/
pack.go
80 lines (65 loc) · 1.56 KB
/
pack.go
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package git
// PackIndexItem ...
type PackIndexItem struct {
OID ObjectID
Offset int64 // the offset in pack file
CRC32 uint32
// ext
PID PackID
Exists bool
Index int64 // the index in idx table
Length int64
Type ObjectType
PackedType PackedObjectType // in-pack entity
}
// PackIndexHead ...
type PackIndexHead struct {
Version int // 1 or 2
Total int64
FanOut PackIdxFanOut
}
// PackIndex ...
type PackIndex struct {
Head PackIndexHead
Items []*PackIndexItem
}
// PackedObjectHeader ...
type PackedObjectHeader struct {
Type PackedObjectType
Size int64
}
// PackedObjectHeaderEx ...
type PackedObjectHeaderEx struct {
PackedObjectHeader
PID PackID
OID ObjectID
Offset int64 // head(type+length)
// Offset1 int64 // end(type+length)
// Offset2 int64 // head(raw_data)
// Offset3 int64 // end(raw_data)
CRC32 int64 // = idx.item[n].crc32
DeltaRef ObjectID
DeltaOffset int64
// // for debug
// DeltaOffsetAbs int64 //
}
// GetDeltaParentOffset 计算 delta-parent 的绝对位置
func (inst *PackedObjectHeaderEx) GetDeltaParentOffset() int64 {
if inst.Type == PackedDeltaOFS {
return inst.Offset - inst.DeltaOffset
}
return 0
}
////////////////////////////////////////////////////////////////////////////////
// PackIdxFanOut ...
type PackIdxFanOut struct {
Data [256]uint32
}
// Total 返回总条数
func (inst *PackIdxFanOut) Total() int64 {
list := inst.Data[:]
size := len(list)
n := list[size-1]
return int64(n)
}
////////////////////////////////////////////////////////////////////////////////