Cache for mDNS records

net/dns/dns_protocol.h

Index: net/dns/dns_protocol.h
diff --git a/net/dns/dns_protocol.h b/net/dns/dns_protocol.h
index 99563b5b6c50722001e1de62c07d99a451f2e3c0..9b723eaff0047d4dc5d6688c227812983c9aeedd 100644
--- a/net/dns/dns_protocol.h
+++ b/net/dns/dns_protocol.h
@@ -90,6 +90,9 @@ static const uint8 kLabelPointer = 0xc0;
 static const uint8 kLabelDirect = 0x0;
 static const uint16 kOffsetMask = 0x3fff;
 
+// The top bit of the MDns class is the cache flush bit.

[szym, 2013/05/14 18:14:27]

I'm confused by this comment. What is MDns class? What is the cache flush bit?

[Noam Samuel, 2013/05/14 19:28:01]

Sorry about that, the comment is rather vague. I will change it to explain that
it is the top bit of the rrclass and added a reference to
http://www.rfc-editor.org/rfc/rfc6762.txt section 10.2. 

+static const uint16 kMDnsClassMask = 0x7FFF;
+
 static const int kMaxNameLength = 255;
 
 // RFC 1035, section 4.2.1: Messages carried by UDP are restricted to 512
@@ -129,4 +132,3 @@ static const uint16 kFlagAA = 0x400;
 }  // namespace net
 
 #endif  // NET_DNS_DNS_PROTOCOL_H_
-