base::Bind: Convert HostResolver::Resolve.

net/base/host_resolver_impl.cc

 // Copyright (c) 2011 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.
 
 #include "net/base/host_resolver_impl.h"
 
 #if defined(OS_WIN)
 #include <Winsock2.h>
 #elif defined(OS_POSIX)
 #include <netdb.h>
 #endif
 
 #include <cmath>
 #include <deque>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/bind.h"
+#include "base/bind_helpers.h"
 #include "base/compiler_specific.h"
 #include "base/debug/debugger.h"
 #include "base/debug/stack_trace.h"
 #include "base/message_loop_proxy.h"
 #include "base/metrics/field_trial.h"
 #include "base/metrics/histogram.h"
 #include "base/stl_util.h"
 #include "base/string_util.h"
 #include "base/threading/worker_pool.h"
 #include "base/time.h"
@@ skipping 227 matching lines @@
 };
 
 //-----------------------------------------------------------------------------
 
 class HostResolverImpl::Request {
  public:
   Request(const BoundNetLog& source_net_log,
           const BoundNetLog& request_net_log,
           int id,
           const RequestInfo& info,
-          OldCompletionCallback* callback,
+          const CompletionCallback& callback,
           AddressList* addresses)
       : source_net_log_(source_net_log),
         request_net_log_(request_net_log),
         id_(id),
         info_(info),
         job_(NULL),
         callback_(callback),
         addresses_(addresses) {
   }
 
   // Mark the request as cancelled.
   void MarkAsCancelled() {
     job_ = NULL;
-    callback_ = NULL;
     addresses_ = NULL;
+    callback_.Reset();
   }
 
   bool was_cancelled() const {
-    return callback_ == NULL;
+    return callback_.is_null();
   }
 
   void set_job(Job* job) {
     DCHECK(job != NULL);
     // Identify which job the request is waiting on.
     job_ = job;
   }
 
   void OnComplete(int error, const AddressList& addrlist) {
     if (error == OK)
       *addresses_ = CreateAddressListUsingPort(addrlist, port());
-    OldCompletionCallback* callback = callback_;
+    CompletionCallback callback = callback_;
     MarkAsCancelled();
-    callback->Run(error);
+    callback.Run(error);
   }
 
   int port() const {
     return info_.port();
   }
 
   Job* job() const {
     return job_;
   }
 
@@ skipping 20 matching lines @@
   // Unique ID for this request. Used by observers to identify requests.
   int id_;
 
   // The request info that started the request.
   RequestInfo info_;
 
   // The resolve job (running in worker pool) that this request is dependent on.
   Job* job_;
 
   // The user's callback to invoke when the request completes.
-  OldCompletionCallback* callback_;
+  CompletionCallback callback_;
 
   // The address list to save result into.
   AddressList* addresses_;
 
   DISALLOW_COPY_AND_ASSIGN(Request);
 };
 
 //------------------------------------------------------------------------------
 
 // Provide a common macro to simplify code and readability. We must use a
@@ skipping 772 matching lines @@
   DCHECK(CalledOnValidThread());
   CHECK_GE(pool_index, 0);
   CHECK_LT(pool_index, POOL_COUNT);
   CHECK(jobs_.empty()) << "Can only set constraints during setup";
   JobPool* pool = job_pools_[pool_index];
   pool->SetConstraints(max_outstanding_jobs, max_pending_requests);
 }
 
 int HostResolverImpl::Resolve(const RequestInfo& info,
                               AddressList* addresses,
-                              OldCompletionCallback* callback,
+                              const CompletionCallback& callback,
                               RequestHandle* out_req,
                               const BoundNetLog& source_net_log) {
   DCHECK(addresses);
-  DCHECK(callback);
   DCHECK(CalledOnValidThread());
+  DCHECK_EQ(false, callback.is_null());

[willchan no longer on Chromium, 2011/11/14 16:45:12]

DCHECK(!callback.is_null())? What you have is fine too, just looks a bit weird.

 
   // Choose a unique ID number for observers to see.
   int request_id = next_request_id_++;
 
   // Make a log item for the request.
   BoundNetLog request_net_log = BoundNetLog::Make(net_log_,
       NetLog::SOURCE_HOST_RESOLVER_IMPL_REQUEST);
 
   // Update the net log and notify registered observers.
   OnStartRequest(source_net_log, request_net_log, request_id, info);
 
   // Build a key that identifies the request in the cache and in the
   // outstanding jobs map.
   Key key = GetEffectiveKeyForRequest(info);
 
   int rv = ResolveHelper(request_id, key, info, addresses, request_net_log);
   if (rv != ERR_DNS_CACHE_MISS) {
     OnFinishRequest(source_net_log, request_net_log, request_id, info,
                     rv,
                     0  /* os_error (unknown since from cache) */);
     return rv;
   }
 
-   // Create a handle for this request, and pass it back to the user if they
+  // Create a handle for this request, and pass it back to the user if they
   // asked for it (out_req != NULL).
   Request* req = new Request(source_net_log, request_net_log, request_id, info,
                              callback, addresses);
   if (out_req)
     *out_req = reinterpret_cast<RequestHandle>(req);
 
   // Next we need to attach our request to a "job". This job is responsible for
   // calling "getaddrinfo(hostname)" on a worker thread.
   scoped_refptr<Job> job;
 
@@ skipping 481 matching lines @@
   // resolv.conf changes so we don't need to do anything to clear that cache.
   if (cache_.get())
     cache_->clear();
   // Existing jobs will have been sent to the original server so they need to
   // be aborted. TODO(Craig): Should these jobs be restarted?
   AbortAllInProgressJobs();
   // |this| may be deleted inside AbortAllInProgressJobs().
 }
 
 }  // namespace net