internal/compress: Import flate and such from klauspost/compress

1 files changed, 0 insertions, 72 deletions

diff --git a/internal/zlib/writer_header.go b/internal/zlib/writer_header.go
deleted file mode 100644
index 29b02fb2..00000000
--- a/internal/zlib/writer_header.go
+++ /dev/null
@@ -1,72 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package zlib
-
-import (
-	"encoding/binary"
-
-	"codeberg.org/lindenii/furgit/internal/adler32"
-
-	"github.com/klauspost/compress/flate"
-)
-
-// writeHeader writes the ZLIB header.
-func (z *Writer) writeHeader() (err error) {
-	z.wroteHeader = true
-	// ZLIB has a two-byte header (as documented in RFC 1950).
-	// The first four bits is the CINFO (compression info), which is 7 for the default deflate window size.
-	// The next four bits is the CM (compression method), which is 8 for deflate.
-	z.scratch[0] = 0x78
-	// The next two bits is the FLEVEL (compression level). The four values are:
-	// 0=fastest, 1=fast, 2=default, 3=best.
-	// The next bit, FDICT, is set if a dictionary is given.
-	// The final five FCHECK bits form a mod-31 checksum.
-	switch z.level {
-	case -2, 0, 1:
-		z.scratch[1] = 0 << 6
-	case 2, 3, 4, 5:
-		z.scratch[1] = 1 << 6
-	case 6, -1:
-		z.scratch[1] = 2 << 6
-	case 7, 8, 9:
-		z.scratch[1] = 3 << 6
-	default:
-		panic("unreachable")
-	}
-
-	if z.dict != nil {
-		z.scratch[1] |= 1 << 5
-	}
-
-	z.scratch[1] += uint8(31 - binary.BigEndian.Uint16(z.scratch[:2])%31) //#nosec G115
-
-	_, err = z.w.Write(z.scratch[0:2])
-	if err != nil {
-		return err
-	}
-
-	if z.dict != nil {
-		// The next four bytes are the Adler-32 checksum of the dictionary.
-		binary.BigEndian.PutUint32(z.scratch[:], adler32.Checksum(z.dict))
-
-		_, err = z.w.Write(z.scratch[0:4])
-		if err != nil {
-			return err
-		}
-	}
-
-	if z.compressor == nil {
-		// Initialize deflater unless the Writer is being reused
-		// after a Reset call.
-		z.compressor, err = flate.NewWriterDict(z.w, z.level, z.dict)
-		if err != nil {
-			return err
-		}
-
-		z.digest = adler32.New()
-	}
-
-	return nil
-}