Implement simple Happy Eyeballs for HTTP/FTP downloads

1 files changed, 140 insertions, 0 deletions

diff --git a/src/BackupIPv4ConnectCommand.cc b/src/BackupIPv4ConnectCommand.cc
new file mode 100644
index 00000000..9ca2081b
--- /dev/null
+++ b/src/BackupIPv4ConnectCommand.cc
@@ -0,0 +1,140 @@
+/* <!-- copyright */
+/*
+ * aria2 - The high speed download utility
+ *
+ * Copyright (C) 2013 Tatsuhiro Tsujikawa
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * In addition, as a special exception, the copyright holders give
+ * permission to link the code of portions of this program with the
+ * OpenSSL library under certain conditions as described in each
+ * individual source file, and distribute linked combinations
+ * including the two.
+ * You must obey the GNU General Public License in all respects
+ * for all of the code used other than OpenSSL.  If you modify
+ * file(s) with this exception, you may extend this exception to your
+ * version of the file(s), but you are not obligated to do so.  If you
+ * do not wish to do so, delete this exception statement from your
+ * version.  If you delete this exception statement from all source
+ * files in the program, then also delete it here.
+ */
+/* copyright --> */
+#include "BackupIPv4ConnectCommand.h"
+#include "RequestGroup.h"
+#include "DownloadEngine.h"
+#include "SocketCore.h"
+#include "wallclock.h"
+#include "RecoverableException.h"
+#include "fmt.h"
+#include "LogFactory.h"
+#include "prefs.h"
+#include "Option.h"
+
+namespace aria2 {
+
+BackupConnectInfo::BackupConnectInfo()
+  : cancel(false)
+{}
+
+BackupIPv4ConnectCommand::BackupIPv4ConnectCommand
+(cuid_t cuid, const std::string& ipaddr, uint16_t port,
+ const SharedHandle<BackupConnectInfo>& info, Command* mainCommand,
+ RequestGroup* requestGroup, DownloadEngine* e)
+: Command(cuid),
+  ipaddr_(ipaddr),
+  port_(port),
+  info_(info),
+  mainCommand_(mainCommand),
+  requestGroup_(requestGroup),
+  e_(e),
+  startTime_(global::wallclock()),
+  timeoutCheck_(global::wallclock()),
+  timeout_(requestGroup_->getOption()->getAsInt(PREF_CONNECT_TIMEOUT))
+{
+  requestGroup_->increaseStreamCommand();
+  requestGroup_->increaseNumCommand();
+}
+
+BackupIPv4ConnectCommand::~BackupIPv4ConnectCommand()
+{
+  requestGroup_->decreaseNumCommand();
+  requestGroup_->decreaseStreamCommand();
+  if(socket_) {
+    e_->deleteSocketForWriteCheck(socket_, this);
+  }
+}
+
+bool BackupIPv4ConnectCommand::execute()
+{
+  bool retval = false;
+  if(requestGroup_->downloadFinished() || requestGroup_->isHaltRequested()) {
+    retval = true;
+  } else if(info_->cancel) {
+    A2_LOG_INFO(fmt("CUID#%"PRId64" - Backup connection canceled", getCuid()));
+    retval = true;
+  } else if(socket_) {
+    if(writeEventEnabled()) {
+      try {
+        std::string error = socket_->getSocketError();
+        if(error.empty()) {
+          A2_LOG_INFO(fmt("CUID#%"PRId64" - Backup connection to %s "
+                          "established", getCuid(), ipaddr_.c_str()));
+          info_->ipaddr = ipaddr_;
+          e_->deleteSocketForWriteCheck(socket_, this);
+          info_->socket.swap(socket_);
+          mainCommand_->setStatus(STATUS_ONESHOT_REALTIME);
+          e_->setNoWait(true);
+          retval = true;
+        } else {
+          A2_LOG_INFO(fmt("CUID#%"PRId64" - Backup connection failed: %s",
+                          getCuid(), error.c_str()));
+          retval = true;
+        }
+      } catch(RecoverableException& e) {
+        A2_LOG_INFO_EX(fmt("CUID#%"PRId64" - Backup connection failed",
+                           getCuid()), e);
+        retval = true;
+      }
+    }
+  } else if(!socket_) {
+    // TODO Although we check 300ms initial timeout as described in
+    // RFC 6555, the interval will be much longer and around 1 second
+    // due to the refresh interval mechanism in DownloadEngine.
+    if(startTime_.differenceInMillis(global::wallclock()) >= 300) {
+      socket_.reset(new SocketCore());
+      try {
+        socket_->establishConnection(ipaddr_, port_);
+        e_->addSocketForWriteCheck(socket_, this);
+        timeoutCheck_ = global::wallclock();
+      } catch(RecoverableException& e) {
+        A2_LOG_INFO_EX(fmt("CUID#%"PRId64" - Backup connection failed",
+                           getCuid()), e);
+        socket_.reset();
+        retval = true;
+      }
+    }
+  } else if(timeoutCheck_.difference(global::wallclock()) >= timeout_) {
+    A2_LOG_INFO(fmt("CUID#%"PRId64" - Backup connection command timeout",
+                    getCuid()));
+    retval = true;
+  }
+  if(!retval) {
+    e_->addCommand(this);
+  }
+  return retval;
+}
+
+} // namespace aria2