go.mod: github.com/opencontainers/runc v1.1.0

Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>

vendor/github.com/opencontainers/selinux/pkg/pwalk/README.md

@@ -8,6 +8,12 @@ By default, it utilizes 2\*runtime.NumCPU() goroutines for callbacks.
 This can be changed by using WalkN function which has the additional
 parameter, specifying the number of goroutines (concurrency).
 
+### pwalk vs pwalkdir
+
+This package is deprecated in favor of
+[pwalkdir](https://pkg.go.dev/github.com/opencontainers/selinux/pkg/pwalkdir),
+which is faster, but requires at least Go 1.16.
+
 ### Caveats
 
 Please note the following limitations of this code:

vendor/github.com/opencontainers/selinux/pkg/pwalk/pwalk.go

@@ -1,12 +1,11 @@
 package pwalk
 
 import (
+	"fmt"
 	"os"
 	"path/filepath"
 	"runtime"
 	"sync"
-
-	"github.com/pkg/errors"
 )
 
 type WalkFunc = filepath.WalkFunc
@@ -20,7 +19,7 @@ type WalkFunc = filepath.WalkFunc
 //
 // Note that this implementation only supports primitive error handling:
 //
-// - no errors are ever passed to WalkFn;
+// - no errors are ever passed to walkFn;
 //
 // - once a walkFn returns any error, all further processing stops
 // and the error is returned to the caller of Walk;
@@ -42,7 +41,7 @@ func Walk(root string, walkFn WalkFunc) error {
 func WalkN(root string, walkFn WalkFunc, num int) error {
 	// make sure limit is sensible
 	if num < 1 {
-		return errors.Errorf("walk(%q): num must be > 0", root)
+		return fmt.Errorf("walk(%q): num must be > 0", root)
 	}
 
 	files := make(chan *walkArgs, 2*num)
@@ -52,6 +51,9 @@ func WalkN(root string, walkFn WalkFunc, num int) error {
 	var (
 		err error
 		wg  sync.WaitGroup
+
+		rootLen   = len(root)
+		rootEntry *walkArgs
 	)
 	wg.Add(1)
 	go func() {
@@ -60,6 +62,11 @@ func WalkN(root string, walkFn WalkFunc, num int) error {
 				close(files)
 				return err
 			}
+			if len(p) == rootLen {
+				// Root entry is processed separately below.
+				rootEntry = &walkArgs{path: p, info: &info}
+				return nil
+			}
 			// add a file to the queue unless a callback sent an error
 			select {
 			case e := <-errCh:
@@ -93,10 +100,14 @@ func WalkN(root string, walkFn WalkFunc, num int) error {
 
 	wg.Wait()
 
+	if err == nil {
+		err = walkFn(rootEntry.path, *rootEntry.info, nil)
+	}
+
 	return err
 }
 
-// walkArgs holds the arguments that were passed to the Walk or WalkLimit
+// walkArgs holds the arguments that were passed to the Walk or WalkN
 // functions.
 type walkArgs struct {
 	path string

vendor/github.com/opencontainers/selinux/pkg/pwalkdir/README.md

@@ -0,0 +1,54 @@
+## pwalkdir: parallel implementation of filepath.WalkDir
+
+This is a wrapper for [filepath.WalkDir](https://pkg.go.dev/path/filepath#WalkDir)
+which may speed it up by calling multiple callback functions (WalkDirFunc)
+in parallel, utilizing goroutines.
+
+By default, it utilizes 2\*runtime.NumCPU() goroutines for callbacks.
+This can be changed by using WalkN function which has the additional
+parameter, specifying the number of goroutines (concurrency).
+
+### pwalk vs pwalkdir
+
+This package is very similar to
+[pwalk](https://pkg.go.dev/github.com/opencontainers/selinux/pkg/pwalkdir),
+but utilizes `filepath.WalkDir` (added to Go 1.16), which does not call stat(2)
+on every entry and is therefore faster (up to 3x, depending on usage scenario).
+
+Users who are OK with requiring Go 1.16+ should switch to this
+implementation.
+
+### Caveats
+
+Please note the following limitations of this code:
+
+* Unlike filepath.WalkDir, the order of calls is non-deterministic;
+
+* Only primitive error handling is supported:
+
+  * fs.SkipDir is not supported;
+
+  * no errors are ever passed to WalkDirFunc;
+
+  * once any error is returned from any walkDirFunc instance, no more calls
+    to WalkDirFunc are made, and the error is returned to the caller of WalkDir;
+
+  * if more than one WalkDirFunc instance will return an error, only one
+    of such errors will be propagated to and returned by WalkDir, others
+    will be silently discarded.
+
+### Documentation
+
+For the official documentation, see
+https://pkg.go.dev/github.com/opencontainers/selinux/pkg/pwalkdir
+
+### Benchmarks
+
+For a WalkDirFunc that consists solely of the return statement, this
+implementation is about 15% slower than the standard library's
+filepath.WalkDir.
+
+Otherwise (if a WalkDirFunc is actually doing something) this is usually
+faster, except when the WalkDirN(..., 1) is used. Run `go test -bench .`
+to see how different operations can benefit from it, as well as how the
+level of paralellism affects the speed.

vendor/github.com/opencontainers/selinux/pkg/pwalkdir/pwalkdir.go

@@ -0,0 +1,116 @@
+//go:build go1.16
+// +build go1.16
+
+package pwalkdir
+
+import (
+	"fmt"
+	"io/fs"
+	"path/filepath"
+	"runtime"
+	"sync"
+)
+
+// Walk is a wrapper for filepath.WalkDir which can call multiple walkFn
+// in parallel, allowing to handle each item concurrently. A maximum of
+// twice the runtime.NumCPU() walkFn will be called at any one time.
+// If you want to change the maximum, use WalkN instead.
+//
+// The order of calls is non-deterministic.
+//
+// Note that this implementation only supports primitive error handling:
+//
+// - no errors are ever passed to walkFn;
+//
+// - once a walkFn returns any error, all further processing stops
+// and the error is returned to the caller of Walk;
+//
+// - filepath.SkipDir is not supported;
+//
+// - if more than one walkFn instance will return an error, only one
+// of such errors will be propagated and returned by Walk, others
+// will be silently discarded.
+func Walk(root string, walkFn fs.WalkDirFunc) error {
+	return WalkN(root, walkFn, runtime.NumCPU()*2)
+}
+
+// WalkN is a wrapper for filepath.WalkDir which can call multiple walkFn
+// in parallel, allowing to handle each item concurrently. A maximum of
+// num walkFn will be called at any one time.
+//
+// Please see Walk documentation for caveats of using this function.
+func WalkN(root string, walkFn fs.WalkDirFunc, num int) error {
+	// make sure limit is sensible
+	if num < 1 {
+		return fmt.Errorf("walk(%q): num must be > 0", root)
+	}
+
+	files := make(chan *walkArgs, 2*num)
+	errCh := make(chan error, 1) // Get the first error, ignore others.
+
+	// Start walking a tree asap.
+	var (
+		err error
+		wg  sync.WaitGroup
+
+		rootLen   = len(root)
+		rootEntry *walkArgs
+	)
+	wg.Add(1)
+	go func() {
+		err = filepath.WalkDir(root, func(p string, entry fs.DirEntry, err error) error {
+			if err != nil {
+				close(files)
+				return err
+			}
+			if len(p) == rootLen {
+				// Root entry is processed separately below.
+				rootEntry = &walkArgs{path: p, entry: entry}
+				return nil
+			}
+			// Add a file to the queue unless a callback sent an error.
+			select {
+			case e := <-errCh:
+				close(files)
+				return e
+			default:
+				files <- &walkArgs{path: p, entry: entry}
+				return nil
+			}
+		})
+		if err == nil {
+			close(files)
+		}
+		wg.Done()
+	}()
+
+	wg.Add(num)
+	for i := 0; i < num; i++ {
+		go func() {
+			for file := range files {
+				if e := walkFn(file.path, file.entry, nil); e != nil {
+					select {
+					case errCh <- e: // sent ok
+					default: // buffer full
+					}
+				}
+			}
+			wg.Done()
+		}()
+	}
+
+	wg.Wait()
+
+	if err == nil {
+		err = walkFn(rootEntry.path, rootEntry.entry, nil)
+	}
+
+	return err
+}
+
+// walkArgs holds the arguments that were passed to the Walk or WalkN
+// functions.
+type walkArgs struct {
+	path  string
+	entry fs.DirEntry
+}