Pull request 2100: v0.107.42-rc

Squashed commit of the following:

commit 284190f748345c7556e60b67f051ec5f6f080948
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Wed Dec 6 19:36:00 2023 +0300

    all: sync with master; upd chlog

internal/next/cmd/cmd.go

@@ -0,0 +1,95 @@
+// Package cmd is the AdGuard Home entry point.  It assembles the configuration
+// file manager, sets up signal processing logic, and so on.
+//
+// TODO(a.garipov): Move to the upper-level internal/.
+package cmd
+
+import (
+	"context"
+	"io/fs"
+	"os"
+	"time"
+
+	"github.com/AdguardTeam/AdGuardHome/internal/next/configmgr"
+	"github.com/AdguardTeam/AdGuardHome/internal/version"
+	"github.com/AdguardTeam/golibs/log"
+)
+
+// Main is the entry point of AdGuard Home.
+func Main(embeddedFrontend fs.FS) {
+	start := time.Now()
+
+	cmdName := os.Args[0]
+	opts, err := parseOptions(cmdName, os.Args[1:])
+	exitCode, needExit := processOptions(opts, cmdName, err)
+	if needExit {
+		os.Exit(exitCode)
+	}
+
+	err = setLog(opts)
+	check(err)
+
+	log.Info("starting adguard home, version %s, pid %d", version.Version(), os.Getpid())
+
+	if opts.workDir != "" {
+		log.Info("changing working directory to %q", opts.workDir)
+		err = os.Chdir(opts.workDir)
+		check(err)
+	}
+
+	frontend, err := frontendFromOpts(opts, embeddedFrontend)
+	check(err)
+
+	confMgrConf := &configmgr.Config{
+		Frontend: frontend,
+		WebAddr:  opts.webAddr,
+		Start:    start,
+		FileName: opts.confFile,
+	}
+
+	confMgr, err := newConfigMgr(confMgrConf)
+	check(err)
+
+	web := confMgr.Web()
+	err = web.Start()
+	check(err)
+
+	dns := confMgr.DNS()
+	err = dns.Start()
+	check(err)
+
+	sigHdlr := newSignalHandler(
+		confMgrConf,
+		opts.pidFile,
+		web,
+		dns,
+	)
+
+	sigHdlr.handle()
+}
+
+// defaultTimeout is the timeout used for some operations where another timeout
+// hasn't been defined yet.
+const defaultTimeout = 5 * time.Second
+
+// ctxWithDefaultTimeout is a helper function that returns a context with
+// timeout set to defaultTimeout.
+func ctxWithDefaultTimeout() (ctx context.Context, cancel context.CancelFunc) {
+	return context.WithTimeout(context.Background(), defaultTimeout)
+}
+
+// newConfigMgr returns a new configuration manager using defaultTimeout as the
+// context timeout.
+func newConfigMgr(c *configmgr.Config) (m *configmgr.Manager, err error) {
+	ctx, cancel := ctxWithDefaultTimeout()
+	defer cancel()
+
+	return configmgr.New(ctx, c)
+}
+
+// check is a simple error-checking helper.  It must only be used within Main.
+func check(err error) {
+	if err != nil {
+		panic(err)
+	}
+}