daemon: use lazyregexp to compile regexes on first use

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

daemon/events/testutils/testutils.go

@@ -2,26 +2,25 @@ package testutils // import "github.com/docker/docker/daemon/events/testutils"
 
 import (
 	"fmt"
-	"regexp"
 	"strings"
 	"time"
 
 	"github.com/docker/docker/api/types/events"
 	timetypes "github.com/docker/docker/api/types/time"
+	"github.com/docker/docker/internal/lazyregexp"
 )
 
-var (
+const (
 	reTimestamp  = `(?P<timestamp>\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}.\d{9}(:?(:?(:?-|\+)\d{2}:\d{2})|Z))`
 	reEventType  = `(?P<eventType>\w+)`
 	reAction     = `(?P<action>\w+)`
 	reID         = `(?P<id>[^\s]+)`
 	reAttributes = `(\s\((?P<attributes>[^\)]+)\))?`
-	reString     = fmt.Sprintf(`\A%s\s%s\s%s\s%s%s\z`, reTimestamp, reEventType, reAction, reID, reAttributes)
-
-	// eventCliRegexp is a regular expression that matches all possible event outputs in the cli
-	eventCliRegexp = regexp.MustCompile(reString)
 )
 
+// eventCliRegexp is a regular expression that matches all possible event outputs in the cli
+var eventCliRegexp = lazyregexp.New(fmt.Sprintf(`\A%s\s%s\s%s\s%s%s\z`, reTimestamp, reEventType, reAction, reID, reAttributes))
+
 // ScanMap turns an event string like the default ones formatted in the cli output
 // and turns it into map.
 func ScanMap(text string) map[string]string {

daemon/logger/journald/internal/fake/sender.go

@@ -15,13 +15,13 @@ import (
 	"fmt"
 	"os"
 	"os/exec"
-	"regexp"
 	"strconv"
 	"testing"
 	"time"
 
 	"code.cloudfoundry.org/clock"
 	"github.com/coreos/go-systemd/v22/journal"
+	"github.com/docker/docker/internal/lazyregexp"
 	"github.com/google/uuid"
 	"gotest.tools/v3/assert"
 
@@ -109,7 +109,7 @@ func NewT(t *testing.T, outpath string) *Sender {
 	return s
 }
 
-var validVarName = regexp.MustCompile("^[A-Z0-9][A-Z0-9_]*$")
+var validVarName = lazyregexp.New("^[A-Z0-9][A-Z0-9_]*$")
 
 // Send is a drop-in replacement for
 // github.com/coreos/go-systemd/v22/journal.Send.

daemon/prune.go

@@ -2,7 +2,6 @@ package daemon // import "github.com/docker/docker/daemon"
 
 import (
 	"context"
-	"regexp"
 	"strconv"
 	"time"
 
@@ -15,6 +14,7 @@ import (
 	timetypes "github.com/docker/docker/api/types/time"
 	networkSettings "github.com/docker/docker/daemon/network"
 	"github.com/docker/docker/errdefs"
+	"github.com/docker/docker/internal/lazyregexp"
 	"github.com/docker/docker/libnetwork"
 	"github.com/pkg/errors"
 )
@@ -136,6 +136,8 @@ func (daemon *Daemon) localNetworksPrune(ctx context.Context, pruneFilters filte
 	return rep
 }
 
+var networkIsInUse = lazyregexp.New(`network ([[:alnum:]]+) is in use`)
+
 // clusterNetworksPrune removes unused cluster networks
 func (daemon *Daemon) clusterNetworksPrune(ctx context.Context, pruneFilters filters.Args) (*network.PruneReport, error) {
 	rep := &network.PruneReport{}
@@ -152,7 +154,7 @@ func (daemon *Daemon) clusterNetworksPrune(ctx context.Context, pruneFilters fil
 	if err != nil {
 		return rep, err
 	}
-	networkIsInUse := regexp.MustCompile(`network ([[:alnum:]]+) is in use`)
+
 	for _, nw := range networks {
 		select {
 		case <-ctx.Done():

daemon/top_unix.go

@@ -7,24 +7,26 @@ import (
 	"context"
 	"fmt"
 	"os/exec"
-	"regexp"
 	"strconv"
 	"strings"
 
 	"github.com/docker/docker/api/types/container"
 	"github.com/docker/docker/api/types/events"
 	"github.com/docker/docker/errdefs"
+	"github.com/docker/docker/internal/lazyregexp"
 	libcontainerdtypes "github.com/docker/docker/libcontainerd/types"
 	"github.com/pkg/errors"
 )
 
+// NOTE: \\s does not detect unicode whitespaces.
+// So we use fieldsASCII instead of strings.Fields in parsePSOutput.
+// See https://github.com/docker/docker/pull/24358
+//
+//nolint:gosimple
+var psArgsRegexp = lazyregexp.New("\\s+([^\\s]*)=\\s*(PID[^\\s]*)")
+
 func validatePSArgs(psArgs string) error {
-	// NOTE: \\s does not detect unicode whitespaces.
-	// So we use fieldsASCII instead of strings.Fields in parsePSOutput.
-	// See https://github.com/docker/docker/pull/24358
-	//nolint: gosimple
-	re := regexp.MustCompile("\\s+([^\\s]*)=\\s*(PID[^\\s]*)")
-	for _, group := range re.FindAllStringSubmatch(psArgs, -1) {
+	for _, group := range psArgsRegexp.FindAllStringSubmatch(psArgs, -1) {
 		if len(group) >= 3 {
 			k := group[1]
 			v := group[2]