1 files changed, 137 insertions, 0 deletions
diff --git a/pkg/tcpip/buffer/view_test.go b/pkg/tcpip/buffer/view_test.go
index ebc3a17b7..106e1994c 100644
--- a/pkg/tcpip/buffer/view_test.go
+++ b/pkg/tcpip/buffer/view_test.go
@@ -233,3 +233,140 @@ func TestToClone(t *testing.T) {
 		})
 	}
 }
+
+func TestVVReadToVV(t *testing.T) {
+	testCases := []struct {
+		comment     string
+		vv          VectorisedView
+		bytesToRead int
+		wantBytes   string
+		leftVV      VectorisedView
+	}{
+		{
+			comment:     "large VV, short read",
+			vv:          vv(30, "012345678901234567890123456789"),
+			bytesToRead: 10,
+			wantBytes:   "0123456789",
+			leftVV:      vv(20, "01234567890123456789"),
+		},
+		{
+			comment:     "largeVV, multiple views, short read",
+			vv:          vv(13, "123", "345", "567", "8910"),
+			bytesToRead: 6,
+			wantBytes:   "123345",
+			leftVV:      vv(7, "567", "8910"),
+		},
+		{
+			comment:     "smallVV (multiple views), large read",
+			vv:          vv(3, "1", "2", "3"),
+			bytesToRead: 10,
+			wantBytes:   "123",
+			leftVV:      vv(0, ""),
+		},
+		{
+			comment:     "smallVV (single view), large read",
+			vv:          vv(1, "1"),
+			bytesToRead: 10,
+			wantBytes:   "1",
+			leftVV:      vv(0, ""),
+		},
+		{
+			comment:     "emptyVV, large read",
+			vv:          vv(0, ""),
+			bytesToRead: 10,
+			wantBytes:   "",
+			leftVV:      vv(0, ""),
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.comment, func(t *testing.T) {
+			var readTo VectorisedView
+			inSize := tc.vv.Size()
+			copied := tc.vv.ReadToVV(&readTo, tc.bytesToRead)
+			if got, want := copied, len(tc.wantBytes); got != want {
+				t.Errorf("incorrect number of bytes copied returned in ReadToVV got: %d, want: %d, tc: %+v", got, want, tc)
+			}
+			if got, want := string(readTo.ToView()), tc.wantBytes; got != want {
+				t.Errorf("unexpected content in readTo got: %s, want: %s", got, want)
+			}
+			if got, want := tc.vv.Size(), inSize-copied; got != want {
+				t.Errorf("test VV has incorrect size after reading got: %d, want: %d, tc.vv: %+v", got, want, tc.vv)
+			}
+			if got, want := string(tc.vv.ToView()), string(tc.leftVV.ToView()); got != want {
+				t.Errorf("unexpected data left in vv after read got: %+v, want: %+v", got, want)
+			}
+		})
+	}
+}
+
+func TestVVRead(t *testing.T) {
+	testCases := []struct {
+		comment     string
+		vv          VectorisedView
+		bytesToRead int
+		readBytes   string
+		leftBytes   string
+		wantError   bool
+	}{
+		{
+			comment:     "large VV, short read",
+			vv:          vv(30, "012345678901234567890123456789"),
+			bytesToRead: 10,
+			readBytes:   "0123456789",
+			leftBytes:   "01234567890123456789",
+		},
+		{
+			comment:     "largeVV, multiple buffers, short read",
+			vv:          vv(13, "123", "345", "567", "8910"),
+			bytesToRead: 6,
+			readBytes:   "123345",
+			leftBytes:   "5678910",
+		},
+		{
+			comment:     "smallVV, large read",
+			vv:          vv(3, "1", "2", "3"),
+			bytesToRead: 10,
+			readBytes:   "123",
+			leftBytes:   "",
+		},
+		{
+			comment:     "smallVV, large read",
+			vv:          vv(1, "1"),
+			bytesToRead: 10,
+			readBytes:   "1",
+			leftBytes:   "",
+		},
+		{
+			comment:     "emptyVV, large read",
+			vv:          vv(0, ""),
+			bytesToRead: 10,
+			readBytes:   "",
+			wantError:   true,
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.comment, func(t *testing.T) {
+			readTo := NewView(tc.bytesToRead)
+			inSize := tc.vv.Size()
+			copied, err := tc.vv.Read(readTo)
+			if !tc.wantError && err != nil {
+				t.Fatalf("unexpected error in tc.vv.Read(..) = %s", err)
+			}
+			readTo = readTo[:copied]
+			if got, want := copied, len(tc.readBytes); got != want {
+				t.Errorf("incorrect number of bytes copied returned in ReadToVV got: %d, want: %d, tc.vv: %+v", got, want, tc.vv)
+			}
+			if got, want := string(readTo), tc.readBytes; got != want {
+				t.Errorf("unexpected data in readTo got: %s, want: %s", got, want)
+			}
+			if got, want := tc.vv.Size(), inSize-copied; got != want {
+				t.Errorf("test VV has incorrect size after reading got: %d, want: %d, tc.vv: %+v", got, want, tc.vv)
+			}
+			if got, want := string(tc.vv.ToView()), tc.leftBytes; got != want {
+				t.Errorf("vv has incorrect data after Read got: %s, want: %s", got, want)
+			}
+		})
+	}
+}