Refactor PPAPI proxy resource handling to maintain which host they came from,...

ppapi/proxy/ppb_url_loader_proxy.cc

 // Copyright (c) 2010 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 <vector>
 
 #include "base/logging.h"
 #include "build/build_config.h"
 #include "ppapi/c/pp_completion_callback.h"
 #include "ppapi/c/pp_errors.h"
 #include "ppapi/c/pp_resource.h"
 #include "ppapi/c/ppb_url_loader.h"
 #include "ppapi/c/trusted/ppb_url_loader_trusted.h"
 #include "ppapi/proxy/host_dispatcher.h"
 #include "ppapi/proxy/plugin_dispatcher.h"
 #include "ppapi/proxy/plugin_resource.h"
+#include "ppapi/proxy/plugin_resource_tracker.h"
 #include "ppapi/proxy/ppapi_messages.h"
 #include "ppapi/proxy/ppb_url_response_info_proxy.h"
 
 #if defined(OS_LINUX)
 #include <sys/shm.h>
 #endif
 
 namespace pp {
 namespace proxy {
 
 class URLLoader : public PluginResource {
  public:
-  URLLoader(PP_Instance instance);
+  URLLoader(PP_Instance instance, SerializedResource resource);
   virtual ~URLLoader();
 
   // Resource overrides.
   virtual URLLoader* AsURLLoader() { return this; }
 
+  PP_Resource GetResponseInfo();
+
   // Initialized to -1. Will be set to nonnegative values by the UpdateProgress
   // message when the values are known.
   int64_t bytes_sent_;
   int64_t total_bytes_to_be_sent_;
   int64_t bytes_received_;
   int64_t total_bytes_to_be_received_;
 
   // When an asynchronous read is pending, this will contain the callback and
   // the buffer to put the data.
   PP_CompletionCallback current_read_callback_;
   char* current_read_buffer_;
 
+  // Cached copy of the response info. When nonzero, we're holding a reference
+  // to this resource.
+  PP_Resource response_info_;
+
  private:
   DISALLOW_COPY_AND_ASSIGN(URLLoader);
 };
 
-URLLoader::URLLoader(PP_Instance instance)
-    : PluginResource(instance),
+URLLoader::URLLoader(PP_Instance instance, SerializedResource resource)
+    : PluginResource(instance, resource),
       bytes_sent_(-1),
       total_bytes_to_be_sent_(-1),
       bytes_received_(-1),
       total_bytes_to_be_received_(-1),
       current_read_callback_(PP_MakeCompletionCallback(NULL, NULL)),
-      current_read_buffer_(NULL) {
+      current_read_buffer_(NULL),
+      response_info_(0) {
 }
 
 URLLoader::~URLLoader() {
+  if (response_info_)
+    PluginResourceTracker::GetInstance()->ReleaseResource(response_info_);
+}
+
+PP_Resource URLLoader::GetResponseInfo() {
+  if (!response_info_) {
+    PluginDispatcher* dispatcher = PluginDispatcher::GetForInstance(instance());
+    if (!dispatcher)
+      return 0;
+
+    SerializedResource response_id;
+    dispatcher->Send(new PpapiHostMsg_PPBURLLoader_GetResponseInfo(
+        INTERFACE_ID_PPB_URL_LOADER, host_resource(), &response_id));
+    if (response_id.is_null())
+      return 0;
+
+    response_info_ = PPB_URLResponseInfo_Proxy::CreateResponseForResource(
+        instance(), response_id);
+  }
+
+  // The caller expects to get a ref, and we want to keep holding ours.
+  PluginResourceTracker::GetInstance()->AddRefResource(response_info_);
+  return response_info_;
 }
 
 namespace {
 
-// Converts the given loader ID to the dispatcher associated with it, or NULL
-// if it couldn't be found.
-PluginDispatcher* DispatcherFromURLLoader(PP_Resource loader_id) {
-  URLLoader* object = PluginResource::GetAs<URLLoader>(loader_id);
-  if (!object)
-    return NULL;
-  return PluginDispatcher::GetForInstance(object->instance());
+// Converts the given loader ID to the dispatcher associated with it and the
+// loader object. Returns true if the object was found.
+bool RoutingDataFromURLLoader(PP_Resource loader_id,
+                              URLLoader** loader_object,
+                              PluginDispatcher** dispatcher) {
+  *loader_object = PluginResource::GetAs<URLLoader>(loader_id);
+  if (!*loader_object)
+    return false;
+  *dispatcher = PluginDispatcher::GetForInstance((*loader_object)->instance());
+  return !!*dispatcher;
 }
 
 // Plugin PPB_URLLoader implmentation ------------------------------------------
 
 PP_Resource Create(PP_Instance instance_id) {
   PluginDispatcher* dispatcher = PluginDispatcher::GetForInstance(instance_id);
   if (!dispatcher)
     return 0;
 
-  PP_Resource result = 0;
+  SerializedResource result;
   dispatcher->Send(new PpapiHostMsg_PPBURLLoader_Create(
       INTERFACE_ID_PPB_URL_LOADER, instance_id, &result));
-  if (result)
-    PPB_URLLoader_Proxy::TrackPluginResource(instance_id, result);
-  return result;
+  if (result.is_null())
+    return 0;
+  return PPB_URLLoader_Proxy::TrackPluginResource(instance_id, result);
 }
 
 PP_Bool IsURLLoader(PP_Resource resource) {
   URLLoader* object = PluginResource::GetAs<URLLoader>(resource);
   return BoolToPPBool(!!object);
 }
 
 int32_t Open(PP_Resource loader_id,
              PP_Resource request_id,
              PP_CompletionCallback callback) {
-  PluginDispatcher* dispatcher = DispatcherFromURLLoader(loader_id);
-  if (!dispatcher)
+  URLLoader* loader_object;
+  PluginDispatcher* dispatcher;
+  if (!RoutingDataFromURLLoader(loader_id, &loader_object, &dispatcher))
+    return PP_ERROR_BADRESOURCE;
+  PluginResource* request_object =
+      PluginResourceTracker::GetInstance()->GetResourceObject(request_id);
+  if (!request_object)
     return PP_ERROR_BADRESOURCE;
 
   dispatcher->Send(new PpapiHostMsg_PPBURLLoader_Open(
-      INTERFACE_ID_PPB_URL_LOADER, loader_id, request_id,
+      INTERFACE_ID_PPB_URL_LOADER, loader_object->host_resource(),
+      request_object->host_resource(),
       dispatcher->callback_tracker().SendCallback(callback)));
   return PP_ERROR_WOULDBLOCK;
 }
 
 int32_t FollowRedirect(PP_Resource loader_id,
                        PP_CompletionCallback callback) {
-  PluginDispatcher* dispatcher = DispatcherFromURLLoader(loader_id);
-  if (!dispatcher)
+  URLLoader* loader_object;
+  PluginDispatcher* dispatcher;
+  if (!RoutingDataFromURLLoader(loader_id, &loader_object, &dispatcher))
     return PP_ERROR_BADRESOURCE;
 
   dispatcher->Send(new PpapiHostMsg_PPBURLLoader_FollowRedirect(
-      INTERFACE_ID_PPB_URL_LOADER, loader_id,
+      INTERFACE_ID_PPB_URL_LOADER, loader_object->host_resource(),
       dispatcher->callback_tracker().SendCallback(callback)));
   return PP_ERROR_WOULDBLOCK;
 }
 
 PP_Bool GetUploadProgress(PP_Resource loader_id,
                           int64_t* bytes_sent,
                           int64_t* total_bytes_to_be_sent) {
   URLLoader* object = PluginResource::GetAs<URLLoader>(loader_id);
   if (!object || object->bytes_sent_ == -1) {
     *bytes_sent = 0;
@@ skipping 16 matching lines @@
   }
   *bytes_received = object->bytes_received_;
   *total_bytes_to_be_received = object->total_bytes_to_be_received_;
   return PP_TRUE;
 }
 
 PP_Resource GetResponseInfo(PP_Resource loader_id) {
   URLLoader* object = PluginResource::GetAs<URLLoader>(loader_id);
   if (!object)
     return 0;
-
-  // If we find that plugins are frequently requesting the response info, we
-  // can improve performance by caching the PP_Resource in the URLLoader
-  // object. This way we only have to do IPC for the first request. However,
-  // it seems that most plugins will only call this once so there's no use
-  // optimizing this case.
-
-  PP_Resource result;
-  PluginDispatcher* dispatcher = PluginDispatcher::GetForInstance(
-      object->instance());
-  if (!dispatcher)
-    return PP_ERROR_BADRESOURCE;
-
-  dispatcher->Send(new PpapiHostMsg_PPBURLLoader_GetResponseInfo(
-      INTERFACE_ID_PPB_URL_LOADER, loader_id, &result));
-  if (PluginResourceTracker::GetInstance()->
-          PreparePreviouslyTrackedResource(result))
-    return result;
-
-  // Tell the response info to create a tracking object and add it to the
-  // resource tracker.
-  PPB_URLResponseInfo_Proxy::TrackPluginResource(object->instance(), result);
-  return result;
+  return object->GetResponseInfo();
 }
 
 int32_t ReadResponseBody(PP_Resource loader_id,
                          char* buffer,
                          int32_t bytes_to_read,
                          PP_CompletionCallback callback) {
-  URLLoader* object = PluginResource::GetAs<URLLoader>(loader_id);
-  if (!object)
-    return PP_ERROR_BADRESOURCE;
-  PluginDispatcher* dispatcher = PluginDispatcher::GetForInstance(
-      object->instance());
-  if (!dispatcher)
+  URLLoader* loader_object;
+  PluginDispatcher* dispatcher;
+  if (!RoutingDataFromURLLoader(loader_id, &loader_object, &dispatcher))
     return PP_ERROR_BADRESOURCE;
 
   if (!buffer)
     return PP_ERROR_BADARGUMENT;  // Must specify an output buffer.
-  if (object->current_read_callback_.func)
+  if (loader_object->current_read_callback_.func)
     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;
 
-  object->current_read_callback_ = callback;
-  object->current_read_buffer_ = buffer;
+  loader_object->current_read_callback_ = callback;
+  loader_object->current_read_buffer_ = buffer;
 
   dispatcher->Send(new PpapiHostMsg_PPBURLLoader_ReadResponseBody(
-      INTERFACE_ID_PPB_URL_LOADER, loader_id, bytes_to_read));
+      INTERFACE_ID_PPB_URL_LOADER, loader_object->instance(),
+      loader_object->host_resource(), bytes_to_read));
   return PP_ERROR_WOULDBLOCK;
 }
 
 int32_t FinishStreamingToFile(PP_Resource loader_id,
                               PP_CompletionCallback callback) {
-  PluginDispatcher* dispatcher = DispatcherFromURLLoader(loader_id);
-  if (!dispatcher)
+  URLLoader* loader_object;
+  PluginDispatcher* dispatcher;
+  if (!RoutingDataFromURLLoader(loader_id, &loader_object, &dispatcher))
     return PP_ERROR_BADRESOURCE;
 
   dispatcher->Send(new PpapiHostMsg_PPBURLLoader_FinishStreamingToFile(
-      INTERFACE_ID_PPB_URL_LOADER, loader_id,
+      INTERFACE_ID_PPB_URL_LOADER, loader_object->host_resource(),
       dispatcher->callback_tracker().SendCallback(callback)));
   return PP_ERROR_WOULDBLOCK;
 }
 
 void Close(PP_Resource loader_id) {
-  PluginDispatcher* dispatcher = DispatcherFromURLLoader(loader_id);
-  if (!dispatcher)
+  URLLoader* loader_object;
+  PluginDispatcher* dispatcher;
+  if (!RoutingDataFromURLLoader(loader_id, &loader_object, &dispatcher))
     return;
 
   dispatcher->Send(new PpapiHostMsg_PPBURLLoader_Close(
-      INTERFACE_ID_PPB_URL_LOADER, loader_id));
+      INTERFACE_ID_PPB_URL_LOADER, loader_object->host_resource()));
 }
 
 const PPB_URLLoader ppb_urlloader = {
   &Create,
   &IsURLLoader,
   &Open,
   &FollowRedirect,
   &GetUploadProgress,
   &GetDownloadProgress,
   &GetResponseInfo,
   &ReadResponseBody,
   &FinishStreamingToFile,
   &Close
 };
 
 // Plugin URLLoaderTrusted implementation --------------------------------------
 
-void GrantUniversalAccess(PP_Resource loader) {
-  PluginDispatcher::Get()->Send(
+void GrantUniversalAccess(PP_Resource loader_id) {
+  URLLoader* loader_object;
+  PluginDispatcher* dispatcher;
+  if (!RoutingDataFromURLLoader(loader_id, &loader_object, &dispatcher))
+    return;
+
+  dispatcher->Send(
       new PpapiHostMsg_PPBURLLoaderTrusted_GrantUniversalAccess(
-          INTERFACE_ID_PPB_URL_LOADER_TRUSTED, loader));
+          INTERFACE_ID_PPB_URL_LOADER_TRUSTED, loader_object->host_resource()));
 }
 
 const PPB_URLLoaderTrusted ppb_urlloader_trusted = {
   &GrantUniversalAccess,
   NULL,  // RegisterStatusCallback is used internally by the proxy only.
 };
 
 }  // namespace
 
 // PPB_URLLoader_Proxy ---------------------------------------------------------
 
 struct PPB_URLLoader_Proxy::ReadCallbackInfo {
-  PP_Resource pp_resource;
+  PP_Instance instance;
+  SerializedResource resource;
   std::string read_buffer;
 };
 
 PPB_URLLoader_Proxy::PPB_URLLoader_Proxy(Dispatcher* dispatcher,
                                          const void* target_interface)
     : InterfaceProxy(dispatcher, target_interface),
       callback_factory_(ALLOW_THIS_IN_INITIALIZER_LIST(this)) {
 }
 
 PPB_URLLoader_Proxy::~PPB_URLLoader_Proxy() {
 }
 
 // static
-void PPB_URLLoader_Proxy::TrackPluginResource(PP_Instance instance,
-                                              PP_Resource url_loader_resource) {
-  linked_ptr<URLLoader> object(new URLLoader(instance));
-  PluginResourceTracker::GetInstance()->AddResource(url_loader_resource,
-                                                    object);
+PP_Resource PPB_URLLoader_Proxy::TrackPluginResource(
+    PP_Instance instance,
+    SerializedResource url_loader_resource) {
+  linked_ptr<URLLoader> object(new URLLoader(instance, url_loader_resource));
+  return PluginResourceTracker::GetInstance()->AddResource(object);
 }
 
 const void* PPB_URLLoader_Proxy::GetSourceInterface() const {
   return &ppb_urlloader;
 }
 
 InterfaceID PPB_URLLoader_Proxy::GetInterfaceId() const {
   return INTERFACE_ID_PPB_URL_LOADER;
 }
 
@@ skipping 19 matching lines @@
                         OnMsgUpdateProgress)
     IPC_MESSAGE_HANDLER(PpapiMsg_PPBURLLoader_ReadResponseBody_Ack,
                         OnMsgReadResponseBodyAck)
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
   // TODO(brettw) handle bad messages!
   return handled;
 }
 
 void PPB_URLLoader_Proxy::OnMsgCreate(PP_Instance instance,
-                                      PP_Resource* result) {
-  *result = ppb_url_loader_target()->Create(instance);
+                                      SerializedResource* result) {
+  result->set_host_resource(ppb_url_loader_target()->Create(instance));
 }
 
-void PPB_URLLoader_Proxy::OnMsgOpen(PP_Resource loader,
-                                    PP_Resource request_info,
+void PPB_URLLoader_Proxy::OnMsgOpen(SerializedResource loader,
+                                    SerializedResource request_info,
                                     uint32_t serialized_callback) {
   PP_CompletionCallback callback = ReceiveCallback(serialized_callback);
   int32_t result = ppb_url_loader_target()->Open(
-      loader, request_info, callback);
+      loader.host_resource(), request_info.host_resource(), callback);
   if (result != PP_ERROR_WOULDBLOCK)
     PP_RunCompletionCallback(&callback, result);
 }
 
 void PPB_URLLoader_Proxy::OnMsgFollowRedirect(
-    PP_Resource loader,
+    SerializedResource loader,
     uint32_t serialized_callback) {
   PP_CompletionCallback callback = ReceiveCallback(serialized_callback);
   int32_t result = ppb_url_loader_target()->FollowRedirect(
-      loader, callback);
+      loader.host_resource(), callback);
   if (result != PP_ERROR_WOULDBLOCK)
     PP_RunCompletionCallback(&callback, result);
 }
 
-void PPB_URLLoader_Proxy::OnMsgGetResponseInfo(PP_Resource loader,
-                                               PP_Resource* result) {
-  *result = ppb_url_loader_target()->GetResponseInfo(loader);
+void PPB_URLLoader_Proxy::OnMsgGetResponseInfo(SerializedResource loader,
+                                               SerializedResource* result) {
+  result->set_host_resource(
+      ppb_url_loader_target()->GetResponseInfo(loader.host_resource()));
 }
 
 void PPB_URLLoader_Proxy::OnMsgReadResponseBody(
-    PP_Resource loader,
+    PP_Instance instance,
+    SerializedResource loader,
     int32_t bytes_to_read) {
   // The plugin could be sending us malicious messages, don't accept negative
   // sizes.
   if (bytes_to_read < 0) {
     // TODO(brettw) kill plugin.
     bytes_to_read = 0;
   }
 
   // This heap object will get deleted by the callback handler.
   // TODO(brettw) this will be leaked if the plugin closes the resource!
   // (Also including the plugin unloading and having the resource implicitly
   // destroyed. Depending on the cleanup ordering, we may not need the weak
   // pointer here.)
   ReadCallbackInfo* info = new ReadCallbackInfo;
-  info->pp_resource = loader;
+  info->instance = instance;
+  info->resource = loader;
+  // TODO(brettw) have a way to check for out-of-memory.
   info->read_buffer.resize(bytes_to_read);
 
   CompletionCallback callback = callback_factory_.NewCallback(
       &PPB_URLLoader_Proxy::OnReadCallback, info);
 
   int32_t result = ppb_url_loader_target()->ReadResponseBody(
-      loader, const_cast<char*>(info->read_buffer.c_str()), bytes_to_read,
-      callback.pp_completion_callback());
+      loader.host_resource(), const_cast<char*>(info->read_buffer.c_str()),
+      bytes_to_read, callback.pp_completion_callback());
   if (result != PP_ERROR_WOULDBLOCK) {
     // Send error (or perhaps success for synchronous reads) back to plugin.
     // The callback function is already set up to do this and also delete the
     // callback info.
     callback.Run(result);
   }
 }
 
 void PPB_URLLoader_Proxy::OnMsgFinishStreamingToFile(
-    PP_Resource loader,
+    SerializedResource loader,
     uint32_t serialized_callback) {
   PP_CompletionCallback callback = ReceiveCallback(serialized_callback);
   int32_t result = ppb_url_loader_target()->FinishStreamingToFile(
-      loader, callback);
+      loader.host_resource(), callback);
   if (result != PP_ERROR_WOULDBLOCK)
     PP_RunCompletionCallback(&callback, result);
 }
 
-void PPB_URLLoader_Proxy::OnMsgClose(PP_Resource loader) {
-  ppb_url_loader_target()->Close(loader);
+void PPB_URLLoader_Proxy::OnMsgClose(SerializedResource loader) {
+  ppb_url_loader_target()->Close(loader.host_resource());
 }
 
+// Called in the Plugin.
 void PPB_URLLoader_Proxy::OnMsgUpdateProgress(
-    PP_Resource resource,
-    int64_t bytes_sent,
-    int64_t total_bytes_to_be_sent,
-    int64_t bytes_received,
-    int64_t total_bytes_to_be_received) {
-  URLLoader* object = PluginResource::GetAs<URLLoader>(resource);
-  if (!object) {
-    NOTREACHED();
+    const PPBURLLoader_UpdateProgress_Params& params) {
+  PP_Resource plugin_resource =
+      PluginResourceTracker::GetInstance()->PluginResourceForHostResource(
+          params.instance, params.resource);
+  if (!plugin_resource)
     return;
-  }
+  URLLoader* object = PluginResource::GetAs<URLLoader>(plugin_resource);
+  if (!object)
+    return;
 
-  object->bytes_sent_ = bytes_sent;
-  object->total_bytes_to_be_sent_ = total_bytes_to_be_sent;
-  object->bytes_received_ = bytes_received;
-  object->total_bytes_to_be_received_ = total_bytes_to_be_received;
+  object->bytes_sent_ = params.bytes_sent;
+  object->total_bytes_to_be_sent_ = params.total_bytes_to_be_sent;
+  object->bytes_received_ = params.bytes_received;
+  object->total_bytes_to_be_received_ = params.total_bytes_to_be_received;
 }
 
-void PPB_URLLoader_Proxy::OnMsgReadResponseBodyAck(PP_Resource pp_resource,
-                                                   int32 result,
-                                                   const std::string& data) {
-  URLLoader* object = PluginResource::GetAs<URLLoader>(pp_resource);
-  if (!object) {
-    NOTREACHED();
+// Called in the Plugin.
+void PPB_URLLoader_Proxy::OnMsgReadResponseBodyAck(
+    PP_Instance instance,
+    SerializedResource host_resource,
+    int32 result,
+    const std::string& data) {
+  PP_Resource plugin_resource =
+      PluginResourceTracker::GetInstance()->PluginResourceForHostResource(
+          instance, host_resource);
+  if (!plugin_resource)
     return;
-  }
+  URLLoader* object = PluginResource::GetAs<URLLoader>(plugin_resource);
+  if (!object)
+    return;
 
   if (!object->current_read_callback_.func || !object->current_read_buffer_) {
     NOTREACHED();
     return;
   }
 
   // In the error case, the string will be empty, so we can always just copy
   // out of it before issuing the callback.
   memcpy(object->current_read_buffer_, data.c_str(), data.length());
 
   // The plugin should be able to make a new request from their callback, so
   // we have to clear our copy first.
   PP_CompletionCallback temp_callback = object->current_read_callback_;
   object->current_read_callback_ = PP_BlockUntilComplete();
   object->current_read_buffer_ = NULL;
   PP_RunCompletionCallback(&temp_callback, result);
 }
 
 void PPB_URLLoader_Proxy::OnReadCallback(int32_t result,
                                          ReadCallbackInfo* info) {
   int32_t bytes_read = 0;
   if (result > 0)
     bytes_read = result;  // Positive results indicate bytes read.
   info->read_buffer.resize(bytes_read);
 
   dispatcher()->Send(new PpapiMsg_PPBURLLoader_ReadResponseBody_Ack(
-      INTERFACE_ID_PPB_URL_LOADER, info->pp_resource,
+      INTERFACE_ID_PPB_URL_LOADER, info->instance, info->resource,
       result, info->read_buffer));
 
   delete info;
 }
 
 // PPB_URLLoaderTrusted_Proxy --------------------------------------------------
 
 PPB_URLLoaderTrusted_Proxy::PPB_URLLoaderTrusted_Proxy(
     Dispatcher* dispatcher,
     const void* target_interface)
@@ skipping 15 matching lines @@
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(PPB_URLLoaderTrusted_Proxy, msg)
     IPC_MESSAGE_HANDLER(PpapiHostMsg_PPBURLLoaderTrusted_GrantUniversalAccess,
                         OnMsgGrantUniversalAccess)
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP();
   // TODO(brettw) handle bad messages!
   return handled;
 }
 
-void PPB_URLLoaderTrusted_Proxy::OnMsgGrantUniversalAccess(PP_Resource loader) {
-  ppb_url_loader_trusted_target()->GrantUniversalAccess(loader);
+void PPB_URLLoaderTrusted_Proxy::OnMsgGrantUniversalAccess(
+    SerializedResource loader) {
+  ppb_url_loader_trusted_target()->GrantUniversalAccess(loader.host_resource());
 }
 
 }  // namespace proxy
 }  // namespace pp