PPAPI: Make blocking completion callbacks work.

ppapi/proxy/ppb_url_loader_proxy.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 "ppapi/proxy/ppb_url_loader_proxy.h"
 
 #include <algorithm>
 #include <deque>
 #include <vector>
 
@@ skipping 73 matching lines @@
 class URLLoader : public Resource, public PPB_URLLoader_API {
  public:
   URLLoader(const HostResource& resource);
   virtual ~URLLoader();
 
   // Resource overrides.
   virtual PPB_URLLoader_API* AsPPB_URLLoader_API() OVERRIDE;
 
   // PPB_URLLoader_API implementation.
   virtual int32_t Open(PP_Resource request_id,
-                       PP_CompletionCallback callback) OVERRIDE;
-  virtual int32_t FollowRedirect(PP_CompletionCallback callback) OVERRIDE;
+                       scoped_refptr<TrackedCallback> callback) OVERRIDE;
+  virtual int32_t FollowRedirect(
+      scoped_refptr<TrackedCallback> callback) OVERRIDE;
   virtual PP_Bool GetUploadProgress(int64_t* bytes_sent,
                                     int64_t* total_bytes_to_be_sent) OVERRIDE;
   virtual PP_Bool GetDownloadProgress(
       int64_t* bytes_received,
       int64_t* total_bytes_to_be_received) OVERRIDE;
   virtual PP_Resource GetResponseInfo() OVERRIDE;
-  virtual int32_t ReadResponseBody(void* buffer,
-                                   int32_t bytes_to_read,
-                                   PP_CompletionCallback callback) OVERRIDE;
+  virtual int32_t ReadResponseBody(
+      void* buffer,
+      int32_t bytes_to_read,
+      scoped_refptr<TrackedCallback> callback) OVERRIDE;
   virtual int32_t FinishStreamingToFile(
-      PP_CompletionCallback callback) OVERRIDE;
+      scoped_refptr<TrackedCallback> callback) OVERRIDE;
   virtual void Close() OVERRIDE;
   virtual void GrantUniversalAccess() OVERRIDE;
   virtual void SetStatusCallback(
       PP_URLLoaderTrusted_StatusCallback cb) OVERRIDE;
 
   // Called when the browser has new up/download progress to report.
   void UpdateProgress(const PPBURLLoader_UpdateProgress_Params& params);
 
   // Called when the browser responds to our ReadResponseBody request.
   void ReadResponseBodyAck(int32_t result, const std::string& data);
@@ skipping 54 matching lines @@
 URLLoader::~URLLoader() {
   if (response_info_)
     PpapiGlobals::Get()->GetResourceTracker()->ReleaseResource(response_info_);
 }
 
 PPB_URLLoader_API* URLLoader::AsPPB_URLLoader_API() {
   return this;
 }
 
 int32_t URLLoader::Open(PP_Resource request_id,
-                        PP_CompletionCallback callback) {
+                        scoped_refptr<TrackedCallback> callback) {
   EnterResourceNoLock<thunk::PPB_URLRequestInfo_API> enter(request_id, true);
   if (enter.failed()) {
     Log(PP_LOGLEVEL_ERROR, "PPB_URLLoader.Open: The URL you're requesting is "
         " on a different security origin than your plugin. To request "
         " cross-origin resources, see "
         " PP_URLREQUESTPROPERTY_ALLOWCROSSORIGINREQUESTS.");
     return PP_ERROR_BADRESOURCE;
   }
 
   if (TrackedCallback::IsPending(current_callback_))
     return PP_ERROR_INPROGRESS;
 
-  if (!callback.func)
-    return PP_ERROR_BLOCKS_MAIN_THREAD;
-  current_callback_ = new TrackedCallback(this, callback);
+  current_callback_ = callback;
 
   GetDispatcher()->Send(new PpapiHostMsg_PPBURLLoader_Open(
       API_ID_PPB_URL_LOADER, host_resource(), enter.object()->GetData()));
   return PP_OK_COMPLETIONPENDING;
 }
 
-int32_t URLLoader::FollowRedirect(PP_CompletionCallback callback) {
+int32_t URLLoader::FollowRedirect(scoped_refptr<TrackedCallback> callback) {
   if (TrackedCallback::IsPending(current_callback_))
     return PP_ERROR_INPROGRESS;
 
-  if (!callback.func)
-    return PP_ERROR_BLOCKS_MAIN_THREAD;
-  current_callback_ = new TrackedCallback(this, callback);
+  current_callback_ = callback;
 
   GetDispatcher()->Send(new PpapiHostMsg_PPBURLLoader_FollowRedirect(
       API_ID_PPB_URL_LOADER, host_resource()));
   return PP_OK_COMPLETIONPENDING;
 }
 
 PP_Bool URLLoader::GetUploadProgress(int64_t* bytes_sent,
                                      int64_t* total_bytes_to_be_sent) {
   if (bytes_sent_ == -1) {
     *bytes_sent = 0;
@@ skipping 30 matching lines @@
         response_id);
   }
 
   // The caller expects to get a ref, and we want to keep holding ours.
   PpapiGlobals::Get()->GetResourceTracker()->AddRefResource(response_info_);
   return response_info_;
 }
 
 int32_t URLLoader::ReadResponseBody(void* buffer,
                                     int32_t bytes_to_read,
-                                    PP_CompletionCallback callback) {
+                                    scoped_refptr<TrackedCallback> callback) {
   if (!buffer || bytes_to_read <= 0)
     return PP_ERROR_BADARGUMENT;  // Must specify an output buffer.
   if (TrackedCallback::IsPending(current_callback_))
     return PP_ERROR_INPROGRESS;  // Can only have one request pending.
 
-  // Currently we don't support sync calls to read. We'll need to revisit
-  // how this works when we allow blocking calls (from background threads).
-  if (!callback.func)
-    return PP_ERROR_BADARGUMENT;
-
   if (static_cast<size_t>(bytes_to_read) <= buffer_.size()) {
     // Special case: we've buffered enough data to be able to synchronously
     // return data to the caller. Do so without making IPCs.
     PopBuffer(buffer, bytes_to_read);
     return bytes_to_read;
   }
 
-  current_callback_ = new TrackedCallback(this, callback);
+  current_callback_ = callback;
   current_read_buffer_ = buffer;
   current_read_buffer_size_ = bytes_to_read;
 
   GetDispatcher()->Send(new PpapiHostMsg_PPBURLLoader_ReadResponseBody(
       API_ID_PPB_URL_LOADER, host_resource(), bytes_to_read));
   return PP_OK_COMPLETIONPENDING;
 }
 
-int32_t URLLoader::FinishStreamingToFile(PP_CompletionCallback callback) {
+int32_t URLLoader::FinishStreamingToFile(
+    scoped_refptr<TrackedCallback> callback) {
   if (TrackedCallback::IsPending(current_callback_))
     return PP_ERROR_INPROGRESS;
 
-  if (!callback.func)
-    return PP_ERROR_BLOCKS_MAIN_THREAD;
-  current_callback_ = new TrackedCallback(this, callback);
+  current_callback_ = callback;
 
   GetDispatcher()->Send(new PpapiHostMsg_PPBURLLoader_FinishStreamingToFile(
       API_ID_PPB_URL_LOADER, host_resource()));
   return PP_OK_COMPLETIONPENDING;
 }
 
 void URLLoader::Close() {
   GetDispatcher()->Send(new PpapiHostMsg_PPBURLLoader_Close(
       API_ID_PPB_URL_LOADER, host_resource()));
 }
@@ skipping 293 matching lines @@
 }
 
 void PPB_URLLoader_Proxy::OnCallback(int32_t result,
                                      const HostResource& resource) {
   dispatcher()->Send(new PpapiMsg_PPBURLLoader_CallbackComplete(
       API_ID_PPB_URL_LOADER, resource, result));
 }
 
 }  // namespace proxy
 }  // namespace ppapi