Revert "URLRequestJob: change ReadRawData contract"

content/browser/net/view_http_cache_job_factory.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/net/view_http_cache_job_factory.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/callback.h"
 #include "base/compiler_specific.h"
 #include "base/location.h"
 #include "base/memory/weak_ptr.h"
-#include "base/numerics/safe_conversions.h"
 #include "base/single_thread_task_runner.h"
 #include "base/strings/string_util.h"
 #include "base/thread_task_runner_handle.h"
 #include "content/public/common/url_constants.h"
 #include "net/base/completion_callback.h"
 #include "net/base/net_errors.h"
 #include "net/url_request/url_request.h"
 #include "net/url_request/url_request_simple_job.h"
 #include "net/url_request/view_cache_helper.h"
 
@@ skipping 14 matching lines @@
 
   // net::URLRequestJob implementation.
   void Start() override;
   void Kill() override;
   bool GetMimeType(std::string* mime_type) const override {
     return core_->GetMimeType(mime_type);
   }
   bool GetCharset(std::string* charset) override {
     return core_->GetCharset(charset);
   }
-  int ReadRawData(net::IOBuffer* buf, int buf_size) override {
-    return core_->ReadRawData(buf, buf_size);
+  bool ReadRawData(net::IOBuffer* buf, int buf_size, int* bytes_read) override {
+    return core_->ReadRawData(buf, buf_size, bytes_read);
   }
 
  private:
   class Core : public base::RefCounted<Core> {
    public:
     Core()
         : data_offset_(0),
           callback_(base::Bind(&Core::OnIOComplete, this)) {
     }
 
     int Start(const net::URLRequest& request, const base::Closure& callback);
 
     // Prevents it from invoking its callback. It will self-delete.
     void Orphan() {
       user_callback_.Reset();
     }
 
     bool GetMimeType(std::string* mime_type) const;
     bool GetCharset(std::string* charset);
-    int ReadRawData(net::IOBuffer* buf, int buf_size);
+    bool ReadRawData(net::IOBuffer* buf, int buf_size, int* bytes_read);
 
    private:
     friend class base::RefCounted<Core>;
 
     ~Core() {}
 
     // Called when ViewCacheHelper completes the operation.
     void OnIOComplete(int result);
 
     std::string data_;
@@ skipping 78 matching lines @@
 bool ViewHttpCacheJob::Core::GetMimeType(std::string* mime_type) const {
   mime_type->assign("text/html");
   return true;
 }
 
 bool ViewHttpCacheJob::Core::GetCharset(std::string* charset) {
   charset->assign("UTF-8");
   return true;
 }
 
-int ViewHttpCacheJob::Core::ReadRawData(net::IOBuffer* buf, int buf_size) {
-  int remaining = base::checked_cast<int>(data_.size()) - data_offset_;
+bool ViewHttpCacheJob::Core::ReadRawData(net::IOBuffer* buf,
+                                         int buf_size,
+                                         int* bytes_read) {
+  DCHECK(bytes_read);
+  int remaining = static_cast<int>(data_.size()) - data_offset_;
   if (buf_size > remaining)
     buf_size = remaining;
   memcpy(buf->data(), data_.data() + data_offset_, buf_size);
   data_offset_ += buf_size;
-  return buf_size;
+  *bytes_read = buf_size;
+  return true;
 }
 
 void ViewHttpCacheJob::Core::OnIOComplete(int result) {
   DCHECK_EQ(net::OK, result);
 
   if (!user_callback_.is_null())
     user_callback_.Run();
 
   // We may be holding the last reference to this job. Do not access |this|
   // after Release().
   Release();  // Acquired on Start().
 }
 
 }  // namespace.
 
 // Static.
 bool ViewHttpCacheJobFactory::IsSupportedURL(const GURL& url) {
   return url.SchemeIs(kChromeUIScheme) &&
          url.host() == kChromeUINetworkViewCacheHost;
 }
 
 // Static.
 net::URLRequestJob* ViewHttpCacheJobFactory::CreateJobForRequest(
     net::URLRequest* request, net::NetworkDelegate* network_delegate) {
   return new ViewHttpCacheJob(request, network_delegate);
 }
 
 }  // namespace content