tstor/pkg/go-nfs/nfs_onlookup.go
2024-03-28 16:09:42 +03:00

86 lines
2.3 KiB
Go

package nfs
import (
"bytes"
"context"
"os"
"github.com/willscott/go-nfs-client/nfs/xdr"
)
func lookupSuccessResponse(ctx context.Context, handle []byte, entPath, dirPath []string, fs Filesystem) ([]byte, error) {
writer := bytes.NewBuffer([]byte{})
if err := xdr.Write(writer, uint32(NFSStatusOk)); err != nil {
return nil, err
}
if err := xdr.Write(writer, handle); err != nil {
return nil, err
}
if err := WritePostOpAttrs(writer, tryStat(ctx, fs, entPath)); err != nil {
return nil, err
}
if err := WritePostOpAttrs(writer, tryStat(ctx, fs, dirPath)); err != nil {
return nil, err
}
return writer.Bytes(), nil
}
func onLookup(ctx context.Context, w *response, userHandle Handler) error {
w.errorFmt = opAttrErrorFormatter
obj := DirOpArg{}
err := xdr.Read(w.req.Body, &obj)
if err != nil {
return &NFSStatusError{NFSStatusInval, err}
}
fs, p, err := userHandle.FromHandle(obj.Handle)
if err != nil {
return &NFSStatusError{NFSStatusStale, err}
}
dirInfo, err := fs.Lstat(ctx, fs.Join(p...))
if err != nil || !dirInfo.IsDir() {
return &NFSStatusError{NFSStatusNotDir, err}
}
// Special cases for "." and ".."
if bytes.Equal(obj.Filename, []byte(".")) {
resp, err := lookupSuccessResponse(ctx, obj.Handle, p, p, fs)
if err != nil {
return &NFSStatusError{NFSStatusServerFault, err}
}
if err := w.Write(resp); err != nil {
return &NFSStatusError{NFSStatusServerFault, err}
}
return nil
}
if bytes.Equal(obj.Filename, []byte("..")) {
if len(p) == 0 {
return &NFSStatusError{NFSStatusAccess, os.ErrPermission}
}
pPath := p[0 : len(p)-1]
pHandle := userHandle.ToHandle(fs, pPath)
resp, err := lookupSuccessResponse(ctx, pHandle, pPath, p, fs)
if err != nil {
return &NFSStatusError{NFSStatusServerFault, err}
}
if err := w.Write(resp); err != nil {
return &NFSStatusError{NFSStatusServerFault, err}
}
return nil
}
reqPath := append(p, string(obj.Filename))
if _, err = fs.Lstat(ctx, fs.Join(reqPath...)); err != nil {
return &NFSStatusError{NFSStatusNoEnt, os.ErrNotExist}
}
newHandle := userHandle.ToHandle(fs, reqPath)
resp, err := lookupSuccessResponse(ctx, newHandle, reqPath, p, fs)
if err != nil {
return &NFSStatusError{NFSStatusServerFault, err}
}
if err := w.Write(resp); err != nil {
return &NFSStatusError{NFSStatusServerFault, err}
}
return nil
}