Fast-fail WPAD detection.

net/proxy/proxy_script_decider.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef NET_PROXY_PROXY_SCRIPT_DECIDER_H_
 #define NET_PROXY_PROXY_SCRIPT_DECIDER_H_
 
 #include <string>
 #include <vector>
 
 #include "base/memory/ref_counted.h"
 #include "base/strings/string16.h"
 #include "base/time/time.h"
 #include "base/timer/timer.h"
+#include "net/base/address_list.h"
 #include "net/base/completion_callback.h"
 #include "net/base/net_export.h"
 #include "net/base/net_log.h"
+#include "net/dns/host_resolver.h"
+#include "net/dns/single_request_host_resolver.h"
 #include "net/proxy/proxy_config.h"
 #include "net/proxy/proxy_resolver.h"
 #include "url/gurl.h"
 
 namespace net {
 
 class DhcpProxyScriptFetcher;
 class NetLogParameter;
 class ProxyResolver;
 class ProxyScriptFetcher;
@@ skipping 70 matching lines @@
     Type type;
     GURL url;  // Empty unless |type == PAC_SOURCE_CUSTOM|.
   };
 
   typedef std::vector<PacSource> PacSourceList;
 
   enum State {
     STATE_NONE,
     STATE_WAIT,
     STATE_WAIT_COMPLETE,
+    STATE_QUICK_CHECK,
+    STATE_QUICK_CHECK_COMPLETE,
     STATE_FETCH_PAC_SCRIPT,
     STATE_FETCH_PAC_SCRIPT_COMPLETE,
     STATE_VERIFY_PAC_SCRIPT,
     STATE_VERIFY_PAC_SCRIPT_COMPLETE,
   };
 
   // Returns ordered list of PAC urls to try for |config|.
   PacSourceList BuildPacSourcesFallbackList(const ProxyConfig& config) const;
 
   void OnIOCompletion(int result);
   int DoLoop(int result);
   void DoCallback(int result);
 
   int DoWait();
   int DoWaitComplete(int result);
 
+  int DoQuickCheck();
+  int DoQuickCheckComplete(int result);
+
   int DoFetchPacScript();
   int DoFetchPacScriptComplete(int result);
 
   int DoVerifyPacScript();
   int DoVerifyPacScriptComplete(int result);
 
   // Tries restarting using the next fallback PAC URL:
   // |pac_sources_[++current_pac_source_index]|.
   // Returns OK and rewinds the state machine when there
   // is something to try, otherwise returns |error|.
@@ skipping 20 matching lines @@
 
   size_t current_pac_source_index_;
 
   // Filled when the PAC script fetch completes.
   base::string16 pac_script_;
 
   // Flag indicating whether the caller requested a mandatory pac script
   // (i.e. fallback to direct connections are prohibited).
   bool pac_mandatory_;
 
+  // Whether we have an existing custom PAC URL.
+  bool have_custom_pac_url_;
+
   PacSourceList pac_sources_;
   State next_state_;
 
   BoundNetLog net_log_;
 
   bool fetch_pac_bytes_;
 
   base::TimeDelta wait_delay_;
   base::OneShotTimer<ProxyScriptDecider> wait_timer_;
 
   // Results.
   ProxyConfig effective_config_;
   scoped_refptr<ProxyResolverScriptData> script_data_;
 
+  AddressList wpad_addresses_;
+  base::OneShotTimer<ProxyScriptDecider> quick_check_timer_;
+  scoped_ptr<SingleRequestHostResolver> host_resolver_;
+  base::Time quick_check_start_time_;
 
   DISALLOW_COPY_AND_ASSIGN(ProxyScriptDecider);
 };
 
 }  // namespace net
 
 #endif  // NET_PROXY_PROXY_SCRIPT_DECIDER_H_