more specification polishing, document specification points better
diff --git a/request-example.go b/request-example.go
index 7ef4a60..0afaefb 100644
--- a/request-example.go
+++ b/request-example.go
@@ -58,29 +58,24 @@
return fs.openfile(r.Filepath, r.Flags)
}
-func (fs *root) newfile(pathname string) (*memFile, error) {
+func (fs *root) putfile(pathname string, file *memFile) error {
pathname, err := fs.canonName(pathname)
if err != nil {
- return nil, err
+ return err
}
- switch pathname {
- case "", "/":
- // sanity check protection.
- return nil, os.ErrInvalid
+ if !strings.HasPrefix(pathname, "/") {
+ return os.ErrInvalid
}
- if fs.files[pathname] != nil {
- return nil, os.ErrExist
+ if _, err := fs.lfetch(pathname); err != os.ErrNotExist {
+ return os.ErrExist
}
- file := &memFile{
- name: pathname,
- modtime: time.Now(),
- }
+ file.name = pathname
fs.files[pathname] = file
- return file, nil
+ return nil
}
func (fs *root) openfile(pathname string, flags uint32) (*memFile, error) {
@@ -96,6 +91,7 @@
link, err := fs.lfetch(pathname)
for err == nil && link.symlink != "" {
if pflags.Excl {
+ // unless you also passed in O_EXCL
return nil, os.ErrInvalid
}
@@ -103,7 +99,15 @@
link, err = fs.lfetch(pathname)
}
- return fs.newfile(pathname)
+ file := &memFile{
+ modtime: time.Now(),
+ }
+
+ if err := fs.putfile(pathname, file); err != nil {
+ return nil, err
+ }
+
+ return file, nil
}
if err != nil {
@@ -150,15 +154,10 @@
return nil
case "Rename":
- // SSH SPEC: "It is an error if there already exists a file with the name specified by newpath."
- // This varies from the POSIX specification, that says it should replace the new file.
+ // SFTP-v2: "It is an error if there already exists a file with the name specified by newpath."
+ // This varies from the POSIX specification, which allows limited replacement of target files.
if fs.exists(r.Target) {
- return &os.LinkError{
- Op: "rename",
- Old: r.Filepath,
- New: r.Target,
- Err: os.ErrExist,
- }
+ return os.ErrExist
}
return fs.rename(r.Filepath, r.Target)
@@ -167,7 +166,9 @@
return fs.rmdir(r.Filepath)
case "Remove":
- return fs.remove(r.Filepath)
+ // IEEE 1003.1 remove explicitly can unlink files and remove empty directories.
+ // We use instead here the semantics of unlink, which is allowed to be restricted against directories.
+ return fs.unlink(r.Filepath)
case "Mkdir":
return fs.mkdir(r.Filepath)
@@ -194,10 +195,38 @@
return err
}
+ if !strings.HasPrefix(newpath, "/") {
+ return os.ErrInvalid
+ }
+
+ target, err := fs.lfetch(newpath)
+ if err != os.ErrNotExist {
+ if target == file {
+ // IEEE 1003.1: if oldpath and newpath are the same directory entry,
+ // then return no error, and perform no further action.
+ return nil
+ }
+
+ switch {
+ case file.IsDir():
+ // IEEE 1003.1: if oldpath is a directory, and newpath exists,
+ // then newpath must be a directory, and empty.
+ // It is to be removed prior to rename.
+ if err := fs.rmdir(newpath); err != nil {
+ return err
+ }
+
+ case target.IsDir():
+ // IEEE 1003.1: if oldpath is not a directory, and newpath exists,
+ // then newpath may not be a directory.
+ return syscall.EISDIR
+ }
+ }
+
fs.files[newpath] = file
- if dir := file; dir.IsDir() {
- dirprefix := dir.name + "/"
+ if file.IsDir() {
+ dirprefix := file.name + "/"
for name, file := range fs.files {
if strings.HasPrefix(name, dirprefix) {
@@ -229,18 +258,16 @@
}
func (fs *root) mkdir(pathname string) error {
- dir, err := fs.newfile(pathname)
- if err != nil {
- return err
+ dir := &memFile{
+ modtime: time.Now(),
+ isdir: true,
}
- dir.isdir = true
-
- return nil
+ return fs.putfile(pathname, dir)
}
func (fs *root) rmdir(pathname string) error {
- // does not follow symlinks!
+ // IEEE 1003.1: If pathname is a symlink, then rmdir should fail with ENOTDIR.
dir, err := fs.lfetch(pathname)
if err != nil {
return err
@@ -256,11 +283,7 @@
for name := range fs.files {
if path.Dir(name) == pathname {
- return &os.PathError{
- Op: "rmdir",
- Path: pathname + "/",
- Err: errors.New("directory is not empty"),
- }
+ return errors.New("directory not empty")
}
}
@@ -279,30 +302,21 @@
return errors.New("hard link not allowed for directory")
}
- fs.files[newpath] = file
-
- return nil
+ return fs.putfile(newpath, file)
}
// symlink() creates a symbolic link named `linkpath` which contains the string `target`.
// NOTE! This would be called with `symlink(req.Filepath, req.Target)` due to different semantics.
func (fs *root) symlink(target, linkpath string) error {
- _, err := fs.lfetch(linkpath)
- if err != os.ErrNotExist {
- return os.ErrExist
+ link := &memFile{
+ modtime: time.Now(),
+ symlink: target,
}
- link, err := fs.newfile(linkpath)
- if err != nil {
- return err
- }
-
- link.symlink = target
-
- return nil
+ return fs.putfile(linkpath, link)
}
-func (fs *root) remove(pathname string) error {
+func (fs *root) unlink(pathname string) error {
// does not follow symlinks!
file, err := fs.lfetch(pathname)
if err != nil {
@@ -310,6 +324,8 @@
}
if file.IsDir() {
+ // IEEE 1003.1: implementations may opt out of allowing the unlinking of directories.
+ // SFTP-v2: SSH_FXP_REMOVE may not remove directories.
return os.ErrInvalid
}
@@ -365,7 +381,7 @@
return nil, err
}
- // SSH SPEC: The server will respond with a SSH_FXP_NAME packet containing only
+ // SFTP-v2: The server will respond with a SSH_FXP_NAME packet containing only
// one name and a dummy attributes value.
return listerat{
&memFile{
