Merge pull request moby#5067 from tonistiigi/dockerfile-mem-cleanup

dockerfile: cleanup of memory allocations

Author: AkihiroSuda

client/llb/meta.go

@@ -5,6 +5,8 @@ import (
 	"fmt"
 	"net"
 	"path"
+	"slices"
+	"sync"
 
 	"github.com/containerd/containerd/platforms"
 	"github.com/google/shlex"
@@ -111,16 +113,16 @@ func Reset(other State) StateOption {
 	}
 }
 
-func getEnv(s State) func(context.Context, *Constraints) (EnvList, error) {
-	return func(ctx context.Context, c *Constraints) (EnvList, error) {
+func getEnv(s State) func(context.Context, *Constraints) (*EnvList, error) {
+	return func(ctx context.Context, c *Constraints) (*EnvList, error) {
 		v, err := s.getValue(keyEnv)(ctx, c)
 		if err != nil {
 			return nil, err
 		}
 		if v != nil {
-			return v.(EnvList), nil
+			return v.(*EnvList), nil
 		}
-		return EnvList{}, nil
+		return &EnvList{}, nil
 	}
 }
 
@@ -346,54 +348,83 @@ func getSecurity(s State) func(context.Context, *Constraints) (pb.SecurityMode,
 	}
 }
 
-type EnvList []KeyValue
-
-type KeyValue struct {
-	key   string
-	value string
+type EnvList struct {
+	parent *EnvList
+	key    string
+	value  string
+	del    bool
+	once   sync.Once
+	l      int
+	values map[string]string
+	keys   []string
 }
 
-func (e EnvList) AddOrReplace(k, v string) EnvList {
-	e = e.Delete(k)
-	e = append(e, KeyValue{key: k, value: v})
-	return e
+func (e *EnvList) AddOrReplace(k, v string) *EnvList {
+	return &EnvList{
+		parent: e,
+		key:    k,
+		value:  v,
+		l:      e.l + 1,
+	}
 }
 
-func (e EnvList) SetDefault(k, v string) EnvList {
+func (e *EnvList) SetDefault(k, v string) *EnvList {
 	if _, ok := e.Get(k); !ok {
-		e = append(e, KeyValue{key: k, value: v})
+		return e.AddOrReplace(k, v)
 	}
 	return e
 }
 
-func (e EnvList) Delete(k string) EnvList {
-	e = append([]KeyValue(nil), e...)
-	if i, ok := e.Index(k); ok {
-		return append(e[:i], e[i+1:]...)
+func (e *EnvList) Delete(k string) EnvList {
+	return EnvList{
+		parent: e,
+		key:    k,
+		del:    true,
+		l:      e.l + 1,
 	}
-	return e
 }
 
-func (e EnvList) Get(k string) (string, bool) {
-	if index, ok := e.Index(k); ok {
-		return e[index].value, true
-	}
-	return "", false
+func (e *EnvList) makeValues() {
+	m := make(map[string]string, e.l)
+	seen := make(map[string]struct{}, e.l)
+	keys := make([]string, 0, e.l)
+	e.keys = e.addValue(keys, m, seen)
+	e.values = m
+	slices.Reverse(e.keys)
 }
 
-func (e EnvList) Index(k string) (int, bool) {
-	for i, kv := range e {
-		if kv.key == k {
-			return i, true
-		}
+func (e *EnvList) addValue(keys []string, vals map[string]string, seen map[string]struct{}) []string {
+	if e.parent == nil {
+		return keys
 	}
-	return -1, false
+	if _, ok := seen[e.key]; !e.del && !ok {
+		vals[e.key] = e.value
+		keys = append(keys, e.key)
+	}
+	seen[e.key] = struct{}{}
+	if e.parent != nil {
+		keys = e.parent.addValue(keys, vals, seen)
+	}
+	return keys
+}
+
+func (e *EnvList) Get(k string) (string, bool) {
+	e.once.Do(e.makeValues)
+	v, ok := e.values[k]
+	return v, ok
+}
+
+func (e *EnvList) Keys() []string {
+	e.once.Do(e.makeValues)
+	return e.keys
 }
 
-func (e EnvList) ToArray() []string {
-	out := make([]string, 0, len(e))
-	for _, kv := range e {
-		out = append(out, kv.key+"="+kv.value)
+func (e *EnvList) ToArray() []string {
+	keys := e.Keys()
+	out := make([]string, 0, len(keys))
+	for _, k := range keys {
+		v, _ := e.Get(k)
+		out = append(out, k+"="+v)
 	}
 	return out
 }

client/llb/state.go

@@ -351,16 +351,12 @@ func (s State) GetEnv(ctx context.Context, key string, co ...ConstraintsOpt) (st
 
 // Env returns a new [State] with the provided environment variable set.
 // See [Env]
-func (s State) Env(ctx context.Context, co ...ConstraintsOpt) ([]string, error) {
+func (s State) Env(ctx context.Context, co ...ConstraintsOpt) (*EnvList, error) {
 	c := &Constraints{}
 	for _, f := range co {
 		f.SetConstraintsOption(c)
 	}
-	env, err := getEnv(s)(ctx, c)
-	if err != nil {
-		return nil, err
-	}
-	return env.ToArray(), nil
+	return getEnv(s)(ctx, c)
 }
 
 // GetDir returns the current working directory for the state.

cmd/buildctl/build/exportcache.go

@@ -1,21 +1,20 @@
 package build
 
 import (
-	"encoding/csv"
 	"strings"
 
 	"github.com/moby/buildkit/client"
 	"github.com/moby/buildkit/util/bklog"
 	"github.com/pkg/errors"
+	"github.com/tonistiigi/go-csvvalue"
 )
 
 func parseExportCacheCSV(s string) (client.CacheOptionsEntry, error) {
 	ex := client.CacheOptionsEntry{
 		Type:  "",
 		Attrs: map[string]string{},
 	}
-	csvReader := csv.NewReader(strings.NewReader(s))
-	fields, err := csvReader.Read()
+	fields, err := csvvalue.Fields(s, nil)
 	if err != nil {
 		return ex, err
 	}

cmd/buildctl/build/importcache.go

@@ -1,21 +1,20 @@
 package build
 
 import (
-	"encoding/csv"
 	"strings"
 
 	"github.com/moby/buildkit/client"
 	"github.com/moby/buildkit/util/bklog"
 	"github.com/pkg/errors"
+	"github.com/tonistiigi/go-csvvalue"
 )
 
 func parseImportCacheCSV(s string) (client.CacheOptionsEntry, error) {
 	im := client.CacheOptionsEntry{
 		Type:  "",
 		Attrs: map[string]string{},
 	}
-	csvReader := csv.NewReader(strings.NewReader(s))
-	fields, err := csvReader.Read()
+	fields, err := csvvalue.Fields(s, nil)
 	if err != nil {
 		return im, err
 	}

cmd/buildctl/build/output.go

@@ -1,7 +1,6 @@
 package build
 
 import (
-	"encoding/csv"
 	"io"
 	"os"
 	"strconv"
@@ -11,6 +10,7 @@ import (
 	"github.com/moby/buildkit/client"
 	"github.com/moby/buildkit/session/filesync"
 	"github.com/pkg/errors"
+	"github.com/tonistiigi/go-csvvalue"
 )
 
 // parseOutputCSV parses a single --output CSV string
@@ -19,8 +19,7 @@ func parseOutputCSV(s string) (client.ExportEntry, error) {
 		Type:  "",
 		Attrs: map[string]string{},
 	}
-	csvReader := csv.NewReader(strings.NewReader(s))
-	fields, err := csvReader.Read()
+	fields, err := csvvalue.Fields(s, nil)
 	if err != nil {
 		return ex, err
 	}

cmd/buildctl/build/registryauthtlscontext.go

@@ -1,12 +1,12 @@
 package build
 
 import (
-	"encoding/csv"
 	"strconv"
 	"strings"
 
 	"github.com/moby/buildkit/session/auth/authprovider"
 	"github.com/pkg/errors"
+	"github.com/tonistiigi/go-csvvalue"
 )
 
 type authTLSContextEntry struct {
@@ -19,8 +19,7 @@ type authTLSContextEntry struct {
 
 func parseRegistryAuthTLSContextCSV(s string) (authTLSContextEntry, error) {
 	authTLSContext := authTLSContextEntry{}
-	csvReader := csv.NewReader(strings.NewReader(s))
-	fields, err := csvReader.Read()
+	fields, err := csvvalue.Fields(s, nil)
 	if err != nil {
 		return authTLSContext, err
 	}

cmd/buildctl/build/secret.go

@@ -1,12 +1,12 @@
 package build
 
 import (
-	"encoding/csv"
 	"strings"
 
 	"github.com/moby/buildkit/session"
 	"github.com/moby/buildkit/session/secrets/secretsprovider"
 	"github.com/pkg/errors"
+	"github.com/tonistiigi/go-csvvalue"
 )
 
 // ParseSecret parses --secret
@@ -27,8 +27,7 @@ func ParseSecret(sl []string) (session.Attachable, error) {
 }
 
 func parseSecret(val string) (*secretsprovider.Source, error) {
-	csvReader := csv.NewReader(strings.NewReader(val))
-	fields, err := csvReader.Read()
+	fields, err := csvvalue.Fields(val, nil)
 	if err != nil {
 		return nil, errors.Wrap(err, "failed to parse csv secret")
 	}

frontend/attestations/parse.go

@@ -1,10 +1,10 @@
 package attestations
 
 import (
-	"encoding/csv"
 	"strings"
 
 	"github.com/pkg/errors"
+	"github.com/tonistiigi/go-csvvalue"
 )
 
 const (
@@ -63,8 +63,7 @@ func Parse(values map[string]string) (map[string]map[string]string, error) {
 		if v == "" {
 			continue
 		}
-		csvReader := csv.NewReader(strings.NewReader(v))
-		fields, err := csvReader.Read()
+		fields, err := csvvalue.Fields(v, nil)
 		if err != nil {
 			return nil, errors.Wrapf(err, "failed to parse %s", k)
 		}