chenge bls library

bls/bititerator.go

@@ -0,0 +1,24 @@
+package bls
+
+// BitIterator is an iterator through bits.
+type BitIterator struct {
+	arr []uint64
+	n   uint
+}
+
+// NewBitIterator creates a new bit iterator given an array of ints.
+func NewBitIterator(arr []uint64) BitIterator {
+	return BitIterator{arr, uint(len(arr) * 64)}
+}
+
+// Next returns the next bit in the bit iterator with the
+// second return value as true when finished.
+func (bi *BitIterator) Next() (bool, bool) {
+	if bi.n == 0 {
+		return false, true
+	}
+	bi.n--
+	part := bi.n / 64
+	bit := bi.n - (part * 64)
+	return bi.arr[part]&(1<<bit) > 0, false
+}

bls/bititerator_test.go

@@ -0,0 +1,26 @@
+package bls_test
+
+import (
+	"testing"
+
+	"github.com/phoreproject/bls"
+)
+
+func TestBitIterator(t *testing.T) {
+	a := bls.NewBitIterator([]uint64{0xa953d79b83f6ab59, 0x6dea2059e200bd39})
+	expected := "01101101111010100010000001011001111000100000000010111101001110011010100101010011110101111001101110000011111101101010101101011001"
+
+	for _, e := range expected {
+		bit, done := a.Next()
+		if done {
+			t.Fatal("iterator finished too soon")
+		}
+		if bit != (e == '1') {
+			t.Fatal("invalid bit")
+		}
+	}
+
+	if _, done := a.Next(); done != true {
+		t.Fatal("iterator did not finish in time")
+	}
+}

bls/curve_test.go

@@ -0,0 +1 @@
+package bls_test