Initial QSfera import

Server/vendor/github.com/segmentio/kafka-go/protocol/request.go

@@ -0,0 +1,134 @@
+package protocol
+
+import (
+	"fmt"
+	"io"
+)
+
+func ReadRequest(r io.Reader) (apiVersion int16, correlationID int32, clientID string, msg Message, err error) {
+	d := &decoder{reader: r, remain: 4}
+	size := d.readInt32()
+
+	if err = d.err; err != nil {
+		err = dontExpectEOF(err)
+		return
+	}
+
+	d.remain = int(size)
+	apiKey := ApiKey(d.readInt16())
+	apiVersion = d.readInt16()
+	correlationID = d.readInt32()
+	clientID = d.readString()
+
+	if i := int(apiKey); i < 0 || i >= len(apiTypes) {
+		err = fmt.Errorf("unsupported api key: %d", i)
+		return
+	}
+
+	if err = d.err; err != nil {
+		err = dontExpectEOF(err)
+		return
+	}
+
+	t := &apiTypes[apiKey]
+	if t == nil {
+		err = fmt.Errorf("unsupported api: %s", apiNames[apiKey])
+		return
+	}
+
+	minVersion := t.minVersion()
+	maxVersion := t.maxVersion()
+
+	if apiVersion < minVersion || apiVersion > maxVersion {
+		err = fmt.Errorf("unsupported %s version: v%d not in range v%d-v%d", apiKey, apiVersion, minVersion, maxVersion)
+		return
+	}
+
+	req := &t.requests[apiVersion-minVersion]
+
+	if req.flexible {
+		// In the flexible case, there's a tag buffer at the end of the request header
+		taggedCount := int(d.readUnsignedVarInt())
+		for i := 0; i < taggedCount; i++ {
+			d.readUnsignedVarInt() // tagID
+			size := d.readUnsignedVarInt()
+
+			// Just throw away the values for now
+			d.read(int(size))
+		}
+	}
+
+	msg = req.new()
+	req.decode(d, valueOf(msg))
+	d.discardAll()
+
+	if err = d.err; err != nil {
+		err = dontExpectEOF(err)
+	}
+
+	return
+}
+
+func WriteRequest(w io.Writer, apiVersion int16, correlationID int32, clientID string, msg Message) error {
+	apiKey := msg.ApiKey()
+
+	if i := int(apiKey); i < 0 || i >= len(apiTypes) {
+		return fmt.Errorf("unsupported api key: %d", i)
+	}
+
+	t := &apiTypes[apiKey]
+	if t == nil {
+		return fmt.Errorf("unsupported api: %s", apiNames[apiKey])
+	}
+
+	if typedMessage, ok := msg.(OverrideTypeMessage); ok {
+		typeKey := typedMessage.TypeKey()
+		overrideType := overrideApiTypes[apiKey][typeKey]
+		t = &overrideType
+	}
+
+	minVersion := t.minVersion()
+	maxVersion := t.maxVersion()
+
+	if apiVersion < minVersion || apiVersion > maxVersion {
+		return fmt.Errorf("unsupported %s version: v%d not in range v%d-v%d", apiKey, apiVersion, minVersion, maxVersion)
+	}
+
+	r := &t.requests[apiVersion-minVersion]
+	v := valueOf(msg)
+	b := newPageBuffer()
+	defer b.unref()
+
+	e := &encoder{writer: b}
+	e.writeInt32(0) // placeholder for the request size
+	e.writeInt16(int16(apiKey))
+	e.writeInt16(apiVersion)
+	e.writeInt32(correlationID)
+
+	if r.flexible {
+		// Flexible messages use a nullable string for the client ID, then extra space for a
+		// tag buffer, which begins with a size value. Since we're not writing any fields into the
+		// latter, we can just write zero for now.
+		//
+		// See
+		// https://cwiki.apache.org/confluence/display/KAFKA/KIP-482%3A+The+Kafka+Protocol+should+Support+Optional+Tagged+Fields
+		// for details.
+		e.writeNullString(clientID)
+		e.writeUnsignedVarInt(0)
+	} else {
+		// Technically, recent versions of kafka interpret this field as a nullable
+		// string, however kafka 0.10 expected a non-nullable string and fails with
+		// a NullPointerException when it receives a null client id.
+		e.writeString(clientID)
+	}
+	r.encode(e, v)
+	err := e.err
+
+	if err == nil {
+		size := packUint32(uint32(b.Size()) - 4)
+		b.WriteAt(size[:], 0)
+		_, err = b.WriteTo(w)
+	}
+
+	return err
+}