Request text context in the plugin process

webkit/plugins/ppapi/ppapi_plugin_instance.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 "webkit/plugins/ppapi/ppapi_plugin_instance.h"
 
 #include "base/bind.h"
 #include "base/debug/trace_event.h"
 #include "base/logging.h"
 #include "base/memory/linked_ptr.h"
@@ skipping 139 matching lines @@
 
 namespace {
 
 // The default text input type is to regard the plugin always accept text input.
 // This is for allowing users to use input methods even on completely-IME-
 // unaware plugins (e.g., PPAPI Flash or PDF plugin for M16).
 // Plugins need to explicitly opt out the text input mode if they know
 // that they don't accept texts.
 const ui::TextInputType kPluginDefaultTextInputType = ui::TEXT_INPUT_TYPE_TEXT;
 
-// The length of text to request as a surrounding context of selection.
-// For now, the value is copied from the one with render_view_impl.cc.
-// TODO(kinaba) implement a way to dynamically sync the requirement.
-static const size_t kExtraCharsBeforeAndAfterSelection = 100;
-
 #define COMPILE_ASSERT_MATCHING_ENUM(webkit_name, np_name) \
     COMPILE_ASSERT(static_cast<int>(WebCursorInfo::webkit_name) \
                        == static_cast<int>(np_name), \
                    mismatching_enums)
 
 // <embed>/<object> attributes.
 const char kWidth[] = "width";
 const char kHeight[] = "height";
 const char kBorder[] = "border";  // According to w3c, deprecated.
 const char kStyle[] = "style";
@@ skipping 428 matching lines @@
 
 void PluginInstance::SetTextInputType(ui::TextInputType type) {
   text_input_type_ = type;
   delegate()->PluginTextInputTypeChanged(this);
 }
 
 void PluginInstance::SelectionChanged() {
   // TODO(kinaba): currently the browser always calls RequestSurroundingText.
   // It can be optimized so that it won't call it back until the information
   // is really needed.
-  RequestSurroundingText(kExtraCharsBeforeAndAfterSelection);
+
+  // Avoid calling in nested context or else this will reenter the plugin. This
+  // uses a weak pointer rather than exploiting the fact that this class is
+  // refcounted because we don't actually want this operation to affect the
+  // lifetime of the instance.
+  MessageLoop::current()->PostTask(FROM_HERE,
+      base::Bind(&PluginInstance::RequestSurroundingText,
+                 AsWeakPtr(),
+                 static_cast<size_t>(kExtraCharsForTextInput)));
 }
 
 void PluginInstance::UpdateSurroundingText(const std::string& text,
                                            size_t caret, size_t anchor) {
   surrounding_text_ = text;
   selection_caret_ = caret;
   selection_anchor_ = anchor;
   delegate()->PluginSelectionChanged(this);
 }
 
@@ skipping 268 matching lines @@
   PP_Var rv = plugin_pdf_interface_->GetLinkAtPosition(pp_instance(), p);
   StringVar* string = StringVar::FromPPVar(rv);
   string16 link;
   if (string)
     link = UTF8ToUTF16(string->value());
   // Release the ref the plugin transfered to us.
   PpapiGlobals::Get()->GetVarTracker()->ReleaseVar(rv);
   return link;
 }
 
-bool PluginInstance::RequestSurroundingText(
+void PluginInstance::RequestSurroundingText(
     size_t desired_number_of_characters) {
   // Keep a reference on the stack. See NOTE above.
   scoped_refptr<PluginInstance> ref(this);
   if (!LoadTextInputInterface())
-    return false;
+    return;
   plugin_textinput_interface_->RequestSurroundingText(
       pp_instance(), desired_number_of_characters);
-  return true;
 }
 
 void PluginInstance::Zoom(double factor, bool text_only) {
   // Keep a reference on the stack. See NOTE above.
   scoped_refptr<PluginInstance> ref(this);
   if (!LoadZoomInterface())
     return;
   plugin_zoom_interface_->Zoom(pp_instance(), factor, PP_FromBool(text_only));
 }
 
@@ skipping 1251 matching lines @@
   screen_size_for_fullscreen_ = gfx::Size();
   WebElement element = container_->element();
   element.setAttribute(WebString::fromUTF8(kWidth), width_before_fullscreen_);
   element.setAttribute(WebString::fromUTF8(kHeight), height_before_fullscreen_);
   element.setAttribute(WebString::fromUTF8(kBorder), border_before_fullscreen_);
   element.setAttribute(WebString::fromUTF8(kStyle), style_before_fullscreen_);
 }
 
 }  // namespace ppapi
 }  // namespace webkit