platform package for GOOS=wasip1

fs.go

package platform

import (
	"os"
	"path/filepath"
)

// ExecutableDir returns the directory containing the current executable,
// or when an error occurs, the current working directory.
func ExecutableDir() (string, error) {
	path, err := os.Executable()
	if err == nil {
		return filepath.Dir(path), nil
	}
	return os.Getwd()
}

net.go

package platform

import (
	"context"
	"net"
	"net/http"
)

func init() {
	// Ensure http.DefaultTransport uses our DialContext.
	if t, ok := http.DefaultTransport.(*http.Transport); ok {
		t.DialContext = DialContext
	}
}

// A ContextDialer implements the DialContext method, e.g. net.Dialer.
type ContextDialer interface {
	DialContext(ctx context.Context, network, addr string) (net.Conn, error)
}

type contextDialer struct{}

func (*contextDialer) DialContext(ctx context.Context, network, addr string) (net.Conn, error) {
	return DialContext(ctx, network, addr)
}

// DialerDefault is the default ContextDialer for other packages in this module.
var DialerDefault ContextDialer = &contextDialer{}

// DialContext opens a new net.Conn, optionally forcing IPv4.
func DialContext(ctx context.Context, network, addr string) (net.Conn, error) {
	network = filterNetwork(network)
	return dialContext(ctx, network, addr)
}

// Listen opens a net.Listener, , optionally forcing IPv4.
func Listen(network, addr string) (net.Listener, error) {
	network = filterNetwork(network)
	return listen(network, addr)
}

func filterNetwork(network string) string {
	if !ForceIPv4 {
		return network
	}
	switch network {
	case "tcp", "tcp6":
		return "tcp4"
	case "udp", "udp6":
		return "udp4"
	case "ip", "ip6":
		return "ip4"
	}
	return network
}

net_default.go

//go:build !wasip1

package platform

import "net"

const (
	// ForceIPv4 is set to false by default, to allow IPv6 networking.
	ForceIPv4 = false

	// TCP is set to "tcp" by default.
	// Certain platforms may elect to set this to "tcp4" or "tcp6".
	TCP = "tcp"

	// UDP is set to "udp" by default.
	// Certain platforms may elect to set this to "udp4" or "udp6".
	UDP = "udp"
)

// dialContext opens a new net.Conn.
var dialContext = (&net.Dialer{}).DialContext

// Listen opens a net.Listener.
var listen = net.Listen

net_wasip1.go

//go:build wasip1

package platform

import (
	"github.com/stealthrocket/net/wasip1"
)

const (
	// ForceIPv4 is set to true because Wazero/wasi-go doesn’t support IPv6.
	ForceIPv4 = true

	// TCP is set to "tcp4" because Wazero/wasi-go doesn’t support IPv6.
	TCP = "tcp4"

	// UDP is set to "udp4" because Wazero/wasi-go doesn’t support IPv6.
	UDP = "udp4"
)

// dialContext opens a new net.Conn.
var dialContext = wasip1.DialContext

// listen opens a net.Listener.
var listen = wasip1.Listen