pathutil.go - platform/build/kati - Gitiles

 // Copyright 2015 Google Inc. All rights reserved
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //      http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.

 package kati

 import (
 	"errors"
 	"fmt"
 	"os"
 	"os/exec"
 	"path/filepath"
 	"runtime"
 	"sort"
 	"strings"
 	"sync"
 	"time"
 )

 type wildcardCacheT struct {
 	mu sync.Mutex
 	m  map[string][]string
 }

 var wildcardCache = &wildcardCacheT{
 	m: make(map[string][]string),
 }

 func wildcardGlob(pat string) ([]string, error) {
 	// TODO(ukai): use find cache for glob if exists.
 	pattern := filepath.Clean(pat)
 	if pattern != pat {
 		// For some reason, go's Glob normalizes
 		// foo/../bar to bar.
 		i := strings.IndexAny(pattern, "*?[")
 		if i < 0 {
 			// no wildcard. if any files matched with pattern,
 			// return pat.
 			_, err := os.Stat(pat)
 			if err != nil {
 				return nil, nil
 			}
 			return []string{pat}, nil
 		}
 		if strings.Contains(pattern[i+1:], "..") {
 			// We ask shell to expand a glob to avoid this.
 			cmdline := []string{"/bin/sh", "-c", "/bin/ls -d " + pat}
 			cmd := exec.Cmd{
 				Path: cmdline[0],
 				Args: cmdline,
 			}
 			// Ignore errors.
 			out, _ := cmd.Output()
 			ws := newWordScanner(out)
 			var files []string
 			for ws.Scan() {
 				files = append(files, string(ws.Bytes()))
 			}
 			return files, nil
 		}
 		// prefix + meta + suffix, and suffix doesn't have '..'
 		prefix := pattern[:i]
 		i = strings.IndexAny(pat, "*?[")
 		if i < 0 {
 			return nil, fmt.Errorf("wildcard metachar mismatch? pattern=%q pat=%q", pattern, pat)
 		}
 		oprefix := pat[:i]
 		matched, err := filepath.Glob(pattern)
 		if err != nil {
 			return nil, err
 		}
 		var files []string
 		for _, m := range matched {
 			file := oprefix + strings.TrimPrefix(m, prefix)
 			_, err := os.Stat(file)
 			if err != nil {
 				continue
 			}
 			files = append(files, file)
 		}
 		return files, nil
 	}
 	return filepath.Glob(pat)
 }

 func wildcard(sw *ssvWriter, pat string) error {
 	if UseWildcardCache {
 		// TODO(ukai): make sure it didn't chdir?
 		wildcardCache.mu.Lock()
 		files, ok := wildcardCache.m[pat]
 		wildcardCache.mu.Unlock()
 		if ok {
 			for _, file := range files {
 				sw.WriteString(file)
 			}
 			return nil
 		}
 	}
 	files, err := wildcardGlob(pat)
 	if err != nil {
 		return err
 	}
 	for _, file := range files {
 		sw.WriteString(file)
 	}
 	if UseWildcardCache {
 		wildcardCache.mu.Lock()
 		wildcardCache.m[pat] = files
 		wildcardCache.mu.Unlock()
 	}
 	return nil
 }

 type fileInfo struct {
 	path string
 	mode os.FileMode
 }

 type androidFindCacheT struct {
 	once     sync.Once
 	filesch  chan []fileInfo
 	leavesch chan []fileInfo
 	files    []fileInfo
 	leaves   []fileInfo
 	scanTime time.Duration
 }

 var (
 	androidFindCache        androidFindCacheT
 	androidDefaultLeafNames = []string{"CleanSpec.mk", "Android.mk"}
 )

 // AndroidFindCacheInit initializes find cache for android build.
 func AndroidFindCacheInit(prunes, leafNames []string) {
 	if leafNames != nil {
 		androidDefaultLeafNames = leafNames
 	}
 	androidFindCache.init(prunes)
 }

 func (c *androidFindCacheT) ready() bool {
 	if c.files != nil {
 		return true
 	}
 	select {
 	case c.files = <-c.filesch:
 	}
 	return c.files != nil
 }

 func (c *androidFindCacheT) leavesReady() bool {
 	if c.leaves != nil {
 		return true
 	}
 	select {
 	case c.leaves = <-c.leavesch:
 	}
 	return c.leaves != nil
 }

 func (c *androidFindCacheT) init(prunes []string) {
 	c.once.Do(func() {
 		c.filesch = make(chan []fileInfo, 1)
 		c.leavesch = make(chan []fileInfo, 1)
 		go c.start(prunes, androidDefaultLeafNames)
 	})
 }

 func (c *androidFindCacheT) start(prunes, leafNames []string) {
 	logf("find cache init: prunes=%q leafNames=%q", prunes, leafNames)
 	te := traceEvent.begin("findcache", literal("init"), traceEventFindCache)
 	defer func() {
 		traceEvent.end(te)
 		c.scanTime = time.Since(te.t)
 		logStats("android find cache scan: %v", c.scanTime)
 	}()

 	dirs := make(chan string, 32)
 	filech := make(chan fileInfo, 1000)
 	leafch := make(chan fileInfo, 1000)
 	var wg sync.WaitGroup
 	numWorker := runtime.NumCPU() - 1
 	wg.Add(numWorker)
 	for i := 0; i < numWorker; i++ {
 		go func() {
 			defer wg.Done()
 			for dir := range dirs {
 				err := filepath.Walk(dir, func(path string, info os.FileInfo, err error) error {
 					if info.IsDir() {
 						for _, prune := range prunes {
 							if info.Name() == prune {
 								logf("find cache prune: %s", path)
 								return filepath.SkipDir
 							}
 						}
 					}
 					filech <- fileInfo{
 						path: path,
 						mode: info.Mode(),
 					}
 					for _, leaf := range leafNames {
 						if info.Name() == leaf {
 							logf("find cache leaf: %s", path)
 							leafch <- fileInfo{
 								path: path,
 								mode: info.Mode(),
 							}
 							break
 						}
 					}
 					return nil
 				})
 				if err != nil && err != filepath.SkipDir {
 					logf("error in adnroid find cache: %v", err)
 					close(c.filesch)
 					close(c.leavesch)
 					return
 				}
 			}
 		}()
 	}

 	go func() {
 		dirs := make(map[string]bool)
 		leavesTe := traceEvent.begin("findcache", literal("leaves"), traceEventFindCacheLeaves)
 		var leaves []fileInfo
 		nfiles := 0
 		for leaf := range leafch {
 			leaves = append(leaves, leaf)
 			nfiles++
 			for dir := filepath.Dir(leaf.path); dir != "."; dir = filepath.Dir(dir) {
 				if dirs[dir] {
 					break
 				}
 				leaves = append(leaves, fileInfo{
 					path: dir,
 					mode: leaf.mode | os.ModeDir,
 				})
 				dirs[dir] = true
 			}
 		}
 		sort.Sort(fileInfoByLeaf(leaves))
 		c.leavesch <- leaves
 		traceEvent.end(leavesTe)
 		logStats("%d leaves %d dirs in find cache", nfiles, len(dirs))
 		for i, leaf := range leaves {
 			logf("android findleaves cache: %d: %s %v", i, leaf.path, leaf.mode)
 		}
 	}()

 	go func() {
 		filesTe := traceEvent.begin("findcache", literal("files"), traceEventFindCacheFiles)
 		var files []fileInfo
 		for file := range filech {
 			files = append(files, file)
 		}
 		sort.Sort(fileInfoByName(files))
 		c.filesch <- files
 		traceEvent.end(filesTe)
 		logStats("%d files in find cache", len(files))
 		for i, fi := range files {
 			logf("android find cache: %d: %s %v", i, fi.path, fi.mode)
 		}
 	}()

 	curdir, err := os.Open(".")
 	if err != nil {
 		logf("open . failed: %v", err)
 		close(c.filesch)
 		close(c.leavesch)
 		return
 	}
 	names, err := curdir.Readdirnames(-1)
 	if err != nil {
 		logf("readdir . failed: %v", err)
 		close(c.filesch)
 		close(c.leavesch)
 		return
 	}
 	curdir.Close()

 	for _, name := range names {
 		dirs <- name
 	}
 	close(dirs)
 	wg.Wait()
 	close(filech)
 	close(leafch)
 }

 type fileInfoByName []fileInfo

 func (f fileInfoByName) Len() int      { return len(f) }
 func (f fileInfoByName) Swap(i, j int) { f[i], f[j] = f[j], f[i] }
 func (f fileInfoByName) Less(i, j int) bool {
 	return f[i].path < f[j].path
 }

 type fileInfoByLeaf []fileInfo

 func (f fileInfoByLeaf) Len() int      { return len(f) }
 func (f fileInfoByLeaf) Swap(i, j int) { f[i], f[j] = f[j], f[i] }
 func (f fileInfoByLeaf) Less(i, j int) bool {
 	di := strings.Count(f[i].path, "/")
 	dj := strings.Count(f[j].path, "/")
 	if di != dj {
 		return di < dj
 	}
 	diri := filepath.Dir(f[i].path) + "/"
 	dirj := filepath.Dir(f[j].path) + "/"
 	if diri != dirj {
 		return diri < dirj
 	}
 	mdi := f[i].mode & os.ModeDir
 	mdj := f[j].mode & os.ModeDir
 	if mdi != mdj {
 		return mdi < mdj
 	}
 	return f[i].path < f[j].path
 }

 var errSkipDir = errors.New("skip dir")

 func (c *androidFindCacheT) walk(dir string, walkFn func(int, fileInfo) error) error {
 	i := sort.Search(len(c.files), func(i int) bool {
 		return c.files[i].path >= dir
 	})
 	logf("android find in dir cache: %s i=%d/%d", dir, i, len(c.files))
 	start := i
 	var skipdirs []string
 Loop:
 	for i := start; i < len(c.files); i++ {
 		if c.files[i].path == dir {
 			err := walkFn(i, c.files[i])
 			if err != nil {
 				return err
 			}
 			continue
 		}
 		if !strings.HasPrefix(c.files[i].path, dir) {
 			logf("android find in dir cache: %s end=%d/%d", dir, i, len(c.files))
 			return nil
 		}
 		if !strings.HasPrefix(c.files[i].path, dir+"/") {
 			continue
 		}
 		for _, skip := range skipdirs {
 			if strings.HasPrefix(c.files[i].path, skip+"/") {
 				continue Loop
 			}
 		}

 		err := walkFn(i, c.files[i])
 		if err == errSkipDir {
 			logf("android find in skip dir: %s", c.files[i].path)
 			skipdirs = append(skipdirs, c.files[i].path)
 			continue
 		}
 		if err != nil {
 			return err
 		}
 	}
 	return nil
 }

 // pattern in repo/android/build/core/definitions.mk
 // find-subdir-assets
 // if [ -d $1 ] ; then cd $1 ; find ./ -not -name '.*' -and -type f -and -not -type l ; fi
 func (c *androidFindCacheT) findInDir(sw *ssvWriter, dir string) {
 	dir = filepath.Clean(dir)
 	logf("android find in dir cache: %s", dir)
 	c.walk(dir, func(_ int, fi fileInfo) error {
 		// -not -name '.*'
 		if strings.HasPrefix(filepath.Base(fi.path), ".") {
 			return nil
 		}
 		// -type f and -not -type l
 		// regular type and not symlink
 		if !fi.mode.IsRegular() {
 			return nil
 		}
 		name := strings.TrimPrefix(fi.path, dir+"/")
 		name = "./" + name
 		sw.WriteString(name)
 		logf("android find in dir cache: %s=> %s", dir, name)
 		return nil
 	})
 }

 // pattern in repo/android/build/core/definitions.mk
 // all-java-files-under etc
 // cd ${LOCAL_PATH} ; find -L $1 -name "*<ext>" -and -not -name ".*"
 // returns false if symlink is found.
 func (c *androidFindCacheT) findExtFilesUnder(sw *ssvWriter, chdir, root, ext string) bool {
 	chdir = filepath.Clean(chdir)
 	dir := filepath.Join(chdir, root)
 	logf("android find %s in dir cache: %s %s", ext, chdir, root)
 	// check symlinks
 	var matches []int
 	err := c.walk(dir, func(i int, fi fileInfo) error {
 		if fi.mode&os.ModeSymlink == os.ModeSymlink {
 			logf("android find %s in dir cache: detect symlink %s %v", ext, c.files[i].path, c.files[i].mode)
 			return fmt.Errorf("symlink %s", fi.path)
 		}
 		matches = append(matches, i)
 		return nil
 	})
 	if err != nil {
 		return false
 	}
 	// no symlinks
 	for _, i := range matches {
 		fi := c.files[i]
 		base := filepath.Base(fi.path)
 		// -name "*<ext>"
 		if filepath.Ext(base) != ext {
 			continue
 		}
 		// -not -name ".*"
 		if strings.HasPrefix(base, ".") {
 			continue
 		}
 		name := strings.TrimPrefix(fi.path, chdir+"/")
 		sw.WriteString(name)
 		logf("android find %s in dir cache: %s=> %s", ext, dir, name)
 	}
 	return true
 }

 // pattern: in repo/android/build/core/base_rules.mk
 // java_resource_file_groups+= ...
 // cd ${TOP_DIR}${LOCAL_PATH}/${dir} && find . -type d -a -name ".svn" -prune \
 // -o -type f -a \! -name "*.java" -a \! -name "package.html" -a \! \
 // -name "overview.html" -a \! -name ".*.swp" -a \! -name ".DS_Store" \
 // -a \! -name "*~" -print )
 func (c *androidFindCacheT) findJavaResourceFileGroup(sw *ssvWriter, dir string) {
 	logf("android find java resource in dir cache: %s", dir)
 	c.walk(filepath.Clean(dir), func(_ int, fi fileInfo) error {
 		// -type d -a -name ".svn" -prune
 		if fi.mode.IsDir() && filepath.Base(fi.path) == ".svn" {
 			return errSkipDir
 		}
 		// -type f
 		if !fi.mode.IsRegular() {
 			return nil
 		}
 		// ! -name "*.java" -a ! -name "package.html" -a
 		// ! -name "overview.html" -a ! -name ".*.swp" -a
 		// ! -name ".DS_Store" -a ! -name "*~"
 		base := filepath.Base(fi.path)
 		if filepath.Ext(base) == ".java" ||
 			base == "package.html" ||
 			base == "overview.html" ||
 			(strings.HasPrefix(base, ".") && strings.HasSuffix(base, ".swp")) ||
 			base == ".DS_Store" ||
 			strings.HasSuffix(base, "~") {
 			return nil
 		}
 		name := strings.TrimPrefix(fi.path, dir+"/")
 		name = "./" + name
 		sw.WriteString(name)
 		logf("android find java resource in dir cache: %s=> %s", dir, name)
 		return nil
 	})
 }

 func (c *androidFindCacheT) findleaves(sw *ssvWriter, dir, name string, prunes []string, mindepth int) bool {
 	var found []string
 	var dirs []string
 	topdepth := 1 + strings.Count(dir, "/")
 	dirs = append(dirs, dir)
 	for len(dirs) > 0 {
 		dir = filepath.Clean(dirs[0]) + "/"
 		dirs = dirs[1:]
 		if dir == "./" {
 			dir = ""
 		}
 		depth := strings.Count(dir, "/")
 		// logf("android findleaves dir=%q depth=%d dirs=%q", dir, depth, dirs)
 		i := sort.Search(len(c.leaves), func(i int) bool {
 			di := strings.Count(c.leaves[i].path, "/")
 			if di != depth {
 				return di >= depth
 			}
 			diri := filepath.Dir(c.leaves[i].path) + "/"
 			if diri != dir {
 				return diri >= dir
 			}
 			return c.leaves[i].path >= dir
 		})
 		logf("android findleaves dir=%q i=%d/%d", dir, i, len(c.leaves))

 	Scandir:
 		for ; i < len(c.leaves); i++ {
 			if dir == "" && strings.Contains(c.leaves[i].path, "/") {
 				break
 			}
 			if !strings.HasPrefix(c.leaves[i].path, dir) {
 				break
 			}
 			if mindepth < 0 || depth >= topdepth+mindepth {
 				if !c.leaves[i].mode.IsDir() && filepath.Base(c.leaves[i].path) == name {
 					n := "./" + c.leaves[i].path
 					found = append(found, n)
 					logf("android findleaves name=%s=> %s (depth=%d topdepth=%d mindepth=%d)", name, n, depth, topdepth, mindepth)
 					break Scandir
 				}
 			}
 			if c.leaves[i].mode.IsDir() {
 				dirs = append(dirs, c.leaves[i].path)
 			}
 		}
 		// logf("android findleaves next dirs=%q", dirs)
 	}
 	logf("android findleave done")
 	sort.Strings(found)
 	for _, f := range found {
 		sw.WriteString(f)
 	}
 	return true
 }
	// Copyright 2015 Google Inc. All rights reserved
	//
	// Licensed under the Apache License, Version 2.0 (the "License");
	// you may not use this file except in compliance with the License.
	// You may obtain a copy of the License at
	//
	// http://www.apache.org/licenses/LICENSE-2.0
	//
	// Unless required by applicable law or agreed to in writing, software
	// distributed under the License is distributed on an "AS IS" BASIS,
	// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	// See the License for the specific language governing permissions and
	// limitations under the License.

	package kati

	import (
	"errors"
	"fmt"
	"os"
	"os/exec"
	"path/filepath"
	"runtime"
	"sort"
	"strings"
	"sync"
	"time"
	)

	type wildcardCacheT struct {
	mu sync.Mutex
	m map[string][]string
	}

	var wildcardCache = &wildcardCacheT{
	m: make(map[string][]string),
	}

	func wildcardGlob(pat string) ([]string, error) {
	// TODO(ukai): use find cache for glob if exists.
	pattern := filepath.Clean(pat)
	if pattern != pat {
	// For some reason, go's Glob normalizes
	// foo/../bar to bar.
	i := strings.IndexAny(pattern, "*?[")
	if i < 0 {
	// no wildcard. if any files matched with pattern,
	// return pat.
	_, err := os.Stat(pat)
	if err != nil {
	return nil, nil
	}
	return []string{pat}, nil
	}
	if strings.Contains(pattern[i+1:], "..") {
	// We ask shell to expand a glob to avoid this.
	cmdline := []string{"/bin/sh", "-c", "/bin/ls -d " + pat}
	cmd := exec.Cmd{
	Path: cmdline[0],
	Args: cmdline,
	}
	// Ignore errors.
	out, _ := cmd.Output()
	ws := newWordScanner(out)
	var files []string
	for ws.Scan() {
	files = append(files, string(ws.Bytes()))
	}
	return files, nil
	}
	// prefix + meta + suffix, and suffix doesn't have '..'
	prefix := pattern[:i]
	i = strings.IndexAny(pat, "*?[")
	if i < 0 {
	return nil, fmt.Errorf("wildcard metachar mismatch? pattern=%q pat=%q", pattern, pat)
	}
	oprefix := pat[:i]
	matched, err := filepath.Glob(pattern)
	if err != nil {
	return nil, err
	}
	var files []string
	for _, m := range matched {
	file := oprefix + strings.TrimPrefix(m, prefix)
	_, err := os.Stat(file)
	if err != nil {
	continue
	}
	files = append(files, file)
	}
	return files, nil
	}
	return filepath.Glob(pat)
	}

	func wildcard(sw *ssvWriter, pat string) error {
	if UseWildcardCache {
	// TODO(ukai): make sure it didn't chdir?
	wildcardCache.mu.Lock()
	files, ok := wildcardCache.m[pat]
	wildcardCache.mu.Unlock()
	if ok {
	for _, file := range files {
	sw.WriteString(file)
	}
	return nil
	}
	}
	files, err := wildcardGlob(pat)
	if err != nil {
	return err
	}
	for _, file := range files {
	sw.WriteString(file)
	}
	if UseWildcardCache {
	wildcardCache.mu.Lock()
	wildcardCache.m[pat] = files
	wildcardCache.mu.Unlock()
	}
	return nil
	}

	type fileInfo struct {
	path string
	mode os.FileMode
	}

	type androidFindCacheT struct {
	once sync.Once
	filesch chan []fileInfo
	leavesch chan []fileInfo
	files []fileInfo
	leaves []fileInfo
	scanTime time.Duration
	}

	var (
	androidFindCache androidFindCacheT
	androidDefaultLeafNames = []string{"CleanSpec.mk", "Android.mk"}
	)

	// AndroidFindCacheInit initializes find cache for android build.
	func AndroidFindCacheInit(prunes, leafNames []string) {
	if leafNames != nil {
	androidDefaultLeafNames = leafNames
	}
	androidFindCache.init(prunes)
	}

	func (c *androidFindCacheT) ready() bool {
	if c.files != nil {
	return true
	}
	select {
	case c.files = <-c.filesch:
	}
	return c.files != nil
	}

	func (c *androidFindCacheT) leavesReady() bool {
	if c.leaves != nil {
	return true
	}
	select {
	case c.leaves = <-c.leavesch:
	}
	return c.leaves != nil
	}

	func (c *androidFindCacheT) init(prunes []string) {
	c.once.Do(func() {
	c.filesch = make(chan []fileInfo, 1)
	c.leavesch = make(chan []fileInfo, 1)
	go c.start(prunes, androidDefaultLeafNames)
	})
	}

	func (c *androidFindCacheT) start(prunes, leafNames []string) {
	logf("find cache init: prunes=%q leafNames=%q", prunes, leafNames)
	te := traceEvent.begin("findcache", literal("init"), traceEventFindCache)
	defer func() {
	traceEvent.end(te)
	c.scanTime = time.Since(te.t)
	logStats("android find cache scan: %v", c.scanTime)
	}()

	dirs := make(chan string, 32)
	filech := make(chan fileInfo, 1000)
	leafch := make(chan fileInfo, 1000)
	var wg sync.WaitGroup
	numWorker := runtime.NumCPU() - 1
	wg.Add(numWorker)
	for i := 0; i < numWorker; i++ {
	go func() {
	defer wg.Done()
	for dir := range dirs {
	err := filepath.Walk(dir, func(path string, info os.FileInfo, err error) error {
	if info.IsDir() {
	for _, prune := range prunes {
	if info.Name() == prune {
	logf("find cache prune: %s", path)
	return filepath.SkipDir
	}
	}
	}
	filech <- fileInfo{
	path: path,
	mode: info.Mode(),
	}
	for _, leaf := range leafNames {
	if info.Name() == leaf {
	logf("find cache leaf: %s", path)
	leafch <- fileInfo{
	path: path,
	mode: info.Mode(),
	}
	break
	}
	}
	return nil
	})
	if err != nil && err != filepath.SkipDir {
	logf("error in adnroid find cache: %v", err)
	close(c.filesch)
	close(c.leavesch)
	return
	}
	}
	}()
	}

	go func() {
	dirs := make(map[string]bool)
	leavesTe := traceEvent.begin("findcache", literal("leaves"), traceEventFindCacheLeaves)
	var leaves []fileInfo
	nfiles := 0
	for leaf := range leafch {
	leaves = append(leaves, leaf)
	nfiles++
	for dir := filepath.Dir(leaf.path); dir != "."; dir = filepath.Dir(dir) {
	if dirs[dir] {
	break
	}
	leaves = append(leaves, fileInfo{
	path: dir,
	mode: leaf.mode \| os.ModeDir,
	})
	dirs[dir] = true
	}
	}
	sort.Sort(fileInfoByLeaf(leaves))
	c.leavesch <- leaves
	traceEvent.end(leavesTe)
	logStats("%d leaves %d dirs in find cache", nfiles, len(dirs))
	for i, leaf := range leaves {
	logf("android findleaves cache: %d: %s %v", i, leaf.path, leaf.mode)
	}
	}()

	go func() {
	filesTe := traceEvent.begin("findcache", literal("files"), traceEventFindCacheFiles)
	var files []fileInfo
	for file := range filech {
	files = append(files, file)
	}
	sort.Sort(fileInfoByName(files))
	c.filesch <- files
	traceEvent.end(filesTe)
	logStats("%d files in find cache", len(files))
	for i, fi := range files {
	logf("android find cache: %d: %s %v", i, fi.path, fi.mode)
	}
	}()

	curdir, err := os.Open(".")
	if err != nil {
	logf("open . failed: %v", err)
	close(c.filesch)
	close(c.leavesch)
	return
	}
	names, err := curdir.Readdirnames(-1)
	if err != nil {
	logf("readdir . failed: %v", err)
	close(c.filesch)
	close(c.leavesch)
	return
	}
	curdir.Close()

	for _, name := range names {
	dirs <- name
	}
	close(dirs)
	wg.Wait()
	close(filech)
	close(leafch)
	}

	type fileInfoByName []fileInfo

	func (f fileInfoByName) Len() int { return len(f) }
	func (f fileInfoByName) Swap(i, j int) { f[i], f[j] = f[j], f[i] }
	func (f fileInfoByName) Less(i, j int) bool {
	return f[i].path < f[j].path
	}

	type fileInfoByLeaf []fileInfo

	func (f fileInfoByLeaf) Len() int { return len(f) }
	func (f fileInfoByLeaf) Swap(i, j int) { f[i], f[j] = f[j], f[i] }
	func (f fileInfoByLeaf) Less(i, j int) bool {
	di := strings.Count(f[i].path, "/")
	dj := strings.Count(f[j].path, "/")
	if di != dj {
	return di < dj
	}
	diri := filepath.Dir(f[i].path) + "/"
	dirj := filepath.Dir(f[j].path) + "/"
	if diri != dirj {
	return diri < dirj
	}
	mdi := f[i].mode & os.ModeDir
	mdj := f[j].mode & os.ModeDir
	if mdi != mdj {
	return mdi < mdj
	}
	return f[i].path < f[j].path
	}

	var errSkipDir = errors.New("skip dir")

	func (c *androidFindCacheT) walk(dir string, walkFn func(int, fileInfo) error) error {
	i := sort.Search(len(c.files), func(i int) bool {
	return c.files[i].path >= dir
	})
	logf("android find in dir cache: %s i=%d/%d", dir, i, len(c.files))
	start := i
	var skipdirs []string
	Loop:
	for i := start; i < len(c.files); i++ {
	if c.files[i].path == dir {
	err := walkFn(i, c.files[i])
	if err != nil {
	return err
	}
	continue
	}
	if !strings.HasPrefix(c.files[i].path, dir) {
	logf("android find in dir cache: %s end=%d/%d", dir, i, len(c.files))
	return nil
	}
	if !strings.HasPrefix(c.files[i].path, dir+"/") {
	continue
	}
	for _, skip := range skipdirs {
	if strings.HasPrefix(c.files[i].path, skip+"/") {
	continue Loop
	}
	}

	err := walkFn(i, c.files[i])
	if err == errSkipDir {
	logf("android find in skip dir: %s", c.files[i].path)
	skipdirs = append(skipdirs, c.files[i].path)
	continue
	}
	if err != nil {
	return err
	}
	}
	return nil
	}

	// pattern in repo/android/build/core/definitions.mk
	// find-subdir-assets
	// if [ -d $1 ] ; then cd $1 ; find ./ -not -name '.*' -and -type f -and -not -type l ; fi
	func (c androidFindCacheT) findInDir(sw ssvWriter, dir string) {
	dir = filepath.Clean(dir)
	logf("android find in dir cache: %s", dir)
	c.walk(dir, func(_ int, fi fileInfo) error {
	// -not -name '.*'
	if strings.HasPrefix(filepath.Base(fi.path), ".") {
	return nil
	}
	// -type f and -not -type l
	// regular type and not symlink
	if !fi.mode.IsRegular() {
	return nil
	}
	name := strings.TrimPrefix(fi.path, dir+"/")
	name = "./" + name
	sw.WriteString(name)
	logf("android find in dir cache: %s=> %s", dir, name)
	return nil
	})
	}

	// pattern in repo/android/build/core/definitions.mk
	// all-java-files-under etc
	// cd ${LOCAL_PATH} ; find -L $1 -name "<ext>" -and -not -name "."
	// returns false if symlink is found.
	func (c androidFindCacheT) findExtFilesUnder(sw ssvWriter, chdir, root, ext string) bool {
	chdir = filepath.Clean(chdir)
	dir := filepath.Join(chdir, root)
	logf("android find %s in dir cache: %s %s", ext, chdir, root)
	// check symlinks
	var matches []int
	err := c.walk(dir, func(i int, fi fileInfo) error {
	if fi.mode&os.ModeSymlink == os.ModeSymlink {
	logf("android find %s in dir cache: detect symlink %s %v", ext, c.files[i].path, c.files[i].mode)
	return fmt.Errorf("symlink %s", fi.path)
	}
	matches = append(matches, i)
	return nil
	})
	if err != nil {
	return false
	}
	// no symlinks
	for _, i := range matches {
	fi := c.files[i]
	base := filepath.Base(fi.path)
	// -name "*<ext>"
	if filepath.Ext(base) != ext {
	continue
	}
	// -not -name ".*"
	if strings.HasPrefix(base, ".") {
	continue
	}
	name := strings.TrimPrefix(fi.path, chdir+"/")
	sw.WriteString(name)
	logf("android find %s in dir cache: %s=> %s", ext, dir, name)
	}
	return true
	}

	// pattern: in repo/android/build/core/base_rules.mk
	// java_resource_file_groups+= ...
	// cd ${TOP_DIR}${LOCAL_PATH}/${dir} && find . -type d -a -name ".svn" -prune \
	// -o -type f -a \! -name "*.java" -a \! -name "package.html" -a \! \
	// -name "overview.html" -a \! -name ".*.swp" -a \! -name ".DS_Store" \
	// -a \! -name "*~" -print )
	func (c androidFindCacheT) findJavaResourceFileGroup(sw ssvWriter, dir string) {
	logf("android find java resource in dir cache: %s", dir)
	c.walk(filepath.Clean(dir), func(_ int, fi fileInfo) error {
	// -type d -a -name ".svn" -prune
	if fi.mode.IsDir() && filepath.Base(fi.path) == ".svn" {
	return errSkipDir
	}
	// -type f
	if !fi.mode.IsRegular() {
	return nil
	}
	// ! -name "*.java" -a ! -name "package.html" -a
	// ! -name "overview.html" -a ! -name ".*.swp" -a
	// ! -name ".DS_Store" -a ! -name "*~"
	base := filepath.Base(fi.path)
	if filepath.Ext(base) == ".java" \|\|
	base == "package.html" \|\|
	base == "overview.html" \|\|
	(strings.HasPrefix(base, ".") && strings.HasSuffix(base, ".swp")) \|\|
	base == ".DS_Store" \|\|
	strings.HasSuffix(base, "~") {
	return nil
	}
	name := strings.TrimPrefix(fi.path, dir+"/")
	name = "./" + name
	sw.WriteString(name)
	logf("android find java resource in dir cache: %s=> %s", dir, name)
	return nil
	})
	}

	func (c androidFindCacheT) findleaves(sw ssvWriter, dir, name string, prunes []string, mindepth int) bool {
	var found []string
	var dirs []string
	topdepth := 1 + strings.Count(dir, "/")
	dirs = append(dirs, dir)
	for len(dirs) > 0 {
	dir = filepath.Clean(dirs[0]) + "/"
	dirs = dirs[1:]
	if dir == "./" {
	dir = ""
	}
	depth := strings.Count(dir, "/")
	// logf("android findleaves dir=%q depth=%d dirs=%q", dir, depth, dirs)
	i := sort.Search(len(c.leaves), func(i int) bool {
	di := strings.Count(c.leaves[i].path, "/")
	if di != depth {
	return di >= depth
	}
	diri := filepath.Dir(c.leaves[i].path) + "/"
	if diri != dir {
	return diri >= dir
	}
	return c.leaves[i].path >= dir
	})
	logf("android findleaves dir=%q i=%d/%d", dir, i, len(c.leaves))

	Scandir:
	for ; i < len(c.leaves); i++ {
	if dir == "" && strings.Contains(c.leaves[i].path, "/") {
	break
	}
	if !strings.HasPrefix(c.leaves[i].path, dir) {
	break
	}
	if mindepth < 0 \|\| depth >= topdepth+mindepth {
	if !c.leaves[i].mode.IsDir() && filepath.Base(c.leaves[i].path) == name {
	n := "./" + c.leaves[i].path
	found = append(found, n)
	logf("android findleaves name=%s=> %s (depth=%d topdepth=%d mindepth=%d)", name, n, depth, topdepth, mindepth)
	break Scandir
	}
	}
	if c.leaves[i].mode.IsDir() {
	dirs = append(dirs, c.leaves[i].path)
	}
	}
	// logf("android findleaves next dirs=%q", dirs)
	}
	logf("android findleave done")
	sort.Strings(found)
	for _, f := range found {
	sw.WriteString(f)
	}
	return true
	}