Implement redirect handling on MojoAsyncResourceHandler

content/browser/loader/mojo_async_resource_handler.cc

Index: content/browser/loader/mojo_async_resource_handler.cc
diff --git a/content/browser/loader/mojo_async_resource_handler.cc b/content/browser/loader/mojo_async_resource_handler.cc
index 6d5a9d7c4a08f396856ebee72852a861a6a3eb21..fbdb4bb78439b0c01f5362a95e4e205f279e2f65 100644
--- a/content/browser/loader/mojo_async_resource_handler.cc
+++ b/content/browser/loader/mojo_async_resource_handler.cc
@@ -127,8 +127,24 @@ bool MojoAsyncResourceHandler::OnRequestRedirected(
     const net::RedirectInfo& redirect_info,
     ResourceResponse* response,
     bool* defer) {
-  // Not implemented.
-  return false;
+  // Unlike OnResponseStarted, OnRequestRedirected will NOT be preceded by
+  // OnWillRead.
+  DCHECK(!shared_writer_);
+
+  *defer = true;
+  request()->LogBlockedBy("MojoAsyncResourceHandler");
+  did_defer_on_redirect_ = true;
+
+  NetLogObserver::PopulateResponseInfo(request(), response);
+  response->head.encoded_data_length = request()->GetTotalReceivedBytes();
+  response->head.request_start = request()->creation_time();
+  response->head.response_start = base::TimeTicks::Now();
+  // TODO(davidben): Is it necessary to pass the new first party URL for
+  // cookies? The only case where it can change is top-level navigation requests
+  // and hopefully those will eventually all be owned by the browser. It's
+  // possible this is still needed while renderer-owned ones exist.
+  url_loader_client_->OnReceiveRedirect(redirect_info, response->head);
+  return true;
 }
 
 bool MojoAsyncResourceHandler::OnResponseStarted(ResourceResponse* response,
@@ -218,8 +234,10 @@ bool MojoAsyncResourceHandler::OnReadCompleted(int bytes_read, bool* defer) {
     buffer_bytes_read_ = bytes_read;
     if (!CopyReadDataToDataPipe(defer))
       return false;
-    if (*defer)
-      OnDefer();
+    if (*defer) {
+      request()->LogBlockedBy("MojoAsyncResourceHandler");
+      did_defer_on_writing_ = true;
+    }
     return true;
   }
 
@@ -229,8 +247,10 @@ bool MojoAsyncResourceHandler::OnReadCompleted(int bytes_read, bool* defer) {
   // doesn't have |defer| parameter.
   if (!AllocateWriterIOBuffer(&buffer_, defer))
     return false;
-  if (*defer)
-    OnDefer();
+  if (*defer) {
+    request()->LogBlockedBy("MojoAsyncResourceHandler");
+    did_defer_on_writing_ = true;
+  }
   return true;
 }
 
@@ -245,11 +265,24 @@ void MojoAsyncResourceHandler::OnDataDownloaded(int bytes_downloaded) {
 }
 
 void MojoAsyncResourceHandler::FollowRedirect() {
-  NOTIMPLEMENTED();
+  if (!request()->status().is_success()) {
+    DVLOG(1) << "FollowRedirect for invalid request";
+    return;
+  }
+  if (!did_defer_on_redirect_) {
+    DVLOG(1) << "Malformed FollowRedirect request";
+    controller()->CancelWithError(net::ERR_ABORTED);
+    return;
+  }
+
+  DCHECK(!did_defer_on_writing_);

[dcheng, 2016/11/15 07:41:41]

So in general, loading is a large state machine. If the renderer gets out of
sync, I think we should probably be calling mojo::ReportBadMessage(...) to kill
it, right? Are there reasons where we'd want to continue?

(Also, I'm not sure if we're consistently doing this now; do you know what
happens for legacy IPC?)

[yhirano, 2016/11/15 08:08:24]

This dcheck is not affected by a malformed renderer. L272-L275 is the section
for the issue, and PS8 calls mojo::ReportBadMessage.

+  did_defer_on_redirect_ = false;
+  request()->LogUnblocked();
+  controller()->Resume();
 }
 
-void MojoAsyncResourceHandler::ResumeForTesting() {
-  Resume();
+void MojoAsyncResourceHandler::OnWritableForTesting() {
+  OnWritable(MOJO_RESULT_OK);
 }
 
 void MojoAsyncResourceHandler::SetAllocationSizeForTesting(size_t size) {
@@ -351,28 +384,41 @@ bool MojoAsyncResourceHandler::AllocateWriterIOBuffer(
   return true;
 }
 
-void MojoAsyncResourceHandler::Resume() {
-  if (!did_defer_)
+bool MojoAsyncResourceHandler::CheckForSufficientResource() {
+  if (has_checked_for_sufficient_resources_)
+    return true;
+  has_checked_for_sufficient_resources_ = true;
+
+  if (rdh_->HasSufficientResourcesForRequest(request()))
+    return true;
+
+  controller()->CancelWithError(net::ERR_INSUFFICIENT_RESOURCES);
+  return false;
+}
+
+void MojoAsyncResourceHandler::OnWritable(MojoResult result) {
+  if (!did_defer_on_writing_)
     return;
-  did_defer_ = false;
+  DCHECK(!did_defer_on_redirect_);
+  did_defer_on_writing_ = false;
 
   if (is_using_io_buffer_not_from_writer_) {
     // |buffer_| is set to a net::IOBufferWithSize. Write the buffer contents
     // to the data pipe.
     DCHECK_GT(buffer_bytes_read_, 0u);
-    if (!CopyReadDataToDataPipe(&did_defer_)) {
+    if (!CopyReadDataToDataPipe(&did_defer_on_writing_)) {
       controller()->CancelWithError(net::ERR_FAILED);
       return;
     }
   } else {
     // Allocate a buffer for the next OnWillRead call here.
-    if (!AllocateWriterIOBuffer(&buffer_, &did_defer_)) {
+    if (!AllocateWriterIOBuffer(&buffer_, &did_defer_on_writing_)) {
       controller()->CancelWithError(net::ERR_FAILED);
       return;
     }
   }
 
-  if (did_defer_) {
+  if (did_defer_on_writing_) {
     // Continue waiting.
     return;
   }
@@ -380,27 +426,6 @@ void MojoAsyncResourceHandler::Resume() {
   controller()->Resume();
 }
 
-void MojoAsyncResourceHandler::OnDefer() {
-  request()->LogBlockedBy("MojoAsyncResourceHandler");
-  did_defer_ = true;
-}
-
-bool MojoAsyncResourceHandler::CheckForSufficientResource() {
-  if (has_checked_for_sufficient_resources_)
-    return true;
-  has_checked_for_sufficient_resources_ = true;
-
-  if (rdh_->HasSufficientResourcesForRequest(request()))
-    return true;
-
-  controller()->CancelWithError(net::ERR_INSUFFICIENT_RESOURCES);
-  return false;
-}
-
-void MojoAsyncResourceHandler::OnWritable(MojoResult unused) {
-  Resume();
-}
-
 void MojoAsyncResourceHandler::Cancel() {
   const ResourceRequestInfoImpl* info = GetRequestInfo();
   ResourceDispatcherHostImpl::Get()->CancelRequestFromRenderer(