Remove old protocol parsing stuff

Author: worryg0d

control.go

@@ -32,7 +32,6 @@ import (
 	"math/rand"
 	"net"
 	"os"
-	"regexp"
 	"strconv"
 	"sync"
 	"sync/atomic"
@@ -202,48 +201,6 @@ func shuffleHosts(hosts []*HostInfo) []*HostInfo {
 	return shuffled
 }
 
-// this is going to be version dependant and a nightmare to maintain :(
-var protocolSupportRe = regexp.MustCompile(`the lowest supported version is \d+ and the greatest is (\d+)$`)
-var betaProtocolRe = regexp.MustCompile(`Beta version of the protocol used \(.*\), but USE_BETA flag is unset`)
-
-func parseProtocolFromError(err error) int {
-	errStr := err.Error()
-
-	var errProtocol ErrProtocol
-	if errors.As(err, &errProtocol) {
-		err = errProtocol.error
-	}
-
-	// I really wish this had the actual info in the error frame...
-	matches := betaProtocolRe.FindAllStringSubmatch(errStr, -1)
-	if len(matches) == 1 {
-		var protoErr *protocolError
-		if errors.As(err, &protoErr) {
-			version := protoErr.frame.Header().version.version()
-			if version > 0 {
-				return int(version - 1)
-			}
-		}
-		return 0
-	}
-
-	matches = protocolSupportRe.FindAllStringSubmatch(errStr, -1)
-	if len(matches) != 1 || len(matches[0]) != 2 {
-		var protoErr *protocolError
-		if errors.As(err, &protoErr) {
-			return int(protoErr.frame.Header().version.version())
-		}
-		return 0
-	}
-
-	max, err := strconv.Atoi(matches[0][1])
-	if err != nil {
-		return 0
-	}
-
-	return max
-}
-
 const highestProtocolVersionSupported = 5
 const lowestProtocolVersionSupported = 3