package tar

import (
	"io/fs"
	"os/user"
	"runtime"
	"strconv"
	"sync"
	"syscall"
)

func init() {
	sysStat = statUnix
}

// userMap and groupMap caches UID and GID lookups for performance reasons.
// The downside is that renaming uname or gname by the OS never takes effect.
var userMap, groupMap sync.Map // map[int]string

func statUnix(fi fs.FileInfo, h *Header, doNameLookups bool) error {

	cli.BoolFlag{
		Name:   "compat",
		Usage:  "enable strict S3 compatibility by turning off certain performance optimizations",
		Hidden: true,
	},
	// This flag is hidden and to be used only during certain performance testing.
	cli.BoolFlag{
		Name:   "no-compat",
		Usage:  "disable strict S3 compatibility by turning on certain performance optimizations",
		Hidden: true,
	},
}

// Help template for minio.

//     system.xml. Vendors can work with Veeam Product Management and the Alliances team on getting approval to integrate
//     specific system recommendations based on current support case statistics and storage performance possibilities.
//     Vendors might change the settings based on the configuration and scale out of the solution (more storage nodes =>
//     higher task limit).
//
//     <S3ConcurrentTaskLimit>
//

		if r != utf8.RuneError {
			// r is 2 to 4 bytes
			if len(chars) == width {
				if chars == string(r) {
					return i
				}
				continue
			}
			// Use bytealg.IndexString for performance if available.
			if bytealg.MaxLen >= width {
				if bytealg.IndexString(chars, string(r)) >= 0 {
					return i
				}
				continue
			}
		}
		for _, ch := range chars {
			if r == ch {

	if oldLinux() {
		warnings = append(warnings, color.YellowBold("- Detected Linux kernel version older than 4.0.0 release, there are some known potential performance problems with this kernel version. MinIO recommends a minimum of 4.x.x linux kernel version for best performance"))
	}

	maxProcs := runtime.GOMAXPROCS(0)
	cpuProcs := runtime.NumCPU()
	if maxProcs < cpuProcs {

			85, 120, 0, 0, // tag 30805 size 0
		},
	}
	testValidHeader(&h, t)
}

// Just benchmarking how fast the Zip64 test above is. Not related to
// our zip performance, since the test above disabled CRC32 and flate.
func BenchmarkZip64Test(b *testing.B) {
	for i := 0; i < b.N; i++ {
		testZip64(b, 1<<26)
	}
}

func BenchmarkZip64TestSizes(b *testing.B) {

		if err != nil {
			return cfg, err
		}
		if inlineBlock > 128*humanize.KiByte {
			configLogOnceIf(context.Background(), fmt.Errorf("inline block value bigger than recommended max of 128KiB -> %s, performance may degrade for PUT please benchmark the changes", inlineBlockStr), inlineBlockStr)
		}
		cfg.inlineBlock = int64(inlineBlock)
	} else {
		cfg.inlineBlock = 128 * humanize.KiByte
	}

	cfg.initialized = true

			return nil, fmt.Errorf("%w: %+v", ErrUnsupportedDataType, dest)
		}
		return nil, fmt.Errorf("%w: %s.%s", ErrUnsupportedDataType, modelType.PkgPath(), modelType.Name())
	}

	// Cache the Schema for performance,
	// Use the modelType or modelType + schemaTable (if it present) as cache key.
	var schemaCacheKey interface{}
	if specialTableName != "" {
		schemaCacheKey = fmt.Sprintf("%p-%s", modelType, specialTableName)

		idx      = strings.Index(str, ",")
		settings = ParseTagSetting(str, ",")
	)

	// optimize match english letters and midline
	// The following code is basically called in for.
	// In order to avoid the performance problems caused by repeated compilation of regular expressions,
	// it only needs to be done once outside, so optimization is done here.
	if idx != -1 && regEnLetterAndMidline.MatchString(str[0:idx]) {
		name = str[0:idx]

		// We save a lot of calls over the network.
		//
		// This happens repeatedly for all objects that are created concurrently() avoiding this
		// as a List() call is an important performance improvement.
		//
		// Spark based s3a committers are a  big enough use-case to have this optimization.
		//
		// A sample code to see the improvements is as follows, this sample code is