authfs.RootDir: implement Dir interfacemockup

1 files changed, 112 insertions, 0 deletions

diff --git a/back/cmd/authfs/rootdir.go b/back/cmd/authfs/rootdir.go
new file mode 100644
index 0000000..870a5a8
--- /dev/null
+++ b/back/cmd/authfs/rootdir.go
@@ -0,0 +1,112 @@
+package main
+
+import (
+	"bytes"
+
+	p9 "github.com/Harvey-OS/ninep/protocol"
+
+	"git.samanthony.xyz/buth/back/qver"
+)
+
+type RootDir struct {
+	*qver.Version
+	*UsersDir
+	*SessionsDir
+}
+
+func NewRootDir(path string) (*RootDir, error) {
+	ver := qver.New()
+	users, err := NewUsersDir(path, ver)
+	if err != nil {
+		ver.Close()
+		return nil, err
+	}
+	sessions := NewSessionsDir(ver)
+	return &RootDir{ver, users, sessions}, nil
+}
+
+func (r *RootDir) Close() {
+	r.Version.Close()
+	r.UsersDir.Close()
+	r.SessionsDir.Close()
+}
+
+func (r *RootDir) Qid() (p9.QID, error) {
+	ver, err := r.Version.Get()
+	if err != nil {
+		return p9.QID{}, err
+	}
+	return p9.QID{
+		Type:    p9.QTDIR,
+		Version: ver,
+		Path:    rootQidPath,
+	}, nil
+}
+
+func (r *RootDir) Stat() (p9.Dir, error) {
+	qid, err := r.Qid()
+	if err != nil {
+		return p9.Dir{}, err
+	}
+	return p9.Dir{
+		QID:  qid,
+		Mode: p9.DMDIR | p9.DMREAD,
+		// TODO: atime, mtime
+		Name: "/",
+	}, nil
+}
+
+func (r *RootDir) Remove() error { return ErrPerm }
+
+func (r *RootDir) Open(mode p9.Mode) error {
+	if mode != p9.OREAD {
+		return ErrPerm
+	}
+	return nil
+}
+
+func (r *RootDir) Read(off p9.Offset, n p9.Count) ([]byte, error) {
+	userInfo, err := r.UsersDir.Stat()
+	if err != nil {
+		return nil, err
+	}
+	sessInfo, err := r.SessionsDir.Stat()
+	if err != nil {
+		return nil, err
+	}
+
+	buf := new(bytes.Buffer)
+	p9.Marshaldir(buf, userInfo)
+	p9.Marshaldir(buf, sessInfo)
+
+	b := buf.Bytes()
+	lenb := uint64(len(b))
+	lo := clamp(uint64(off), 0, lenb)
+	hi := clamp(lo+uint64(n), 0, lenb)
+	return b[lo:hi], nil
+}
+
+func (r *RootDir) Write(off p9.Offset, b []byte) (p9.Count, error) { return 0, ErrPerm }
+
+func (r *RootDir) Create(name string, perm p9.Perm, mode p9.Mode) (File, error) { return nil, ErrPerm }
+
+func (r *RootDir) Walk(name string) (File, error) {
+	switch name {
+	case "users":
+		return r.UsersDir, nil
+	case "sessions":
+		return r.SessionsDir, nil
+	default:
+		return nil, ErrFileNotExist
+	}
+}
+
+func clamp(x, min, max uint64) uint64 {
+	if x < min {
+		x = min
+	}
+	if x > max {
+		x = max
+	}
+	return x
+}