swarm: network rewrite merge

swarm/network/bitvector/bitvector.go

@@ -0,0 +1,66 @@
+// Copyright 2018 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package bitvector
+
+import (
+	"errors"
+)
+
+var errInvalidLength = errors.New("invalid length")
+
+type BitVector struct {
+	len int
+	b   []byte
+}
+
+func New(l int) (bv *BitVector, err error) {
+	return NewFromBytes(make([]byte, l/8+1), l)
+}
+
+func NewFromBytes(b []byte, l int) (bv *BitVector, err error) {
+	if l <= 0 {
+		return nil, errInvalidLength
+	}
+	if len(b)*8 < l {
+		return nil, errInvalidLength
+	}
+	return &BitVector{
+		len: l,
+		b:   b,
+	}, nil
+}
+
+func (bv *BitVector) Get(i int) bool {
+	bi := i / 8
+	return bv.b[bi]&(0x1<<uint(i%8)) != 0
+}
+
+func (bv *BitVector) Set(i int, v bool) {
+	bi := i / 8
+	cv := bv.Get(i)
+	if cv != v {
+		bv.b[bi] ^= 0x1 << uint8(i%8)
+	}
+}
+
+func (bv *BitVector) Bytes() []byte {
+	return bv.b
+}
+
+func (bv *BitVector) Length() int {
+	return bv.len
+}

swarm/network/bitvector/bitvector_test.go

@@ -0,0 +1,104 @@
+// Copyright 2018 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package bitvector
+
+import "testing"
+
+func TestBitvectorNew(t *testing.T) {
+	_, err := New(0)
+	if err != errInvalidLength {
+		t.Errorf("expected err %v, got %v", errInvalidLength, err)
+	}
+
+	_, err = NewFromBytes(nil, 0)
+	if err != errInvalidLength {
+		t.Errorf("expected err %v, got %v", errInvalidLength, err)
+	}
+
+	_, err = NewFromBytes([]byte{0}, 9)
+	if err != errInvalidLength {
+		t.Errorf("expected err %v, got %v", errInvalidLength, err)
+	}
+
+	_, err = NewFromBytes(make([]byte, 8), 8)
+	if err != nil {
+		t.Error(err)
+	}
+}
+
+func TestBitvectorGetSet(t *testing.T) {
+	for _, length := range []int{
+		1,
+		2,
+		4,
+		8,
+		9,
+		15,
+		16,
+	} {
+		bv, err := New(length)
+		if err != nil {
+			t.Errorf("error for length %v: %v", length, err)
+		}
+
+		for i := 0; i < length; i++ {
+			if bv.Get(i) {
+				t.Errorf("expected false for element on index %v", i)
+			}
+		}
+
+		func() {
+			defer func() {
+				if err := recover(); err == nil {
+					t.Errorf("expecting panic")
+				}
+			}()
+			bv.Get(length + 8)
+		}()
+
+		for i := 0; i < length; i++ {
+			bv.Set(i, true)
+			for j := 0; j < length; j++ {
+				if j == i {
+					if !bv.Get(j) {
+						t.Errorf("element on index %v is not set to true", i)
+					}
+				} else {
+					if bv.Get(j) {
+						t.Errorf("element on index %v is not false", i)
+					}
+				}
+			}
+
+			bv.Set(i, false)
+
+			if bv.Get(i) {
+				t.Errorf("element on index %v is not set to false", i)
+			}
+		}
+	}
+}
+
+func TestBitvectorNewFromBytesGet(t *testing.T) {
+	bv, err := NewFromBytes([]byte{8}, 8)
+	if err != nil {
+		t.Error(err)
+	}
+	if !bv.Get(3) {
+		t.Fatalf("element 3 is not set to true: state %08b", bv.b[0])
+	}
+}