Add initial GTK web accessibility framework (third attempt).

content/browser/accessibility/browser_accessibility_gtk.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/accessibility/browser_accessibility_gtk.h"
+
+#include <gtk/gtk.h>
+
+#include "base/utf_string_conversions.h"
+#include "content/browser/accessibility/browser_accessibility_manager_gtk.h"
+#include "content/common/accessibility_messages.h"
+
+using webkit_glue::WebAccessibility;
+
+// The maximum length of an autogenerated unique type name string,
+// generated from the 16-bit interface mask from an AtkObject.
+// 30 is enough for the prefix "WAIType" + 5 hex chars (max) */
+static const int kWAITypeNameLen = 30;
+
+static gpointer browser_accessibility_parent_class = NULL;
+
+static BrowserAccessibilityGtk* ToBrowserAccessibilityGtk(
+    BrowserAccessibilityAtk* atk_object) {
+  if (!atk_object)
+    return NULL;
+
+  return atk_object->m_object;
+}
+
+static BrowserAccessibilityGtk* ToBrowserAccessibilityGtk(
+    AtkObject* atk_object) {
+  if (!IS_BROWSER_ACCESSIBILITY(atk_object))
+    return NULL;
+
+  return ToBrowserAccessibilityGtk(BROWSER_ACCESSIBILITY(atk_object));
+}
+
+static const gchar* browser_accessibility_get_name(AtkObject* atk_object) {
+  BrowserAccessibilityGtk* obj = ToBrowserAccessibilityGtk(atk_object);
+  return obj->atk_acc_name().c_str();
+}
+
+static const gchar* browser_accessibility_get_description(
+    AtkObject* atk_object) {
+  BrowserAccessibilityGtk* obj = ToBrowserAccessibilityGtk(atk_object);
+  string16 description;
+  obj->GetStringAttribute(WebAccessibility::ATTR_DESCRIPTION, &description);
+  return UTF16ToUTF8(description).c_str();
+}
+
+static AtkObject* browser_accessibility_get_parent(AtkObject* atk_object) {
+  BrowserAccessibilityGtk* obj = ToBrowserAccessibilityGtk(atk_object);
+  if (obj->parent())
+    return obj->parent()->ToBrowserAccessibilityGtk()->GetAtkObject();
+  else
+    return gtk_widget_get_accessible(obj->manager()->GetParentView());
+}
+
+static gint browser_accessibility_get_n_children(AtkObject* atk_object) {
+  BrowserAccessibilityGtk* obj = ToBrowserAccessibilityGtk(atk_object);
+  return obj->children().size();
+}
+
+static AtkObject* browser_accessibility_ref_child(
+    AtkObject* atk_object, gint index) {
+  BrowserAccessibilityGtk* obj = ToBrowserAccessibilityGtk(atk_object);
+  AtkObject* result =
+      obj->children()[index]->ToBrowserAccessibilityGtk()->GetAtkObject();
+  g_object_ref(result);
+  return result;
+}
+
+static gint browser_accessibility_get_index_in_parent(AtkObject* atk_object) {
+  BrowserAccessibilityGtk* obj = ToBrowserAccessibilityGtk(atk_object);
+  return obj->index_in_parent();
+}
+
+static AtkAttributeSet* browser_accessibility_get_attributes(
+    AtkObject* atk_object) {
+  return NULL;
+}
+
+static AtkRole browser_accessibility_get_role(AtkObject* atk_object) {
+  BrowserAccessibilityGtk* obj = ToBrowserAccessibilityGtk(atk_object);
+  return obj->atk_role();
+}
+
+static AtkStateSet* browser_accessibility_ref_state_set(AtkObject* atk_object) {
+  BrowserAccessibilityGtk* obj = ToBrowserAccessibilityGtk(atk_object);
+  AtkStateSet* state_set =
+      ATK_OBJECT_CLASS(browser_accessibility_parent_class)->
+          ref_state_set(atk_object);
+  int32 state = obj->state();
+
+  if ((state >> WebAccessibility::STATE_FOCUSABLE) & 1)
+    atk_state_set_add_state(state_set, ATK_STATE_FOCUSABLE);
+  if (obj->manager()->GetFocus(NULL) == obj)
+    atk_state_set_add_state(state_set, ATK_STATE_FOCUSED);
+
+  return state_set;
+}
+
+static AtkRelationSet* browser_accessibility_ref_relation_set(
+    AtkObject* atk_object) {
+  AtkRelationSet* relation_set =
+      ATK_OBJECT_CLASS(browser_accessibility_parent_class)
+          ->ref_relation_set(atk_object);
+  return relation_set;
+}
+
+static void browser_accessibility_init(AtkObject* atk_object, gpointer data) {
+  if (ATK_OBJECT_CLASS(browser_accessibility_parent_class)->initialize) {
+    ATK_OBJECT_CLASS(browser_accessibility_parent_class)->initialize(
+        atk_object, data);
+  }
+
+  BROWSER_ACCESSIBILITY(atk_object)->m_object =
+      reinterpret_cast<BrowserAccessibilityGtk*>(data);
+}
+
+static void browser_accessibility_finalize(GObject* atk_object) {
+  G_OBJECT_CLASS(browser_accessibility_parent_class)->finalize(atk_object);
+}
+
+static void browser_accessibility_class_init(AtkObjectClass* klass) {
+  GObjectClass* gobject_class = G_OBJECT_CLASS(klass);
+  browser_accessibility_parent_class = g_type_class_peek_parent(klass);
+
+  gobject_class->finalize = browser_accessibility_finalize;
+  klass->initialize = browser_accessibility_init;
+  klass->get_name = browser_accessibility_get_name;
+  klass->get_description = browser_accessibility_get_description;
+  klass->get_parent = browser_accessibility_get_parent;
+  klass->get_n_children = browser_accessibility_get_n_children;
+  klass->ref_child = browser_accessibility_ref_child;
+  klass->get_role = browser_accessibility_get_role;
+  klass->ref_state_set = browser_accessibility_ref_state_set;
+  klass->get_index_in_parent = browser_accessibility_get_index_in_parent;
+  klass->get_attributes = browser_accessibility_get_attributes;
+  klass->ref_relation_set = browser_accessibility_ref_relation_set;
+}
+
+GType browser_accessibility_get_type() {
+  static volatile gsize type_volatile = 0;
+
+  if (g_once_init_enter(&type_volatile)) {
+    static const GTypeInfo tinfo = {
+      sizeof(BrowserAccessibilityAtkClass),
+      (GBaseInitFunc) 0,
+      (GBaseFinalizeFunc) 0,
+      (GClassInitFunc) browser_accessibility_class_init,
+      (GClassFinalizeFunc) 0,
+      0, /* class data */
+      sizeof(BrowserAccessibilityAtk), /* instance size */
+      0, /* nb preallocs */
+      (GInstanceInitFunc) 0,
+      0 /* value table */
+    };
+
+    GType type = g_type_register_static(
+        ATK_TYPE_OBJECT, "BrowserAccessibility", &tinfo, GTypeFlags(0));
+    g_once_init_leave(&type_volatile, type);
+  }
+
+  return type_volatile;
+}
+
+static guint16 GetInterfaceMaskFromObject(BrowserAccessibilityGtk* obj) {
+  return 0;
+}
+
+static const char* GetUniqueAccessibilityTypeName(guint16 interface_mask)
+{
+  static char name[kWAITypeNameLen + 1];
+
+  sprintf(name, "WAIType%x", interface_mask);
+  name[kWAITypeNameLen] = '\0';
+
+  return name;
+}
+
+static const GInterfaceInfo AtkInterfacesInitFunctions[] = {
+};
+
+enum WAIType {
+  WAI_ACTION,
+  WAI_SELECTION,
+  WAI_EDITABLE_TEXT,
+  WAI_TEXT,
+  WAI_COMPONENT,
+  WAI_IMAGE,
+  WAI_TABLE,
+  WAI_HYPERTEXT,
+  WAI_HYPERLINK,
+  WAI_DOCUMENT,
+  WAI_VALUE,
+};
+
+static GType GetAtkInterfaceTypeFromWAIType(WAIType type) {
+  switch (type) {
+    case WAI_ACTION:
+      return ATK_TYPE_ACTION;
+    case WAI_SELECTION:
+      return ATK_TYPE_SELECTION;
+    case WAI_EDITABLE_TEXT:
+      return ATK_TYPE_EDITABLE_TEXT;
+    case WAI_TEXT:
+      return ATK_TYPE_TEXT;
+    case WAI_COMPONENT:
+      return ATK_TYPE_COMPONENT;
+    case WAI_IMAGE:
+      return ATK_TYPE_IMAGE;
+    case WAI_TABLE:
+      return ATK_TYPE_TABLE;
+    case WAI_HYPERTEXT:
+      return ATK_TYPE_HYPERTEXT;
+    case WAI_HYPERLINK:
+      return ATK_TYPE_HYPERLINK_IMPL;
+    case WAI_DOCUMENT:
+      return ATK_TYPE_DOCUMENT;
+    case WAI_VALUE:
+      return ATK_TYPE_VALUE;
+  }
+
+  return G_TYPE_INVALID;
+}
+
+static GType GetAccessibilityTypeFromObject(BrowserAccessibilityGtk* obj) {
+  static const GTypeInfo type_info = {
+    sizeof(BrowserAccessibilityAtkClass),
+    (GBaseInitFunc) 0,
+    (GBaseFinalizeFunc) 0,
+    (GClassInitFunc) 0,
+    (GClassFinalizeFunc) 0,
+    0, /* class data */
+    sizeof(BrowserAccessibilityAtk), /* instance size */
+    0, /* nb preallocs */
+    (GInstanceInitFunc) 0,
+    0 /* value table */
+  };
+
+  guint16 interface_mask = GetInterfaceMaskFromObject(obj);
+  const char* atk_type_name = GetUniqueAccessibilityTypeName(interface_mask);
+  GType type = g_type_from_name(atk_type_name);
+  if (type)
+    return type;
+
+  type = g_type_register_static(BROWSER_ACCESSIBILITY_TYPE,
+                                atk_type_name,
+                                &type_info,
+                                GTypeFlags(0));
+  for (guint i = 0; i < G_N_ELEMENTS(AtkInterfacesInitFunctions); i++) {
+    if (interface_mask & (1 << i)) {
+      g_type_add_interface_static(
+          type,
+          GetAtkInterfaceTypeFromWAIType(static_cast<WAIType>(i)),
+          &AtkInterfacesInitFunctions[i]);
+    }
+  }
+
+  return type;
+}
+
+BrowserAccessibilityAtk* browser_accessibility_new(
+    BrowserAccessibilityGtk* obj) {
+  GType type = GetAccessibilityTypeFromObject(obj);
+  AtkObject* atk_object = static_cast<AtkObject*>(g_object_new(type, 0));
+
+  atk_object_initialize(atk_object, obj);
+
+  return BROWSER_ACCESSIBILITY(atk_object);
+}
+
+void browser_accessibility_detach(BrowserAccessibilityAtk* atk_object) {
+}
+
+// static
+BrowserAccessibility* BrowserAccessibility::Create() {
+  return new BrowserAccessibilityGtk();
+}
+
+BrowserAccessibilityGtk* BrowserAccessibility::ToBrowserAccessibilityGtk() {
+  return static_cast<BrowserAccessibilityGtk*>(this);
+}
+
+BrowserAccessibilityGtk::BrowserAccessibilityGtk() {
+  atk_object_ = ATK_OBJECT(browser_accessibility_new(this));
+}
+
+BrowserAccessibilityGtk::~BrowserAccessibilityGtk() {
+  browser_accessibility_detach(BROWSER_ACCESSIBILITY(atk_object_));
+}
+
+AtkObject* BrowserAccessibilityGtk::GetAtkObject() const {
+  if (!G_IS_OBJECT(atk_object_))
+    return NULL;
+  return atk_object_;
+}
+
+void BrowserAccessibilityGtk::PreInitialize() {
+  BrowserAccessibility::PreInitialize();
+  InitRoleAndState();
+
+  if (this->parent()) {
+    atk_object_set_parent(
+        atk_object_,
+        this->parent()->ToBrowserAccessibilityGtk()->GetAtkObject());
+  }
+}
+
+bool BrowserAccessibilityGtk::IsNative() const {
+  return true;
+}
+
+void BrowserAccessibilityGtk::InitRoleAndState() {
+  atk_acc_name_ = UTF16ToUTF8(name()).c_str();
+
+  switch(role_) {
+    case WebAccessibility::ROLE_BUTTON:
+      atk_role_ = ATK_ROLE_PUSH_BUTTON;
+      break;
+    case WebAccessibility::ROLE_CHECKBOX:
+      atk_role_ = ATK_ROLE_CHECK_BOX;
+      break;
+    case WebAccessibility::ROLE_COMBO_BOX:
+      atk_role_ = ATK_ROLE_COMBO_BOX;
+      break;
+    case WebAccessibility::ROLE_LINK:
+      atk_role_ = ATK_ROLE_LINK;
+      break;
+    case WebAccessibility::ROLE_RADIO_BUTTON:
+      atk_role_ = ATK_ROLE_RADIO_BUTTON;
+      break;
+    case WebAccessibility::ROLE_TEXTAREA:
+      atk_role_ = ATK_ROLE_ENTRY;
+      break;
+    case WebAccessibility::ROLE_TEXT_FIELD:
+      atk_role_ = ATK_ROLE_ENTRY;
+      break;
+    case WebAccessibility::ROLE_WEBCORE_LINK:
+      atk_role_ = ATK_ROLE_LINK;
+      break;
+    default:
+      atk_role_ = ATK_ROLE_UNKNOWN;
+      break;
+  }
+}