discard skipped entities

bit/reader.go

@@ -49,6 +49,11 @@ func (r *Reader) ReadBits(bits uint) (n uint64) {
 	return
 }
 
+// discards up to bits bits. returns a bool indicating wheter any errors occured.
+func (r *Reader) DiscardBits(n int) {
+	r.ReadBits(uint(n))
+}
+
 // ReadByte reads a single byte, regardless of alignment.
 func (r *Reader) ReadByte() (byte, error) {
 	if r.bits == 0 {
@@ -73,6 +78,17 @@ func (r *Reader) Read(buf []byte) (int, error) {
 	return len(buf), nil
 }
 
+// discards N byte of data on the reader or until EOF
+func (r *Reader) DiscardBytes(n int) {
+	for i := 0; i < n; i++ {
+		_, err := r.ReadByte()
+		if err != nil {
+			r.err = err
+			return
+		}
+	}
+}
+
 // ReadUbitVar reads a prefixed uint value. A prefix is 2 bits wide, followed
 // by the 4 least-significant bits, then a variable number of most-significant
 // bits based on the prefix.

main.go

@@ -9,7 +9,7 @@ import (
 	"fmt"
 	"io"
 	"os"
-	"reflect"
+	// "reflect"
 	"runtime/pprof"
 	"strings"
 )
@@ -123,12 +123,15 @@ func main() {
 
 	c := make(chan maybe, 32)
 	p := newParser(r)
+	delete(p.ewl, EBaseGameEvents_GE_SosStartSoundEvent)
+	delete(p.ewl, EDotaUserMessages_DOTA_UM_SpectatorPlayerUnitOrders)
+	delete(p.ewl, EDotaUserMessages_DOTA_UM_SpectatorPlayerClick)
 	go p.run(c)
 	for m := range c {
 		if m.error != nil {
 			fmt.Fprintln(os.Stderr, m.error)
 		} else {
-			fmt.Println(reflect.TypeOf(m.Message))
+			// fmt.Println(reflect.TypeOf(m.Message))
 		}
 	}
 	if p.err != nil {

parser.go

@@ -72,8 +72,13 @@ func (p *parser) emitChildren(pkt *dota.CDemoPacket, c chan maybe) {
 	for {
 		t := entityType(br.ReadUBitVar())
 		s := br.ReadVarInt()
-		b := p.scratch[:s]
-		br.Read(b)
+
+		if p.ewl[t] {
+			br.Read(p.scratch[:s])
+		} else {
+			br.DiscardBytes(int(s))
+			continue
+		}
 
 		switch err := br.Err(); err {
 		case nil:
@@ -85,14 +90,10 @@ func (p *parser) emitChildren(pkt *dota.CDemoPacket, c chan maybe) {
 			return
 		}
 
-		if !p.ewl[t] {
-			continue
-		}
-
-		p.pbuf.SetBuf(b)
+		p.pbuf.SetBuf(p.scratch[:s])
 		e, err := messages.BuildEntity(t)
 		if err != nil {
-			c <- maybe{error: wrap(err, "skipping entity of size %d, type %s", len(b), t)}
+			c <- maybe{error: wrap(err, "skipping entity of size %d, type %s", s, t)}
 			continue
 		}
 		if err := p.pbuf.Unmarshal(e); err != nil {