1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164
|
package packfile
import (
"github.com/go-git/go-git/v5/plumbing"
)
// ObjectToPack is a representation of an object that is going to be into a
// pack file.
type ObjectToPack struct {
// The main object to pack, it could be any object, including deltas
Object plumbing.EncodedObject
// Base is the object that a delta is based on (it could be also another delta).
// If the main object is not a delta, Base will be null
Base *ObjectToPack
// Original is the object that we can generate applying the delta to
// Base, or the same object as Object in the case of a non-delta
// object.
Original plumbing.EncodedObject
// Depth is the amount of deltas needed to resolve to obtain Original
// (delta based on delta based on ...)
Depth int
// offset in pack when object has been already written, or 0 if it
// has not been written yet
Offset int64
// Information from the original object
resolvedOriginal bool
originalType plumbing.ObjectType
originalSize int64
originalHash plumbing.Hash
}
// newObjectToPack creates a correct ObjectToPack based on a non-delta object
func newObjectToPack(o plumbing.EncodedObject) *ObjectToPack {
return &ObjectToPack{
Object: o,
Original: o,
}
}
// newDeltaObjectToPack creates a correct ObjectToPack for a delta object, based on
// his base (could be another delta), the delta target (in this case called original),
// and the delta Object itself
func newDeltaObjectToPack(base *ObjectToPack, original, delta plumbing.EncodedObject) *ObjectToPack {
return &ObjectToPack{
Object: delta,
Base: base,
Original: original,
Depth: base.Depth + 1,
}
}
// BackToOriginal converts that ObjectToPack to a non-deltified object if it was one
func (o *ObjectToPack) BackToOriginal() {
if o.IsDelta() && o.Original != nil {
o.Object = o.Original
o.Base = nil
o.Depth = 0
}
}
// IsWritten returns if that ObjectToPack was
// already written into the packfile or not
func (o *ObjectToPack) IsWritten() bool {
return o.Offset > 1
}
// MarkWantWrite marks this ObjectToPack as WantWrite
// to avoid delta chain loops
func (o *ObjectToPack) MarkWantWrite() {
o.Offset = 1
}
// WantWrite checks if this ObjectToPack was marked as WantWrite before
func (o *ObjectToPack) WantWrite() bool {
return o.Offset == 1
}
// SetOriginal sets both Original and saves size, type and hash. If object
// is nil Original is set but previous resolved values are kept
func (o *ObjectToPack) SetOriginal(obj plumbing.EncodedObject) {
o.Original = obj
o.SaveOriginalMetadata()
}
// SaveOriginalMetadata saves size, type and hash of Original object
func (o *ObjectToPack) SaveOriginalMetadata() {
if o.Original != nil {
o.originalSize = o.Original.Size()
o.originalType = o.Original.Type()
o.originalHash = o.Original.Hash()
o.resolvedOriginal = true
}
}
// CleanOriginal sets Original to nil
func (o *ObjectToPack) CleanOriginal() {
o.Original = nil
}
func (o *ObjectToPack) Type() plumbing.ObjectType {
if o.Original != nil {
return o.Original.Type()
}
if o.resolvedOriginal {
return o.originalType
}
if o.Base != nil {
return o.Base.Type()
}
if o.Object != nil {
return o.Object.Type()
}
panic("cannot get type")
}
func (o *ObjectToPack) Hash() plumbing.Hash {
if o.Original != nil {
return o.Original.Hash()
}
if o.resolvedOriginal {
return o.originalHash
}
do, ok := o.Object.(plumbing.DeltaObject)
if ok {
return do.ActualHash()
}
panic("cannot get hash")
}
func (o *ObjectToPack) Size() int64 {
if o.Original != nil {
return o.Original.Size()
}
if o.resolvedOriginal {
return o.originalSize
}
do, ok := o.Object.(plumbing.DeltaObject)
if ok {
return do.ActualSize()
}
panic("cannot get ObjectToPack size")
}
func (o *ObjectToPack) IsDelta() bool {
return o.Base != nil
}
func (o *ObjectToPack) SetDelta(base *ObjectToPack, delta plumbing.EncodedObject) {
o.Object = delta
o.Base = base
o.Depth = base.Depth + 1
}
|