@ -6,11 +6,7 @@ package git
import ( import (
"bytes" "bytes"
"encoding/hex" "encoding/hex"
"errors"
"fmt" "fmt"
"hash"
"strconv"
"strings"
) )
type ObjectID interface { type ObjectID interface {
@ -35,48 +31,36 @@ func (*Sha1Hash) Type() ObjectFormat { return Sha1ObjectFormat }
var _ ObjectID = & Sha1Hash { } var _ ObjectID = & Sha1Hash { }
// EmptyObjectID creates a new ObjectID from an object format hash name
func MustIDFromString ( hexHash string ) ObjectID {
func EmptyObjectID ( objectFormatName string ) ( ObjectID , error ) { id , err := NewIDFromString ( hexHash )
objectFormat := ObjectFormatFromName ( objectFormatName ) if err != nil {
if objectFormat != nil { panic ( err )
return objectFormat . EmptyObjectID ( ) , nil
} }
return id
return nil , errors . New ( "unsupported hash type" )
} }
func IDFromRaw ( h ObjectFormat , b [ ] byte ) ( ObjectID , error ) { func NewIDFromString ( hexHash string ) ( ObjectID , error ) {
if len ( b ) != h . FullLength ( ) / 2 { var theObjectFormat ObjectFormat
return h . EmptyObjectID ( ) , fmt . Errorf ( "length must be %d: %v" , h . FullLength ( ) , b ) for _ , objectFormat := range SupportedObjectFormats {
if len ( hexHash ) == objectFormat . FullLength ( ) {
theObjectFormat = objectFormat
break
}
} }
return h . MustID ( b ) , nil
}
func MustIDFromString ( h ObjectFormat , s string ) ObjectID { if theObjectFormat == nil {
b , _ := hex . DecodeString ( s ) return nil , fmt . Errorf ( "length %d has no matched object format: %s" , len ( hexHash ) , hexHash )
return h . MustID ( b )
}
func genericIDFromString ( h ObjectFormat , s string ) ( ObjectID , error ) {
s = strings . TrimSpace ( s )
if len ( s ) != h . FullLength ( ) {
return h . EmptyObjectID ( ) , fmt . Errorf ( "length must be %d: %s" , h . FullLength ( ) , s )
} }
b , err := hex . DecodeString ( s )
b , err := hex . DecodeString ( hexHash )
if err != nil { if err != nil {
return h . EmptyObjectID ( ) , err return nil , err
} }
return h . NewID ( b )
}
func IDFromString ( hexHash string ) ( ObjectID , error ) { if len ( b ) != theObjectFormat . FullLength ( ) / 2 {
for _ , objectFormat := range SupportedObjectFormats { return theObjectFormat . EmptyObjectID ( ) , fmt . Errorf ( "length must be %d: %v" , theObjectFormat . FullLength ( ) , b )
if len ( hexHash ) == objectFormat . FullLength ( ) {
return objectFormat . NewIDFromString ( hexHash )
}
} }
return theObjectFormat . MustID ( b ) , nil
return nil , fmt . Errorf ( "invalid hash hex string: '%s' len: %d" , hexHash , len ( hexHash ) )
} }
func IsEmptyCommitID ( commitID string ) bool { func IsEmptyCommitID ( commitID string ) bool {
@ -84,7 +68,7 @@ func IsEmptyCommitID(commitID string) bool {
return true return true
} }
id , err := IDFromString ( commitID ) id , err := New IDFromString( commitID )
if err != nil { if err != nil {
return false return false
} }
@ -92,37 +76,9 @@ func IsEmptyCommitID(commitID string) bool {
return id . IsZero ( ) return id . IsZero ( )
} }
// HasherInterface is a struct that will generate a Hash
type HasherInterface interface {
hash . Hash
HashSum ( ) ObjectID
}
type Sha1Hasher struct {
hash . Hash
}
// ComputeBlobHash compute the hash for a given blob content
// ComputeBlobHash compute the hash for a given blob content
func ComputeBlobHash ( hashType ObjectFormat , content [ ] byte ) ObjectID { func ComputeBlobHash ( hashType ObjectFormat , content [ ] byte ) ObjectID {
return ComputeHash ( hashType , ObjectBlob , content ) return hashType . ComputeHash ( ObjectBlob , content )
}
// ComputeHash compute the hash for a given ObjectType and content
func ComputeHash ( hashType ObjectFormat , t ObjectType , content [ ] byte ) ObjectID {
h := hashType . NewHasher ( )
_ , _ = h . Write ( t . Bytes ( ) )
_ , _ = h . Write ( [ ] byte ( " " ) )
_ , _ = h . Write ( [ ] byte ( strconv . FormatInt ( int64 ( len ( content ) ) , 10 ) ) )
_ , _ = h . Write ( [ ] byte { 0 } )
return h . HashSum ( )
}
// HashSum generates a SHA1 for the provided hash
func ( h * Sha1Hasher ) HashSum ( ) ObjectID {
var sha1 Sha1Hash
copy ( sha1 [ : ] , h . Hash . Sum ( nil ) )
return & sha1
} }
type ErrInvalidSHA struct { type ErrInvalidSHA struct {
Lunny Xiao
11 months ago
committed by
GitHub