Download resumption - Preliminary

content/browser/download/download_manager_impl.cc

Index: content/browser/download/download_manager_impl.cc
diff --git a/content/browser/download/download_manager_impl.cc b/content/browser/download/download_manager_impl.cc
index 6099eca4cf8befcdd88d2f9e95ca982b51be9192..8f668bc54cf4b24a98e1d4c3220c3e8cdb89dc72 100644
--- a/content/browser/download/download_manager_impl.cc
+++ b/content/browser/download/download_manager_impl.cc
@@ -39,6 +39,7 @@
 #include "content/public/browser/render_process_host.h"
 #include "content/public/browser/resource_context.h"
 #include "content/public/browser/web_contents_delegate.h"
+#include "content/public/common/referrer.h"
 #include "net/base/load_flags.h"
 #include "net/base/upload_data.h"
 #include "net/url_request/url_request_context.h"
@@ -47,7 +48,8 @@
 namespace content {
 namespace {
 
-void BeginDownload(scoped_ptr<DownloadUrlParameters> params) {
+void BeginDownload(scoped_ptr<DownloadUrlParameters> params,
+                   DownloadId download_id) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
   // ResourceDispatcherHost{Base} is-not-a URLRequest::Delegate, and
   // DownloadUrlParameters can-not include resource_dispatcher_host_impl.h, so
@@ -101,6 +103,9 @@ void BeginDownload(scoped_ptr<DownloadUrlParameters> params) {
       params->render_view_host_routing_id(),
       params->prefer_cache(),
       save_info.Pass(),
+      params->last_modified(),
+      params->etag(),
+      download_id,
       params->callback());
 }
 
@@ -171,10 +176,8 @@ class DownloadItemFactoryImpl : public DownloadItemFactory {
     virtual DownloadItemImpl* CreateActiveItem(
         DownloadItemImplDelegate* delegate,
         const DownloadCreateInfo& info,
-        scoped_ptr<DownloadRequestHandleInterface> request_handle,
         const net::BoundNetLog& bound_net_log) OVERRIDE {
-      return new DownloadItemImpl(delegate, info, request_handle.Pass(),
-                                  bound_net_log);
+      return new DownloadItemImpl(delegate, info, bound_net_log);
     }
 
     virtual DownloadItemImpl* CreateSavePageItem(
@@ -344,9 +347,6 @@ DownloadItem* DownloadManagerImpl::StartDownload(
     scoped_ptr<ByteStreamReader> stream) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
-  net::BoundNetLog bound_net_log =
-      net::BoundNetLog::Make(net_log_, net::NetLog::SOURCE_DOWNLOAD);
-
   FilePath default_download_directory;
   if (delegate_) {
     FilePath website_save_directory;      // Unused
@@ -358,8 +358,8 @@ DownloadItem* DownloadManagerImpl::StartDownload(
   // We create the DownloadItem before the DownloadFile because the
   // DownloadItem already needs to handle a state in which there is
   // no associated DownloadFile (history downloads, !IN_PROGRESS downloads)
-  DownloadItemImpl* download =
-      CreateDownloadItem(info.get(), bound_net_log);
+  DownloadItemImpl* download = CreateDownloadItem(info.get());
+  net::BoundNetLog bound_net_log = download->GetBoundNetLog();
   scoped_ptr<DownloadFile> download_file(
       file_factory_->CreateFile(
           info->save_info.Pass(), default_download_directory,
@@ -367,7 +367,9 @@ DownloadItem* DownloadManagerImpl::StartDownload(
           delegate_->GenerateFileHash(),
           stream.Pass(), bound_net_log,
           download->DestinationObserverAsWeakPtr()));
-  download->Start(download_file.Pass());
+  scoped_ptr<DownloadRequestHandleInterface> req_handle(
+      new DownloadRequestHandle(info->request_handle));
+  download->Start(download_file.Pass(), req_handle.Pass());
 
   // Delay notification until after Start() so that download_file is bound
   // to download and all the usual setters (e.g. Cancel) work.
@@ -420,19 +422,40 @@ BrowserContext* DownloadManagerImpl::GetBrowserContext() const {
 }
 
 DownloadItemImpl* DownloadManagerImpl::CreateDownloadItem(
-    DownloadCreateInfo* info, const net::BoundNetLog& bound_net_log) {
+    DownloadCreateInfo* info) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
   if (!info->download_id.IsValid())
     info->download_id = GetNextId();
-  DownloadItemImpl* download = item_factory_->CreateActiveItem(
-      this, *info,
-      scoped_ptr<DownloadRequestHandleInterface>(
-          new DownloadRequestHandle(info->request_handle)).Pass(),
-      bound_net_log);
 
-  DCHECK(!ContainsKey(downloads_, download->GetId()));
-  downloads_[download->GetId()] = download;
+  int32 download_id = info->download_id.local();
+  DownloadItemImpl* download = NULL;
+  bool resuming = ContainsKey(downloads_, download_id);
+  if (resuming) {
+    download = downloads_[download_id];
+    DCHECK(download != NULL);
+    DCHECK(download->IsInProgress());
+  }
+
+  if (download) {
+    // Reuse an interrupted |DownloadItem|.
+    DCHECK(download->IsInterrupted());
+  } else {
+    // Create a new |DownloadItem|.
+    // |bound_net_log| will be used for logging the both the download item's and
+    // the download file's events.
+    net::BoundNetLog bound_net_log =
+        net::BoundNetLog::Make(net_log_, net::NetLog::SOURCE_DOWNLOAD);
+    download = item_factory_->CreateActiveItem(this, *info, bound_net_log);
+
+    DCHECK(!ContainsKey(downloads_, download->GetId()));
+    downloads_[download->GetId()] = download;
+  }
+
+  DVLOG(20) << __FUNCTION__ << "()"
+            << " info " << info->DebugString()
+            << " download " << download->DebugString(true);
+
   DCHECK(!ContainsKey(active_downloads_, download->GetId()));
   active_downloads_[download->GetId()] = download;
 
@@ -486,8 +509,17 @@ void DownloadManagerImpl::DownloadCompleted(DownloadItemImpl* download) {
 void DownloadManagerImpl::CancelDownload(int32 download_id) {
   // A cancel at the right time could remove the download from the
   // |active_downloads_| map before we get here.
-  if (ContainsKey(active_downloads_, download_id))
-    active_downloads_[download_id]->Cancel(true);
+  if (!ContainsKey(active_downloads_, download_id))
+    return;
+
+  DownloadItem* download = active_downloads_[download_id];
+
+  VLOG(20) << __FUNCTION__ << "() download = " << download->DebugString(true);
+
+  if (!download->IsInProgress())
+    return;
+
+  download->Cancel(true);
 }
 
 void DownloadManagerImpl::DownloadStopped(DownloadItemImpl* download) {
@@ -502,6 +534,18 @@ void DownloadManagerImpl::DownloadStopped(DownloadItemImpl* download) {
   AssertStateConsistent(download);
 }
 
+// Resume a download of a specific URL. We send the request to the
+// ResourceDispatcherHost, and let it send us responses like a regular
+// download.
+void DownloadManagerImpl::ResumeInterruptedDownload(
+    scoped_ptr<content::DownloadUrlParameters> params,
+    content::DownloadId id) {
+  BrowserThread::PostTask(
+      BrowserThread::IO,
+      FROM_HERE,
+      base::Bind(&BeginDownload, base::Passed(params.Pass()), id));
+}
+
 void DownloadManagerImpl::RemoveFromActiveList(DownloadItemImpl* download) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK(download);
@@ -587,8 +631,12 @@ void DownloadManagerImpl::DownloadUrl(
     DCHECK(params->prefer_cache());
     DCHECK(params->method() == "POST");
   }
-  BrowserThread::PostTask(BrowserThread::IO, FROM_HERE, base::Bind(
-      &BeginDownload, base::Passed(params.Pass())));
+  BrowserThread::PostTask(
+      BrowserThread::IO, FROM_HERE,
+      base::Bind(
+          &BeginDownload,
+          base::Passed(params.Pass()),
+          DownloadId()));
 }
 
 void DownloadManagerImpl::AddObserver(Observer* observer) {