Makefile: fix lint rules

use errors.Join

Makefile

@@ -1,4 +1,4 @@
-SCRIPTS = $(shell awk '/#!\/bin\/(ba)?sh/&&FNR==1{print FILENAME}' $(shell git ls-files))
+SCRIPTS = $(shell awk '/#!\/usr\/bin\/env (ba)?sh/&&FNR==1{print FILENAME}' $(shell git ls-files))
 GODEPS = $(shell git ls-files '*.go' go.mod go.sum)
 
 VSN ?= $(shell git describe --dirty)
@@ -14,7 +14,7 @@ test: coverage.out
 .PHONY: lint
 lint:
 	go vet ./...
-	$(shell go env GOPATH)/bin/staticcheck -f stylish ./...
+	staticcheck -f stylish ./...
 	shellcheck $(SCRIPTS)
 
 .INTERMEDIATE: coverage.out

README.md

@@ -5,6 +5,15 @@ Undocker
 
 Converts a Docker image (a bunch of layers) to a flattened "rootfs" tarball.
 
+Project Status
+--------------
+
+The project was announced to be deprecated in the beginning of 2024, but the
+maintainer has an interest in Docker ecosystem again, thus will maintain it
+somewhat starting at mid-2024.
+
+The author has some significant changes in mind, but the timeline is unknown.
+
 Why?
 ----
 
@@ -79,13 +88,6 @@ Similar Projects
 
 * [rootfs_builder](https://github.com/ForAllSecure/rootfs_builder)
 
-Changelog
----------
-
-**v1.0**
-
-* initial release: `rootfs.Flatten` and a simple command-line application.
-
 Contributions
 -------------
 

go.mod

@@ -1,3 +1,3 @@
 module git.jakstys.lt/motiejus/undocker
 
-go 1.16
+go 1.20

main.go

@@ -2,6 +2,7 @@
 package main
 
 import (
+	"errors"
 	"fmt"
 	"io"
 	"os"
@@ -42,7 +43,7 @@ func main() {
 
 	c := &command{flattener: rootfs.Flatten, Stdout: os.Stdout}
 	if err := c.execute(os.Args[1], os.Args[2]); err != nil {
-		fmt.Printf("Error: %v\n", err)
+		fmt.Fprintf(os.Stderr, "Error: %v\n", err)
 		os.Exit(1)
 	}
 	os.Exit(0)
@@ -59,10 +60,7 @@ func (c *command) execute(infile string, outfile string) (_err error) {
 		return err
 	}
 	defer func() {
-		err := rd.Close()
-		if _err == nil {
-			_err = err
-		}
+		_err = errors.Join(_err, rd.Close())
 	}()
 
 	var out io.Writer
@@ -74,11 +72,10 @@ func (c *command) execute(infile string, outfile string) (_err error) {
 			return fmt.Errorf("create: %w", err)
 		}
 		defer func() {
-			err := outf.Close()
 			if _err != nil {
-				os.Remove(outfile)
+				_err = errors.Join(_err, os.Remove(outfile))
 			} else {
-				_err = err
+				_err = errors.Join(_err, outf.Close())
 			}
 		}()
 		out = outf

release

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 set -euo pipefail
 
 _err(){ >&2 echo "ERROR: $*"; exit 1; }
@@ -22,4 +22,4 @@ last_tag=$(git tag | tail -1)
     echo
     echo Changelog since "$last_tag":
     git log --pretty=format:"- [%an] %s" "$last_tag"..HEAD
-} | git tag -u motiejus@jakstys.lt -F - "$1"
+} | git tag -F - "$1"

rootfs/rootfs.go

@@ -144,11 +144,7 @@ func Flatten(rd io.ReadSeeker, w io.Writer) (_err error) {
 
 	tw := tar.NewWriter(w)
 	defer func() {
-		// Avoiding use of multierr: if error is present, return
-		// that. Otherwise return whatever `Close` returns.
-		if err := tw.Close(); err != nil && _err == nil {
-			_err = err
-		}
+		_err = errors.Join(_err, tw.Close())
 	}()
 	// iterate through all layers, all files, and write files.
 	for i, no := range layers {