go-bsdiff
Pure Go implementation of bsdiff 4.
bsdiff and bspatch are tools for building and applying patches to binary files. By using suffix sorting (specifically, Larsson and Sadakane's qsufsort) and taking advantage of how executable files change.
The package can be used as a library (pkg/bsdiff pkg/bspatch) or as a cli program (cmd/bsdiff cmd/bspatch).
As a library
Bsdiff Bytes
package main
import (
"fmt"
"bytes"
"github.com/gabstv/go-bsdiff/pkg/bsdiff"
"github.com/gabstv/go-bsdiff/pkg/bspatch"
)
func main(){
// example files
oldfile := []byte{0xfa, 0xdd, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff}
newfile := []byte{0xfa, 0xdd, 0x00, 0x00, 0x00, 0xee, 0xee, 0x00, 0x00, 0xff, 0xfe, 0xfe}
// generate a BSDIFF4 patch
patch, err := bsdiff.Bytes(oldfile, newfile)
if err != nil {
panic(err)
}
fmt.Println(patch)
// Apply a BSDIFF4 patch
newfile2, err := bspatch.Bytes(oldfile, patch)
if err != nil {
panic(err)
}
if !bytes.Equal(newfile, newfile2) {
panic()
}
}
Bsdiff Reader
package main
import (
"fmt"
"bytes"
"github.com/gabstv/go-bsdiff/pkg/bsdiff"
"github.com/gabstv/go-bsdiff/pkg/bspatch"
)
func main(){
oldrdr := bytes.NewReader([]byte{0xfa, 0xdd, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff})
newrdr := bytes.NewReader([]byte{0xfa, 0xdd, 0x00, 0x00, 0x00, 0xee, 0xee, 0x00, 0x00, 0xff, 0xfe, 0xfe})
patch := new(bytes.Buffer)
// generate a BSDIFF4 patch
if err := bsdiff.Reader(oldrdr, newrdr, patch); err != nil {
panic(err)
}
newpatchedf := new(bytes.Buffer)
oldrdr.Seek(0, 0)
// Apply a BSDIFF4 patch
if err := bspatch.Reader(oldrdr, newpatchedf, patch); err != nil {
panic(err)
}
fmt.Println(newpatchedf.Bytes())
}
As a program (CLI)
go get -u -v github.com/gabstv/go-bsdiff/cmd/...
bsdiff oldfile newfile patch
bspatch oldfile newfile2 patch