Add cmd/sojuctl

This new command enables communicating with the unix administrative
endpoint (unix+admin) that can be enabled on soju.

The syntax is just that of BouncerServ.

Examples:
    sojuctl -config soju.config help
    sojuctl -config soju.config user status

Makefile

@@ -11,24 +11,26 @@ config_path := $(DESTDIR)/$(SYSCONFDIR)/soju/config
 goflags := $(GOFLAGS) \
 	-ldflags="-X 'git.sr.ht/~emersion/soju/config.DefaultPath=$(config_path)'"
 
-all: soju sojudb doc/soju.1
+all: soju sojudb sojuctl doc/soju.1
 
 soju:
 	$(GO) build $(goflags) ./cmd/soju
 sojudb:
 	$(GO) build $(goflags) ./cmd/sojudb
+sojuctl:
+	$(GO) build $(goflags) ./cmd/sojuctl
 doc/soju.1: doc/soju.1.scd
 	$(SCDOC) <doc/soju.1.scd >doc/soju.1
 
 clean:
-	$(RM) -f soju sojudb doc/soju.1
+	$(RM) -f soju sojudb sojuctl doc/soju.1
 install:
 	mkdir -p $(DESTDIR)$(PREFIX)/$(BINDIR)
 	mkdir -p $(DESTDIR)$(PREFIX)/$(MANDIR)/man1
 	mkdir -p $(DESTDIR)/$(SYSCONFDIR)/soju
 	mkdir -p $(DESTDIR)/var/lib/soju
-	cp -f soju sojudb $(DESTDIR)$(PREFIX)/$(BINDIR)
+	cp -f soju sojudb sojuctl $(DESTDIR)$(PREFIX)/$(BINDIR)
 	cp -f doc/soju.1 $(DESTDIR)$(PREFIX)/$(MANDIR)/man1
 	[ -f $(config_path) ] || cp -f config.in $(config_path)
 
-.PHONY: soju sojudb clean install
+.PHONY: soju sojudb sojuctl clean install

cmd/sojuctl/main.go

@@ -0,0 +1,110 @@
+package main
+
+import (
+	"context"
+	"flag"
+	"fmt"
+	"git.sr.ht/~emersion/soju"
+	"gopkg.in/irc.v4"
+	"log"
+	"net"
+	"net/url"
+	"strconv"
+	"strings"
+
+	"git.sr.ht/~emersion/soju/config"
+)
+
+const usage = `usage: sojuctl [-config path] <command>
+`
+
+func init() {
+	flag.Usage = func() {
+		fmt.Fprintf(flag.CommandLine.Output(), usage)
+	}
+}
+
+func run(ctx context.Context, cfg *config.Server, words []string) error {
+	var path string
+	for _, listen := range cfg.Listen {
+		u, err := url.Parse(listen)
+		if err != nil {
+			continue
+		}
+		if u.Scheme != "unix+admin" {
+			continue
+		}
+		if u.Path != "" {
+			path = u.Path
+		} else {
+			path = soju.DefaultUnixAdminPath
+		}
+		break
+	}
+	if path == "" {
+		return fmt.Errorf("no listen unix+admin directive found in config")
+	}
+	var d net.Dialer
+	uc, err := d.DialContext(ctx, "unix", path)
+	if err != nil {
+		return fmt.Errorf("dial %v: %v", path, err)
+	}
+	defer uc.Close()
+	c := irc.NewConn(uc)
+	if err := c.WriteMessage(&irc.Message{
+		Command: "BOUNCERSERV",
+		Params:  []string{quoteWords(words)},
+	}); err != nil {
+		return fmt.Errorf("write: %v", err)
+	}
+	for {
+		m, err := c.ReadMessage()
+		if err != nil {
+			return fmt.Errorf("read: %v", err)
+		}
+		switch m.Command {
+		case "PRIVMSG":
+			fmt.Println(m.Trailing())
+		case "BOUNCERSERV":
+			if m.Param(0) == "OK" {
+				return nil
+			}
+			return fmt.Errorf(m.Trailing())
+		default:
+			return fmt.Errorf(m.Trailing())
+		}
+	}
+}
+
+func main() {
+	var configPath string
+	flag.StringVar(&configPath, "config", config.DefaultPath, "path to configuration file")
+	flag.Parse()
+
+	var cfg *config.Server
+	if configPath != "" {
+		var err error
+		cfg, err = config.Load(configPath)
+		if err != nil {
+			log.Fatalf("failed to load config file: %v", err)
+		}
+	} else {
+		cfg = config.Defaults()
+	}
+
+	ctx := context.Background()
+	if err := run(ctx, cfg, flag.Args()); err != nil {
+		log.Fatalln(err)
+	}
+}
+
+func quoteWords(words []string) string {
+	var s strings.Builder
+	for _, word := range words {
+		if s.Len() > 0 {
+			s.WriteRune(' ')
+		}
+		s.WriteString(strconv.Quote(word))
+	}
+	return s.String()
+}