refactor: drop logrus and other direct dependencies (#1319)

After https://gitea.com/gitea/runner/pulls/1304, logrus stayed only to forward logs from docker/cli and moby/go-archive. The runner used a small part of those: volume parsing, the build context tar, the `ssh://` connection and registry credentials. Own code that matches them replaces them, so logrus leaves the module graph. docker/cli stays for its logrus-free `opts` and `connhelper/ssh` packages.

Other dependencies that the standard library or existing ones cover go too: mergo, httprouter (replaced by `http.ServeMux`), retry-go, go-isatty, go-selinux, container-device-interface, gotest.tools and go-cmp (replaced by testify). The binary shrinks by 5%.

Behaviour differences:

1. An unreadable file in a build context is skipped with a warning, where go-archive left a truncated tar.
2. Build contexts no longer carry `security.capability` xattrs.
3. The cache and artifact servers answer HEAD on GET routes, and no longer redirect trailing slashes or answer OPTIONS.

*Written by Claude.*

---------

Co-authored-by: bircni <[email protected]>
Reviewed-on: https://gitea.com/gitea/runner/pulls/1319
Reviewed-by: bircni <[email protected]>
Reviewed-by: Lunny Xiao <[email protected]>
Co-authored-by: silverwind <[email protected]>

act/container/docker_auth.go

@@ -7,20 +7,33 @@
 package container
 
 import (
+	"bytes"
 	"context"
+	"encoding/base64"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"io/fs"
+	"maps"
+	"net"
+	"net/url"
+	"os"
+	"os/exec"
+	"os/user"
+	"path/filepath"
+	"runtime"
+	"strings"
 
 	"gitea.com/gitea/runner/act/common"
 
 	"github.com/distribution/reference"
-	"github.com/docker/cli/cli/config"
 	"github.com/moby/moby/api/types/registry"
 )
 
 func LoadDockerAuthConfig(ctx context.Context, image string) (registry.AuthConfig, error) {
 	logger := common.Logger(ctx)
-	// config.LoadDefaultConfigFile panics on nil io.Writer when the config
-	// file is malformed; use config.Load to route errors through the logger.
-	cfg, err := config.Load(config.Dir())
+	cfg, err := loadDockerConfig(ctx)
 	if err != nil {
 		logger.Warnf("Could not load docker config: %v", err)
 		return registry.AuthConfig{}, err
@@ -34,32 +47,27 @@ func LoadDockerAuthConfig(ctx context.Context, image string) (registry.AuthConfi
 		}
 	}
 
-	authConfig, err := cfg.GetAuthConfig(registryKey)
+	authConfig, err := cfg.authConfig(ctx, registryKey)
 	if err != nil {
 		logger.Warnf("Could not get auth config from docker config: %v", err)
 		return registry.AuthConfig{}, err
 	}
 
-	return registry.AuthConfig(authConfig), nil
+	return authConfig, nil
 }
 
 func LoadDockerAuthConfigs(ctx context.Context) map[string]registry.AuthConfig {
 	logger := common.Logger(ctx)
-	cfg, err := config.Load(config.Dir())
+	cfg, err := loadDockerConfig(ctx)
 	if err != nil {
 		logger.Warnf("Could not load docker config: %v", err)
 		return nil
 	}
-	creds, err := cfg.GetAllCredentials()
+	authConfigs, err := cfg.allAuthConfigs(ctx)
 	if err != nil {
 		logger.Warnf("Could not get docker auth configs: %v", err)
 		return nil
 	}
-	authConfigs := make(map[string]registry.AuthConfig, len(creds))
-	for k, v := range creds {
-		authConfigs[k] = registry.AuthConfig(v)
-	}
-
 	return authConfigs
 }
 
@@ -69,3 +77,226 @@ func registryAuthConfigKey(domainName string) string {
 	}
 	return domainName
 }
+
+type dockerConfig struct {
+	Auths       map[string]registry.AuthConfig `json:"auths"`
+	CredsStore  string                         `json:"credsStore"`
+	CredHelpers map[string]string              `json:"credHelpers"`
+	env         map[string]registry.AuthConfig // from DOCKER_AUTH_CONFIG, nil when unset or unusable
+}
+
+func loadDockerConfig(ctx context.Context) (*dockerConfig, error) {
+	dir := os.Getenv("DOCKER_CONFIG")
+	if dir == "" {
+		home, _ := os.UserHomeDir()
+		if home == "" && runtime.GOOS != "windows" {
+			if current, err := user.Current(); err == nil {
+				home = current.HomeDir
+			}
+		}
+		dir = filepath.Join(home, ".docker")
+	}
+	cfg := &dockerConfig{}
+	filename := filepath.Join(dir, "config.json")
+	file, err := os.Open(filename)
+	if err != nil && !errors.Is(err, fs.ErrNotExist) {
+		return nil, fmt.Errorf("loading config file: %w", err)
+	}
+	if err == nil {
+		defer file.Close()
+		if err := json.NewDecoder(file).Decode(cfg); err != nil && !errors.Is(err, io.EOF) {
+			return nil, fmt.Errorf("parsing config file (%s): %w", filename, err)
+		}
+	}
+	for address, auth := range cfg.Auths {
+		if auth.Auth != "" {
+			if auth.Username, auth.Password, err = decodeAuth(auth.Auth); err != nil {
+				return nil, fmt.Errorf("parsing config file (%s): %w", filename, err)
+			}
+		}
+		auth.Auth, auth.ServerAddress = "", address
+		cfg.Auths[address] = auth
+	}
+	if value := os.Getenv("DOCKER_AUTH_CONFIG"); value != "" {
+		if cfg.env, err = parseDockerAuthConfigEnv(value); err != nil {
+			common.Logger(ctx).Warnf("Failed to create credential store from DOCKER_AUTH_CONFIG: %v", err)
+		}
+	}
+	return cfg, nil
+}
+
+func decodeAuth(auth string) (string, string, error) {
+	decoded, err := base64.StdEncoding.DecodeString(auth)
+	if err != nil {
+		return "", "", err
+	}
+	username, password, ok := strings.Cut(string(decoded), ":")
+	if !ok || username == "" {
+		return "", "", errors.New("invalid auth configuration file")
+	}
+	return username, strings.Trim(password, "\x00"), nil
+}
+
+func parseDockerAuthConfigEnv(value string) (map[string]registry.AuthConfig, error) {
+	var env struct {
+		Auths map[string]struct {
+			Auth string `json:"auth"`
+		} `json:"auths"`
+	}
+	decoder := json.NewDecoder(strings.NewReader(value))
+	decoder.DisallowUnknownFields()
+	if err := decoder.Decode(&env); err != nil && !errors.Is(err, io.EOF) {
+		return nil, err
+	}
+	if decoder.More() {
+		return nil, errors.New("DOCKER_AUTH_CONFIG does not support more than one JSON object")
+	}
+	auths := make(map[string]registry.AuthConfig, len(env.Auths))
+	for address, entry := range env.Auths {
+		if entry.Auth == "" {
+			return nil, fmt.Errorf("DOCKER_AUTH_CONFIG environment variable is missing key `auth` for %s", address)
+		}
+		username, password, err := decodeAuth(entry.Auth)
+		if err != nil {
+			return nil, err
+		}
+		auths[address] = registry.AuthConfig{Username: username, Password: password, ServerAddress: address}
+	}
+	return auths, nil
+}
+
+func (c *dockerConfig) authConfig(ctx context.Context, key string) (registry.AuthConfig, error) {
+	if auth, ok := c.env[key]; ok {
+		return auth, nil
+	}
+	helper := c.CredsStore
+	if named, ok := c.CredHelpers[key]; ok {
+		helper = named
+	}
+	if helper == "" {
+		return c.fileAuth(key), nil
+	}
+	auth := c.fileAuth(key)
+	stored, err := helperCredentials(ctx, helper, key)
+	if err != nil {
+		return auth, err
+	}
+	auth.Username, auth.Password, auth.IdentityToken, auth.ServerAddress = stored.Username, stored.Password, stored.IdentityToken, stored.ServerAddress
+	return auth, nil
+}
+
+func (c *dockerConfig) fileAuth(key string) registry.AuthConfig {
+	if auth, ok := c.Auths[key]; ok {
+		return auth
+	}
+	for address, auth := range c.Auths {
+		if registryHostname(address) == key {
+			return auth
+		}
+	}
+	return registry.AuthConfig{}
+}
+
+func (c *dockerConfig) allAuthConfigs(ctx context.Context) (map[string]registry.AuthConfig, error) {
+	var auths map[string]registry.AuthConfig
+	if c.CredsStore == "" {
+		auths = maps.Clone(c.Auths)
+	} else {
+		var err error
+		if auths, err = c.helperAuthConfigs(ctx); err != nil {
+			if c.env == nil {
+				return nil, err
+			}
+			common.Logger(ctx).Warnf("Could not list the credentials of docker-credential-%s: %v", c.CredsStore, err)
+		}
+	}
+	if auths == nil {
+		auths = map[string]registry.AuthConfig{}
+	}
+	maps.Copy(auths, c.env)
+	if c.CredsStore == "" {
+		c.Auths = maps.Clone(auths) // docker's file store holds the DOCKER_AUTH_CONFIG entries after listing, and credHelpers set to "" read it
+	}
+	for address := range c.CredHelpers {
+		auth, err := c.authConfig(ctx, registryAuthConfigKey(address))
+		if err != nil {
+			common.Logger(ctx).Warnf("Failed to get credentials for registry: %s: %v", address, err)
+			continue
+		}
+		auths[address] = auth
+	}
+	return auths, nil
+}
+
+func (c *dockerConfig) helperAuthConfigs(ctx context.Context) (map[string]registry.AuthConfig, error) {
+	out, err := runCredentialHelper(ctx, c.CredsStore, "list", "unused")
+	if err != nil {
+		return nil, fmt.Errorf("error listing credentials - err: %w, out: `%s`", err, strings.TrimSpace(string(out)))
+	}
+	var addresses map[string]string
+	if err := json.NewDecoder(bytes.NewReader(out)).Decode(&addresses); err != nil {
+		return nil, err
+	}
+	auths := make(map[string]registry.AuthConfig, len(addresses))
+	for address := range addresses {
+		stored, err := helperCredentials(ctx, c.CredsStore, address)
+		if err != nil {
+			return nil, err
+		}
+		auth := c.Auths[address]
+		auth.Username, auth.Password, auth.IdentityToken = stored.Username, stored.Password, stored.IdentityToken
+		if auth.ServerAddress == "" {
+			auth.ServerAddress = stored.ServerAddress
+		}
+		auths[address] = auth
+	}
+	return auths, nil
+}
+
+func helperCredentials(ctx context.Context, helper, address string) (registry.AuthConfig, error) {
+	out, err := runCredentialHelper(ctx, helper, "get", address)
+	if err != nil {
+		if strings.TrimSpace(string(out)) == "credentials not found in native keychain" {
+			return registry.AuthConfig{}, nil
+		}
+		return registry.AuthConfig{}, fmt.Errorf("error getting credentials - err: %w, out: `%s`", err, strings.TrimSpace(string(out)))
+	}
+	var stored struct{ Username, Secret string }
+	if err := json.NewDecoder(bytes.NewReader(out)).Decode(&stored); err != nil {
+		return registry.AuthConfig{}, err
+	}
+	if stored.Username == "<token>" {
+		return registry.AuthConfig{IdentityToken: stored.Secret, ServerAddress: address}, nil
+	}
+	return registry.AuthConfig{Username: stored.Username, Password: stored.Secret, ServerAddress: address}, nil
+}
+
+func runCredentialHelper(ctx context.Context, helper, action, input string) ([]byte, error) {
+	cmd := exec.CommandContext(ctx, "docker-credential-"+helper, action)
+	cmd.Stdin = strings.NewReader(input)
+	cmd.Stderr = os.Stderr
+	return cmd.Output()
+}
+
+func registryHostname(address string) string {
+	if _, rest, ok := strings.Cut(address, "://"); ok {
+		if u, err := url.Parse(address); err == nil && u.Hostname() != "" {
+			if u.Port() == "" {
+				return u.Hostname()
+			}
+			return net.JoinHostPort(u.Hostname(), u.Port())
+		}
+		if host, _, _ := strings.Cut(rest, "/"); host != "" {
+			if colon := strings.LastIndex(host, ":"); strings.Count(host, ":") > 1 && !strings.HasPrefix(host, "[") && isDigits(host[colon+1:]) {
+				return net.JoinHostPort(host[:colon], host[colon+1:])
+			}
+			return host
+		}
+	}
+	host, _, _ := strings.Cut(address, "/")
+	return host
+}
+
+func isDigits(s string) bool {
+	return s != "" && strings.Trim(s, "0123456789") == ""
+}

act/container/docker_auth_test.go

@@ -0,0 +1,46 @@
+// Copyright 2026 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+//go:build !windows && !(WITHOUT_DOCKER || !(linux || darwin || netbsd))
+
+package container
+
+import (
+	"encoding/base64"
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/moby/moby/api/types/registry"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestLoadDockerAuthConfigFromFileHelpersAndEnv(t *testing.T) {
+	dir := t.TempDir()
+	require.NoError(t, os.WriteFile(filepath.Join(dir, "docker-credential-fake"), []byte("#!/bin/sh\nread -r server\n[ \"$1\" = get ] && [ \"$server\" = helper.example.com ] && exec echo '{\"Username\":\"helped\",\"Secret\":\"pw\"}'\necho 'credentials not found in native keychain'\nexit 1\n"), 0o755))
+	t.Setenv("PATH", dir+string(os.PathListSeparator)+os.Getenv("PATH"))
+	auth := func(credentials string) string { return base64.StdEncoding.EncodeToString([]byte(credentials)) }
+	require.NoError(t, os.WriteFile(filepath.Join(dir, "config.json"), []byte(`{"auths": {"https://legacy.example.com/v1/": {"auth": "`+auth("legacy:pw")+`"}}, "credHelpers": {"helper.example.com": "fake", "gone.example.com": "fake", "env-legacy.example.com": ""}}`), 0o600))
+	t.Setenv("DOCKER_CONFIG", dir)
+	t.Setenv("DOCKER_AUTH_CONFIG", `{"auths": {"env.example.com": {"auth": "`+auth("env:pw")+`"}, "https://env-legacy.example.com/v1/": {"auth": "`+auth("env:pw")+`"}}}`)
+
+	for image, want := range map[string]registry.AuthConfig{
+		"legacy.example.com/app": {Username: "legacy", Password: "pw", ServerAddress: "https://legacy.example.com/v1/"},
+		"helper.example.com/app": {Username: "helped", Password: "pw", ServerAddress: "helper.example.com"},
+		"env.example.com/app":    {Username: "env", Password: "pw", ServerAddress: "env.example.com"},
+		"gone.example.com/app":   {},
+	} {
+		got, err := LoadDockerAuthConfig(t.Context(), image)
+		require.NoError(t, err)
+		assert.Equal(t, want, got, image)
+	}
+	assert.Equal(t, map[string]registry.AuthConfig{
+		"https://legacy.example.com/v1/":     {Username: "legacy", Password: "pw", ServerAddress: "https://legacy.example.com/v1/"},
+		"helper.example.com":                 {Username: "helped", Password: "pw", ServerAddress: "helper.example.com"},
+		"gone.example.com":                   {},
+		"env.example.com":                    {Username: "env", Password: "pw", ServerAddress: "env.example.com"},
+		"https://env-legacy.example.com/v1/": {Username: "env", Password: "pw", ServerAddress: "https://env-legacy.example.com/v1/"},
+		"env-legacy.example.com":             {Username: "env", Password: "pw", ServerAddress: "https://env-legacy.example.com/v1/"},
+	}, LoadDockerAuthConfigs(t.Context()))
+}

act/container/docker_build.go

@@ -7,15 +7,18 @@
 package container
 
 import (
+	"archive/tar"
 	"context"
 	"io"
+	"io/fs"
 	"os"
 	"path/filepath"
+	"runtime"
+	"strings"
+	"time"
 
 	"gitea.com/gitea/runner/act/common"
 
-	"github.com/moby/go-archive"
-	"github.com/moby/go-archive/compression"
 	"github.com/moby/moby/client"
 	"github.com/moby/patternmatcher"
 	"github.com/moby/patternmatcher/ignorefile"
@@ -115,14 +118,140 @@ func createBuildContext(ctx context.Context, contextDir, relDockerfile string) (
 		includes = append(includes, ".dockerignore", relDockerfile)
 	}
 
-	buildCtx, err := archive.TarWithOptions(contextDir, &archive.TarOptions{
-		Compression:     compression.None,
-		ExcludePatterns: excludes,
-		IncludeFiles:    includes,
-	})
+	pm, err := patternmatcher.New(excludes)
 	if err != nil {
 		return nil, err
 	}
-
-	return buildCtx, nil
+	reader, writer := io.Pipe()
+	go func() { writer.CloseWithError(writeBuildContext(ctx, writer, contextDir, includes, pm)) }()
+	return reader, nil
 }
+
+func writeBuildContext(ctx context.Context, w io.Writer, contextDir string, includes []string, pm *patternmatcher.PatternMatcher) error {
+	tw := tar.NewWriter(w)
+	seen := map[string]bool{}
+	hardlinks := map[uint64]string{}
+	buffer := make([]byte, 32*1024)
+	for _, include := range includes {
+		include = filepath.FromSlash(include)
+		var parents []parentMatch
+		root := strings.TrimSuffix(contextDir, string(filepath.Separator)) + string(filepath.Separator) + include // unlike filepath.Join, follows a symlinked context dir as docker build does
+		err := filepath.WalkDir(root, func(file string, entry fs.DirEntry, err error) error {
+			if err != nil {
+				return leaveOut(ctx, file, err)
+			}
+			rel, err := filepath.Rel(contextDir, file)
+			if err != nil || rel == "." {
+				return nil
+			}
+			if rel != include {
+				for len(parents) > 0 && !strings.HasPrefix(rel, parents[len(parents)-1].dir+string(filepath.Separator)) {
+					parents = parents[:len(parents)-1]
+				}
+				var parentInfo patternmatcher.MatchInfo
+				if len(parents) > 0 {
+					parentInfo = parents[len(parents)-1].info
+				}
+				skip, info, err := pm.MatchesUsingParentResults(rel, parentInfo)
+				if err != nil {
+					return err
+				}
+				if entry.IsDir() {
+					parents = append(parents, parentMatch{rel, info})
+				}
+				if skip {
+					if entry.IsDir() && !hasExceptionWithin(pm, rel) {
+						return filepath.SkipDir
+					}
+					return nil
+				}
+			}
+			if seen[rel] {
+				return nil
+			}
+			seen[rel] = true
+			return addBuildContextEntry(ctx, tw, file, rel, entry, hardlinks, buffer)
+		})
+		if err != nil {
+			return err
+		}
+	}
+	return tw.Close()
+}
+
+type parentMatch struct {
+	dir  string
+	info patternmatcher.MatchInfo
+}
+
+func hasExceptionWithin(pm *patternmatcher.PatternMatcher, dir string) bool {
+	dirPrefix := dir + string(filepath.Separator)
+	for _, pattern := range pm.Patterns() {
+		if pattern.Exclusion() && strings.HasPrefix(pattern.String()+string(filepath.Separator), dirPrefix) {
+			return true
+		}
+	}
+	return false
+}
+
+func leaveOut(ctx context.Context, file string, err error) error {
+	common.Logger(ctx).Warnf("Leaving %s out of the build context: %v", file, err)
+	return nil
+}
+
+func addBuildContextEntry(ctx context.Context, tw *tar.Writer, file, rel string, entry fs.DirEntry, hardlinks map[uint64]string, buffer []byte) error {
+	info, err := entry.Info()
+	if err != nil {
+		return leaveOut(ctx, file, err)
+	}
+	if info.Mode()&fs.ModeSocket != 0 {
+		return nil // tar has no socket type
+	}
+	var link string
+	if info.Mode()&fs.ModeSymlink != 0 {
+		if link, err = os.Readlink(file); err != nil {
+			return leaveOut(ctx, file, err)
+		}
+	}
+	header, err := tar.FileInfoHeader(noNameLookups{info}, link)
+	if err != nil {
+		return err
+	}
+	header.Name = filepath.ToSlash(rel)
+	inode, linked := hardlinkInode(info)
+	if target, ok := hardlinks[inode]; linked && ok {
+		header.Typeflag, header.Linkname, header.Size = tar.TypeLink, target, 0
+	}
+	var content *os.File
+	if header.Typeflag == tar.TypeReg && header.Size > 0 {
+		if content, err = os.Open(file); err != nil {
+			return leaveOut(ctx, file, err)
+		}
+		defer content.Close()
+	}
+	if linked && header.Typeflag != tar.TypeLink {
+		hardlinks[inode] = header.Name
+	}
+	if info.IsDir() {
+		header.Name += "/"
+	}
+	header.Format = tar.FormatPAX
+	header.ModTime = header.ModTime.Truncate(time.Second)
+	header.AccessTime, header.ChangeTime = time.Time{}, time.Time{}
+	if runtime.GOOS == "windows" {
+		header.Mode = header.Mode&0o755 | 0o111 // Windows has no exec bit, so mark everything executable like docker build
+	}
+	if err := tw.WriteHeader(header); err != nil {
+		return err
+	}
+	if content != nil {
+		_, err = io.CopyBuffer(tw, struct{ io.Reader }{content}, buffer) // hides os.File's WriteTo, which would allocate a buffer per file
+	}
+	return err
+}
+
+type noNameLookups struct{ fs.FileInfo } // leaves Uname and Gname empty like docker build, so packing never waits on NSS
+
+func (noNameLookups) Uname() (string, error) { return "", nil }
+
+func (noNameLookups) Gname() (string, error) { return "", nil }

act/container/docker_build_test.go

@@ -0,0 +1,49 @@
+// Copyright 2026 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+//go:build !(WITHOUT_DOCKER || !(linux || darwin || windows || netbsd))
+
+package container
+
+import (
+	"archive/tar"
+	"io"
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestCreateBuildContextFollowsDockerignoreAndSymlinkedRootButKeepsDockerfile(t *testing.T) {
+	dir := t.TempDir()
+	for name, content := range map[string]string{
+		".dockerignore": "*.log\nbuild\n!build/keep.txt\nDockerfile", "Dockerfile": "FROM scratch", "a.txt": "a",
+		"a.log": "log", "build/drop.txt": "drop", "build/keep.txt": "keep",
+	} {
+		require.NoError(t, os.MkdirAll(filepath.Join(dir, filepath.Dir(name)), 0o755))
+		require.NoError(t, os.WriteFile(filepath.Join(dir, name), []byte(content), 0o644))
+	}
+	require.NoError(t, os.Mkdir(filepath.Join(dir, "empty"), 0o755))
+
+	contexts := []string{dir}
+	if link := filepath.Join(t.TempDir(), "link"); os.Symlink(dir, link) == nil {
+		contexts = append(contexts, link+string(filepath.Separator))
+	}
+
+	for _, contextDir := range contexts {
+		buildContext, err := createBuildContext(t.Context(), contextDir, "Dockerfile")
+		require.NoError(t, err)
+		var names []string
+		for reader := tar.NewReader(buildContext); ; {
+			header, err := reader.Next()
+			if err == io.EOF {
+				break
+			}
+			require.NoError(t, err)
+			names = append(names, header.Name)
+		}
+		require.NoError(t, buildContext.Close())
+		require.Equal(t, []string{".dockerignore", "a.txt", "build/keep.txt", "empty/", "Dockerfile"}, names, contextDir)
+	}
+}

act/container/docker_build_unix.go

@@ -0,0 +1,18 @@
+// Copyright 2026 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+//go:build !WITHOUT_DOCKER && (linux || darwin || netbsd)
+
+package container
+
+import (
+	"io/fs"
+	"syscall"
+)
+
+func hardlinkInode(info fs.FileInfo) (uint64, bool) {
+	if stat, ok := info.Sys().(*syscall.Stat_t); ok && !info.IsDir() && stat.Nlink > 1 {
+		return stat.Ino, true
+	}
+	return 0, false
+}

act/container/docker_build_unix_test.go

@@ -0,0 +1,35 @@
+// Copyright 2026 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+//go:build !WITHOUT_DOCKER && (linux || darwin || netbsd)
+
+package container
+
+import (
+	"archive/tar"
+	"os"
+	"path/filepath"
+	"syscall"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestCreateBuildContextKeepsHardlinkedSpecialFilesLinked(t *testing.T) {
+	dir := t.TempDir()
+	require.NoError(t, syscall.Mkfifo(filepath.Join(dir, "first"), 0o644))
+	require.NoError(t, os.Link(filepath.Join(dir, "first"), filepath.Join(dir, "second")))
+
+	buildContext, err := createBuildContext(t.Context(), dir, "Dockerfile")
+	require.NoError(t, err)
+	defer buildContext.Close()
+	reader := tar.NewReader(buildContext)
+	first, err := reader.Next()
+	require.NoError(t, err)
+	assert.Equal(t, byte(tar.TypeFifo), first.Typeflag)
+	second, err := reader.Next()
+	require.NoError(t, err)
+	assert.Equal(t, byte(tar.TypeLink), second.Typeflag)
+	assert.Equal(t, first.Name, second.Linkname)
+}

act/container/docker_build_windows.go

@@ -0,0 +1,10 @@
+// Copyright 2026 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+//go:build !WITHOUT_DOCKER
+
+package container
+
+import "io/fs"
+
+func hardlinkInode(_info fs.FileInfo) (uint64, bool) { return 0, false }

act/container/docker_cli.go

@@ -6,7 +6,8 @@
 
 // This file is exact copy of https://github.com/docker/cli/blob/4a63305d74332de5ceba7fcbccbc3cbb7412f5ba/cli/command/container/opts.go with:
 // * appended with license information
-// * regexp and loader.ParseVolume in place of the import-restricted internal/lazyregexp and internal/volumespec
+// * regexp and ParseVolume in place of the import-restricted internal/lazyregexp and internal/volumespec
+// * cdiDeviceName in place of the container-device-interface parser's IsQualifiedName
 // * jsontext in place of json.Compact for the seccomp profile
 // * invalidParameter from the package's errors.go, and convertPortSet/convertPortMap for the callers in docker_run.go
 //
@@ -33,14 +34,12 @@ import (
 	"time"
 
 	cerrdefs "github.com/containerd/errdefs"
-	"github.com/docker/cli/cli/compose/loader"
 	"github.com/docker/cli/opts"
 	"github.com/docker/go-connections/nat"
 	"github.com/moby/moby/api/types/container"
 	"github.com/moby/moby/api/types/mount"
 	"github.com/moby/moby/api/types/network"
 	"github.com/spf13/pflag"
-	cdi "tags.cncf.io/container-device-interface/pkg/parser"
 )
 
 const (
@@ -388,7 +387,7 @@ func parse(flags *pflag.FlagSet, copts *containerOptions, serverOS string) (*con
 	volumes := copts.volumes.GetMap()
 	// add any bind targets to the list of container volumes
 	for bind := range volumes {
-		parsed, err := loader.ParseVolume(bind)
+		parsed, err := ParseVolume(bind)
 		if err != nil {
 			return nil, err
 		}
@@ -396,7 +395,7 @@ func parse(flags *pflag.FlagSet, copts *containerOptions, serverOS string) (*con
 		if parsed.Source != "" {
 			toBind := bind
 
-			if parsed.Type == string(mount.TypeBind) {
+			if parsed.Type == mount.TypeBind {
 				if hostPart, targetPath, ok := strings.Cut(bind, ":"); ok {
 					if !filepath.IsAbs(hostPart) && strings.HasPrefix(hostPart, ".") {
 						if absHostPart, err := filepath.Abs(hostPart); err == nil {
@@ -504,7 +503,7 @@ func parse(flags *pflag.FlagSet, copts *containerOptions, serverOS string) (*con
 	deviceMappings := make([]container.DeviceMapping, 0, len(devices))
 	cdiDeviceNames := make([]string, 0, len(devices))
 	for _, device := range devices {
-		if cdi.IsQualifiedName(device) {
+		if cdiDeviceName.MatchString(device) {
 			cdiDeviceNames = append(cdiDeviceNames, device)
 			continue
 		}
@@ -1197,6 +1196,8 @@ func convertPortSet(ports nat.PortSet) (network.PortSet, error) {
 	return converted, nil
 }
 
+var cdiDeviceName = regexp.MustCompile(`^[a-zA-Z]([a-zA-Z0-9_.-]*[a-zA-Z0-9])?/[a-zA-Z]([a-zA-Z0-9_.-]*[a-zA-Z0-9])?=[a-zA-Z0-9]([a-zA-Z0-9_.:-]*[a-zA-Z0-9])?$`)
+
 func convertPortMap(bindings nat.PortMap) (network.PortMap, error) {
 	converted := make(network.PortMap, len(bindings))
 	for port, portBindings := range bindings {

act/container/docker_cli_test.go

@@ -25,13 +25,11 @@ import (
 	"testing"
 	"time"
 
-	"github.com/google/go-cmp/cmp/cmpopts"
 	"github.com/moby/moby/api/types/container"
 	networktypes "github.com/moby/moby/api/types/network"
 	"github.com/spf13/pflag"
-	"gotest.tools/v3/assert"
-	is "gotest.tools/v3/assert/cmp"
-	"gotest.tools/v3/skip"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )
 
 func mustParseMAC(s string) networktypes.HardwareAddr {
@@ -90,7 +88,7 @@ func setupRunFlags() (*pflag.FlagSet, *containerOptions) {
 func mustParse(t *testing.T, args string) (*container.Config, *container.HostConfig, *networktypes.NetworkingConfig) {
 	t.Helper()
 	config, hostConfig, nwConfig, err := parseRun(append(strings.Split(args, " "), "ubuntu", "bash"))
-	assert.NilError(t, err)
+	require.NoError(t, err)
 	return config, hostConfig, nwConfig
 }
 
@@ -156,12 +154,12 @@ func TestParseRunLinks(t *testing.T) {
 	for _, tc := range tests {
 		t.Run(tc.name, func(t *testing.T) {
 			_, hostConfig, netConfig := mustParse(t, tc.input)
-			assert.Check(t, is.DeepEqual(hostConfig.Links, tc.expHostConfigLinks))
-			assert.Check(t, is.Len(netConfig.EndpointsConfig, len(tc.expNetConfigLinks)))
+			assert.Equal(t, tc.expHostConfigLinks, hostConfig.Links)
+			assert.Len(t, netConfig.EndpointsConfig, len(tc.expNetConfigLinks))
 			for netName, expLinks := range tc.expNetConfigLinks {
 				nc, ok := netConfig.EndpointsConfig[netName]
-				assert.Assert(t, ok)
-				assert.Check(t, is.DeepEqual(nc.Links, expLinks))
+				require.True(t, ok)
+				assert.Equal(t, expLinks, nc.Links)
 			}
 		})
 	}
@@ -169,15 +167,15 @@ func TestParseRunLinks(t *testing.T) {
 
 func TestParseRunWithoutUmask(t *testing.T) {
 	_, hostConfig, _, err := parseRun([]string{"ubuntu", "bash"})
-	assert.NilError(t, err)
-	assert.Assert(t, hostConfig.Umask == nil)
+	require.NoError(t, err)
+	require.Nil(t, hostConfig.Umask)
 }
 
 func TestParseRunUmask(t *testing.T) {
 	_, hostConfig, _, err := parseRun([]string{"--umask", "0022", "ubuntu", "bash"})
-	assert.NilError(t, err)
-	assert.Assert(t, hostConfig.Umask != nil)
-	assert.Equal(t, uint32(0o22), *hostConfig.Umask)
+	require.NoError(t, err)
+	require.NotNil(t, hostConfig.Umask)
+	require.Equal(t, uint32(0o22), *hostConfig.Umask)
 }
 
 func TestParseRunAttach(t *testing.T) {
@@ -225,9 +223,9 @@ func TestParseRunAttach(t *testing.T) {
 	for _, tc := range tests {
 		t.Run(tc.input, func(t *testing.T) {
 			config, _, _ := mustParse(t, tc.input)
-			assert.Equal(t, config.AttachStdin, tc.expected.AttachStdin)
-			assert.Equal(t, config.AttachStdout, tc.expected.AttachStdout)
-			assert.Equal(t, config.AttachStderr, tc.expected.AttachStderr)
+			require.Equal(t, tc.expected.AttachStdin, config.AttachStdin)
+			require.Equal(t, tc.expected.AttachStdout, config.AttachStdout)
+			require.Equal(t, tc.expected.AttachStderr, config.AttachStderr)
 		})
 	}
 }
@@ -273,7 +271,7 @@ func TestParseRunWithInvalidArgs(t *testing.T) {
 	flags, _ := setupRunFlags()
 	for _, tc := range tests {
 		t.Run(strings.Join(tc.args, " "), func(t *testing.T) {
-			assert.Error(t, flags.Parse(tc.args), tc.error)
+			require.EqualError(t, flags.Parse(tc.args), tc.error)
 		})
 	}
 }
@@ -396,23 +394,23 @@ func TestRunFlagsParseWithMemory(t *testing.T) {
 	flags, _ := setupRunFlags()
 	args := []string{"--memory=invalid", "img", "cmd"}
 	err := flags.Parse(args)
-	assert.ErrorContains(t, err, `invalid argument "invalid" for "-m, --memory" flag`)
+	require.ErrorContains(t, err, `invalid argument "invalid" for "-m, --memory" flag`)
 
 	_, hostconfig, _ := mustParse(t, "--memory=1G")
-	assert.Check(t, is.Equal(int64(1073741824), hostconfig.Memory))
+	assert.Equal(t, int64(1073741824), hostconfig.Memory)
 }
 
 func TestParseWithMemorySwap(t *testing.T) {
 	flags, _ := setupRunFlags()
 	args := []string{"--memory-swap=invalid", "img", "cmd"}
 	err := flags.Parse(args)
-	assert.ErrorContains(t, err, `invalid argument "invalid" for "--memory-swap" flag`)
+	require.ErrorContains(t, err, `invalid argument "invalid" for "--memory-swap" flag`)
 
 	_, hostconfig, _ := mustParse(t, "--memory-swap=1G")
-	assert.Check(t, is.Equal(int64(1073741824), hostconfig.MemorySwap))
+	assert.Equal(t, int64(1073741824), hostconfig.MemorySwap)
 
 	_, hostconfig, _ = mustParse(t, "--memory-swap=-1")
-	assert.Check(t, is.Equal(int64(-1), hostconfig.MemorySwap))
+	assert.Equal(t, int64(-1), hostconfig.MemorySwap)
 }
 
 func TestParseHostname(t *testing.T) {
@@ -474,7 +472,7 @@ func TestParseWithExpose(t *testing.T) {
 		for expose, expectedError := range tests {
 			t.Run(expose, func(t *testing.T) {
 				_, _, _, err := parseRun([]string{fmt.Sprintf("--expose=%v", expose), "img", "cmd"})
-				assert.Error(t, err, expectedError)
+				require.EqualError(t, err, expectedError)
 			})
 		}
 	})
@@ -489,10 +487,10 @@ func TestParseWithExpose(t *testing.T) {
 		for expose, exposedPorts := range tests {
 			t.Run(expose, func(t *testing.T) {
 				config, _, _, err := parseRun([]string{fmt.Sprintf("--expose=%v", expose), "img", "cmd"})
-				assert.NilError(t, err)
+				require.NoError(t, err)
 				for _, port := range exposedPorts {
 					_, ok := config.ExposedPorts[port]
-					assert.Check(t, ok, "missing port %q in exposed ports: %#+v", port, config.ExposedPorts[port])
+					assert.True(t, ok, "missing port %q in exposed ports: %#+v", port, config.ExposedPorts[port])
 				}
 			})
 		}
@@ -501,18 +499,20 @@ func TestParseWithExpose(t *testing.T) {
 	t.Run("merge with published", func(t *testing.T) {
 		// Merge with actual published port
 		config, _, _, err := parseRun([]string{"--publish=80", "--expose=80-81/tcp", "img", "cmd"})
-		assert.NilError(t, err)
-		assert.Check(t, is.Len(config.ExposedPorts, 2))
+		require.NoError(t, err)
+		assert.Len(t, config.ExposedPorts, 2)
 		ports := []networktypes.Port{networktypes.MustParsePort("80/tcp"), networktypes.MustParsePort("81/tcp")}
 		for _, port := range ports {
 			_, ok := config.ExposedPorts[port]
-			assert.Check(t, ok, "missing port %q in exposed ports: %#+v", port, config.ExposedPorts[port])
+			assert.True(t, ok, "missing port %q in exposed ports: %#+v", port, config.ExposedPorts[port])
 		}
 	})
 }
 
 func TestParseDevice(t *testing.T) {
-	skip.If(t, runtime.GOOS != "linux") // Windows and macOS validate server-side
+	if runtime.GOOS != "linux" {
+		t.Skip("Windows and macOS validate server-side")
+	}
 	testCases := []struct {
 		devices        []string
 		deviceMapping  *container.DeviceMapping
@@ -586,17 +586,17 @@ func TestParseDevice(t *testing.T) {
 
 			_, hostconfig, _, err := parseRun(args)
 
-			assert.NilError(t, err)
+			require.NoError(t, err)
 
 			if tc.deviceMapping != nil {
-				if assert.Check(t, is.Len(hostconfig.Devices, 1)) {
-					assert.Check(t, is.DeepEqual(*tc.deviceMapping, hostconfig.Devices[0]))
+				if assert.Len(t, hostconfig.Devices, 1) {
+					assert.Equal(t, *tc.deviceMapping, hostconfig.Devices[0])
 				}
 			} else {
-				assert.Check(t, is.Len(hostconfig.Devices, 0))
+				assert.Empty(t, hostconfig.Devices)
 			}
 
-			assert.Check(t, is.DeepEqual(tc.deviceRequests, hostconfig.DeviceRequests))
+			assert.Equal(t, tc.deviceRequests, hostconfig.DeviceRequests)
 		})
 	}
 }
@@ -665,11 +665,11 @@ func TestParseDeviceByServerOS(t *testing.T) {
 		t.Run(tc.name, func(t *testing.T) {
 			got, err := parseDevice(tc.device, tc.serverOS)
 			if tc.wantErr != "" {
-				assert.Error(t, err, tc.wantErr)
+				require.EqualError(t, err, tc.wantErr)
 				return
 			}
-			assert.NilError(t, err)
-			assert.Equal(t, got, tc.want)
+			require.NoError(t, err)
+			require.Equal(t, tc.want, got)
 		})
 	}
 }
@@ -848,13 +848,13 @@ func TestParseNetworkConfig(t *testing.T) {
 			_, hConfig, nwConfig, err := parseRun(tc.flags)
 
 			if tc.expectedErr != "" {
-				assert.Error(t, err, tc.expectedErr)
+				require.EqualError(t, err, tc.expectedErr)
 				return
 			}
 
-			assert.NilError(t, err)
-			assert.DeepEqual(t, hConfig.NetworkMode, tc.expectedHostCfg.NetworkMode)
-			assert.DeepEqual(t, nwConfig.EndpointsConfig, tc.expected, cmpopts.EquateComparable(netip.Addr{}))
+			require.NoError(t, err)
+			require.Equal(t, tc.expectedHostCfg.NetworkMode, hConfig.NetworkMode)
+			require.Equal(t, tc.expected, nwConfig.EndpointsConfig)
 		})
 	}
 }
@@ -863,24 +863,24 @@ func TestParseModes(t *testing.T) {
 	// pid ko
 	flags, copts := setupRunFlags()
 	args := []string{"--pid=container:", "img", "cmd"}
-	assert.NilError(t, flags.Parse(args))
+	require.NoError(t, flags.Parse(args))
 	_, err := parse(flags, copts, runtime.GOOS)
-	assert.ErrorContains(t, err, "--pid: invalid PID mode")
+	require.ErrorContains(t, err, "--pid: invalid PID mode")
 
 	// pid ok
 	_, hostconfig, _, err := parseRun([]string{"--pid=host", "img", "cmd"})
-	assert.NilError(t, err)
+	require.NoError(t, err)
 	if !hostconfig.PidMode.Valid() {
 		t.Fatalf("Expected a valid PidMode, got %v", hostconfig.PidMode)
 	}
 
 	// uts ko
 	_, _, _, err = parseRun([]string{"--uts=container:", "img", "cmd"}) //nolint:dogsled // verbatim copy from docker/cli tests
-	assert.ErrorContains(t, err, "--uts: invalid UTS mode")
+	require.ErrorContains(t, err, "--uts: invalid UTS mode")
 
 	// uts ok
 	_, hostconfig, _, err = parseRun([]string{"--uts=host", "img", "cmd"})
-	assert.NilError(t, err)
+	require.NoError(t, err)
 	if !hostconfig.UTSMode.Valid() {
 		t.Fatalf("Expected a valid UTSMode, got %v", hostconfig.UTSMode)
 	}
@@ -892,11 +892,11 @@ func TestRunFlagsParseShmSize(t *testing.T) {
 	args := []string{"--shm-size=a128m", "img", "cmd"}
 	expectedErr := `invalid argument "a128m" for "--shm-size" flag:`
 	err := flags.Parse(args)
-	assert.ErrorContains(t, err, expectedErr)
+	require.ErrorContains(t, err, expectedErr)
 
 	// shm-size ok
 	_, hostconfig, _, err := parseRun([]string{"--shm-size=128m", "img", "cmd"})
-	assert.NilError(t, err)
+	require.NoError(t, err)
 	if hostconfig.ShmSize != 134217728 {
 		t.Fatalf("Expected a valid ShmSize, got %d", hostconfig.ShmSize)
 	}
@@ -967,11 +967,11 @@ func TestParseRestartPolicy(t *testing.T) {
 		t.Run(tc.input, func(t *testing.T) {
 			_, hostConfig, _, err := parseRun([]string{"--restart=" + tc.input, "img", "cmd"})
 			if tc.expectedErr != "" {
-				assert.Check(t, is.Error(err, tc.expectedErr))
-				assert.Check(t, is.Nil(hostConfig))
+				assert.Nil(t, hostConfig)
+				assert.EqualError(t, err, tc.expectedErr)
 			} else {
-				assert.NilError(t, err)
-				assert.Check(t, is.DeepEqual(hostConfig.RestartPolicy, tc.expected))
+				require.NoError(t, err)
+				assert.Equal(t, tc.expected, hostConfig.RestartPolicy)
 			}
 		})
 	}
@@ -980,7 +980,7 @@ func TestParseRestartPolicy(t *testing.T) {
 func TestParseRestartPolicyAutoRemove(t *testing.T) {
 	_, _, _, err := parseRun([]string{"--rm", "--restart=always", "img", "cmd"}) //nolint:dogsled // verbatim copy from docker/cli tests
 	const expected = "conflicting options: cannot specify both --restart and --rm"
-	assert.Check(t, is.Error(err, expected))
+	assert.EqualError(t, err, expected)
 }
 
 func TestParseHealth(t *testing.T) {
@@ -1118,12 +1118,14 @@ func TestParseLabelfileVariables(t *testing.T) { //nolint:dupl // verbatim copy
 
 func TestParseEntryPoint(t *testing.T) {
 	config, _, _, err := parseRun([]string{"--entrypoint=anything", "cmd", "img"})
-	assert.NilError(t, err)
-	assert.Check(t, is.DeepEqual(config.Entrypoint, []string{"anything"}))
+	require.NoError(t, err)
+	assert.Equal(t, []string{"anything"}, config.Entrypoint)
 }
 
 func TestValidateDevice(t *testing.T) {
-	skip.If(t, runtime.GOOS != "linux") // Windows and macOS validate server-side
+	if runtime.GOOS != "linux" {
+		t.Skip("Windows and macOS validate server-side")
+	}
 	valid := []string{
 		"/home",
 		"/home:/home",
@@ -1222,22 +1224,22 @@ func TestValidateDeviceByServerOS(t *testing.T) {
 		t.Run(tc.name, func(t *testing.T) {
 			got, err := validateDevice(tc.value, tc.serverOS)
 			if tc.wantError != "" {
-				assert.Error(t, err, tc.wantError)
+				require.EqualError(t, err, tc.wantError)
 				return
 			}
-			assert.NilError(t, err)
-			assert.Equal(t, got, tc.want)
+			require.NoError(t, err)
+			require.Equal(t, tc.want, got)
 		})
 	}
 }
 
 func TestDeviceCgroupRulesAndInvalidParameter(t *testing.T) {
 	got, err := validateDeviceCgroupRule("c 1:3 rwm")
-	assert.NilError(t, err)
-	assert.Equal(t, got, "c 1:3 rwm")
+	require.NoError(t, err)
+	require.Equal(t, "c 1:3 rwm", got)
 
 	_, err = validateDeviceCgroupRule("invalid")
-	assert.Error(t, err, "invalid device cgroup format 'invalid'")
+	require.EqualError(t, err, "invalid device cgroup format 'invalid'")
 
 	if invalidParameter(nil) != nil {
 		t.Fatal("invalidParameter(nil) should be nil")
@@ -1245,9 +1247,9 @@ func TestDeviceCgroupRulesAndInvalidParameter(t *testing.T) {
 	cause := errors.New("bad input")
 	err = invalidParameter(cause)
 	var invalid interface{ InvalidParameter() }
-	assert.Assert(t, errors.As(err, &invalid))
-	assert.Assert(t, errors.Is(err, cause))
-	assert.Equal(t, invalidParameter(err), err) // already invalid, so not wrapped twice
+	require.ErrorAs(t, err, &invalid)
+	require.ErrorIs(t, err, cause)
+	require.Condition(t, func() bool { return invalidParameter(err) == err })
 }
 
 func TestParseSystemPaths(t *testing.T) {
@@ -1298,9 +1300,9 @@ func TestParseSystemPaths(t *testing.T) {
 
 	for _, tc := range tests {
 		securityOpts, maskedPaths, readonlyPaths := parseSystemPaths(tc.in)
-		assert.DeepEqual(t, securityOpts, tc.out)
-		assert.DeepEqual(t, maskedPaths, tc.masked)
-		assert.DeepEqual(t, readonlyPaths, tc.readonly)
+		require.Equal(t, tc.out, securityOpts)
+		require.Equal(t, tc.masked, maskedPaths)
+		require.Equal(t, tc.readonly, readonlyPaths)
 	}
 }
 
@@ -1322,9 +1324,9 @@ func TestConvertToStandardNotation(t *testing.T) {
 	for key, ports := range valid {
 		convertedPorts, err := convertToStandardNotation(ports)
 		if err != nil {
-			assert.NilError(t, err)
+			require.NoError(t, err)
 		}
-		assert.DeepEqual(t, strings.Split(key, " "), convertedPorts)
+		require.Equal(t, strings.Split(key, " "), convertedPorts)
 	}
 
 	for _, ports := range invalid {

act/container/docker_pull_test.go

@@ -12,7 +12,6 @@ import (
 	"gitea.com/gitea/runner/act/common/logging"
 	"gitea.com/gitea/runner/act/common/logging/logtest"
 
-	"github.com/docker/cli/cli/config"
 	assert "github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
@@ -44,10 +43,7 @@ func TestCleanImage(t *testing.T) {
 func TestGetImagePullOptions(t *testing.T) {
 	ctx := t.Context()
 
-	orig := config.Dir()
-	t.Cleanup(func() { config.SetDir(orig) })
-
-	config.SetDir("/non-existent/docker")
+	t.Setenv("DOCKER_CONFIG", "/non-existent/docker")
 
 	options, err := getImagePullOptions(ctx, NewDockerPullExecutorInput{})
 	assert.NoError(t, err, "Failed to create ImagePullOptions")                                                 //nolint:testifylint // pre-existing issue from nektos/act
@@ -61,7 +57,7 @@ func TestGetImagePullOptions(t *testing.T) {
 	assert.NoError(t, err, "Failed to create ImagePullOptions") //nolint:testifylint // pre-existing issue from nektos/act
 	assert.Equal(t, "eyJ1c2VybmFtZSI6InVzZXJuYW1lIiwicGFzc3dvcmQiOiJwYXNzd29yZCJ9", options.RegistryAuth, "Username and Password should be provided")
 
-	config.SetDir("testdata/docker-pull-options")
+	t.Setenv("DOCKER_CONFIG", "testdata/docker-pull-options")
 
 	options, err = getImagePullOptions(ctx, NewDockerPullExecutorInput{
 		Image: "nektos/act",

act/container/docker_run.go

@@ -13,6 +13,7 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"net"
 	"os"
 	"path"
 	"path/filepath"
@@ -27,11 +28,8 @@ import (
 	"gitea.com/gitea/runner/act/common"
 	"gitea.com/gitea/runner/act/common/logging"
 
-	"dario.cat/mergo"
 	"github.com/bmatcuk/doublestar/v4"
 	cerrdefs "github.com/containerd/errdefs"
-	"github.com/docker/cli/cli/compose/loader"
-	"github.com/docker/cli/cli/connhelper"
 	"github.com/docker/cli/opts"
 	"github.com/moby/moby/api/pkg/stdcopy"
 	"github.com/moby/moby/api/types/container"
@@ -372,15 +370,13 @@ func GetDockerClient(ctx context.Context) (cli client.APIClient, err error) {
 	dockerHost := os.Getenv("DOCKER_HOST")
 
 	if strings.HasPrefix(dockerHost, "ssh://") {
-		var helper *connhelper.ConnectionHelper
-
-		helper, err = connhelper.GetConnectionHelper(dockerHost)
-		if err != nil {
+		var args []string
+		if args, err = sshArgs(dockerHost); err != nil {
 			return nil, err
 		}
 		cli, err = client.New(
-			client.WithHost(helper.Host),
-			client.WithDialContext(helper.Dialer),
+			client.WithHost("http://docker.example.com"), // the dialer below ignores the address
+			client.WithDialContext(func(context.Context, string, string) (net.Conn, error) { return dialCommand("ssh", args...) }),
 		)
 	} else {
 		cli, err = client.New(client.FromEnv)
@@ -622,10 +618,7 @@ func (cr *containerReference) mergeContainerConfigs(ctx context.Context, config
 
 	logger.Debugf("Custom container.Config from options ==> %+v", containerConfig.Config)
 
-	err = mergo.Merge(config, containerConfig.Config, mergo.WithOverride, mergo.WithAppendSlice)
-	if err != nil {
-		return nil, nil, fmt.Errorf("cannot merge container.Config options: '%s': '%w'", options, err)
-	}
+	overlay(reflect.ValueOf(config).Elem(), reflect.ValueOf(containerConfig.Config).Elem(), true)
 	logger.Debugf("Merged container.Config ==> %+v", config)
 
 	logger.Debugf("Custom container.HostConfig from options ==> %+v", containerConfig.HostConfig)
@@ -635,10 +628,7 @@ func (cr *containerReference) mergeContainerConfigs(ctx context.Context, config
 	binds := hostConfig.Binds
 	mounts := hostConfig.Mounts
 	networkMode := hostConfig.NetworkMode
-	err = mergo.Merge(hostConfig, containerConfig.HostConfig, mergo.WithOverride)
-	if err != nil {
-		return nil, nil, fmt.Errorf("cannot merge container.HostConfig options: '%s': '%w'", options, err)
-	}
+	overlay(reflect.ValueOf(hostConfig).Elem(), reflect.ValueOf(containerConfig.HostConfig).Elem(), false)
 	hostConfig.Binds = binds
 	hostConfig.Mounts = mounts
 	if cf.name != "" {
@@ -1117,7 +1107,7 @@ func (cr *containerReference) sanitizeConfig(ctx context.Context, config *contai
 		// sanitize binds
 		sanitizedBinds := make([]string, 0, len(hostConfig.Binds))
 		for _, bind := range hostConfig.Binds {
-			parsed, err := loader.ParseVolume(bind)
+			parsed, err := ParseVolume(bind)
 			if err != nil {
 				logger.Warnf("parse volume [%s] error: %v", bind, err)
 				continue
@@ -1127,8 +1117,8 @@ func (cr *containerReference) sanitizeConfig(ctx context.Context, config *contai
 				sanitizedBinds = append(sanitizedBinds, bind)
 				continue
 			}
-			if matcher.isValid(parsed.Source, mount.Type(parsed.Type), parsed.ReadOnly) {
-				if matcher.needsNoCopy(parsed.Source, mount.Type(parsed.Type)) && (parsed.Volume == nil || !parsed.Volume.NoCopy) {
+			if matcher.isValid(parsed.Source, parsed.Type, parsed.ReadOnly) {
+				if matcher.needsNoCopy(parsed.Source, parsed.Type) && !parsed.NoCopy {
 					bind += ",nocopy"
 				}
 				sanitizedBinds = append(sanitizedBinds, bind)
@@ -1168,9 +1158,56 @@ func SanitizeBinds(ctx context.Context, validVolumes, binds []string) []string {
 	return hostConfig.Binds
 }
 
+func overlay(dst, src reflect.Value, appendSlices bool) {
+	switch dst.Kind() {
+	case reflect.Struct:
+		opaque := true
+		for i := range dst.NumField() {
+			if dst.Type().Field(i).IsExported() {
+				opaque = false
+				overlay(dst.Field(i), src.Field(i), appendSlices)
+			}
+		}
+		if opaque {
+			dst.Set(src)
+		}
+	case reflect.Map:
+		if src.IsNil() {
+			return
+		}
+		if dst.IsNil() {
+			dst.Set(reflect.MakeMap(dst.Type()))
+		}
+		for key, value := range src.Seq2() {
+			dst.SetMapIndex(key, value)
+		}
+	case reflect.Slice:
+		if appendSlices {
+			dst.Set(reflect.AppendSlice(dst, src))
+		} else if src.Len() > 0 {
+			dst.Set(src)
+		}
+	case reflect.Pointer:
+		if src.IsNil() {
+			return
+		}
+		if dst.IsNil() {
+			dst.Set(src)
+			return
+		}
+		overlay(dst.Elem(), src.Elem(), appendSlices)
+	case reflect.Array:
+		dst.Set(src)
+	default:
+		if !src.IsZero() {
+			dst.Set(src)
+		}
+	}
+}
+
 // bindTarget returns the container path a bind mounts onto, empty if it cannot be parsed.
 func bindTarget(bind string) string {
-	parsed, err := loader.ParseVolume(bind)
+	parsed, err := ParseVolume(bind)
 	if err != nil {
 		return ""
 	}

act/container/docker_ssh.go

@@ -0,0 +1,111 @@
+// Copyright 2026 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+//go:build !(WITHOUT_DOCKER || !(linux || darwin || windows || netbsd))
+
+package container
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
+	"net"
+	"os/exec"
+	"strings"
+	"sync"
+	"syscall"
+	"time"
+
+	"github.com/docker/cli/cli/connhelper/ssh"
+)
+
+func sshArgs(daemonURL string) ([]string, error) {
+	spec, err := ssh.ParseURL(daemonURL)
+	if err != nil {
+		return nil, err
+	}
+	remote := []string{"docker", "system", "dial-stdio"}
+	if strings.Trim(spec.Path, "/") != "" {
+		remote = []string{"docker", "--host=unix://" + spec.Path, "system", "dial-stdio"}
+	}
+	return spec.Command([]string{"-o", "ConnectTimeout=30", "-T"}, remote...)
+}
+
+func dialCommand(name string, args ...string) (net.Conn, error) {
+	conn := &commandConn{cmd: exec.Command(name, args...)}
+	conn.cmd.SysProcAttr = sshSysProcAttr() // a session of its own like docker's, so a ProxyCommand never reads the runner's terminal: https://github.com/docker/cli/issues/1707
+	conn.cmd.Stderr = &conn.stderr
+	conn.cmd.WaitDelay = time.Second // a ProxyCommand child keeping stderr open would otherwise block Wait after ssh exits
+	conn.wait = sync.OnceValue(func() error {
+		if err := conn.cmd.Wait(); err != nil && !errors.Is(err, exec.ErrWaitDelay) {
+			return fmt.Errorf("%s: %w: %s", strings.Join(conn.cmd.Args, " "), err, strings.TrimSpace(conn.stderr.String()))
+		}
+		return nil
+	})
+	var err error
+	if conn.stdin, err = conn.cmd.StdinPipe(); err != nil {
+		return nil, err
+	}
+	if conn.stdout, err = conn.cmd.StdoutPipe(); err != nil {
+		return nil, err
+	}
+	return conn, conn.cmd.Start()
+}
+
+type commandConn struct {
+	cmd    *exec.Cmd
+	stdin  io.WriteCloser
+	stdout io.ReadCloser
+	stderr cappedBuffer
+	wait   func() error
+}
+
+func (c *commandConn) waitWithin(timeout time.Duration) error {
+	timer := time.AfterFunc(timeout, func() { _ = c.cmd.Process.Kill() })
+	defer timer.Stop()
+	return c.wait()
+}
+
+func (c *commandConn) Read(p []byte) (int, error) {
+	n, err := c.stdout.Read(p)
+	if errors.Is(err, io.EOF) {
+		if waitErr := c.waitWithin(10 * time.Second); waitErr != nil {
+			return n, waitErr
+		}
+	}
+	return n, err
+}
+
+func (c *commandConn) Write(p []byte) (int, error) { return c.stdin.Write(p) }
+
+// CloseWrite lets the daemon see the end of a hijacked stream, like a TCP half-close.
+func (c *commandConn) CloseWrite() error { return c.stdin.Close() }
+
+func (c *commandConn) Close() error {
+	_ = c.stdin.Close()
+	if c.cmd.Process.Signal(syscall.SIGTERM) != nil { // SIGTERM lets ssh take its ProxyCommand down, Windows only kills
+		_ = c.cmd.Process.Kill()
+	}
+	_ = c.waitWithin(3 * time.Second)
+	return nil
+}
+
+func (c *commandConn) LocalAddr() net.Addr { return &net.UnixAddr{Name: "stdio", Net: "unix"} }
+
+func (c *commandConn) RemoteAddr() net.Addr { return &net.UnixAddr{Name: "stdio", Net: "unix"} }
+
+func (c *commandConn) SetDeadline(_deadline time.Time) error { return nil }
+
+func (c *commandConn) SetReadDeadline(_deadline time.Time) error { return nil }
+
+func (c *commandConn) SetWriteDeadline(_deadline time.Time) error { return nil }
+
+type cappedBuffer struct{ bytes.Buffer }
+
+func (b *cappedBuffer) Write(p []byte) (int, error) {
+	if b.Len() > 4096 {
+		b.Reset()
+	}
+	return b.Buffer.Write(p)
+}

act/container/docker_ssh_linux.go

@@ -0,0 +1,12 @@
+// Copyright 2026 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+//go:build !WITHOUT_DOCKER
+
+package container
+
+import "syscall"
+
+func sshSysProcAttr() *syscall.SysProcAttr {
+	return &syscall.SysProcAttr{Setsid: true, Pdeathsig: syscall.SIGKILL}
+}

act/container/docker_ssh_test.go

@@ -0,0 +1,51 @@
+// Copyright 2026 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+//go:build !(WITHOUT_DOCKER || !(linux || darwin || windows || netbsd))
+
+package container
+
+import (
+	"io"
+	"os/exec"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestSSHArgs(t *testing.T) {
+	args, err := sshArgs("ssh://me@host:2222/run/user/1000/my docker.sock")
+	require.NoError(t, err)
+	assert.Equal(t, []string{"-l", "me", "-p", "2222", "-o", "ConnectTimeout=30", "-T", "--", "host", "docker '--host=unix:///run/user/1000/my docker.sock' system dial-stdio"}, args)
+
+	args, err = sshArgs("ssh://[::1]")
+	require.NoError(t, err)
+	assert.Equal(t, []string{"-o", "ConnectTimeout=30", "-T", "--", "::1", "docker system dial-stdio"}, args)
+
+	for _, invalid := range []string{"ssh://me:secret@host", "ssh://host?x=1", "ssh://host#x", "ssh://"} {
+		_, err := sshArgs(invalid)
+		assert.Error(t, err, invalid)
+	}
+}
+
+func TestDialCommandStreamsStdioAndReportsExit(t *testing.T) {
+	if _, err := exec.LookPath("sh"); err != nil {
+		t.Skip("needs a POSIX shell")
+	}
+	conn, err := dialCommand("sh", "-c", "cat")
+	require.NoError(t, err)
+	_, err = conn.Write([]byte("ping"))
+	require.NoError(t, err)
+	require.NoError(t, conn.(interface{ CloseWrite() error }).CloseWrite())
+	echoed, err := io.ReadAll(conn)
+	require.NoError(t, err)
+	assert.Equal(t, "ping", string(echoed))
+	require.NoError(t, conn.Close())
+
+	conn, err = dialCommand("sh", "-c", "exec 3<&0; cat <&3 >/dev/null & echo 'no route to host' >&2; exit 255")
+	require.NoError(t, err)
+	_, err = io.ReadAll(conn)
+	require.ErrorContains(t, err, "no route to host")
+	require.NoError(t, conn.Close())
+}

act/container/docker_ssh_unix.go

@@ -0,0 +1,12 @@
+// Copyright 2026 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+//go:build !WITHOUT_DOCKER && (darwin || netbsd)
+
+package container
+
+import "syscall"
+
+func sshSysProcAttr() *syscall.SysProcAttr {
+	return &syscall.SysProcAttr{Setsid: true}
+}

act/container/docker_ssh_windows.go

@@ -0,0 +1,10 @@
+// Copyright 2026 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+//go:build !WITHOUT_DOCKER
+
+package container
+
+import "syscall"
+
+func sshSysProcAttr() *syscall.SysProcAttr { return nil }

act/container/volume_spec.go

@@ -0,0 +1,85 @@
+// Copyright 2026 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package container
+
+import (
+	"errors"
+	"fmt"
+	"slices"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+
+	"github.com/moby/moby/api/types/mount"
+)
+
+type VolumeSpec struct {
+	Type     mount.Type
+	Source   string
+	Target   string
+	ReadOnly bool
+	NoCopy   bool
+}
+
+// ParseVolume parses spec like `docker run -v` does, without knowing the target platform.
+func ParseVolume(spec string) (VolumeSpec, error) {
+	switch len(spec) {
+	case 0:
+		return VolumeSpec{}, errors.New("invalid empty volume spec")
+	case 1, 2:
+		return VolumeSpec{Type: mount.TypeVolume, Target: spec}, nil
+	}
+
+	spec = string([]rune(spec)) // each invalid UTF-8 byte becomes U+FFFD, as in the JSON the daemon receives
+	var parts []string
+	for rest := spec; ; {
+		start := 0
+		if hasDriveLetter(rest) {
+			start = strings.IndexByte(rest, ':') + 1
+		}
+		end := strings.IndexByte(rest[start:], ':')
+		if end < 0 {
+			parts = append(parts, rest)
+			break
+		}
+		parts = append(parts, rest[:start+end])
+		rest = rest[start+end+1:]
+	}
+	if len(parts) > 3 {
+		return VolumeSpec{}, fmt.Errorf("invalid spec: %s: too many colons", spec)
+	}
+	if slices.Contains(parts, "") {
+		return VolumeSpec{}, fmt.Errorf("invalid spec: %s: empty section between colons", spec)
+	}
+
+	volume := VolumeSpec{Type: mount.TypeVolume, Target: parts[0]}
+	if len(parts) > 1 {
+		volume.Source, volume.Target = parts[0], parts[1]
+		if isHostPath(volume.Source) {
+			volume.Type = mount.TypeBind
+		}
+	}
+	if len(parts) == 3 {
+		for option := range strings.SplitSeq(parts[2], ",") {
+			switch option {
+			case "ro":
+				volume.ReadOnly = true
+			case "rw":
+				volume.ReadOnly = false
+			case "nocopy":
+				volume.NoCopy = true
+			}
+		}
+	}
+	return volume, nil
+}
+
+func hasDriveLetter(s string) bool {
+	letter, size := utf8.DecodeRuneInString(s)
+	return size < len(s) && s[size] == ':' && unicode.IsLetter(letter)
+}
+
+func isHostPath(source string) bool {
+	return strings.ContainsAny(source[:1], "./~") || strings.HasPrefix(source, `\\`) || hasDriveLetter(source)
+}

act/container/volume_spec_test.go

@@ -0,0 +1,18 @@
+// Copyright 2026 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package container
+
+import (
+	"testing"
+
+	"github.com/moby/moby/api/types/mount"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestParseVolumeReplacesInvalidUTF8LikeTheDaemonSees(t *testing.T) {
+	parsed, err := ParseVolume("/data/\xff\xfe:/mnt:ro")
+	require.NoError(t, err)
+	assert.Equal(t, VolumeSpec{Type: mount.TypeBind, Source: "/data/��", Target: "/mnt", ReadOnly: true}, parsed)
+}