Paul Stewart | e692740 | 2012-01-23 16:11:30 -0800 | [diff] [blame] | 1 | // Copyright (c) 2012 The Chromium OS Authors. All rights reserved. |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 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 "shill/dns_client.h" |
| 6 | |
| 7 | #include <arpa/inet.h> |
| 8 | #include <netdb.h> |
| 9 | #include <netinet/in.h> |
| 10 | #include <sys/socket.h> |
| 11 | |
| 12 | #include <map> |
| 13 | #include <set> |
| 14 | #include <string> |
| 15 | #include <tr1/memory> |
| 16 | #include <vector> |
| 17 | |
Eric Shienbrood | 3e20a23 | 2012-02-16 11:35:56 -0500 | [diff] [blame] | 18 | #include <base/bind.h> |
| 19 | #include <base/bind_helpers.h> |
| 20 | #include <base/stl_util.h> |
Paul Stewart | bdb02e6 | 2012-02-22 16:24:33 -0800 | [diff] [blame] | 21 | #include <base/string_number_conversions.h> |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 22 | |
Christopher Wiley | b691efd | 2012-08-09 13:51:51 -0700 | [diff] [blame] | 23 | #include "shill/logging.h" |
Darin Petkov | 89593a9 | 2012-02-21 10:59:48 +0100 | [diff] [blame] | 24 | #include "shill/shill_ares.h" |
| 25 | #include "shill/shill_time.h" |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 26 | |
Eric Shienbrood | 3e20a23 | 2012-02-16 11:35:56 -0500 | [diff] [blame] | 27 | using base::Bind; |
| 28 | using base::Unretained; |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 29 | using std::map; |
| 30 | using std::set; |
| 31 | using std::string; |
| 32 | using std::vector; |
| 33 | |
| 34 | namespace shill { |
| 35 | |
| 36 | const int DNSClient::kDefaultTimeoutMS = 2000; |
| 37 | const char DNSClient::kErrorNoData[] = "The query response contains no answers"; |
| 38 | const char DNSClient::kErrorFormErr[] = "The server says the query is bad"; |
| 39 | const char DNSClient::kErrorServerFail[] = "The server says it had a failure"; |
| 40 | const char DNSClient::kErrorNotFound[] = "The queried-for domain was not found"; |
| 41 | const char DNSClient::kErrorNotImp[] = "The server doesn't implement operation"; |
| 42 | const char DNSClient::kErrorRefused[] = "The server replied, refused the query"; |
| 43 | const char DNSClient::kErrorBadQuery[] = "Locally we could not format a query"; |
| 44 | const char DNSClient::kErrorNetRefused[] = "The network connection was refused"; |
| 45 | const char DNSClient::kErrorTimedOut[] = "The network connection was timed out"; |
| 46 | const char DNSClient::kErrorUnknown[] = "DNS Resolver unknown internal error"; |
| 47 | |
| 48 | // Private to the implementation of resolver so callers don't include ares.h |
| 49 | struct DNSClientState { |
Darin Petkov | e636c69 | 2012-05-31 10:22:17 +0200 | [diff] [blame] | 50 | DNSClientState() : channel(NULL), start_time((struct timeval){0}) {} |
| 51 | |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 52 | ares_channel channel; |
| 53 | map< ares_socket_t, std::tr1::shared_ptr<IOHandler> > read_handlers; |
| 54 | map< ares_socket_t, std::tr1::shared_ptr<IOHandler> > write_handlers; |
Darin Petkov | e636c69 | 2012-05-31 10:22:17 +0200 | [diff] [blame] | 55 | struct timeval start_time; |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 56 | }; |
| 57 | |
| 58 | DNSClient::DNSClient(IPAddress::Family family, |
| 59 | const string &interface_name, |
| 60 | const vector<string> &dns_servers, |
| 61 | int timeout_ms, |
| 62 | EventDispatcher *dispatcher, |
Eric Shienbrood | 3e20a23 | 2012-02-16 11:35:56 -0500 | [diff] [blame] | 63 | const ClientCallback &callback) |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 64 | : address_(IPAddress(family)), |
| 65 | interface_name_(interface_name), |
| 66 | dns_servers_(dns_servers), |
| 67 | dispatcher_(dispatcher), |
| 68 | callback_(callback), |
| 69 | timeout_ms_(timeout_ms), |
| 70 | running_(false), |
| 71 | resolver_state_(NULL), |
Eric Shienbrood | 3e20a23 | 2012-02-16 11:35:56 -0500 | [diff] [blame] | 72 | weak_ptr_factory_(this), |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 73 | ares_(Ares::GetInstance()), |
| 74 | time_(Time::GetInstance()) {} |
| 75 | |
| 76 | DNSClient::~DNSClient() { |
| 77 | Stop(); |
| 78 | } |
| 79 | |
Paul Stewart | bdb02e6 | 2012-02-22 16:24:33 -0800 | [diff] [blame] | 80 | bool DNSClient::Start(const string &hostname, Error *error) { |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 81 | if (running_) { |
Paul Stewart | bdb02e6 | 2012-02-22 16:24:33 -0800 | [diff] [blame] | 82 | Error::PopulateAndLog(error, Error::kInProgress, |
| 83 | "Only one DNS request is allowed at a time"); |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 84 | return false; |
| 85 | } |
| 86 | |
| 87 | if (!resolver_state_.get()) { |
| 88 | struct ares_options options; |
| 89 | memset(&options, 0, sizeof(options)); |
| 90 | |
| 91 | vector<struct in_addr> server_addresses; |
| 92 | for (vector<string>::iterator it = dns_servers_.begin(); |
| 93 | it != dns_servers_.end(); |
| 94 | ++it) { |
| 95 | struct in_addr addr; |
| 96 | if (inet_aton(it->c_str(), &addr) != 0) { |
| 97 | server_addresses.push_back(addr); |
| 98 | } |
| 99 | } |
| 100 | |
| 101 | if (server_addresses.empty()) { |
Paul Stewart | bdb02e6 | 2012-02-22 16:24:33 -0800 | [diff] [blame] | 102 | Error::PopulateAndLog(error, Error::kInvalidArguments, |
| 103 | "No valid DNS server addresses"); |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 104 | return false; |
| 105 | } |
| 106 | |
| 107 | options.servers = server_addresses.data(); |
| 108 | options.nservers = server_addresses.size(); |
| 109 | options.timeout = timeout_ms_; |
| 110 | |
| 111 | resolver_state_.reset(new DNSClientState); |
| 112 | int status = ares_->InitOptions(&resolver_state_->channel, |
| 113 | &options, |
| 114 | ARES_OPT_SERVERS | ARES_OPT_TIMEOUTMS); |
| 115 | if (status != ARES_SUCCESS) { |
Paul Stewart | bdb02e6 | 2012-02-22 16:24:33 -0800 | [diff] [blame] | 116 | Error::PopulateAndLog(error, Error::kOperationFailed, |
| 117 | "ARES initialization returns error code: " + |
| 118 | base::IntToString(status)); |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 119 | resolver_state_.reset(); |
| 120 | return false; |
| 121 | } |
| 122 | |
| 123 | ares_->SetLocalDev(resolver_state_->channel, interface_name_.c_str()); |
| 124 | } |
| 125 | |
| 126 | running_ = true; |
Darin Petkov | e636c69 | 2012-05-31 10:22:17 +0200 | [diff] [blame] | 127 | time_->GetTimeMonotonic(&resolver_state_->start_time); |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 128 | ares_->GetHostByName(resolver_state_->channel, hostname.c_str(), |
| 129 | address_.family(), ReceiveDNSReplyCB, this); |
| 130 | |
| 131 | if (!RefreshHandles()) { |
| 132 | LOG(ERROR) << "Impossibly short timeout."; |
Paul Stewart | bdb02e6 | 2012-02-22 16:24:33 -0800 | [diff] [blame] | 133 | error->CopyFrom(error_); |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 134 | Stop(); |
| 135 | return false; |
| 136 | } |
| 137 | |
| 138 | return true; |
| 139 | } |
| 140 | |
| 141 | void DNSClient::Stop() { |
Ben Chan | fad4a0b | 2012-04-18 15:49:59 -0700 | [diff] [blame] | 142 | SLOG(DNS, 3) << "In " << __func__; |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 143 | if (!resolver_state_.get()) { |
| 144 | return; |
| 145 | } |
| 146 | |
| 147 | running_ = false; |
Eric Shienbrood | 3e20a23 | 2012-02-16 11:35:56 -0500 | [diff] [blame] | 148 | weak_ptr_factory_.InvalidateWeakPtrs(); |
Paul Stewart | bdb02e6 | 2012-02-22 16:24:33 -0800 | [diff] [blame] | 149 | error_.Reset(); |
| 150 | address_.SetAddressToDefault(); |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 151 | ares_->Destroy(resolver_state_->channel); |
| 152 | resolver_state_.reset(); |
| 153 | } |
| 154 | |
Paul Stewart | bdb02e6 | 2012-02-22 16:24:33 -0800 | [diff] [blame] | 155 | // We delay our call to completion so that we exit all IOHandlers, and |
| 156 | // can clean up all of our local state before calling the callback, or |
| 157 | // during the process of the execution of the callee (which is free to |
| 158 | // call our destructor safely). |
| 159 | void DNSClient::HandleCompletion() { |
Ben Chan | fad4a0b | 2012-04-18 15:49:59 -0700 | [diff] [blame] | 160 | SLOG(DNS, 3) << "In " << __func__; |
Paul Stewart | bdb02e6 | 2012-02-22 16:24:33 -0800 | [diff] [blame] | 161 | Error error; |
| 162 | error.CopyFrom(error_); |
| 163 | IPAddress address(address_); |
| 164 | if (!error.IsSuccess()) { |
| 165 | // If the DNS request did not succeed, do not trust it for future |
| 166 | // attempts. |
| 167 | Stop(); |
| 168 | } else { |
| 169 | // Prepare our state for the next request without destroying the |
| 170 | // current ARES state. |
| 171 | error_.Reset(); |
| 172 | address_.SetAddressToDefault(); |
| 173 | } |
Eric Shienbrood | 3e20a23 | 2012-02-16 11:35:56 -0500 | [diff] [blame] | 174 | callback_.Run(error, address); |
Paul Stewart | bdb02e6 | 2012-02-22 16:24:33 -0800 | [diff] [blame] | 175 | } |
| 176 | |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 177 | void DNSClient::HandleDNSRead(int fd) { |
| 178 | ares_->ProcessFd(resolver_state_->channel, fd, ARES_SOCKET_BAD); |
| 179 | RefreshHandles(); |
| 180 | } |
| 181 | |
| 182 | void DNSClient::HandleDNSWrite(int fd) { |
| 183 | ares_->ProcessFd(resolver_state_->channel, ARES_SOCKET_BAD, fd); |
| 184 | RefreshHandles(); |
| 185 | } |
| 186 | |
| 187 | void DNSClient::HandleTimeout() { |
| 188 | ares_->ProcessFd(resolver_state_->channel, ARES_SOCKET_BAD, ARES_SOCKET_BAD); |
Paul Stewart | bdb02e6 | 2012-02-22 16:24:33 -0800 | [diff] [blame] | 189 | RefreshHandles(); |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 190 | } |
| 191 | |
| 192 | void DNSClient::ReceiveDNSReply(int status, struct hostent *hostent) { |
| 193 | if (!running_) { |
| 194 | // We can be called during ARES shutdown -- ignore these events. |
| 195 | return; |
| 196 | } |
Ben Chan | fad4a0b | 2012-04-18 15:49:59 -0700 | [diff] [blame] | 197 | SLOG(DNS, 3) << "In " << __func__; |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 198 | running_ = false; |
Paul Stewart | f582b50 | 2012-04-04 21:39:22 -0700 | [diff] [blame] | 199 | timeout_closure_.Cancel(); |
Eric Shienbrood | 3e20a23 | 2012-02-16 11:35:56 -0500 | [diff] [blame] | 200 | dispatcher_->PostTask(Bind(&DNSClient::HandleCompletion, |
| 201 | weak_ptr_factory_.GetWeakPtr())); |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 202 | |
| 203 | if (status == ARES_SUCCESS && |
| 204 | hostent != NULL && |
| 205 | hostent->h_addrtype == address_.family() && |
Eric Shienbrood | c74cf9c | 2012-03-02 15:00:35 -0500 | [diff] [blame] | 206 | static_cast<size_t>(hostent->h_length) == |
| 207 | IPAddress::GetAddressLength(address_.family()) && |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 208 | hostent->h_addr_list != NULL && |
| 209 | hostent->h_addr_list[0] != NULL) { |
| 210 | address_ = IPAddress(address_.family(), |
| 211 | ByteString(reinterpret_cast<unsigned char *>( |
| 212 | hostent->h_addr_list[0]), hostent->h_length)); |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 213 | } else { |
| 214 | switch (status) { |
| 215 | case ARES_ENODATA: |
Paul Stewart | bdb02e6 | 2012-02-22 16:24:33 -0800 | [diff] [blame] | 216 | error_.Populate(Error::kOperationFailed, kErrorNoData); |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 217 | break; |
| 218 | case ARES_EFORMERR: |
Paul Stewart | bdb02e6 | 2012-02-22 16:24:33 -0800 | [diff] [blame] | 219 | error_.Populate(Error::kOperationFailed, kErrorFormErr); |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 220 | break; |
| 221 | case ARES_ESERVFAIL: |
Paul Stewart | bdb02e6 | 2012-02-22 16:24:33 -0800 | [diff] [blame] | 222 | error_.Populate(Error::kOperationFailed, kErrorServerFail); |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 223 | break; |
| 224 | case ARES_ENOTFOUND: |
Paul Stewart | bdb02e6 | 2012-02-22 16:24:33 -0800 | [diff] [blame] | 225 | error_.Populate(Error::kOperationFailed, kErrorNotFound); |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 226 | break; |
| 227 | case ARES_ENOTIMP: |
Paul Stewart | bdb02e6 | 2012-02-22 16:24:33 -0800 | [diff] [blame] | 228 | error_.Populate(Error::kOperationFailed, kErrorNotImp); |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 229 | break; |
| 230 | case ARES_EREFUSED: |
Paul Stewart | bdb02e6 | 2012-02-22 16:24:33 -0800 | [diff] [blame] | 231 | error_.Populate(Error::kOperationFailed, kErrorRefused); |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 232 | break; |
| 233 | case ARES_EBADQUERY: |
| 234 | case ARES_EBADNAME: |
| 235 | case ARES_EBADFAMILY: |
| 236 | case ARES_EBADRESP: |
Paul Stewart | bdb02e6 | 2012-02-22 16:24:33 -0800 | [diff] [blame] | 237 | error_.Populate(Error::kOperationFailed, kErrorBadQuery); |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 238 | break; |
| 239 | case ARES_ECONNREFUSED: |
Paul Stewart | bdb02e6 | 2012-02-22 16:24:33 -0800 | [diff] [blame] | 240 | error_.Populate(Error::kOperationFailed, kErrorNetRefused); |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 241 | break; |
| 242 | case ARES_ETIMEOUT: |
Paul Stewart | bdb02e6 | 2012-02-22 16:24:33 -0800 | [diff] [blame] | 243 | error_.Populate(Error::kOperationTimeout, kErrorTimedOut); |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 244 | break; |
| 245 | default: |
Paul Stewart | bdb02e6 | 2012-02-22 16:24:33 -0800 | [diff] [blame] | 246 | error_.Populate(Error::kOperationFailed, kErrorUnknown); |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 247 | if (status == ARES_SUCCESS) { |
| 248 | LOG(ERROR) << "ARES returned success but hostent was invalid!"; |
| 249 | } else { |
| 250 | LOG(ERROR) << "ARES returned unhandled error status " << status; |
| 251 | } |
| 252 | break; |
| 253 | } |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 254 | } |
| 255 | } |
| 256 | |
| 257 | void DNSClient::ReceiveDNSReplyCB(void *arg, int status, |
| 258 | int /*timeouts*/, |
| 259 | struct hostent *hostent) { |
| 260 | DNSClient *res = static_cast<DNSClient *>(arg); |
| 261 | res->ReceiveDNSReply(status, hostent); |
| 262 | } |
| 263 | |
| 264 | bool DNSClient::RefreshHandles() { |
| 265 | map< ares_socket_t, std::tr1::shared_ptr<IOHandler> > old_read = |
| 266 | resolver_state_->read_handlers; |
| 267 | map< ares_socket_t, std::tr1::shared_ptr<IOHandler> > old_write = |
| 268 | resolver_state_->write_handlers; |
| 269 | |
| 270 | resolver_state_->read_handlers.clear(); |
| 271 | resolver_state_->write_handlers.clear(); |
| 272 | |
| 273 | ares_socket_t sockets[ARES_GETSOCK_MAXNUM]; |
| 274 | int action_bits = ares_->GetSock(resolver_state_->channel, sockets, |
Paul Stewart | bdb02e6 | 2012-02-22 16:24:33 -0800 | [diff] [blame] | 275 | ARES_GETSOCK_MAXNUM); |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 276 | |
Paul Stewart | f582b50 | 2012-04-04 21:39:22 -0700 | [diff] [blame] | 277 | base::Callback<void(int)> read_callback( |
| 278 | Bind(&DNSClient::HandleDNSRead, weak_ptr_factory_.GetWeakPtr())); |
| 279 | base::Callback<void(int)> write_callback( |
| 280 | Bind(&DNSClient::HandleDNSWrite, weak_ptr_factory_.GetWeakPtr())); |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 281 | for (int i = 0; i < ARES_GETSOCK_MAXNUM; i++) { |
| 282 | if (ARES_GETSOCK_READABLE(action_bits, i)) { |
| 283 | if (ContainsKey(old_read, sockets[i])) { |
| 284 | resolver_state_->read_handlers[sockets[i]] = old_read[sockets[i]]; |
| 285 | } else { |
| 286 | resolver_state_->read_handlers[sockets[i]] = |
| 287 | std::tr1::shared_ptr<IOHandler> ( |
| 288 | dispatcher_->CreateReadyHandler(sockets[i], |
| 289 | IOHandler::kModeInput, |
Paul Stewart | f582b50 | 2012-04-04 21:39:22 -0700 | [diff] [blame] | 290 | read_callback)); |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 291 | } |
| 292 | } |
| 293 | if (ARES_GETSOCK_WRITABLE(action_bits, i)) { |
| 294 | if (ContainsKey(old_write, sockets[i])) { |
| 295 | resolver_state_->write_handlers[sockets[i]] = old_write[sockets[i]]; |
| 296 | } else { |
| 297 | resolver_state_->write_handlers[sockets[i]] = |
| 298 | std::tr1::shared_ptr<IOHandler> ( |
| 299 | dispatcher_->CreateReadyHandler(sockets[i], |
| 300 | IOHandler::kModeOutput, |
Paul Stewart | f582b50 | 2012-04-04 21:39:22 -0700 | [diff] [blame] | 301 | write_callback)); |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 302 | } |
| 303 | } |
| 304 | } |
| 305 | |
| 306 | if (!running_) { |
Paul Stewart | bdb02e6 | 2012-02-22 16:24:33 -0800 | [diff] [blame] | 307 | // We are here just to clean up socket handles, and the ARES state was |
| 308 | // cleaned up during the last call to ares_->ProcessFd(). |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 309 | return false; |
| 310 | } |
| 311 | |
| 312 | // Schedule timer event for the earlier of our timeout or one requested by |
| 313 | // the resolver library. |
| 314 | struct timeval now, elapsed_time, timeout_tv; |
Paul Stewart | e692740 | 2012-01-23 16:11:30 -0800 | [diff] [blame] | 315 | time_->GetTimeMonotonic(&now); |
Darin Petkov | e636c69 | 2012-05-31 10:22:17 +0200 | [diff] [blame] | 316 | timersub(&now, &resolver_state_->start_time, &elapsed_time); |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 317 | timeout_tv.tv_sec = timeout_ms_ / 1000; |
| 318 | timeout_tv.tv_usec = (timeout_ms_ % 1000) * 1000; |
Paul Stewart | f582b50 | 2012-04-04 21:39:22 -0700 | [diff] [blame] | 319 | timeout_closure_.Cancel(); |
Paul Stewart | bdb02e6 | 2012-02-22 16:24:33 -0800 | [diff] [blame] | 320 | |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 321 | if (timercmp(&elapsed_time, &timeout_tv, >=)) { |
| 322 | // There are 3 cases of interest: |
Paul Stewart | bdb02e6 | 2012-02-22 16:24:33 -0800 | [diff] [blame] | 323 | // - If we got here from Start(), when we return, Stop() will be |
| 324 | // called, so our cleanup task will not run, so we will not have the |
| 325 | // side-effect of both invoking the callback and returning False |
| 326 | // in Start(). |
| 327 | // - If we got here from the tail of an IO event, we can't call |
| 328 | // Stop() since that will blow away the IOHandler we are running |
| 329 | // in. We will perform the cleanup in the posted task below. |
| 330 | // - If we got here from a timeout handler, we will perform cleanup |
| 331 | // in the posted task. |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 332 | running_ = false; |
Paul Stewart | bdb02e6 | 2012-02-22 16:24:33 -0800 | [diff] [blame] | 333 | error_.Populate(Error::kOperationTimeout, kErrorTimedOut); |
Eric Shienbrood | 3e20a23 | 2012-02-16 11:35:56 -0500 | [diff] [blame] | 334 | dispatcher_->PostTask(Bind(&DNSClient::HandleCompletion, |
| 335 | weak_ptr_factory_.GetWeakPtr())); |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 336 | return false; |
| 337 | } else { |
| 338 | struct timeval max, ret_tv; |
| 339 | timersub(&timeout_tv, &elapsed_time, &max); |
| 340 | struct timeval *tv = ares_->Timeout(resolver_state_->channel, |
| 341 | &max, &ret_tv); |
Paul Stewart | f582b50 | 2012-04-04 21:39:22 -0700 | [diff] [blame] | 342 | timeout_closure_.Reset( |
| 343 | Bind(&DNSClient::HandleTimeout, weak_ptr_factory_.GetWeakPtr())); |
| 344 | dispatcher_->PostDelayedTask(timeout_closure_.callback(), |
| 345 | tv->tv_sec * 1000 + tv->tv_usec / 1000); |
Paul Stewart | c2350ee | 2011-10-19 12:28:40 -0700 | [diff] [blame] | 346 | } |
| 347 | |
| 348 | return true; |
| 349 | } |
| 350 | |
| 351 | } // namespace shill |