```

feat(vms): 添加日志装饰器并优化chroot执行流程

- 新增LogDone函数用于统一处理开始/结束日志记录
- 将chroot函数重构为闭包形式，添加更完整的错误处理和日志记录
- 在VMS执行过程中统一使用LogDone进行状态跟踪
- 调整日志前缀从"boot"改为"vms"，将"exec"作为命令执行前缀
- 重构web运行逻辑，使用PreStart和OnStarted钩子替代旧的webStart函数
```

Author: cnk3x

cmd/xlp/main.go

@@ -46,7 +46,7 @@ func main() {
 	slog.InfoContext(ctx, fmt.Sprintf("force_download: %t", cfg.ForceDownload))
 
 	err := vms.Exec(
-		log.Prefix(ctx, "boot"),
+		log.Prefix(ctx, "vms"),
 
 		vms.Before(xunlei.Before(cfg)),
 		vms.Run(xunlei.Run(cfg)),

pkg/log/std.go

@@ -56,3 +56,17 @@ func (w *stdWriter) Write(buf []byte) (int, error) {
 	r := slog.NewRecord(time.Now(), level, string(buf), pc)
 	return origLen, w.h.Handle(w.ctx, r)
 }
+
+func LogDone(ctx context.Context, level slog.Level, module string, err *error, args ...any) (fDefer func()) {
+	if module != "" {
+		module += " "
+	}
+	slog.Log(ctx, level, module+"start", args...)
+	return func() {
+		if err != nil && *err != nil {
+			slog.LogAttrs(ctx, level, module+"begin", slog.String("err", (*err).Error()))
+		} else {
+			slog.Log(ctx, level, module+"done")
+		}
+	}
+}

pkg/vms/sys/chroot.go

@@ -13,45 +13,46 @@ import (
 
 // chroot & run
 func Chroot(ctx context.Context, newRoot string, run func(ctx context.Context) error, debug ...bool) (err error) {
-	var wd string
-	if wd, err = os.Getwd(); err != nil {
+	err = func() (err error) {
+		var wd string
+		if wd, err = os.Getwd(); err != nil {
+			return
+		}
+		defer log.LogDone(ctx, slog.LevelDebug, "chroot ", &err, "root", newRoot, "wd", wd)
+
+		if err = syscall.Chdir(newRoot); err != nil {
+			return
+		}
+		defer syscall.Chdir(wd)
+
+		var rfd int
+		if rfd, err = syscall.Open("/", syscall.O_RDONLY, 0); err != nil {
+			return
+		}
+		defer syscall.Close(rfd)
+
+		if err = syscall.Chroot("."); err != nil {
+			return
+		}
+
+		defer func() {
+			err = utils.SeqExec(
+				func() error { return syscall.Fchdir(rfd) },
+				func() error { return syscall.Chroot(".") },
+				func() error { return syscall.Chdir(wd) },
+			)
+			slog.Log(ctx, log.WarnDebug(err), "back to old root", "fd", rfd, "wd", wd, "err", err)
+		}()
+
+		if err = syscall.Chdir("/"); err != nil {
+			return
+		}
+
+		slog.DebugContext(ctx, "run start")
+		err = run(ctx)
 		return
-	}
-	slog.DebugContext(ctx, "chroot", "root", newRoot, "wd", wd)
-
-	if err = syscall.Chdir(newRoot); err != nil {
-		return
-	}
-	defer syscall.Chdir(wd)
-
-	var rfd int
-	if rfd, err = syscall.Open("/", syscall.O_RDONLY, 0); err != nil {
-		return
-	}
-	defer syscall.Close(rfd)
-
-	if err = syscall.Chroot("."); err != nil {
-		return
-	}
-
-	defer func() {
-		err = utils.SeqExec(
-			func() error { return syscall.Fchdir(rfd) },
-			func() error { return syscall.Chroot(".") },
-			func() error { return syscall.Chdir(wd) },
-		)
-		slog.Log(ctx, log.WarnDebug(err), "back to old root", "fd", rfd, "wd", wd, "err", err)
 	}()
 
-	if err = syscall.Chdir("/"); err != nil {
-		return
-	}
-
-	slog.DebugContext(ctx, "run start")
-	if err = run(ctx); err != nil {
-		slog.DebugContext(ctx, "run done", "err", err.Error())
-	}
-
 	if cmp.Or(debug...) {
 		<-ctx.Done()
 	}

pkg/vms/vms.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"log/slog"
 
+	"github.com/cnk3x/xunlei/pkg/log"
 	"github.com/cnk3x/xunlei/pkg/utils"
 	"github.com/cnk3x/xunlei/pkg/vms/sys"
 )
@@ -32,8 +33,7 @@ type options struct {
 //   - chroot + seteuid 实现权限最小化（临时降权）
 //   - 执行顺序 root 启动 → 准备 chroot 监狱 → chroot 切换 → setegid/seteuid 降权 → 执行核心任务 → 恢复 root 权限
 func Exec(ctx context.Context, execOpts ...Option) (err error) {
-	slog.InfoContext(ctx, "vms start")
-	defer slog.InfoContext(ctx, "vms done")
+	defer log.LogDone(ctx, slog.LevelInfo, "vms", &err)
 
 	var opts options
 	for _, option := range execOpts {
@@ -58,15 +58,15 @@ func Exec(ctx context.Context, execOpts ...Option) (err error) {
 		defer beforeUndo()
 	}
 
-	run := func(ctx context.Context) error {
-		slog.InfoContext(ctx, "runner start")
-		defer slog.InfoContext(ctx, "runner done")
-		return sys.RunAs(ctx, opts.uid, opts.gid, func() error {
+	run := func(ctx context.Context) (err error) {
+		defer log.LogDone(ctx, slog.LevelInfo, "runner", &err)
+		err = sys.RunAs(ctx, opts.uid, opts.gid, func() error {
 			if opts.run == nil {
 				return nil
 			}
 			return opts.run(ctx)
 		})
+		return
 	}
 
 	if opts.root == "" || opts.root == "/" {

xlp.go

@@ -96,8 +96,7 @@ func Before(cfg Config) func(ctx context.Context) (func(), error) {
 
 func Run(cfg Config) func(ctx context.Context) error {
 	return func(ctx context.Context) (err error) {
-		slog.InfoContext(ctx, "app start")
-		defer slog.InfoContext(ctx, "app done")
+		defer log.LogDone(ctx, slog.LevelInfo, "xlp", &err)
 
 		ctx, cancel := context.WithCancelCause(ctx)
 		defer cancel(fmt.Errorf("done"))
@@ -114,27 +113,8 @@ func Run(cfg Config) func(ctx context.Context) error {
 
 		envs := mockEnv(dirData[0], strings.Join(dirDownload, ":"))
 
-		webStart := func(c *cmdx.Cmd) error {
-			if cfg.Debug {
-				cmdx.Exec(ctx,
-					FILE_PAN_XUNLEI_CLI,
-					cmdx.Dir(DIR_SYNOPKG_WORK),
-					cmdx.Env(append(os.Environ(), "LD_TRACE_LOADED_OBJECTS=1")),
-					cmdx.LineErr(logPan(ctx, "[test] ")), cmdx.LineOut(logPan(ctx, "[test]* ")),
-				)
-			}
-			utils.BackExec(func() {
-				if err := webRun(ctx, envs, cfg); err != nil {
-					cancel(err)
-				} else {
-					cancel(fmt.Errorf("web done"))
-				}
-			})
-			return nil
-		}
-
 		return cmdx.Exec(
-			log.Prefix(ctx, "vms"),
+			log.Prefix(ctx, "exec"),
 			FILE_PAN_XUNLEI_CLI,
 			cmdx.Flags(
 				"-launcher_listen", "unix://"+SOCK_LAUNCHER_LISTEN,
@@ -146,14 +126,32 @@ func Run(cfg Config) func(ctx context.Context) error {
 			cmdx.Env(envs),
 			cmdx.LineErr(logPan(ctx, "[stderr] ")),
 			cmdx.LineOut(logPan(ctx, "[stdout] ")),
-			cmdx.OnStarted(webStart),
+			cmdx.PreStart(func(c *cmdx.Cmd) error {
+				return cmdx.Exec(ctx,
+					FILE_PAN_XUNLEI_CLI,
+					cmdx.Dir(DIR_SYNOPKG_WORK),
+					cmdx.Env(append(os.Environ(), "LD_TRACE_LOADED_OBJECTS=1")),
+					cmdx.LineErr(logPan(ctx, "[test] ")), cmdx.LineOut(logPan(ctx, "[test]* ")),
+				)
+			}),
+			cmdx.OnStarted(func(c *cmdx.Cmd) error {
+				done := utils.BackExec(func() {
+					if err := webRun(ctx, envs, cfg); err != nil {
+						cancel(err)
+					}
+				})
+				utils.After(done, func() { cancel(fmt.Errorf("web done")) })
+				return nil
+			}),
 			cmdx.OnExit(func(c *cmdx.Cmd) error { return cleanExit(DIR_VAR) }),
 		)
 	}
 }
 
 func webRun(ctx context.Context, env []string, cfg Config) (err error) {
 	ctx = log.Prefix(ctx, "web")
+	defer log.LogDone(ctx, slog.LevelInfo, "web", &err)
+
 	mux := web.NewMux()
 	mux.Recoverer()