/*
Read a particular segmentFileName. Note that this may return IO error
if a commit is in process.
*/
func (sis *SegmentInfos) Read(directory store.Directory, segmentFileName string) (err error) {
// fmt.Printf("Reading segment info from %v...\n", segmentFileName)
// Clear any previous segments:
sis.Clear()
sis.generation = GenerationFromSegmentsFileName(segmentFileName)
sis.lastGeneration = sis.generation
var input store.ChecksumIndexInput
if input, err = directory.OpenChecksumInput(segmentFileName, store.IO_CONTEXT_READ); err != nil {
return
}
var success = false
defer func() {
if !success {
// Clear any segment infos we had loaded so we
// have a clean slate on retry:
sis.Clear()
util.CloseWhileSuppressingError(input)
} else {
err = input.Close()
}
}()
var format int
if format, err = asInt(input.ReadInt()); err != nil {
return
}
var actualFormat int
if format == codec.CODEC_MAGIC {
// 4.0+
if actualFormat, err = asInt(codec.CheckHeaderNoMagic(input, "segments", VERSION_40, VERSION_49)); err != nil {
return
}
if sis.version, err = input.ReadLong(); err != nil {
return
}
if sis.counter, err = asInt(input.ReadInt()); err != nil {
return
}
var numSegments int
if numSegments, err = asInt(input.ReadInt()); err != nil {
return
} else if numSegments < 0 {
return errors.New(fmt.Sprintf("invalid segment count: %v (resource: %v)", numSegments, input))
}
var segName, codecName string
var fCodec Codec
var delGen, fieldInfosGen, dvGen int64
var delCount int
for seg := 0; seg < numSegments; seg++ {
if segName, err = input.ReadString(); err != nil {
return
}
if codecName, err = input.ReadString(); err != nil {
return
}
fCodec = LoadCodec(codecName)
assert2(fCodec != nil, "Invalid codec name: %v", codecName)
// fmt.Printf("SIS.read seg=%v codec=%v\n", seg, fCodec)
var info *SegmentInfo
if info, err = fCodec.SegmentInfoFormat().SegmentInfoReader().Read(directory, segName, store.IO_CONTEXT_READ); err != nil {
return
}
info.SetCodec(fCodec)
if delGen, err = input.ReadLong(); err != nil {
return
}
if delCount, err = asInt(input.ReadInt()); err != nil {
return
} else if delCount < 0 || delCount > info.DocCount() {
return errors.New(fmt.Sprintf(
"invalid deletion count: %v vs docCount=%v (resource: %v)",
delCount, info.DocCount(), input))
}
fieldInfosGen = -1
if actualFormat >= VERSION_46 {
if fieldInfosGen, err = input.ReadLong(); err != nil {
return
}
}
dvGen = -1
if actualFormat >= VERSION_49 {
if dvGen, err = input.ReadLong(); err != nil {
return
}
} else {
dvGen = fieldInfosGen
}
siPerCommit := NewSegmentCommitInfo(info, delCount, delGen, fieldInfosGen, dvGen)
if actualFormat >= VERSION_46 {
if actualFormat < VERSION_49 {
panic("not implemented yet")
} else {
var ss map[string]bool
if ss, err = input.ReadStringSet(); err != nil {
return err
}
siPerCommit.SetFieldInfosFiles(ss)
var dvUpdatesFiles map[int]map[string]bool
var numDVFields int
if numDVFields, err = asInt(input.ReadInt()); err != nil {
return err
}
if numDVFields == 0 {
dvUpdatesFiles = make(map[int]map[string]bool)
} else {
panic("not implemented yet")
}
siPerCommit.SetDocValuesUpdatesFiles(dvUpdatesFiles)
}
}
sis.Segments = append(sis.Segments, siPerCommit)
}
if sis.userData, err = input.ReadStringStringMap(); err != nil {
return err
}
} else {
// TODO support <4.0 index
panic("Index format pre-4.0 not supported yet")
}
if actualFormat >= VERSION_48 {
if _, err = codec.CheckFooter(input); err != nil {
return
}
} else {
var checksumNow = int64(input.Checksum())
var checksumThen int64
if checksumThen, err = input.ReadLong(); err != nil {
return
}
if checksumNow != checksumThen {
return errors.New(fmt.Sprintf(
"checksum mismatch in segments file: %v vs %v (resource: %v)",
checksumNow, checksumThen, input))
}
if err = codec.CheckEOF(input); err != nil {
return
}
}
success = true
return nil
}
// Sole constructor
func newCompressingStoredFieldsReader(d store.Directory,
si *model.SegmentInfo, segmentSuffix string,
fn model.FieldInfos, ctx store.IOContext, formatName string,
compressionMode CompressionMode) (r *CompressingStoredFieldsReader, err error) {
r = &CompressingStoredFieldsReader{}
r.compressionMode = compressionMode
segment := si.Name
r.fieldInfos = fn
r.numDocs = si.DocCount()
var indexStream store.ChecksumIndexInput
success := false
defer func() {
if !success {
util.CloseWhileSuppressingError(r, indexStream)
}
}()
indexStreamFN := util.SegmentFileName(segment, segmentSuffix, lucene40.FIELDS_INDEX_EXTENSION)
fieldsStreamFN := util.SegmentFileName(segment, segmentSuffix, lucene40.FIELDS_EXTENSION)
// Load the index into memory
if indexStream, err = d.OpenChecksumInput(indexStreamFN, ctx); err != nil {
return nil, err
}
codecNameIdx := formatName + CODEC_SFX_IDX
if r.version, err = int32AsInt(codec.CheckHeader(indexStream, codecNameIdx,
VERSION_START, VERSION_CURRENT)); err != nil {
return nil, err
}
assert(int64(codec.HeaderLength(codecNameIdx)) == indexStream.FilePointer())
if r.indexReader, err = newCompressingStoredFieldsIndexReader(indexStream, si); err != nil {
return nil, err
}
var maxPointer int64 = -1
if r.version >= VERSION_CHECKSUM {
if maxPointer, err = indexStream.ReadVLong(); err != nil {
return nil, err
}
if _, err = codec.CheckFooter(indexStream); err != nil {
return nil, err
}
} else {
if err = codec.CheckEOF(indexStream); err != nil {
return nil, err
}
}
if err = indexStream.Close(); err != nil {
return nil, err
}
indexStream = nil
// Open the data file and read metadata
if r.fieldsStream, err = d.OpenInput(fieldsStreamFN, ctx); err != nil {
return nil, err
}
if r.version >= VERSION_CHECKSUM {
if maxPointer+codec.FOOTER_LENGTH != r.fieldsStream.Length() {
return nil, errors.New(fmt.Sprintf(
"Invalid fieldsStream maxPointer (file truncated?): maxPointer=%v, length=%v",
maxPointer, r.fieldsStream.Length()))
}
} else {
maxPointer = r.fieldsStream.Length()
}
r.maxPointer = maxPointer
codecNameDat := formatName + CODEC_SFX_DAT
var fieldsVersion int
if fieldsVersion, err = int32AsInt(codec.CheckHeader(r.fieldsStream,
codecNameDat, VERSION_START, VERSION_CURRENT)); err != nil {
return nil, err
}
assert2(r.version == fieldsVersion,
"Version mismatch between stored fields index and data: %v != %v",
r.version, fieldsVersion)
assert(int64(codec.HeaderLength(codecNameDat)) == r.fieldsStream.FilePointer())
r.chunkSize = -1
if r.version >= VERSION_BIG_CHUNKS {
if r.chunkSize, err = int32AsInt(r.fieldsStream.ReadVInt()); err != nil {
return nil, err
}
}
if r.packedIntsVersion, err = int32AsInt(r.fieldsStream.ReadVInt()); err != nil {
return nil, err
}
r.decompressor = compressionMode.NewDecompressor()
r.bytes = make([]byte, 0)
if r.version >= VERSION_CHECKSUM {
// NOTE: data file is too costly to verify checksum against all the
// bytes on open, but fo rnow we at least verify proper structure
// of the checksum footer: which looks for FOOTER_MATIC +
// algorithmID. This is cheap and can detect some forms of
// corruption such as file trucation.
if _, err = codec.RetrieveChecksum(r.fieldsStream); err != nil {
return nil, err
}
}
success = true
return r, nil
}