Last few fixes and remove debugging prints

This commit is contained in:
Miek Gieben 2012-01-10 08:55:55 +01:00
parent cedf11f27b
commit 28f5e6c1ed
2 changed files with 19 additions and 23 deletions

View File

@ -38,7 +38,7 @@ func main() {
} }
println(r.String()) println(r.String())
buf, _ := r.Pack() buf, _ := r.Pack()
dns.Compress(buf) buf = dns.Compress(buf)
r1 := new(dns.Msg) r1 := new(dns.Msg)
ok := r1.Unpack(buf) ok := r1.Unpack(buf)
if ok { if ok {

View File

@ -4,10 +4,6 @@
package dns package dns
import (
"fmt"
)
const maxPointer = 2 << 13 // We have 14 bits for the offset const maxPointer = 2 << 13 // We have 14 bits for the offset
// Function defined in this subpackage work on []byte and but still // Function defined in this subpackage work on []byte and but still
@ -31,8 +27,8 @@ type rawmove struct {
} }
// Compress performs name comression in the dns message contained in buf. // Compress performs name comression in the dns message contained in buf.
// It returns the number of bytes saved. // It returns the shortened buffer.
func Compress(msg []byte) int { func Compress(msg []byte) []byte {
// First we create a table of domain names to which we // First we create a table of domain names to which we
// can link. This is stored in 'table' // can link. This is stored in 'table'
@ -80,7 +76,7 @@ Loop:
// Discount for previous moves, decrease the poffset counter // Discount for previous moves, decrease the poffset counter
// with moves that occur before it // with moves that occur before it
for i := len(moves)-1; i >= 0; i-- { for i := len(moves) - 1; i >= 0; i-- {
if poffset > moves[i].from { if poffset > moves[i].from {
poffset -= (moves[i].length - 2) poffset -= (moves[i].length - 2)
} }
@ -132,14 +128,14 @@ Loop:
saved := 0 saved := 0
// Start at the back, easier to move // Start at the back, easier to move
for i := len(moves) - 1; i >= 0; i-- { for i := len(moves) - 1; i >= 0; i-- {
fmt.Printf("%v\n", moves[i]) // fmt.Printf("%v\n", moves[i])
// move the bytes // move the bytes
copy(msg[moves[i].from+1:], msg[moves[i].from+moves[i].length-1:]) copy(msg[moves[i].from+1:], msg[moves[i].from+moves[i].length-1:])
// Now set the pointer at moves[i].from and moves[i].from+1 // Now set the pointer at moves[i].from and moves[i].from+1
fmt.Printf("bits %b\n", moves[i].offset^0xC000) // fmt.Printf("bits %b\n", moves[i].offset^0xC000)
msg[moves[i].from], msg[moves[i].from+1] = packUint16(uint16(moves[i].offset ^ 0xC000)) msg[moves[i].from], msg[moves[i].from+1] = packUint16(uint16(moves[i].offset ^ 0xC000))
saved += moves[i].length // minus something saved += (moves[i].length - 2) // minus something
} }
msg = msg[:len(msg) - saved] msg = msg[:len(msg)-saved]
return saved return msg
} }