src/cloud_print/gcp20/prototype/dns_packet_parser.cc

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "cloud_print/gcp20/prototype/dns_packet_parser.h"
   6
   7 #include "net/base/big_endian.h"
   8
   9 DnsPacketParser::DnsPacketParser(const char* packet, size_t length)
  10     : packet_(packet),
  11       length_(length),
  12       record_parser_(packet, length, sizeof(header_)) {
  13   net::BigEndianReader reader(packet, length);
  14   is_header_read_ = reader.ReadU16(&header_.id) &&
  15                     reader.ReadU16(&header_.flags) &&
  16                     reader.ReadU16(&header_.qdcount) &&
  17                     reader.ReadU16(&header_.ancount) &&
  18                     reader.ReadU16(&header_.nscount) &&
  19                     reader.ReadU16(&header_.arcount);
  20 }
  21
  22 bool DnsPacketParser::ReadRecord(DnsQueryRecord* out) {
  23   DCHECK(packet_);
  24   DnsQueryRecord result;
  25   size_t consumed = ReadName(&result.qname);
  26   if (!consumed)
  27     return false;
  28   net::BigEndianReader reader(packet_ + GetOffset() + consumed,
  29                               length_ - (GetOffset() + consumed));
  30   if (reader.ReadU16(&result.qtype) && reader.ReadU16(&result.qclass) &&
  31     record_parser_.SkipQuestion()) {  // instead of |cur_ = reader.ptr();|
  32       *out = result;
  33       return true;
  34   }
  35
  36   return false;
  37 }
  38