if *flGpprof != "" {
 			_ = pprof.Handler
 			log.Println("main: listen net/http/pprof on", *flGpprof)
-			go func() { doa.Nil(http.ListenAndServe(*flGpprof, nil)) }()
+			go func() { doa.Nil(http.ListenAndServe(*flGpprof, muxHttp)) }()
 		}
 		// Hang prevent program from exiting.
 		gracefulexit.Wait()
@@ -199,7 +226,7 @@ func main() {
 		if *flGpprof != "" {
 			_ = pprof.Handler
 			log.Println("main: listen net/http/pprof on", *flGpprof)
-			go func() { doa.Nil(http.ListenAndServe(*flGpprof, nil)) }()
+			go func() { doa.Nil(http.ListenAndServe(*flGpprof, muxHttp)) }()
 		}
 		// Hang prevent program from exiting.
 		gracefulexit.Wait()