pkg/tcpip: impl json.Marshaler/Unmarshaler for StatCounter to Marshal/Unmarshal *Stats

[ruokeqx]

[ayushr2]

This doesn't have any usages in gVisor codebase. If you are using the netstack package, maybe just define this in the client code? StatCounter is an exported type.

[ruokeqx]

This doesn't have any usages in gVisor codebase. If you are using the netstack package, maybe just define this in the client code? StatCounter is an exported type.

Hi.

Yes, I am indeed using the netstack package. I'm writing simple code like the following and want it to output JSON with the fields of Stats as keys and the corresponding values of StatCounter as values. However, the count filed of StatCounter is not exported and will generate empty JSON object {}. I cannot extend the implementation of StatCounter outside of the tcpip package.

Of course, i can write code like https://github.com/xjasonlyu/tun2socks/blob/main/restapi/netstats.go#L63-L96, but simple code is prefered.

Do you have any suggestions?

package main

import (
	"encoding/json"
	"fmt"
	"gvisor.dev/gvisor/pkg/tcpip/stack"
)

func main() {
	s := stack.New(stack.Options{})
	b, err := json.Marshal(s.Stats().TCP)
	if err != nil {
		panic(err)
	}
	fmt.Println(string(b))
}

[ayushr2]

Please squash your commits, all commits are applied to the master branch after merge.