Make BrowserAccessibilityManager cross platform. Step 1....

chrome/browser/browser_accessibility_win.h

-// 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.
-
-#ifndef CHROME_BROWSER_BROWSER_ACCESSIBILITY_WIN_H_
-#define CHROME_BROWSER_BROWSER_ACCESSIBILITY_WIN_H_
-#pragma once
-
-#include <atlbase.h>
-#include <atlcom.h>
-#include <oleacc.h>
-
-#include <map>
-#include <vector>
-
-#include "chrome/browser/browser_accessibility_manager_win.h"
-#include "ia2_api_all.h"  // Generated
-#include "ISimpleDOMDocument.h"  // Generated
-#include "ISimpleDOMNode.h"  // Generated
-#include "ISimpleDOMText.h"  // Generated
-#include "webkit/glue/webaccessibility.h"
-
-using webkit_glue::WebAccessibility;
-
-////////////////////////////////////////////////////////////////////////////////
-//
-// BrowserAccessibility
-//
-// Class implementing the MSAA IAccessible COM interface for the
-// Browser-Renderer communication of MSAA information, providing accessibility
-// to be used by screen readers and other assistive technology (AT).
-//
-////////////////////////////////////////////////////////////////////////////////
-class ATL_NO_VTABLE BrowserAccessibility
-  : public CComObjectRootEx<CComMultiThreadModel>,
-    public IDispatchImpl<IAccessible2, &IID_IAccessible2,
-                         &LIBID_IAccessible2Lib>,
-    public IAccessibleImage,
-    public IAccessibleText,
-    public IServiceProvider,
-    public ISimpleDOMDocument,
-    public ISimpleDOMNode,
-    public ISimpleDOMText {
- public:
-  BEGIN_COM_MAP(BrowserAccessibility)
-    COM_INTERFACE_ENTRY2(IDispatch, IAccessible2)
-    COM_INTERFACE_ENTRY2(IAccessible, IAccessible2)
-    COM_INTERFACE_ENTRY(IAccessible2)
-    COM_INTERFACE_ENTRY(IAccessibleImage)
-    COM_INTERFACE_ENTRY(IAccessibleText)
-    COM_INTERFACE_ENTRY(IServiceProvider)
-    COM_INTERFACE_ENTRY(ISimpleDOMDocument)
-    COM_INTERFACE_ENTRY(ISimpleDOMNode)
-    COM_INTERFACE_ENTRY(ISimpleDOMText)
-  END_COM_MAP()
-
-  BrowserAccessibility();
-
-  virtual ~BrowserAccessibility();
-
-  // Initialize this object and mark it as active.
-  void Initialize(BrowserAccessibilityManager* manager,
-                  BrowserAccessibility* parent,
-                  LONG child_id,
-                  LONG index_in_parent,
-                  const webkit_glue::WebAccessibility& src);
-
-  // Add a child of this object.
-  void AddChild(BrowserAccessibility* child);
-
-  // Mark this object as inactive, and remove references to all children.
-  // When no other clients hold any references to this object it will be
-  // deleted, and in the meantime, calls to any methods will return E_FAIL.
-  void InactivateTree();
-
-  // Return true if this object is equal to or a descendant of |ancestor|.
-  bool IsDescendantOf(BrowserAccessibility* ancestor);
-
-  // Returns the parent of this object, or NULL if it's the BrowserAccessibility
-  // root.
-  BrowserAccessibility* GetParent();
-
-  // Returns the number of children of this BrowserAccessibility object.
-  uint32 GetChildCount();
-
-  // Return the previous sibling of this object, or NULL if it's the first
-  // child of its parent.
-  BrowserAccessibility* GetPreviousSibling();
-
-  // Return the next sibling of this object, or NULL if it's the last child
-  // of its parent.
-  BrowserAccessibility* GetNextSibling();
-
-  // Replace a child BrowserAccessibility object. Used when updating the
-  // accessibility tree.
-  void ReplaceChild(
-      const BrowserAccessibility* old_acc, BrowserAccessibility* new_acc);
-
-  // Accessors
-  LONG child_id() const { return child_id_; }
-  int32 renderer_id() const { return renderer_id_; }
-  LONG index_in_parent() const { return index_in_parent_; }
-
-  // Add one to the reference count and return the same object. Always
-  // use this method when returning a BrowserAccessibility object as
-  // an output parameter to a COM interface, never use it otherwise.
-  BrowserAccessibility* NewReference();
-
-  //
-  // IAccessible methods.
-  //
-
-  // Performs the default action on a given object.
-  STDMETHODIMP accDoDefaultAction(VARIANT var_id);
-
-  // Retrieves the child element or child object at a given point on the screen.
-  STDMETHODIMP accHitTest(LONG x_left, LONG y_top, VARIANT* child);
-
-  // Retrieves the specified object's current screen location.
-  STDMETHODIMP accLocation(LONG* x_left,
-                           LONG* y_top,
-                           LONG* width,
-                           LONG* height,
-                           VARIANT var_id);
-
-  // Traverses to another UI element and retrieves the object.
-  STDMETHODIMP accNavigate(LONG nav_dir, VARIANT start, VARIANT* end);
-
-  // Retrieves an IDispatch interface pointer for the specified child.
-  STDMETHODIMP get_accChild(VARIANT var_child, IDispatch** disp_child);
-
-  // Retrieves the number of accessible children.
-  STDMETHODIMP get_accChildCount(LONG* child_count);
-
-  // Retrieves a string that describes the object's default action.
-  STDMETHODIMP get_accDefaultAction(VARIANT var_id, BSTR* default_action);
-
-  // Retrieves the object's description.
-  STDMETHODIMP get_accDescription(VARIANT var_id, BSTR* desc);
-
-  // Retrieves the object that has the keyboard focus.
-  STDMETHODIMP get_accFocus(VARIANT* focus_child);
-
-  // Retrieves the help information associated with the object.
-  STDMETHODIMP get_accHelp(VARIANT var_id, BSTR* help);
-
-  // Retrieves the specified object's shortcut.
-  STDMETHODIMP get_accKeyboardShortcut(VARIANT var_id, BSTR* access_key);
-
-  // Retrieves the name of the specified object.
-  STDMETHODIMP get_accName(VARIANT var_id, BSTR* name);
-
-  // Retrieves the IDispatch interface of the object's parent.
-  STDMETHODIMP get_accParent(IDispatch** disp_parent);
-
-  // Retrieves information describing the role of the specified object.
-  STDMETHODIMP get_accRole(VARIANT var_id, VARIANT* role);
-
-  // Retrieves the current state of the specified object.
-  STDMETHODIMP get_accState(VARIANT var_id, VARIANT* state);
-
-  // Returns the value associated with the object.
-  STDMETHODIMP get_accValue(VARIANT var_id, BSTR* value);
-
-  // Make an object take focus or extend the selection.
-  STDMETHODIMP accSelect(LONG flags_sel, VARIANT var_id);
-
-  STDMETHODIMP get_accHelpTopic(BSTR* help_file,
-                                VARIANT var_id,
-                                LONG* topic_id);
-
-  STDMETHODIMP get_accSelection(VARIANT* selected);
-
-  // Deprecated methods, not implemented.
-  STDMETHODIMP put_accName(VARIANT var_id, BSTR put_name) {
-    return E_NOTIMPL;
-  }
-  STDMETHODIMP put_accValue(VARIANT var_id, BSTR put_val) {
-    return E_NOTIMPL;
-  }
-
-  //
-  // IAccessible2 methods.
-  //
-
-  // Returns role from a longer list of possible roles.
-  STDMETHODIMP role(LONG* role);
-
-  // Returns the state bitmask from a larger set of possible states.
-  STDMETHODIMP get_states(AccessibleStates* states);
-
-  // Returns the attributes specific to this IAccessible2 object,
-  // such as a cell's formula.
-  STDMETHODIMP get_attributes(BSTR* attributes);
-
-  // Get the unique ID of this object so that the client knows if it's
-  // been encountered previously.
-  STDMETHODIMP get_uniqueID(LONG* unique_id);
-
-  // Get the window handle of the enclosing window.
-  STDMETHODIMP get_windowHandle(HWND* window_handle);
-
-  // Get this object's index in its parent object.
-  STDMETHODIMP get_indexInParent(LONG* index_in_parent);
-
-  // IAccessible2 methods not implemented.
-  STDMETHODIMP get_extendedRole(BSTR* extended_role) {
-    return E_NOTIMPL;
-  }
-  STDMETHODIMP get_nRelations(LONG* n_relations) {
-    return E_NOTIMPL;
-  }
-  STDMETHODIMP get_relation(LONG relation_index,
-                            IAccessibleRelation** relation) {
-    return E_NOTIMPL;
-  }
-  STDMETHODIMP get_relations(LONG max_relations,
-                             IAccessibleRelation** relations,
-                             LONG* n_relations) {
-    return E_NOTIMPL;
-  }
-  STDMETHODIMP scrollTo(enum IA2ScrollType scroll_type) {
-    return E_NOTIMPL;
-  }
-  STDMETHODIMP scrollToPoint(enum IA2CoordinateType coordinate_type,
-                             LONG x,
-                             LONG y) {
-    return E_NOTIMPL;
-  }
-  STDMETHODIMP get_groupPosition(LONG* group_level,
-                                 LONG* similar_items_in_group,
-                                 LONG* position_in_group) {
-    return E_NOTIMPL;
-  }
-  STDMETHODIMP get_localizedExtendedRole(BSTR* localized_extended_role) {
-    return E_NOTIMPL;
-  }
-  STDMETHODIMP get_nExtendedStates(LONG* n_extended_states) {
-    return E_NOTIMPL;
-  }
-  STDMETHODIMP get_extendedStates(LONG max_extended_states,
-                                  BSTR** extended_states,
-                                  LONG* n_extended_states) {
-    return E_NOTIMPL;
-  }
-  STDMETHODIMP get_localizedExtendedStates(LONG max_localized_extended_states,
-                                           BSTR** localized_extended_states,
-                                           LONG* n_localized_extended_states) {
-    return E_NOTIMPL;
-  }
-  STDMETHODIMP get_locale(IA2Locale* locale) {
-    return E_NOTIMPL;
-  }
-
-  //
-  // IAccessibleImage methods.
-  //
-
-  STDMETHODIMP get_description(BSTR* description);
-
-  STDMETHODIMP get_imagePosition(enum IA2CoordinateType coordinate_type,
-                                 long* x, long* y);
-
-  STDMETHODIMP get_imageSize(long* height, long* width);
-
-  //
-  // IAccessibleText methods.
-  //
-
-  STDMETHODIMP get_nCharacters(long* n_characters);
-
-  STDMETHODIMP get_text(long start_offset, long end_offset, BSTR* text);
-
-  STDMETHODIMP get_caretOffset(long* offset);
-
-  // IAccessibleText methods not implemented.
-  STDMETHODIMP addSelection(long start_offset, long end_offset) {
-    return E_NOTIMPL;
-  }
-  STDMETHODIMP get_attributes(long offset, long* start_offset, long* end_offset,
-                              BSTR* text_attributes) {
-    return E_NOTIMPL;
-  }
-  STDMETHODIMP get_characterExtents(long offset,
-                                    enum IA2CoordinateType coord_type,
-                                    long* x, long* y,
-                                    long* width, long* height) {
-    return E_NOTIMPL;
-  }
-  STDMETHODIMP get_nSelections(long* n_selections) {
-    return E_NOTIMPL;
-  }
-  STDMETHODIMP get_offsetAtPoint(long x, long y,
-                             enum IA2CoordinateType coord_type,
-                             long* offset) {
-    return E_NOTIMPL;
-  }
-  STDMETHODIMP get_selection(long selection_index,
-                         long* start_offset,
-                         long* end_offset) {
-    return E_NOTIMPL;
-  }
-  STDMETHODIMP get_textBeforeOffset(long offset,
-                                enum IA2TextBoundaryType boundary_type,
-                                long* start_offset, long* end_offset,
-                                BSTR* text) {
-    return E_NOTIMPL;
-  }
-  STDMETHODIMP get_textAfterOffset(long offset,
-                               enum IA2TextBoundaryType boundary_type,
-                               long* start_offset, long* end_offset,
-                               BSTR* text) {
-    return E_NOTIMPL;
-  }
-  STDMETHODIMP get_textAtOffset(long offset,
-                            enum IA2TextBoundaryType boundary_type,
-                            long* start_offset, long* end_offset,
-                            BSTR* text) {
-    return E_NOTIMPL;
-  }
-  STDMETHODIMP removeSelection(long selection_index) {
-    return E_NOTIMPL;
-  }
-  STDMETHODIMP setCaretOffset(long offset) {
-    return E_NOTIMPL;
-  }
-  STDMETHODIMP setSelection(long selection_index,
-                            long start_offset,
-                            long end_offset) {
-    return E_NOTIMPL;
-  }
-  STDMETHODIMP scrollSubstringTo(long start_index,
-                                 long end_index,
-                                 enum IA2ScrollType scroll_type) {
-    return E_NOTIMPL;
-  }
-  STDMETHODIMP scrollSubstringToPoint(long start_index, long end_index,
-                                      enum IA2CoordinateType coordinate_type,
-                                      long x, long y) {
-    return E_NOTIMPL;
-  }
-  STDMETHODIMP get_newText(IA2TextSegment* new_text) {
-    return E_NOTIMPL;
-  }
-  STDMETHODIMP get_oldText(IA2TextSegment* old_text) {
-    return E_NOTIMPL;
-  }
-
-  //
-  // ISimpleDOMDocument methods.
-  //
-
-  STDMETHODIMP get_URL(BSTR* url);
-
-  STDMETHODIMP get_title(BSTR* title);
-
-  STDMETHODIMP get_mimeType(BSTR* mime_type);
-
-  STDMETHODIMP get_docType(BSTR* doc_type);
-
-  STDMETHODIMP get_nameSpaceURIForID(
-      short name_space_id, BSTR *name_space_uri) {
-    return E_NOTIMPL;
-  }
-  STDMETHODIMP put_alternateViewMediaTypes(
-      BSTR *comma_separated_media_types) {
-    return E_NOTIMPL;
-  }
-
-  //
-  // ISimpleDOMNode methods.
-  //
-
-  STDMETHODIMP get_nodeInfo(
-      BSTR* node_name,
-      short* name_space_id,
-      BSTR* node_value,
-      unsigned int* num_children,
-      unsigned int* unique_id,
-      unsigned short* node_type);
-
-  STDMETHODIMP get_attributes(
-      unsigned short max_attribs,
-      BSTR* attrib_names,
-      short* name_space_id,
-      BSTR* attrib_values,
-      unsigned short* num_attribs);
-
-  STDMETHODIMP get_attributesForNames(
-      unsigned short num_attribs,
-      BSTR* attrib_names,
-      short* name_space_id,
-      BSTR* attrib_values);
-
-  STDMETHODIMP get_computedStyle(
-      unsigned short max_style_properties,
-      boolean use_alternate_view,
-      BSTR *style_properties,
-      BSTR *style_values,
-      unsigned short *num_style_properties);
-
-  STDMETHODIMP get_computedStyleForProperties(
-      unsigned short num_style_properties,
-      boolean use_alternate_view,
-      BSTR* style_properties,
-      BSTR* style_values);
-
-  STDMETHODIMP scrollTo(boolean placeTopLeft);
-
-  STDMETHODIMP get_parentNode(ISimpleDOMNode** node);
-
-  STDMETHODIMP get_firstChild(ISimpleDOMNode** node);
-
-  STDMETHODIMP get_lastChild(ISimpleDOMNode** node);
-
-  STDMETHODIMP get_previousSibling(ISimpleDOMNode** node);
-
-  STDMETHODIMP get_nextSibling(ISimpleDOMNode** node);
-
-  STDMETHODIMP get_childAt(
-      unsigned int child_index,
-      ISimpleDOMNode** node);
-
-  STDMETHODIMP get_innerHTML(BSTR* innerHTML) {
-    return E_NOTIMPL;
-  }
-
-  STDMETHODIMP get_localInterface(void** local_interface) {
-    return E_NOTIMPL;
-  }
-
-  STDMETHODIMP get_language(BSTR* language) {
-    return E_NOTIMPL;
-  }
-
-  //
-  // ISimpleDOMText methods.
-  //
-
-  STDMETHODIMP get_domText(BSTR* dom_text);
-
-  STDMETHODIMP get_clippedSubstringBounds(
-      unsigned int start_index,
-      unsigned int end_index,
-      int* x,
-      int* y,
-      int* width,
-      int* height) {
-    return E_NOTIMPL;
-  }
-
-  STDMETHODIMP get_unclippedSubstringBounds(
-      unsigned int start_index,
-      unsigned int end_index,
-      int* x,
-      int* y,
-      int* width,
-      int* height) {
-    return E_NOTIMPL;
-  }
-
-  STDMETHODIMP scrollToSubstring(
-      unsigned int start_index,
-      unsigned int end_index)  {
-    return E_NOTIMPL;
-  }
-
-  STDMETHODIMP get_fontFamily(BSTR *font_family)  {
-    return E_NOTIMPL;
-  }
-
-  //
-  // IServiceProvider methods.
-  //
-
-  STDMETHODIMP QueryService(REFGUID guidService, REFIID riid, void** object);
-
-  //
-  // CComObjectRootEx methods.
-  //
-
-  HRESULT WINAPI InternalQueryInterface(void* this_ptr,
-                                        const _ATL_INTMAP_ENTRY* entries,
-                                        REFIID iid,
-                                        void** object);
-
- private:
-  // Many MSAA methods take a var_id parameter indicating that the operation
-  // should be performed on a particular child ID, rather than this object.
-  // This method tries to figure out the target object from |var_id| and
-  // returns a pointer to the target object if it exists, otherwise NULL.
-  // Does not return a new reference.
-  BrowserAccessibility* GetTargetFromChildID(const VARIANT& var_id);
-
-  // Initialize the role and state metadata from the role enum and state
-  // bitmasks defined in webkit/glue/webaccessibility.h.
-  void InitRoleAndState(LONG web_accessibility_role,
-                        LONG web_accessibility_state);
-
-  // Return true if this attribute is in the attributes map.
-  bool HasAttribute(WebAccessibility::Attribute attribute);
-
-  // Retrieve the string value of an attribute from the attribute map and
-  // returns true if found.
-  bool GetAttribute(WebAccessibility::Attribute attribute, string16* value);
-
-  // Retrieve the string value of an attribute from the attribute map and
-  // if found and nonempty, allocate a new BSTR (with SysAllocString)
-  // and return S_OK. If not found or empty, return S_FALSE.
-  HRESULT GetAttributeAsBstr(
-      WebAccessibility::Attribute attribute, BSTR* value_bstr);
-
-  // Escape a string like it would be escaped for a URL or HTML form.
-  string16 Escape(string16 str);
-
-  // The manager of this tree of accessibility objects; needed for
-  // global operations like focus tracking.
-  BrowserAccessibilityManager* manager_;
-  // The parent of this object, may be NULL if we're the root object.
-  BrowserAccessibility* parent_;
-  // The ID of this object; globally unique within the browser process.
-  LONG child_id_;
-  // The index of this within its parent object.
-  LONG index_in_parent_;
-  // The ID of this object in the renderer process.
-  int32 renderer_id_;
-
-  // The children of this object.
-  std::vector<BrowserAccessibility*> children_;
-
-  // Accessibility metadata from the renderer, used to respond to MSAA
-  // events.
-  string16 name_;
-  string16 value_;
-  std::map<int32, string16> attributes_;
-  std::vector<std::pair<string16, string16> > html_attributes_;
-
-  LONG role_;
-  LONG state_;
-  string16 role_name_;
-  LONG ia2_role_;
-  LONG ia2_state_;
-  WebKit::WebRect location_;
-
-  // COM objects are reference-counted. When we're done with this object
-  // and it's removed from our accessibility tree, a client may still be
-  // holding onto a pointer to this object, so we mark it as inactive
-  // so that calls to any of this object's methods immediately return
-  // failure.
-  bool instance_active_;
-
-  DISALLOW_COPY_AND_ASSIGN(BrowserAccessibility);
-};
-
-#endif  // CHROME_BROWSER_BROWSER_ACCESSIBILITY_WIN_H_