update 100-continue logic to support different header placement

proto/proto.go

@@ -144,12 +144,12 @@ func header(payload []byte, name []byte) (value []byte, headerStart, headerEnd,
 	valueEnd = valueStart + bytes.IndexByte(payload[valueStart:], '\n')
 
 	if payload[headerEnd-1] == '\r' {
-		valueEnd -= 1
+		valueEnd--
 	}
 
 	for valueStart < valueEnd  {	// ignore empty space at end of header value
 		if payload[valueEnd-1] == ' ' {
-			valueEnd -= 1
+			valueEnd--
 		} else {
 			break
 		}

raw_socket_listener/listener.go

@@ -28,6 +28,7 @@ import (
 	"strings"
 	"sync"
 	"time"
+	"github.com/buger/gor/proto"
 )
 
 var _ = fmt.Println
@@ -515,8 +516,10 @@ func (t *Listener) isValidPacket(buf []byte) bool {
 	return false
 }
 
-var bExpect100ContinueCheck = []byte("Expect: 100-continue")
+var bExpectHeader = []byte("Expect:")
+var bExpect100Value = []byte("100-continue")
 var bPOST = []byte("POST")
+var bCRLFx2 = []byte("\r\n\r\n")
 
 // Trying to add packet to existing message or creating new message
 //
@@ -590,33 +593,36 @@ func (t *Listener) processTCPPacket(packet *TCPPacket) {
 
 	// Handling Expect: 100-continue requests
 	if len(packet.Data) > 4 && bytes.Equal(packet.Data[0:4], bPOST) {
-		// reading last 20 bytes (not counting CRLF): last header value (if no body presented)
-		if bytes.Equal(packet.Data[len(packet.Data)-24:len(packet.Data)-4], bExpect100ContinueCheck) {
-			seq := packet.Seq + uint32(len(packet.Data))
-			t.seqWithData[seq] = packet.Ack
-			message.DataSeq = seq
+		// reading last 8 bytes for double CRLF
+		if bytes.Equal(packet.Data[len(packet.Data)-4:], bCRLFx2) {
+			// look for an expect:100-continue header
+			if bytes.Equal(bExpect100Value, proto.Header(packet.Data, bExpectHeader)) {
+				seq := packet.Seq + uint32(len(packet.Data))
+				t.seqWithData[seq] = packet.Ack
+				message.DataSeq = seq
 
-			// In case if sequence packet came first
-			for _, m := range t.messages {
-				if m.Seq == seq {
-					t.deleteMessage(m)
-					if m.AssocMessage != nil {
-						message.AssocMessage = m.AssocMessage
-					}
-					// log.Println("2: Adding ack alias:", m.Ack, packet.Ack)
-					t.ackAliases[m.Ack] = packet.Ack
+				// In case if sequence packet came first
+				for _, m := range t.messages {
+					if m.Seq == seq {
+						t.deleteMessage(m)
+						if m.AssocMessage != nil {
+							message.AssocMessage = m.AssocMessage
+						}
+						// log.Println("2: Adding ack alias:", m.Ack, packet.Ack)
+						t.ackAliases[m.Ack] = packet.Ack
 
-					for _, pkt := range m.packets {
-						pkt.UpdateAck(packet.Ack)
-						message.AddPacket(pkt)
+						for _, pkt := range m.packets {
+							pkt.UpdateAck(packet.Ack)
+							message.AddPacket(pkt)
+						}
 					}
 				}
+
+				// Removing `Expect: 100-continue` header
+				packet.Data = proto.DelHeader(packet.Data, bExpectHeader)
+
+				// log.Println(string(packet.Data))
 			}
-
-			// Removing `Expect: 100-continue` header
-			packet.Data = append(packet.Data[:len(packet.Data)-24], packet.Data[len(packet.Data)-2:]...)
-
-			// log.Println(string(packet.Data))
 		}
 	}