Add initial interop tests
diff --git a/tools/http2_interop/settings.go b/tools/http2_interop/settings.go
new file mode 100644
index 0000000..5a2b1ad
--- /dev/null
+++ b/tools/http2_interop/settings.go
@@ -0,0 +1,109 @@
+package http2interop
+
+import (
+ "encoding/binary"
+ "fmt"
+ "io"
+)
+
+const (
+ SETTINGS_ACK = 1
+)
+
+type SettingsFrame struct {
+ Header FrameHeader
+ Params []SettingsParameter
+}
+
+type SettingsIdentifier uint16
+
+const (
+ SettingsHeaderTableSize SettingsIdentifier = 1
+ SettingsEnablePush SettingsIdentifier = 2
+ SettingsMaxConcurrentStreams SettingsIdentifier = 3
+ SettingsInitialWindowSize SettingsIdentifier = 4
+ SettingsMaxFrameSize SettingsIdentifier = 5
+ SettingsMaxHeaderListSize SettingsIdentifier = 6
+)
+
+func (si SettingsIdentifier) String() string {
+ switch si {
+ case SettingsHeaderTableSize:
+ return "HEADER_TABLE_SIZE"
+ case SettingsEnablePush:
+ return "ENABLE_PUSH"
+ case SettingsMaxConcurrentStreams:
+ return "MAX_CONCURRENT_STREAMS"
+ case SettingsInitialWindowSize:
+ return "INITIAL_WINDOW_SIZE"
+ case SettingsMaxFrameSize:
+ return "MAX_FRAME_SIZE"
+ case SettingsMaxHeaderListSize:
+ return "MAX_HEADER_LIST_SIZE"
+ default:
+ return fmt.Sprintf("UNKNOWN(%d)", uint16(si))
+ }
+}
+
+type SettingsParameter struct {
+ Identifier SettingsIdentifier
+ Value uint32
+}
+
+func (f *SettingsFrame) GetHeader() *FrameHeader {
+ return &f.Header
+}
+
+func (f *SettingsFrame) ParsePayload(r io.Reader) error {
+ raw := make([]byte, f.Header.Length)
+ if _, err := io.ReadFull(r, raw); err != nil {
+ return err
+ }
+ return f.UnmarshalPayload(raw)
+}
+
+func (f *SettingsFrame) UnmarshalPayload(raw []byte) error {
+ if f.Header.Length != len(raw) {
+ return fmt.Errorf("Invalid Payload length %d != %d", f.Header.Length, len(raw))
+ }
+
+ if f.Header.Length%6 != 0 {
+ return fmt.Errorf("Invalid Payload length %d", f.Header.Length)
+ }
+
+ f.Params = make([]SettingsParameter, 0, f.Header.Length/6)
+ for i := 0; i < len(raw); i += 6 {
+ f.Params = append(f.Params, SettingsParameter{
+ Identifier: SettingsIdentifier(binary.BigEndian.Uint16(raw[i : i+2])),
+ Value: binary.BigEndian.Uint32(raw[i+2 : i+6]),
+ })
+ }
+ return nil
+}
+
+func (f *SettingsFrame) MarshalPayload() ([]byte, error) {
+ raw := make([]byte, 0, len(f.Params)*6)
+ for i, p := range f.Params {
+ binary.BigEndian.PutUint16(raw[i*6:i*6+2], uint16(p.Identifier))
+ binary.BigEndian.PutUint32(raw[i*6+2:i*6+6], p.Value)
+ }
+ return raw, nil
+}
+
+func (f *SettingsFrame) MarshalBinary() ([]byte, error) {
+ payload, err := f.MarshalPayload()
+ if err != nil {
+ return nil, err
+ }
+
+ f.Header.Length = len(payload)
+ f.Header.Type = SettingsFrameType
+ header, err := f.Header.MarshalBinary()
+ if err != nil {
+ return nil, err
+ }
+
+ header = append(header, payload...)
+
+ return header, nil
+}