URLRequestJob: change ReadRawData contract

content/browser/webui/url_data_manager_backend.cc

 // Copyright (c) 2012 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 "content/browser/webui/url_data_manager_backend.h"
 
 #include <set>
 
 #include "base/basictypes.h"
 #include "base/bind.h"
@@ skipping 101 matching lines @@
  public:
   // |is_incognito| set when job is generated from an incognito profile.
   URLRequestChromeJob(net::URLRequest* request,
                       net::NetworkDelegate* network_delegate,
                       URLDataManagerBackend* backend,
                       bool is_incognito);
 
   // net::URLRequestJob implementation.
   void Start() override;
   void Kill() override;
-  bool ReadRawData(net::IOBuffer* buf, int buf_size, int* bytes_read) override;
+  int ReadRawData(net::IOBuffer* buf, int buf_size) override;
   bool GetMimeType(std::string* mime_type) const override;
   int GetResponseCode() const override;
   void GetResponseInfo(net::HttpResponseInfo* info) override;
 
   // Used to notify that the requested data's |mime_type| is ready.
   void MimeTypeAvailable(const std::string& mime_type);
 
   // Called by ChromeURLDataManager to notify us that the data blob is ready
   // for us.
   void DataAvailable(base::RefCountedMemory* bytes);
@@ skipping 51 matching lines @@
   static void CheckStoragePartitionMatches(
       int render_process_id,
       const GURL& url,
       const base::WeakPtr<URLRequestChromeJob>& job);
 
   // Specific resources require unsafe-eval in the Content Security Policy.
   bool RequiresUnsafeEval() const;
 
   // Do the actual copy from data_ (the data we're serving) into |buf|.
   // Separate from ReadRawData so we can handle async I/O.
-  void CompleteRead(net::IOBuffer* buf, int buf_size, int* bytes_read);
+  // return value is either >= 0 to indicate a successful read and count of
+  // bytes read, or < 0 to indicate an error.

[davidben, 2015/11/03 22:50:05]

It doesn't look like this function can actually return an error.

[xunjieli, 2015/11/04 01:26:51]

Done.

+  int CompleteRead(net::IOBuffer* buf, int buf_size);
 
   // The actual data we're serving.  NULL until it's been fetched.
   scoped_refptr<base::RefCountedMemory> data_;
   // The current offset into the data that we're handing off to our
   // callers via the Read interfaces.
   int data_offset_;
 
   // For async reads, we keep around a pointer to the buffer that
   // we're reading into.
   scoped_refptr<net::IOBuffer> pending_buf_;
@@ skipping 124 matching lines @@
 }
 
 void URLRequestChromeJob::MimeTypeAvailable(const std::string& mime_type) {
   set_mime_type(mime_type);
   NotifyHeadersComplete();
 }
 
 void URLRequestChromeJob::DataAvailable(base::RefCountedMemory* bytes) {
   TRACE_EVENT_ASYNC_END0("browser", "DataManager:Request", this);
   if (bytes) {
-    // The request completed, and we have all the data.
-    // Clear any IO pending status.
-    SetStatus(net::URLRequestStatus());
-
     data_ = bytes;
-    int bytes_read;
     if (pending_buf_.get()) {
       CHECK(pending_buf_->data());
-      CompleteRead(pending_buf_.get(), pending_buf_size_, &bytes_read);
+      int result = CompleteRead(pending_buf_.get(), pending_buf_size_);
       pending_buf_ = NULL;
-      NotifyReadComplete(bytes_read);
+      ReadRawDataComplete(result);
     }
   } else {
     // The request failed.
-    NotifyDone(net::URLRequestStatus(net::URLRequestStatus::FAILED,
-                                     net::ERR_FAILED));
+    ReadRawDataComplete(net::ERR_FAILED);
   }
 }
 
 base::WeakPtr<URLRequestChromeJob> URLRequestChromeJob::AsWeakPtr() {
   return weak_factory_.GetWeakPtr();
 }
 
-bool URLRequestChromeJob::ReadRawData(net::IOBuffer* buf, int buf_size,
-                                      int* bytes_read) {
+int URLRequestChromeJob::ReadRawData(net::IOBuffer* buf, int buf_size) {
   if (!data_.get()) {
-    SetStatus(net::URLRequestStatus(net::URLRequestStatus::IO_PENDING, 0));
     DCHECK(!pending_buf_.get());
     CHECK(buf->data());
     pending_buf_ = buf;
     pending_buf_size_ = buf_size;
-    return false;  // Tell the caller we're still waiting for data.
+    return net::ERR_IO_PENDING;
   }
 
   // Otherwise, the data is available.
-  CompleteRead(buf, buf_size, bytes_read);
-  return true;
+  return CompleteRead(buf, buf_size);
 }
 
-void URLRequestChromeJob::CompleteRead(net::IOBuffer* buf, int buf_size,
-                                       int* bytes_read) {
-  int remaining = static_cast<int>(data_->size()) - data_offset_;
+int URLRequestChromeJob::CompleteRead(net::IOBuffer* buf, int buf_size) {
+  int remaining = data_->size() - data_offset_;
   if (buf_size > remaining)
     buf_size = remaining;
   if (buf_size > 0) {
     // TODO(pkasting): Remove ScopedTracker below once crbug.com/455423 is
     // fixed.
     tracked_objects::ScopedTracker tracking_profile(
         FROM_HERE_WITH_EXPLICIT_FUNCTION(
             "455423 URLRequestChromeJob::CompleteRead memcpy"));
     memcpy(buf->data(), data_->front() + data_offset_, buf_size);
     data_offset_ += buf_size;
   }
-  *bytes_read = buf_size;
+  return buf_size;
 }
 
 void URLRequestChromeJob::CheckStoragePartitionMatches(
     int render_process_id,
     const GURL& url,
     const base::WeakPtr<URLRequestChromeJob>& job) {
   // The embedder could put some webui pages in separate storage partition.
   // RenderProcessHostImpl::IsSuitableHost would guard against top level pages
   // being in the same process. We do an extra check to guard against an
   // exploited renderer pretending to add them as a subframe. We skip this check
@@ skipping 370 matching lines @@
 
 }  // namespace
 
 net::URLRequestJobFactory::ProtocolHandler*
 CreateDevToolsProtocolHandler(content::ResourceContext* resource_context,
                               bool is_incognito) {
   return new DevToolsJobFactory(resource_context, is_incognito);
 }
 
 }  // namespace content