--- /dev/null
+// Copyright © 2014 Steve Francia <spf@spf13.com>.
+//
+// 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 afero
+
+import (
+ "fmt"
+ "log"
+ "os"
+ "path/filepath"
+ "strings"
+ "sync"
+ "time"
+
+ "github.com/spf13/afero/mem"
+)
+
+type MemMapFs struct {
+ mu sync.RWMutex
+ data map[string]*mem.FileData
+ init sync.Once
+}
+
+func NewMemMapFs() Fs {
+ return &MemMapFs{}
+}
+
+func (m *MemMapFs) getData() map[string]*mem.FileData {
+ m.init.Do(func() {
+ m.data = make(map[string]*mem.FileData)
+ // Root should always exist, right?
+ // TODO: what about windows?
+ m.data[FilePathSeparator] = mem.CreateDir(FilePathSeparator)
+ })
+ return m.data
+}
+
+func (*MemMapFs) Name() string { return "MemMapFS" }
+
+func (m *MemMapFs) Create(name string) (File, error) {
+ name = normalizePath(name)
+ m.mu.Lock()
+ file := mem.CreateFile(name)
+ m.getData()[name] = file
+ m.registerWithParent(file)
+ m.mu.Unlock()
+ return mem.NewFileHandle(file), nil
+}
+
+func (m *MemMapFs) unRegisterWithParent(fileName string) error {
+ f, err := m.lockfreeOpen(fileName)
+ if err != nil {
+ return err
+ }
+ parent := m.findParent(f)
+ if parent == nil {
+ log.Panic("parent of ", f.Name(), " is nil")
+ }
+
+ parent.Lock()
+ mem.RemoveFromMemDir(parent, f)
+ parent.Unlock()
+ return nil
+}
+
+func (m *MemMapFs) findParent(f *mem.FileData) *mem.FileData {
+ pdir, _ := filepath.Split(f.Name())
+ pdir = filepath.Clean(pdir)
+ pfile, err := m.lockfreeOpen(pdir)
+ if err != nil {
+ return nil
+ }
+ return pfile
+}
+
+func (m *MemMapFs) registerWithParent(f *mem.FileData) {
+ if f == nil {
+ return
+ }
+ parent := m.findParent(f)
+ if parent == nil {
+ pdir := filepath.Dir(filepath.Clean(f.Name()))
+ err := m.lockfreeMkdir(pdir, 0777)
+ if err != nil {
+ //log.Println("Mkdir error:", err)
+ return
+ }
+ parent, err = m.lockfreeOpen(pdir)
+ if err != nil {
+ //log.Println("Open after Mkdir error:", err)
+ return
+ }
+ }
+
+ parent.Lock()
+ mem.InitializeDir(parent)
+ mem.AddToMemDir(parent, f)
+ parent.Unlock()
+}
+
+func (m *MemMapFs) lockfreeMkdir(name string, perm os.FileMode) error {
+ name = normalizePath(name)
+ x, ok := m.getData()[name]
+ if ok {
+ // Only return ErrFileExists if it's a file, not a directory.
+ i := mem.FileInfo{FileData: x}
+ if !i.IsDir() {
+ return ErrFileExists
+ }
+ } else {
+ item := mem.CreateDir(name)
+ m.getData()[name] = item
+ m.registerWithParent(item)
+ }
+ return nil
+}
+
+func (m *MemMapFs) Mkdir(name string, perm os.FileMode) error {
+ name = normalizePath(name)
+
+ m.mu.RLock()
+ _, ok := m.getData()[name]
+ m.mu.RUnlock()
+ if ok {
+ return &os.PathError{Op: "mkdir", Path: name, Err: ErrFileExists}
+ }
+
+ m.mu.Lock()
+ item := mem.CreateDir(name)
+ m.getData()[name] = item
+ m.registerWithParent(item)
+ m.mu.Unlock()
+
+ m.Chmod(name, perm|os.ModeDir)
+
+ return nil
+}
+
+func (m *MemMapFs) MkdirAll(path string, perm os.FileMode) error {
+ err := m.Mkdir(path, perm)
+ if err != nil {
+ if err.(*os.PathError).Err == ErrFileExists {
+ return nil
+ }
+ return err
+ }
+ return nil
+}
+
+// Handle some relative paths
+func normalizePath(path string) string {
+ path = filepath.Clean(path)
+
+ switch path {
+ case ".":
+ return FilePathSeparator
+ case "..":
+ return FilePathSeparator
+ default:
+ return path
+ }
+}
+
+func (m *MemMapFs) Open(name string) (File, error) {
+ f, err := m.open(name)
+ if f != nil {
+ return mem.NewReadOnlyFileHandle(f), err
+ }
+ return nil, err
+}
+
+func (m *MemMapFs) openWrite(name string) (File, error) {
+ f, err := m.open(name)
+ if f != nil {
+ return mem.NewFileHandle(f), err
+ }
+ return nil, err
+}
+
+func (m *MemMapFs) open(name string) (*mem.FileData, error) {
+ name = normalizePath(name)
+
+ m.mu.RLock()
+ f, ok := m.getData()[name]
+ m.mu.RUnlock()
+ if !ok {
+ return nil, &os.PathError{Op: "open", Path: name, Err: ErrFileNotFound}
+ }
+ return f, nil
+}
+
+func (m *MemMapFs) lockfreeOpen(name string) (*mem.FileData, error) {
+ name = normalizePath(name)
+ f, ok := m.getData()[name]
+ if ok {
+ return f, nil
+ } else {
+ return nil, ErrFileNotFound
+ }
+}
+
+func (m *MemMapFs) OpenFile(name string, flag int, perm os.FileMode) (File, error) {
+ chmod := false
+ file, err := m.openWrite(name)
+ if os.IsNotExist(err) && (flag&os.O_CREATE > 0) {
+ file, err = m.Create(name)
+ chmod = true
+ }
+ if err != nil {
+ return nil, err
+ }
+ if flag == os.O_RDONLY {
+ file = mem.NewReadOnlyFileHandle(file.(*mem.File).Data())
+ }
+ if flag&os.O_APPEND > 0 {
+ _, err = file.Seek(0, os.SEEK_END)
+ if err != nil {
+ file.Close()
+ return nil, err
+ }
+ }
+ if flag&os.O_TRUNC > 0 && flag&(os.O_RDWR|os.O_WRONLY) > 0 {
+ err = file.Truncate(0)
+ if err != nil {
+ file.Close()
+ return nil, err
+ }
+ }
+ if chmod {
+ m.Chmod(name, perm)
+ }
+ return file, nil
+}
+
+func (m *MemMapFs) Remove(name string) error {
+ name = normalizePath(name)
+
+ m.mu.Lock()
+ defer m.mu.Unlock()
+
+ if _, ok := m.getData()[name]; ok {
+ err := m.unRegisterWithParent(name)
+ if err != nil {
+ return &os.PathError{Op: "remove", Path: name, Err: err}
+ }
+ delete(m.getData(), name)
+ } else {
+ return &os.PathError{Op: "remove", Path: name, Err: os.ErrNotExist}
+ }
+ return nil
+}
+
+func (m *MemMapFs) RemoveAll(path string) error {
+ path = normalizePath(path)
+ m.mu.Lock()
+ m.unRegisterWithParent(path)
+ m.mu.Unlock()
+
+ m.mu.RLock()
+ defer m.mu.RUnlock()
+
+ for p, _ := range m.getData() {
+ if strings.HasPrefix(p, path) {
+ m.mu.RUnlock()
+ m.mu.Lock()
+ delete(m.getData(), p)
+ m.mu.Unlock()
+ m.mu.RLock()
+ }
+ }
+ return nil
+}
+
+func (m *MemMapFs) Rename(oldname, newname string) error {
+ oldname = normalizePath(oldname)
+ newname = normalizePath(newname)
+
+ if oldname == newname {
+ return nil
+ }
+
+ m.mu.RLock()
+ defer m.mu.RUnlock()
+ if _, ok := m.getData()[oldname]; ok {
+ m.mu.RUnlock()
+ m.mu.Lock()
+ m.unRegisterWithParent(oldname)
+ fileData := m.getData()[oldname]
+ delete(m.getData(), oldname)
+ mem.ChangeFileName(fileData, newname)
+ m.getData()[newname] = fileData
+ m.registerWithParent(fileData)
+ m.mu.Unlock()
+ m.mu.RLock()
+ } else {
+ return &os.PathError{Op: "rename", Path: oldname, Err: ErrFileNotFound}
+ }
+ return nil
+}
+
+func (m *MemMapFs) Stat(name string) (os.FileInfo, error) {
+ f, err := m.Open(name)
+ if err != nil {
+ return nil, err
+ }
+ fi := mem.GetFileInfo(f.(*mem.File).Data())
+ return fi, nil
+}
+
+func (m *MemMapFs) Chmod(name string, mode os.FileMode) error {
+ name = normalizePath(name)
+
+ m.mu.RLock()
+ f, ok := m.getData()[name]
+ m.mu.RUnlock()
+ if !ok {
+ return &os.PathError{Op: "chmod", Path: name, Err: ErrFileNotFound}
+ }
+
+ m.mu.Lock()
+ mem.SetMode(f, mode)
+ m.mu.Unlock()
+
+ return nil
+}
+
+func (m *MemMapFs) Chtimes(name string, atime time.Time, mtime time.Time) error {
+ name = normalizePath(name)
+
+ m.mu.RLock()
+ f, ok := m.getData()[name]
+ m.mu.RUnlock()
+ if !ok {
+ return &os.PathError{Op: "chtimes", Path: name, Err: ErrFileNotFound}
+ }
+
+ m.mu.Lock()
+ mem.SetModTime(f, mtime)
+ m.mu.Unlock()
+
+ return nil
+}
+
+func (m *MemMapFs) List() {
+ for _, x := range m.data {
+ y := mem.FileInfo{FileData: x}
+ fmt.Println(x.Name(), y.Size())
+ }
+}
+
+// func debugMemMapList(fs Fs) {
+// if x, ok := fs.(*MemMapFs); ok {
+// x.List()
+// }
+// }
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