Restarted some stuff so I can do it better.

Made a reader that can reade across data blocks if necessary
Still can't get things to read right

compressionoptions.go

@@ -4,7 +4,7 @@ import (
 	"compress/gzip"
 	"io"
 
-	"gopkg.in/src-d/go-git.v4/utils/ioutil"
+	"github.com/CalebQ42/GoSquashfs/bytereadwrite"
 )
 
 const (
@@ -18,19 +18,18 @@ const (
 
 //TODO: implement for each type of Options
 type CompressionOptions interface {
-	Decompress(*io.SectionReader, int) ([]byte, error)
+	Decompress(io.Reader) ([]byte, error)
 	DecompressCopy(*io.Reader, *io.Writer) (int, error)
-	Compress(*io.SectionReader, int) ([]byte, error)
+	Compress(*io.Reader) ([]byte, error)
 	CompressCopy(*io.Reader, *io.Writer) (int, error)
-	Reader(io.Reader) (*io.ReadCloser, error)
 }
 
 //TODO: Allow creation of options for compression.
 
 type gzipOptionsRaw struct {
-	compressionLevel int32
-	windowSize       int16
-	strategies       int16
+	CompressionLevel int32
+	WindowSize       int16
+	Strategies       int16
 }
 
 //GzipOptions is the options used for gzip compression. Backed by the raw format, with strategies parsed.
@@ -44,51 +43,6 @@ type GzipOptions struct {
 	FixedStretegy            bool
 }
 
-type byteWriterReader struct {
-	byts   []byte
-	offset int
-}
-
-func newByteReadWrite(length int) *byteWriterReader {
-	return &byteWriterReader{
-		byts:   make([]byte, length),
-		offset: 0,
-	}
-}
-
-func newByteReadWriteFromBytes(byts []byte) *byteWriterReader {
-	return &byteWriterReader{
-		byts:   byts,
-		offset: 0,
-	}
-}
-
-func (bwr *byteWriterReader) getBytes() []byte {
-	return bwr.byts
-}
-
-//Read reads the bytes.
-func (bwr *byteWriterReader) Read(byt []byte) (int, error) {
-	if len(bwr.byts) < bwr.offset+len(byt) {
-		bytesWritten := len(bwr.byts) - bwr.offset
-		for i := 0; i < bytesWritten; i++ {
-			byt[i] = bwr.byts[i+bwr.offset]
-		}
-		return bytesWritten, io.EOF
-	}
-	for i := 0; i < len(byt); i++ {
-		byt[i] = bwr.byts[bwr.offset+i]
-	}
-	bwr.offset += len(byt)
-	return len(byt), nil
-}
-
-//Write writes to the bytes. WILL expand to accept the incoming bytes.
-func (bwr *byteWriterReader) Write(byts []byte) (int, error) {
-	bwr.byts = append(bwr.byts, byts...)
-	return len(byts), nil
-}
-
 func NewGzipOptions(raw gzipOptionsRaw) *GzipOptions {
 	//TODO: parse strategies
 	return &GzipOptions{
@@ -96,18 +50,18 @@ func NewGzipOptions(raw gzipOptionsRaw) *GzipOptions {
 	}
 }
 
-func (gzipOp *GzipOptions) Decompress(rdr *io.SectionReader, blockSize int) ([]byte, error) {
+func (gzipOp *GzipOptions) Decompress(rdr io.Reader) ([]byte, error) {
 	gzipRdr, err := gzip.NewReader(rdr)
-	defer gzipRdr.Close()
+	// defer gzipRdr.Close()
 	if err != nil {
 		return nil, err
 	}
-	bytrw := newByteReadWrite(0)
+	bytrw := bytereadwrite.NewByteReaderWriter()
 	_, err = io.Copy(bytrw, gzipRdr)
 	if err != nil {
-		return bytrw.byts, err
+		return nil, err
 	}
-	return bytrw.byts, nil
+	return bytrw.GetBytes(), nil
 }
 
 func (gzipOp *GzipOptions) DecompressCopy(rdr *io.Reader, wrt *io.Writer) (int, error) {
@@ -120,15 +74,15 @@ func (gzipOp *GzipOptions) DecompressCopy(rdr *io.Reader, wrt *io.Writer) (int,
 	return int(n), err
 }
 
-func (gzipOp *GzipOptions) Compress(rdr *io.SectionReader, blockSize int) ([]byte, error) {
-	bytWrt := newByteReadWrite(0)
+func (gzipOp *GzipOptions) Compress(rdr *io.Reader) ([]byte, error) {
+	bytWrt := bytereadwrite.NewByteReaderWriter()
 	gzipWrt := gzip.NewWriter(bytWrt) //TODO: allow setting level
 	defer gzipWrt.Close()
-	_, err := io.Copy(gzipWrt, rdr)
+	_, err := io.Copy(gzipWrt, *rdr)
 	if err != nil {
-		return bytWrt.byts, err
+		return bytWrt.GetBytes(), err
 	}
-	return bytWrt.byts, nil
+	return bytWrt.GetBytes(), nil
 }
 
 func (gzipOp *GzipOptions) CompressCopy(rdr *io.Reader, wrt *io.Writer) (int, error) {
@@ -138,15 +92,9 @@ func (gzipOp *GzipOptions) CompressCopy(rdr *io.Reader, wrt *io.Writer) (int, er
 	return int(n), err
 }
 
-func (gzipOp *GzipOptions) Reader(rdr io.Reader) (*io.ReadCloser, error) {
-	read, err := gzip.NewReader(rdr)
-	redClo := ioutil.NewReadCloser(read, read)
-	return &redClo, err
-}
-
 type xzOptionsRaw struct {
-	dictionarySize    int32
-	executableFilters int32
+	DictionarySize    int32
+	ExecutableFilters int32
 }
 
 type XzOptions struct {
@@ -163,18 +111,18 @@ type XzOptions struct {
 func NewXzOption(raw xzOptionsRaw) XzOptions {
 	return XzOptions{
 		raw:          &raw,
-		Execx86:      raw.executableFilters&0x1 == 0x1,
-		ExecPower:    raw.executableFilters&0x2 == 0x2,
-		Execa64:      raw.executableFilters&0x4 == 0x4,
-		ExecArm:      raw.executableFilters&0x8 == 0x8,
-		ExecArmThumb: raw.executableFilters&0x10 == 0x10,
-		ExecSparc:    raw.executableFilters&0x20 == 0x20,
+		Execx86:      raw.ExecutableFilters&0x1 == 0x1,
+		ExecPower:    raw.ExecutableFilters&0x2 == 0x2,
+		Execa64:      raw.ExecutableFilters&0x4 == 0x4,
+		ExecArm:      raw.ExecutableFilters&0x8 == 0x8,
+		ExecArmThumb: raw.ExecutableFilters&0x10 == 0x10,
+		ExecSparc:    raw.ExecutableFilters&0x20 == 0x20,
 	}
 }
 
 type lz4OptionsRaw struct {
-	version int32
-	flags   int32
+	Version int32
+	Flags   int32
 }
 
 //ZstdOptions is the options set for zstdOptions
@@ -183,6 +131,6 @@ type ZstdOptions struct {
 }
 
 type lzoOptionsRaw struct {
-	algorithm        int32
-	compressionLevel int32
+	Algorithm        int32
+	CompressionLevel int32
 }