Get rid of synchronous ResolveProxy API.

net/proxy/proxy_service.h

 // Copyright (c) 2006-2008 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_SERVICE_H_
 #define NET_PROXY_PROXY_SERVICE_H_
 
 #include <map>
 #include <vector>
 
 #include "base/ref_counted.h"
 #include "base/scoped_ptr.h"
 #include "base/string_util.h"
 #include "base/thread.h"
 #include "base/time.h"
+#include "base/waitable_event.h"
 #include "googleurl/src/gurl.h"
 #include "net/base/completion_callback.h"
 
-#if defined(OS_WIN)
-typedef LPVOID HINTERNET;  // From winhttp.h
-#endif
-
 class GURL;
 
 namespace net {
 
 class ProxyConfigService;
 class ProxyInfo;
 class ProxyResolver;
 
 // Proxy configuration used to by the ProxyService.
 class ProxyConfig {
@@ skipping 53 matching lines @@
 // resolution.  See ProxyResolverWinHttp for example.
 class ProxyService {
  public:
   // The instance takes ownership of |config_service| and |resolver|.
   ProxyService(ProxyConfigService* config_service,
                ProxyResolver* resolver);
 
   // Used internally to handle PAC queries.
   class PacRequest;
 
-  // Returns OK if proxy information could be provided synchronously.  Else,
-  // ERR_IO_PENDING is returned to indicate that the result will be available
-  // when the callback is run.  The callback is run on the thread that calls
+  // Returns ERR_IO_PENDING if the proxy information could not be provided

[wtc, 2009/01/30 23:06:06]

Ah, so this block comment still needs to be updated.
I missed it this morning.

Since ResolveProxy doesn't have a sync mode any more,
if seems that we should say this instead:
  Returns ERR_IO_PENDING if we have initiated
  asynchronous proxy resolution successfully.  

+  // synchronously, to indicate that the result will be available when the
+  // callback is run.  The callback is run on the thread that calls
   // ResolveProxy.
   //
   // The caller is responsible for ensuring that |results| and |callback|
   // remain valid until the callback is run or until |pac_request| is cancelled
   // via CancelPacRequest.  |pac_request| is only valid while the completion
   // callback is still pending. NULL can be passed for |pac_request| if
   // the caller will not need to cancel the request.
   //
   // We use the three possible proxy access types in the following order, and
   // we only use one of them (no falling back to other access types if the
@@ skipping 129 matching lines @@
   // Use the same proxy server as the given |proxy_info|.
   void Use(const ProxyInfo& proxy_info);
 
   // Use a direct connection.
   void UseDirect();
 
   // Use a specific proxy server, of the form:  <hostname> [":" <port>]
   // This may optionally be a semi-colon delimited list of proxy servers.
   void UseNamedProxy(const std::string& proxy_server);
 
-#if defined(OS_WIN)
-  // Apply this proxy information to the given WinHTTP request handle.
-  void Apply(HINTERNET request_handle);
-#endif
-
   // Returns true if this proxy info specifies a direct connection.
   bool is_direct() const { return proxy_list_.Get().empty(); }
 
   // Returns the first valid proxy server.
   std::string proxy_server() const { return proxy_list_.Get(); }
 
   // See description in ProxyList::GetAnnotatedList().
   std::string GetAnnotatedProxyList();
 
   // Marks the current proxy as bad. Returns true if there is another proxy
@@ skipping 42 matching lines @@
   virtual ~ProxyResolver() {}
 
   // Query the proxy auto-config file (specified by |pac_url|) for the proxy to
   // use to load the given |query_url|.  Returns OK if successful or an error
   // code otherwise.
   virtual int GetProxyForURL(const GURL& query_url,
                              const GURL& pac_url,
                              ProxyInfo* results) = 0;
 };
 
+// Wrapper for invoking methods on a ProxyService synchronously.
+class SyncProxyServiceHelper
+    : public base::RefCountedThreadSafe<SyncProxyServiceHelper> {
+ public:
+  SyncProxyServiceHelper(MessageLoop* io_message_loop,
+                         ProxyService* proxy_service);
+
+  int ResolveProxy(const GURL& url, ProxyInfo* proxy_info);
+  int ReconsiderProxyAfterError(const GURL& url, ProxyInfo* proxy_info);
+
+ private:
+  void StartAsyncResolve(const GURL& url);
+  void StartAsyncReconsider(const GURL& url);
+
+  void OnCompletion(int result);
+
+  MessageLoop* io_message_loop_;
+  ProxyService* proxy_service_;
+
+  base::WaitableEvent event_;
+  CompletionCallbackImpl<SyncProxyServiceHelper> callback_;
+  ProxyInfo proxy_info_;
+  int result_;
+};
+
 }  // namespace net
 
 #endif  // NET_PROXY_PROXY_SERVICE_H_