Add button structs for PDF accessibility

This change adds struct PP_PrivateAccessibilityButtonFieldInfo to
PP_PrivateAccessibilityFormFieldInfo to transfer accessibility related
PDF button data (radio button, checkbox and push button) from the plugin
process to the mimehandler process. Made the same changes to the C++
versions of these structs and added the appropriate conversion code.

Bug: 1030242
Change-Id: I33eaab3c6471e017799c54ad8d9c98c43e1baeca
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2217716
Commit-Queue: Mansi Awasthi <maawas@microsoft.com>
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>
Reviewed-by: Ankit Kumar 🌪️ <ankk@microsoft.com>
Cr-Commit-Position: refs/heads/master@{#775964}

components/pdf/renderer/pdf_accessibility_tree.cc

@@ -410,6 +410,29 @@ bool PdfAccessibilityTree::IsDataFromPluginValid(
       return false;
   }
 
+  const std::vector<ppapi::PdfAccessibilityButtonInfo>& buttons =
+      page_objects.form_fields.buttons;
+  if (!std::is_sorted(
+          buttons.begin(), buttons.end(),
+          CompareTextRuns<ppapi::PdfAccessibilityButtonInfo>)) {
+    return false;
+  }
+  for (const ppapi::PdfAccessibilityButtonInfo& button :
+       buttons) {
+    // Text run index of an |button| works on the same logic as the text run
+    // index of a |link| as mentioned above.
+    if (button.text_run_index > text_runs.size())
+      return false;
+
+    // For radio button or checkbox, value of |button.control_index| should
+    // always be less than |button.control_count|.
+    if ((button.type == PP_PrivateButtonType::PP_PRIVATEBUTTON_CHECKBOX ||
+         button.type == PP_PrivateButtonType::PP_PRIVATEBUTTON_RADIOBUTTON) &&
+        (button.control_index >= button.control_count)) {
+      return false;
+    }
+  }
+
   return true;
 }
 

components/pdf/renderer/pdf_accessibility_tree_unittest.cc

@@ -300,4 +300,122 @@ TEST(PdfAccessibilityTreeUnitTest, OutOfBoundChoiceField) {
                                                            page_objects));
 }
 
+TEST(PdfAccessibilityTreeUnitTest, UnsortedButtonVector) {
+  std::vector<ppapi::PdfAccessibilityTextRunInfo> text_runs;
+  text_runs.emplace_back(kFirstTextRun);
+  text_runs.emplace_back(kSecondTextRun);
+
+  std::vector<PP_PrivateAccessibilityCharInfo> chars(
+      std::begin(kDummyCharsData), std::end(kDummyCharsData));
+
+  ppapi::PdfAccessibilityPageObjects page_objects;
+
+  {
+    // Add first button in the vector.
+    ppapi::PdfAccessibilityButtonInfo button;
+    button.text_run_index = 2;
+    page_objects.form_fields.buttons.push_back(std::move(button));
+  }
+
+  {
+    // Add second button in the vector.
+    ppapi::PdfAccessibilityButtonInfo button;
+    button.text_run_index = 0;
+    page_objects.form_fields.buttons.push_back(std::move(button));
+  }
+
+  EXPECT_FALSE(PdfAccessibilityTree::IsDataFromPluginValid(text_runs, chars,
+                                                           page_objects));
+}
+
+TEST(PdfAccessibilityTreeUnitTest, OutOfBoundButton) {
+  std::vector<ppapi::PdfAccessibilityTextRunInfo> text_runs;
+  text_runs.emplace_back(kFirstTextRun);
+  text_runs.emplace_back(kSecondTextRun);
+
+  std::vector<PP_PrivateAccessibilityCharInfo> chars(
+      std::begin(kDummyCharsData), std::end(kDummyCharsData));
+
+  ppapi::PdfAccessibilityPageObjects page_objects;
+
+  {
+    ppapi::PdfAccessibilityButtonInfo button;
+    button.text_run_index = 3;
+    page_objects.form_fields.buttons.push_back(std::move(button));
+  }
+
+  EXPECT_FALSE(PdfAccessibilityTree::IsDataFromPluginValid(text_runs, chars,
+                                                           page_objects));
+}
+
+TEST(PdfAccessibilityTreeUnitTest, OutOfBoundRadioButton) {
+  std::vector<ppapi::PdfAccessibilityTextRunInfo> text_runs;
+  text_runs.emplace_back(kFirstTextRun);
+  text_runs.emplace_back(kSecondTextRun);
+
+  std::vector<PP_PrivateAccessibilityCharInfo> chars(
+      std::begin(kDummyCharsData), std::end(kDummyCharsData));
+
+  ppapi::PdfAccessibilityPageObjects page_objects;
+
+  {
+    ppapi::PdfAccessibilityButtonInfo button;
+    button.type = PP_PrivateButtonType::PP_PRIVATEBUTTON_RADIOBUTTON;
+    button.text_run_index = 0;
+    button.control_index = 1;
+    button.control_count = 2;
+    page_objects.form_fields.buttons.push_back(std::move(button));
+  }
+
+  EXPECT_TRUE(PdfAccessibilityTree::IsDataFromPluginValid(text_runs, chars,
+                                                          page_objects));
+
+  {
+    ppapi::PdfAccessibilityButtonInfo button;
+    button.type = PP_PrivateButtonType::PP_PRIVATEBUTTON_RADIOBUTTON;
+    button.text_run_index = 0;
+    button.control_index = 3;
+    button.control_count = 2;
+    page_objects.form_fields.buttons.push_back(std::move(button));
+  }
+
+  EXPECT_FALSE(PdfAccessibilityTree::IsDataFromPluginValid(text_runs, chars,
+                                                           page_objects));
+}
+
+TEST(PdfAccessibilityTreeUnitTest, OutOfBoundCheckBox) {
+  std::vector<ppapi::PdfAccessibilityTextRunInfo> text_runs;
+  text_runs.emplace_back(kFirstTextRun);
+  text_runs.emplace_back(kSecondTextRun);
+
+  std::vector<PP_PrivateAccessibilityCharInfo> chars(
+      std::begin(kDummyCharsData), std::end(kDummyCharsData));
+
+  ppapi::PdfAccessibilityPageObjects page_objects;
+
+  {
+    ppapi::PdfAccessibilityButtonInfo button;
+    button.type = PP_PrivateButtonType::PP_PRIVATEBUTTON_CHECKBOX;
+    button.text_run_index = 0;
+    button.control_index = 1;
+    button.control_count = 2;
+    page_objects.form_fields.buttons.push_back(std::move(button));
+  }
+
+  EXPECT_TRUE(PdfAccessibilityTree::IsDataFromPluginValid(text_runs, chars,
+                                                          page_objects));
+
+  {
+    ppapi::PdfAccessibilityButtonInfo button;
+    button.type = PP_PrivateButtonType::PP_PRIVATEBUTTON_CHECKBOX;
+    button.text_run_index = 0;
+    button.control_index = 3;
+    button.control_count = 2;
+    page_objects.form_fields.buttons.push_back(std::move(button));
+  }
+
+  EXPECT_FALSE(PdfAccessibilityTree::IsDataFromPluginValid(text_runs, chars,
+                                                           page_objects));
+}
+
 }  // namespace pdf

pdf/pdfium/pdfium_assert_matching_enums.cc

@@ -240,6 +240,10 @@ STATIC_ASSERT_ENUM(chrome_pdf::PDFEngine::FormType::kXFAForeground,
                    FORMTYPE_XFA_FOREGROUND);
 STATIC_ASSERT_ENUM(chrome_pdf::PDFEngine::FormType::kCount, FORMTYPE_COUNT);
 
+STATIC_ASSERT_ENUM(PP_PRIVATEBUTTON_PUSHBUTTON, FPDF_FORMFIELD_PUSHBUTTON);
+STATIC_ASSERT_ENUM(PP_PRIVATEBUTTON_CHECKBOX, FPDF_FORMFIELD_CHECKBOX);
+STATIC_ASSERT_ENUM(PP_PRIVATEBUTTON_RADIOBUTTON, FPDF_FORMFIELD_RADIOBUTTON);
+
 #if defined(OS_WIN)
 STATIC_ASSERT_ENUM(chrome_pdf::kEmf, FPDF_PRINTMODE_EMF);
 STATIC_ASSERT_ENUM(chrome_pdf::kTextOnly, FPDF_PRINTMODE_TEXTONLY);

ppapi/c/private/ppb_pdf.h

@@ -124,6 +124,9 @@ struct PP_PrivateAccessibilityLinkInfo {
   uint32_t url_length;
   // Index of the link in the page. This will be used to identify the link on
   // which action has to be performed in the page.
+  // |index_in_page| is populated and used in plugin process to handle
+  // accessiility actions from mimehandler process. It's value should be
+  // validated in plugin before usage.
   uint32_t index_in_page;
   // Link can either be part of the page text or not. If the link is part of the
   // page text, then |text_run_index| denotes the text run which contains the
@@ -167,6 +170,9 @@ struct PP_PrivateAccessibilityHighlightInfo {
   uint32_t note_text_length;
   // Index of the highlight in the page annotation list. Used to identify the
   // annotation on which action needs to be performed.
+  // |index_in_page| is populated and used in plugin process to handle
+  // accessiility actions from mimehandler process. It's value should be
+  // validated in plugin before usage.
   uint32_t index_in_page;
   // Highlights are annotations over existing page text.  |text_run_index|
   // denotes the index of the text run where the highlight starts and
@@ -202,6 +208,9 @@ struct PP_PrivateAccessibilityTextFieldInfo {
   bool is_password;
   // Index of the text field in the collection of text fields in the page. Used
   // to identify the annotation on which action needs to be performed.
+  // |index_in_page| is populated and used in plugin process to handle
+  // accessiility actions from mimehandler process. It's value should be
+  // validated in plugin before usage.
   uint32_t index_in_page;
   // We anchor the text field to a text run index, this denotes the text run
   // before which the text field should be inserted in the accessibility tree.
@@ -252,6 +261,9 @@ struct PP_PrivateAccessibilityChoiceFieldInfo {
   bool has_editable_text_box;
   // Index of the choice field in the collection of choice fields in the page.
   // Used to identify the annotation on which action needs to be performed.
+  // |index_in_page| is populated and used in plugin process to handle
+  // accessiility actions from mimehandler process. It's value should be
+  // validated in plugin before usage.
   uint32_t index_in_page;
   // We anchor the choice field to a text run index, this denotes the text run
   // before which the choice field should be inserted in the accessibility tree.
@@ -260,6 +272,56 @@ struct PP_PrivateAccessibilityChoiceFieldInfo {
   struct PP_FloatRect bounds;
 };
 
+typedef enum {
+  PP_PRIVATEBUTTON_PUSHBUTTON = 1,
+  PP_PRIVATEBUTTON_FIRST = PP_PRIVATEBUTTON_PUSHBUTTON,
+  PP_PRIVATEBUTTON_CHECKBOX = 2,
+  PP_PRIVATEBUTTON_RADIOBUTTON = 3,
+  PP_PRIVATEBUTTON_LAST = PP_PRIVATEBUTTON_RADIOBUTTON
+} PP_PrivateButtonType;
+
+// This holds button form field information provided by the PDF and will be
+// used in accessibility to expose it. Needs to stay in sync with C++ versions
+// (PdfAccessibilityButtonInfo and PrivateAccessibilityButtonInfo).
+// This struct contains index states that should be validated using
+// PdfAccessibilityTree::IsDataFromPluginValid() before usage.
+struct PP_PrivateAccessibilityButtonInfo {
+  // Represents the name property of button, if present.
+  const char* name;
+  uint32_t name_length;
+  // Represents the value property of button, if present.
+  const char* value;
+  uint32_t value_length;
+  // Represents the button type.
+  PP_PrivateButtonType type;
+  // Represents if the button is non-editable.
+  bool is_read_only;
+  // Represents if the radio button or check box is checked or not.
+  bool is_checked;
+  // Represents count of controls in the control group. A group of interactive
+  // form annotations is collectively called a form control group. Here, an
+  // interactive form annotation, should be either a radio button or a checkbox.
+  // Value of |control_count| is >= 1.
+  uint32_t control_count;
+  // Represents index of the control in the control group. A group of
+  // interactive form annotations is collectively called a form control group.
+  // Here, an interactive form annotation, should be either a radio button or a
+  // checkbox. Value of |control_index| should always be less than
+  // |control_count|.
+  uint32_t control_index;
+  // Index of the button in the collection of buttons in the page. Used
+  // to identify the annotation on which action needs to be performed.
+  // |index_in_page| is populated and used in plugin process to handle
+  // accessiility actions from mimehandler process. It's value should be
+  // validated in plugin before usage.
+  uint32_t index_in_page;
+  // We anchor the button to a text run index, this denotes the text run
+  // before which the button should be inserted in the accessibility tree.
+  uint32_t text_run_index;
+  // Bounding box of the button.
+  struct PP_FloatRect bounds;
+};
+
 // This holds form fields within a PDF page. Needs to stay in sync with C++
 // versions (PdfAccessibilityFormFieldInfo and
 // PrivateAccessibilityFormFieldInfo).
@@ -268,6 +330,8 @@ struct PP_PrivateAccessibilityFormFieldInfo {
   uint32_t text_field_count;
   struct PP_PrivateAccessibilityChoiceFieldInfo* choice_fields;
   uint32_t choice_field_count;
+  struct PP_PrivateAccessibilityButtonInfo* buttons;
+  uint32_t button_count;
 };
 
 // This holds different PDF page objects - links, images, highlights and

ppapi/cpp/private/pdf.cc

@@ -113,6 +113,23 @@ void ConvertPrivateAccessibilityChoiceFieldInfo(
   info->bounds = choice_field.bounds;
 }
 
+void ConvertPrivateAccessibilityButtonInfo(
+    const PDF::PrivateAccessibilityButtonInfo& button,
+    PP_PrivateAccessibilityButtonInfo* info) {
+  info->name = button.name.c_str();
+  info->name_length = button.name.size();
+  info->value = button.value.c_str();
+  info->value_length = button.value.size();
+  info->type = button.type;
+  info->is_read_only = button.is_read_only;
+  info->is_checked = button.is_checked;
+  info->control_count = button.control_count;
+  info->control_index = button.control_index;
+  info->index_in_page = button.index_in_page;
+  info->text_run_index = button.text_run_index;
+  info->bounds = button.bounds;
+}
+
 }  // namespace
 
 // static
@@ -344,6 +361,12 @@ void PDF::SetAccessibilityPageInfo(
                                                  &choice_field_option_info[i]);
     }
 
+    const std::vector<PrivateAccessibilityButtonInfo>& buttons =
+        page_objects.form_fields.buttons;
+    std::vector<PP_PrivateAccessibilityButtonInfo> button_info(buttons.size());
+    for (size_t i = 0; i < buttons.size(); ++i)
+      ConvertPrivateAccessibilityButtonInfo(buttons[i], &button_info[i]);
+
     PP_PrivateAccessibilityPageObjects pp_page_objects;
     pp_page_objects.links = link_info.data();
     pp_page_objects.link_count = link_info.size();
@@ -355,6 +378,8 @@ void PDF::SetAccessibilityPageInfo(
     pp_page_objects.form_fields.text_field_count = text_field_info.size();
     pp_page_objects.form_fields.choice_fields = choice_field_info.data();
     pp_page_objects.form_fields.choice_field_count = choice_field_info.size();
+    pp_page_objects.form_fields.buttons = button_info.data();
+    pp_page_objects.form_fields.button_count = button_info.size();
 
     get_interface<PPB_PDF>()->SetAccessibilityPageInfo(
         instance.pp_instance(), page_info, text_run_info.data(), chars.data(),

ppapi/cpp/private/pdf.h

@@ -128,11 +128,42 @@ class PDF {
     FloatRect bounds;
   };
 
+  // C++ version of PP_PrivateAccessibilityButtonInfo.
+  // Needs to stay in sync with the C version.
+  struct PrivateAccessibilityButtonInfo {
+    std::string name;
+    std::string value;
+    // Represents the button type.
+    PP_PrivateButtonType type;
+    // Represents if the button is non-editable.
+    bool is_read_only;
+    // Represents if the radio button or check box is checked or not.
+    bool is_checked;
+    // Represents count of controls in the control group. A group of interactive
+    // form annotations is collectively called a form control group. Here, an
+    // interactive form annotation, should be either a radio button or a
+    // checkbox. Value of |control_count| is >= 1.
+    uint32_t control_count;
+    // Represents index of the control in the control group. A group of
+    // interactive form annotations is collectively called a form control group.
+    // Here, an interactive form annotation, should be either a radio button or
+    // a checkbox. Value of |control_index| should always be less than
+    // |control_count|.
+    uint32_t control_index;
+    // Index of this button in the collection of buttons in the page.
+    uint32_t index_in_page;
+    // We anchor the button to a text run index, this denotes the text run
+    // before which the button should be inserted in the accessibility tree.
+    uint32_t text_run_index;
+    FloatRect bounds;
+  };
+
   // C++ version of PP_PrivateAccessibilityFormFieldInfo.
   // Needs to stay in sync with the C version.
   struct PrivateAccessibilityFormFieldInfo {
     std::vector<PrivateAccessibilityTextFieldInfo> text_fields;
     std::vector<PrivateAccessibilityChoiceFieldInfo> choice_fields;
+    std::vector<PrivateAccessibilityButtonInfo> buttons;
   };
 
   // C++ version of PP_PrivateAccessibilityPageObjects.

ppapi/proxy/ppapi_messages.h

@@ -160,6 +160,9 @@ IPC_ENUM_TRAITS_MAX_VALUE(PP_PdfAccessibilityScrollAlignment,
 IPC_ENUM_TRAITS_MAX_VALUE(PP_PdfAccessibilityAnnotationType,
                           PP_PDF_ACCESSIBILITY_ANNOTATIONTYPE_LAST)
 IPC_ENUM_TRAITS_MAX_VALUE(PP_PrivateChoiceFieldType, PP_PRIVATECHOICEFIELD_LAST)
+IPC_ENUM_TRAITS_MIN_MAX_VALUE(PP_PrivateButtonType,
+                              PP_PRIVATEBUTTON_FIRST,
+                              PP_PRIVATEBUTTON_LAST)
 
 IPC_STRUCT_TRAITS_BEGIN(PP_Point)
   IPC_STRUCT_TRAITS_MEMBER(x)
@@ -365,9 +368,23 @@ IPC_STRUCT_TRAITS_BEGIN(ppapi::PdfAccessibilityChoiceFieldInfo)
   IPC_STRUCT_TRAITS_MEMBER(bounds)
 IPC_STRUCT_TRAITS_END()
 
+IPC_STRUCT_TRAITS_BEGIN(ppapi::PdfAccessibilityButtonInfo)
+  IPC_STRUCT_TRAITS_MEMBER(name)
+  IPC_STRUCT_TRAITS_MEMBER(value)
+  IPC_STRUCT_TRAITS_MEMBER(type)
+  IPC_STRUCT_TRAITS_MEMBER(is_read_only)
+  IPC_STRUCT_TRAITS_MEMBER(is_checked)
+  IPC_STRUCT_TRAITS_MEMBER(control_count)
+  IPC_STRUCT_TRAITS_MEMBER(control_index)
+  IPC_STRUCT_TRAITS_MEMBER(index_in_page)
+  IPC_STRUCT_TRAITS_MEMBER(text_run_index)
+  IPC_STRUCT_TRAITS_MEMBER(bounds)
+IPC_STRUCT_TRAITS_END()
+
 IPC_STRUCT_TRAITS_BEGIN(ppapi::PdfAccessibilityFormFieldInfo)
   IPC_STRUCT_TRAITS_MEMBER(text_fields)
   IPC_STRUCT_TRAITS_MEMBER(choice_fields)
+  IPC_STRUCT_TRAITS_MEMBER(buttons)
 IPC_STRUCT_TRAITS_END()
 
 IPC_STRUCT_TRAITS_BEGIN(ppapi::PdfAccessibilityPageObjects)

ppapi/shared_impl/pdf_accessibility_shared.cc

@@ -120,6 +120,23 @@ PdfAccessibilityChoiceFieldInfo::PdfAccessibilityChoiceFieldInfo(
   }
 }
 
+PdfAccessibilityButtonInfo::PdfAccessibilityButtonInfo() = default;
+
+PdfAccessibilityButtonInfo::~PdfAccessibilityButtonInfo() = default;
+
+PdfAccessibilityButtonInfo::PdfAccessibilityButtonInfo(
+    const PP_PrivateAccessibilityButtonInfo& button)
+    : name(std::string(button.name, button.name_length)),
+      value(std::string(button.value, button.value_length)),
+      type(button.type),
+      is_read_only(button.is_read_only),
+      is_checked(button.is_checked),
+      control_count(button.control_count),
+      control_index(button.control_index),
+      index_in_page(button.index_in_page),
+      text_run_index(button.text_run_index),
+      bounds(button.bounds) {}
+
 PdfAccessibilityFormFieldInfo::PdfAccessibilityFormFieldInfo() = default;
 
 PdfAccessibilityFormFieldInfo::PdfAccessibilityFormFieldInfo(
@@ -133,6 +150,11 @@ PdfAccessibilityFormFieldInfo::PdfAccessibilityFormFieldInfo(
   for (size_t i = 0; i < form_fields.choice_field_count; i++) {
     choice_fields.emplace_back(form_fields.choice_fields[i]);
   }
+
+  buttons.reserve(form_fields.button_count);
+  for (size_t i = 0; i < form_fields.button_count; i++) {
+    buttons.emplace_back(form_fields.buttons[i]);
+  }
 }
 
 PdfAccessibilityFormFieldInfo::~PdfAccessibilityFormFieldInfo() = default;

ppapi/shared_impl/pdf_accessibility_shared.h

@@ -137,6 +137,25 @@ struct PPAPI_SHARED_EXPORT PdfAccessibilityChoiceFieldInfo {
   PP_FloatRect bounds;
 };
 
+// Needs to stay in sync with PP_PrivateAccessibilityButtonInfo.
+struct PPAPI_SHARED_EXPORT PdfAccessibilityButtonInfo {
+  PdfAccessibilityButtonInfo();
+  explicit PdfAccessibilityButtonInfo(
+      const PP_PrivateAccessibilityButtonInfo& button);
+  ~PdfAccessibilityButtonInfo();
+
+  std::string name;
+  std::string value;
+  PP_PrivateButtonType type;
+  bool is_read_only;
+  bool is_checked;
+  uint32_t control_count;
+  uint32_t control_index;
+  uint32_t index_in_page;
+  uint32_t text_run_index;
+  PP_FloatRect bounds;
+};
+
 // Needs to stay in sync with PP_PrivateAccessibilityFormFieldInfo.
 struct PPAPI_SHARED_EXPORT PdfAccessibilityFormFieldInfo {
   PdfAccessibilityFormFieldInfo();
@@ -146,6 +165,7 @@ struct PPAPI_SHARED_EXPORT PdfAccessibilityFormFieldInfo {
 
   std::vector<PdfAccessibilityTextFieldInfo> text_fields;
   std::vector<PdfAccessibilityChoiceFieldInfo> choice_fields;
+  std::vector<PdfAccessibilityButtonInfo> buttons;
 };
 
 // Needs to stay in sync with PP_PrivateAccessibilityPageObjects.