func (s *file) CreateTemp(asc bool) (bt temp, err error) {
f, err := s.tempFile("", "ql-tmp-")
if err != nil {
return nil, err
}
fn := f.Name()
filer := lldb.NewOSFiler(f)
a, err := lldb.NewAllocator(filer, &lldb.Options{})
if err != nil {
f.Close()
os.Remove(fn)
return nil, err
}
k := 1
if !asc {
k = -1
}
t, _, err := lldb.CreateBTree(a, func(a, b []byte) int { //TODO w/ error return
da, err := lldb.DecodeScalars(a)
if err != nil {
log.Panic(err)
}
if err = s.expandBytes(da); err != nil {
log.Panic(err)
}
db, err := lldb.DecodeScalars(b)
if err != nil {
log.Panic(err)
}
if err = s.expandBytes(db); err != nil {
log.Panic(err)
}
return k * collate(da, db)
})
if err != nil {
f.Close()
if fn != "" {
os.Remove(fn)
}
return nil, err
}
x := &fileTemp{file: &file{
a: a,
codec: newGobCoder(),
f0: f,
},
t: t}
return x, nil
}
func newFileFromOSFile(f lldb.OSFile) (fi *file, err error) {
nm := lockName(f.Name())
lck, err := lock.Lock(nm)
if err != nil {
if lck != nil {
lck.Close()
}
return nil, err
}
close := true
defer func() {
if close && lck != nil {
lck.Close()
}
}()
var w *os.File
closew := false
wn := walName(f.Name())
w, err = os.OpenFile(wn, os.O_CREATE|os.O_EXCL|os.O_RDWR, 0666)
closew = true
defer func() {
if closew {
nm := w.Name()
w.Close()
os.Remove(nm)
w = nil
}
}()
if err != nil {
if !os.IsExist(err) {
return nil, err
}
closew = false
w, err = os.OpenFile(wn, os.O_RDWR, 0666)
if err != nil {
return nil, err
}
closew = true
st, err := w.Stat()
if err != nil {
return nil, err
}
if st.Size() != 0 {
return nil, fmt.Errorf("non empty WAL file %s exists", wn)
}
}
info, err := f.Stat()
if err != nil {
return nil, err
}
switch sz := info.Size(); {
case sz == 0:
b := make([]byte, 16)
copy(b, []byte(magic))
if _, err := f.Write(b); err != nil {
return nil, err
}
filer := lldb.Filer(lldb.NewOSFiler(f))
filer = lldb.NewInnerFiler(filer, 16)
if filer, err = lldb.NewACIDFiler(filer, w); err != nil {
return nil, err
}
a, err := lldb.NewAllocator(filer, &lldb.Options{})
if err != nil {
return nil, err
}
a.Compress = true
s := &file{
a: a,
codec: newGobCoder(),
f0: f,
f: filer,
lck: lck,
name: f.Name(),
wal: w,
}
if err = s.BeginTransaction(); err != nil {
return nil, err
}
h, err := s.Create()
if err != nil {
return nil, err
}
if h != 1 { // root
log.Panic("internal error")
}
if h, err = s.a.Alloc(make([]byte, 8)); err != nil {
return nil, err
}
if h != 2 { // id
log.Panic("internal error")
}
close, closew = false, false
return s, s.Commit()
default:
b := make([]byte, 16)
if _, err := f.Read(b); err != nil {
return nil, err
}
if string(b[:len(magic)]) != magic {
return nil, fmt.Errorf("unknown file format")
}
filer := lldb.Filer(lldb.NewOSFiler(f))
filer = lldb.NewInnerFiler(filer, 16)
if filer, err = lldb.NewACIDFiler(filer, w); err != nil {
return nil, err
}
a, err := lldb.NewAllocator(filer, &lldb.Options{})
if err != nil {
return nil, err
}
bid, err := a.Get(nil, 2) // id
if err != nil {
return nil, err
}
if len(bid) != 8 {
return nil, fmt.Errorf("corrupted id |% x|", bid)
}
id := int64(0)
for _, v := range bid {
id = (id << 8) | int64(v)
}
a.Compress = true
s := &file{
a: a,
codec: newGobCoder(),
f0: f,
f: filer,
id: id,
lck: lck,
name: f.Name(),
wal: w,
}
close, closew = false, false
return s, nil
}
}