ircd/irc/ircconn.go
Shivaram Lingamneni 8cadc7340a don't trim line endings in IRCStreamConn
Doesn't help if the line ends with regular \n only,
and the parser has to account for \r and \n anyway
2020-06-23 03:25:20 -04:00

138 lines
3.2 KiB
Go

package irc
import (
"bufio"
"bytes"
"net"
"unicode/utf8"
"github.com/gorilla/websocket"
"github.com/goshuirc/irc-go/ircmsg"
"github.com/oragono/oragono/irc/utils"
)
const (
maxReadQBytes = ircmsg.MaxlenTagsFromClient + 512 + 1024
)
var (
crlf = []byte{'\r', '\n'}
)
// IRCConn abstracts away the distinction between a regular
// net.Conn (which includes both raw TCP and TLS) and a websocket.
// it doesn't expose the net.Conn, io.Reader, or io.Writer interfaces
// because websockets are message-oriented, not stream-oriented, and
// therefore this abstraction is message-oriented as well.
type IRCConn interface {
UnderlyingConn() *utils.WrappedConn
// these take an IRC line or lines, correctly terminated with CRLF:
WriteLine([]byte) error
WriteLines([][]byte) error
// this returns an IRC line without the terminating CRLF:
ReadLine() (line []byte, err error)
Close() error
}
// IRCStreamConn is an IRCConn over a regular stream connection.
type IRCStreamConn struct {
conn *utils.WrappedConn
reader *bufio.Reader
}
func NewIRCStreamConn(conn *utils.WrappedConn) *IRCStreamConn {
return &IRCStreamConn{
conn: conn,
}
}
func (cc *IRCStreamConn) UnderlyingConn() *utils.WrappedConn {
return cc.conn
}
func (cc *IRCStreamConn) WriteLine(buf []byte) (err error) {
_, err = cc.conn.Write(buf)
return
}
func (cc *IRCStreamConn) WriteLines(buffers [][]byte) (err error) {
// on Linux, with a plaintext TCP or Unix domain socket,
// the Go runtime will optimize this into a single writev(2) call:
_, err = (*net.Buffers)(&buffers).WriteTo(cc.conn)
return
}
func (cc *IRCStreamConn) ReadLine() (line []byte, err error) {
// lazy initialize the reader in case the IP is banned
if cc.reader == nil {
cc.reader = bufio.NewReaderSize(cc.conn, maxReadQBytes)
}
var isPrefix bool
line, isPrefix, err = cc.reader.ReadLine()
if isPrefix {
return nil, errReadQ
}
if globalUtf8EnforcementSetting && !utf8.Valid(line) {
err = errInvalidUtf8
}
return
}
func (cc *IRCStreamConn) Close() (err error) {
return cc.conn.Close()
}
// IRCWSConn is an IRCConn over a websocket.
type IRCWSConn struct {
conn *websocket.Conn
}
func NewIRCWSConn(conn *websocket.Conn) IRCWSConn {
return IRCWSConn{conn: conn}
}
func (wc IRCWSConn) UnderlyingConn() *utils.WrappedConn {
// just assume that the type is OK
wConn, _ := wc.conn.UnderlyingConn().(*utils.WrappedConn)
return wConn
}
func (wc IRCWSConn) WriteLine(buf []byte) (err error) {
buf = bytes.TrimSuffix(buf, crlf)
if !globalUtf8EnforcementSetting && !utf8.Valid(buf) {
// there's not much we can do about this;
// silently drop the message
return nil
}
return wc.conn.WriteMessage(websocket.TextMessage, buf)
}
func (wc IRCWSConn) WriteLines(buffers [][]byte) (err error) {
for _, buf := range buffers {
err = wc.WriteLine(buf)
if err != nil {
return
}
}
return
}
func (wc IRCWSConn) ReadLine() (line []byte, err error) {
for {
var messageType int
messageType, line, err = wc.conn.ReadMessage()
// on empty message or non-text message, try again, block if necessary
if err != nil || (messageType == websocket.TextMessage && len(line) != 0) {
return
}
}
}
func (wc IRCWSConn) Close() (err error) {
return wc.conn.Close()
}