sql::MetaTable.next_download_id, DownloadManager::GetNextId()

chrome/browser/renderer_host/download_throttling_resource_handler.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 "chrome/browser/renderer_host/download_throttling_resource_handler.h"
 
 #include "base/logging.h"
+#include "chrome/browser/download/download_id.h"
 #include "chrome/browser/download/download_util.h"
 #include "chrome/browser/renderer_host/download_resource_handler.h"
 #include "content/browser/renderer_host/resource_dispatcher_host.h"
+#include "content/browser/renderer_host/resource_dispatcher_host_request_info.h"
+#include "content/browser/resource_context.h"
 #include "content/common/resource_response.h"
 #include "net/base/io_buffer.h"
 #include "net/base/mime_sniffer.h"
 
 DownloadThrottlingResourceHandler::DownloadThrottlingResourceHandler(
     ResourceDispatcherHost* host,
     net::URLRequest* request,
     const GURL& url,
     int render_process_host_id,
     int render_view_id,
@@ skipping 145 matching lines @@
 
 void DownloadThrottlingResourceHandler::CancelDownload() {
   if (!request_closed_)
     host_->CancelRequest(render_process_host_id_, request_id_, false);
   Release();  // Release the additional reference from constructor.
 }
 
 void DownloadThrottlingResourceHandler::ContinueDownload() {
   DCHECK(!download_handler_.get());
   if (!request_closed_) {
+    ResourceDispatcherHostRequestInfo* info =
+        ResourceDispatcherHost::InfoForRequest(request_);
+    DownloadId dl_id;
+    void* next_download_id_thunk = info->context()->GetUserData(

[Randy Smith (Not in Mondays), 2011/08/03 21:10:29]

Will we also be able to clean this up when download_manager moves into content? 
If so, put in a TODO; if not, let's chat, as this is pretty gnarly casting code
and it would be good to find some other way to do this.

[benjhayden, 2011/08/04 17:15:00]

Done.

+        reinterpret_cast<void*>(BASE_HASH_NAMESPACE::hash<std::string>()(
+            "next_download_id_thunk")));
+    if (next_download_id_thunk != NULL) {
+      dl_id = reinterpret_cast<DownloadManager::GetNextIdThunkType*>(
+          next_download_id_thunk)->Run();
+    }
     download_handler_ =
         new DownloadResourceHandler(host_,
                                     render_process_host_id_,
                                     render_view_id_,
                                     request_id_,
                                     url_,
+                                    dl_id,
                                     host_->download_file_manager(),
                                     request_,
                                     false,
                                     DownloadSaveInfo());
     if (response_.get())
       download_handler_->OnResponseStarted(request_id_, response_.get());
 
     if (tmp_buffer_length_)
       CopyTmpBufferToDownloadHandler();
 
     // And let the request continue.
     host_->PauseRequest(render_process_host_id_, request_id_, false);
   }
   Release();  // Release the addtional reference from constructor.
 }
 
 void DownloadThrottlingResourceHandler::CopyTmpBufferToDownloadHandler() {
   // Copy over the tmp buffer.
   net::IOBuffer* buffer;
   int buf_size;
   if (download_handler_->OnWillRead(request_id_, &buffer, &buf_size,
                                     tmp_buffer_length_)) {
     CHECK(buf_size >= tmp_buffer_length_);
     memcpy(buffer->data(), tmp_buffer_->data(), tmp_buffer_length_);
     download_handler_->OnReadCompleted(request_id_, &tmp_buffer_length_);
   }
   tmp_buffer_length_ = 0;
   tmp_buffer_ = NULL;
 }