From b0565015ccb85c363ca8f8a682558a9a7c12948f Mon Sep 17 00:00:00 2001
From: Alexander Neumann <alexander@bumpern.de>
Date: Sun, 7 Aug 2016 14:51:19 +0200
Subject: [PATCH] Remove ReadSeeker

---
 src/restic/backend/readseeker.go      |  63 --------------
 src/restic/backend/readseeker_test.go | 114 --------------------------
 2 files changed, 177 deletions(-)
 delete mode 100644 src/restic/backend/readseeker.go
 delete mode 100644 src/restic/backend/readseeker_test.go

diff --git a/src/restic/backend/readseeker.go b/src/restic/backend/readseeker.go
deleted file mode 100644
index ea063e3f3..000000000
--- a/src/restic/backend/readseeker.go
+++ /dev/null
@@ -1,63 +0,0 @@
-package backend
-
-import (
-	"errors"
-	"io"
-)
-
-type readSeeker struct {
-	be     Backend
-	h      Handle
-	t      Type
-	name   string
-	offset int64
-	size   int64
-}
-
-// NewReadSeeker returns an io.ReadSeeker for the given object in the backend.
-func NewReadSeeker(be Backend, h Handle) io.ReadSeeker {
-	return &readSeeker{be: be, h: h}
-}
-
-func (rd *readSeeker) Read(p []byte) (int, error) {
-	n, err := rd.be.Load(rd.h, p, rd.offset)
-	rd.offset += int64(n)
-	return n, err
-}
-
-func (rd *readSeeker) Seek(offset int64, whence int) (n int64, err error) {
-	switch whence {
-	case 0:
-		rd.offset = offset
-	case 1:
-		rd.offset += offset
-	case 2:
-		if rd.size == 0 {
-			rd.size, err = rd.getSize()
-			if err != nil {
-				return 0, err
-			}
-		}
-
-		pos := rd.size + offset
-		if pos < 0 {
-			return 0, errors.New("invalid offset, before start of blob")
-		}
-
-		rd.offset = pos
-		return rd.offset, nil
-	default:
-		return 0, errors.New("invalid value for parameter whence")
-	}
-
-	return rd.offset, nil
-}
-
-func (rd *readSeeker) getSize() (int64, error) {
-	stat, err := rd.be.Stat(rd.h)
-	if err != nil {
-		return 0, err
-	}
-
-	return stat.Size, nil
-}
diff --git a/src/restic/backend/readseeker_test.go b/src/restic/backend/readseeker_test.go
deleted file mode 100644
index 013f2528e..000000000
--- a/src/restic/backend/readseeker_test.go
+++ /dev/null
@@ -1,114 +0,0 @@
-package backend_test
-
-import (
-	"bytes"
-	"io"
-	"math/rand"
-	"restic/backend"
-	"restic/backend/mem"
-	"testing"
-
-	. "restic/test"
-)
-
-func abs(a int) int {
-	if a < 0 {
-		return -a
-	}
-
-	return a
-}
-
-func loadAndCompare(t testing.TB, rd io.ReadSeeker, size int, offset int64, expected []byte) {
-	var (
-		pos int64
-		err error
-	)
-
-	if offset >= 0 {
-		pos, err = rd.Seek(offset, 0)
-	} else {
-		pos, err = rd.Seek(offset, 2)
-	}
-	if err != nil {
-		t.Errorf("Seek(%d, 0) returned error: %v", offset, err)
-		return
-	}
-
-	if offset >= 0 && pos != offset {
-		t.Errorf("pos after seek is wrong, want %d, got %d", offset, pos)
-	} else if offset < 0 && pos != int64(size)+offset {
-		t.Errorf("pos after relative seek is wrong, want %d, got %d", int64(size)+offset, pos)
-	}
-
-	buf := make([]byte, len(expected))
-	n, err := rd.Read(buf)
-
-	// if we requested data beyond the end of the file, ignore
-	// ErrUnexpectedEOF error
-	if offset > 0 && len(buf) > size && err == io.ErrUnexpectedEOF {
-		err = nil
-		buf = buf[:size]
-	}
-
-	if offset < 0 && len(buf) > abs(int(offset)) && err == io.ErrUnexpectedEOF {
-		err = nil
-		buf = buf[:abs(int(offset))]
-	}
-
-	if n != len(buf) {
-		t.Errorf("Load(%d, %d): wrong length returned, want %d, got %d",
-			len(buf), offset, len(buf), n)
-		return
-	}
-
-	if err != nil {
-		t.Errorf("Load(%d, %d): unexpected error: %v", len(buf), offset, err)
-		return
-	}
-
-	buf = buf[:n]
-	if !bytes.Equal(buf, expected) {
-		t.Errorf("Load(%d, %d) returned wrong bytes", len(buf), offset)
-		return
-	}
-}
-
-func TestReadSeeker(t *testing.T) {
-	b := mem.New()
-
-	length := rand.Intn(1<<24) + 2000
-
-	data := Random(23, length)
-	id := backend.Hash(data)
-
-	handle := backend.Handle{Type: backend.Data, Name: id.String()}
-	err := b.Save(handle, data)
-	if err != nil {
-		t.Fatalf("Save() error: %v", err)
-	}
-
-	for i := 0; i < 50; i++ {
-		l := rand.Intn(length + 2000)
-		o := rand.Intn(length + 2000)
-
-		if rand.Float32() > 0.5 {
-			o = -o
-		}
-
-		d := data
-		if o > 0 && o < len(d) {
-			d = d[o:]
-		} else {
-			o = len(d)
-			d = d[:0]
-		}
-
-		if l > 0 && l < len(d) {
-			d = d[:l]
-		}
-
-		rd := backend.NewReadSeeker(b, handle)
-		loadAndCompare(t, rd, len(data), int64(o), d)
-	}
-}