[Extensions Bindings] Add a bindings/ subdirectory under renderer

extensions/renderer/api_last_error.cc

-// Copyright 2017 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 "extensions/renderer/api_last_error.h"
-
-#include "gin/converter.h"
-#include "gin/handle.h"
-#include "gin/object_template_builder.h"
-#include "gin/wrappable.h"
-
-namespace extensions {
-
-namespace {
-
-const char kLastErrorProperty[] = "lastError";
-const char kScriptSuppliedValueKey[] = "script_supplied_value";
-
-// The object corresponding to the lastError property, containing a single
-// property ('message') with the last error. This object is stored on the parent
-// (chrome.runtime in production) as a private property, and is returned via an
-// accessor which marks the error as accessed.
-class LastErrorObject final : public gin::Wrappable<LastErrorObject> {
- public:
-  explicit LastErrorObject(const std::string& error) : error_(error) {}
-
-  static gin::WrapperInfo kWrapperInfo;
-
-  // gin::Wrappable:
-  gin::ObjectTemplateBuilder GetObjectTemplateBuilder(
-      v8::Isolate* isolate) override {
-    DCHECK(isolate);
-    return Wrappable<LastErrorObject>::GetObjectTemplateBuilder(isolate)
-        .SetProperty("message", &LastErrorObject::error);
-  }
-
-  void Reset(const std::string& error) {
-    error_ = error;
-    accessed_ = false;
-  }
-
-  const std::string& error() const { return error_; }
-  bool accessed() const { return accessed_; }
-  void set_accessed() { accessed_ = true; }
-
- private:
-  std::string error_;
-  bool accessed_ = false;
-
-  DISALLOW_COPY_AND_ASSIGN(LastErrorObject);
-};
-
-gin::WrapperInfo LastErrorObject::kWrapperInfo = {gin::kEmbedderNativeGin};
-
-// An accessor to retrieve the last error property (curried in through data),
-// and mark it as accessed.
-void LastErrorGetter(v8::Local<v8::Name> property,
-                     const v8::PropertyCallbackInfo<v8::Value>& info) {
-  v8::Isolate* isolate = info.GetIsolate();
-  v8::HandleScope handle_scope(isolate);
-  v8::Local<v8::Object> holder = info.Holder();
-  v8::Local<v8::Context> context = holder->CreationContext();
-
-  v8::Local<v8::Value> last_error;
-  v8::Local<v8::Private> last_error_key = v8::Private::ForApi(
-      isolate, gin::StringToSymbol(isolate, kLastErrorProperty));
-  if (!holder->GetPrivate(context, last_error_key).ToLocal(&last_error) ||
-      last_error != info.Data()) {
-    // Something funny happened - our private properties aren't set right.
-    NOTREACHED();
-    return;
-  }
-
-  v8::Local<v8::Value> return_value;
-
-  // It's possible that some script has set their own value for the last error
-  // property. If so, return that. Otherwise, return the real last error.
-  v8::Local<v8::Private> script_value_key = v8::Private::ForApi(
-      isolate, gin::StringToSymbol(isolate, kScriptSuppliedValueKey));
-  v8::Local<v8::Value> script_value;
-  if (holder->GetPrivate(context, script_value_key).ToLocal(&script_value) &&
-      !script_value->IsUndefined()) {
-    return_value = script_value;
-  } else {
-    LastErrorObject* last_error_obj = nullptr;
-    CHECK(gin::Converter<LastErrorObject*>::FromV8(isolate, last_error,
-                                                   &last_error_obj));
-    last_error_obj->set_accessed();
-    return_value = last_error;
-  }
-
-  info.GetReturnValue().Set(return_value);
-}
-
-// Allow script to set the last error property.
-void LastErrorSetter(v8::Local<v8::Name> property,
-                     v8::Local<v8::Value> value,
-                     const v8::PropertyCallbackInfo<void>& info) {
-  v8::Isolate* isolate = info.GetIsolate();
-  v8::HandleScope handle_scope(isolate);
-  v8::Local<v8::Object> holder = info.Holder();
-  v8::Local<v8::Context> context = holder->CreationContext();
-
-  v8::Local<v8::Private> script_value_key = v8::Private::ForApi(
-      isolate, gin::StringToSymbol(isolate, kScriptSuppliedValueKey));
-  v8::Maybe<bool> set_private =
-      holder->SetPrivate(context, script_value_key, value);
-  if (!set_private.IsJust() || !set_private.FromJust())
-    NOTREACHED();
-}
-
-}  // namespace
-
-APILastError::APILastError(const GetParent& get_parent,
-                           const AddConsoleError& add_console_error)
-    : get_parent_(get_parent), add_console_error_(add_console_error) {}
-APILastError::APILastError(APILastError&& other) = default;
-APILastError::~APILastError() = default;
-
-void APILastError::SetError(v8::Local<v8::Context> context,
-                            const std::string& error) {
-  v8::Isolate* isolate = context->GetIsolate();
-  DCHECK(isolate);
-  v8::HandleScope handle_scope(isolate);
-
-  // The various accesses/sets on an object could potentially fail if script has
-  // set any crazy interceptors. For the most part, we don't care about behaving
-  // perfectly in these circumstances, but we eat the exception so callers don't
-  // have to worry about it. We also SetVerbose() so that developers will have a
-  // clue what happened if this does arise.
-  // TODO(devlin): Whether or not this needs to be verbose is debatable.
-  v8::TryCatch try_catch(isolate);
-  try_catch.SetVerbose(true);
-
-  v8::Local<v8::Object> parent = get_parent_.Run(context);
-  if (parent.IsEmpty())
-    return;
-  v8::Local<v8::String> key = gin::StringToSymbol(isolate, kLastErrorProperty);
-  v8::Local<v8::Value> v8_error;
-  // Two notes: this Get() is visible to external script, and this will actually
-  // mark the lastError as accessed, if one exists. These shouldn't be a
-  // problem (lastError is meant to be helpful, but isn't designed to handle
-  // crazy chaining, etc). However, if we decide we needed to be fancier, we
-  // could detect the presence of a current error through a GetPrivate(), and
-  // optionally throw it if one exists.
-  if (!parent->Get(context, key).ToLocal(&v8_error))
-    return;
-
-  if (!v8_error->IsUndefined()) {
-    // There may be an existing last error to overwrite.
-    LastErrorObject* last_error = nullptr;
-    if (!gin::Converter<LastErrorObject*>::FromV8(isolate, v8_error,
-                                                  &last_error)) {
-      // If it's not a real lastError (e.g. if a script manually set it), don't
-      // do anything. We shouldn't mangle a property set by other script.
-      // TODO(devlin): Or should we? If someone sets chrome.runtime.lastError,
-      // it might be the right course of action to overwrite it.
-      return;
-    }
-    last_error->Reset(error);
-  } else {
-    v8::Local<v8::Value> last_error =
-        gin::CreateHandle(isolate, new LastErrorObject(error)).ToV8();
-    v8::Maybe<bool> set_private = parent->SetPrivate(
-        context, v8::Private::ForApi(isolate, key), last_error);
-    if (!set_private.IsJust() || !set_private.FromJust()) {
-      NOTREACHED();
-      return;
-    }
-    DCHECK(!last_error.IsEmpty());
-    // This Set() can fail, but there's nothing to do if it does (the exception
-    // will be caught by the TryCatch above).
-    ignore_result(parent->SetAccessor(context, key, &LastErrorGetter,
-                                      &LastErrorSetter, last_error));
-  }
-}
-
-void APILastError::ClearError(v8::Local<v8::Context> context,
-                              bool report_if_unchecked) {
-  v8::Isolate* isolate = context->GetIsolate();
-  v8::HandleScope handle_scope(isolate);
-
-  v8::Local<v8::Object> parent;
-  LastErrorObject* last_error = nullptr;
-  v8::Local<v8::String> key;
-  v8::Local<v8::Private> private_key;
-  {
-    // See comment in SetError().
-    v8::TryCatch try_catch(isolate);
-    try_catch.SetVerbose(true);
-
-    parent = get_parent_.Run(context);
-    if (parent.IsEmpty())
-      return;
-    key = gin::StringToSymbol(isolate, kLastErrorProperty);
-    private_key = v8::Private::ForApi(isolate, key);
-    v8::Local<v8::Value> error;
-    // Access through GetPrivate() so that we don't trigger accessed().
-    if (!parent->GetPrivate(context, private_key).ToLocal(&error))
-      return;
-    if (!gin::Converter<LastErrorObject*>::FromV8(context->GetIsolate(), error,
-                                                  &last_error)) {
-      return;
-    }
-  }
-
-  if (report_if_unchecked && !last_error->accessed()) {
-    add_console_error_.Run(
-        context, "Unchecked runtime.lastError: " + last_error->error());
-  }
-
-  // See comment in SetError().
-  v8::TryCatch try_catch(isolate);
-  try_catch.SetVerbose(true);
-
-  v8::Maybe<bool> delete_private = parent->DeletePrivate(context, private_key);
-  if (!delete_private.IsJust() || !delete_private.FromJust()) {
-    NOTREACHED();
-    return;
-  }
-  // This Delete() can fail, but there's nothing to do if it does (the exception
-  // will be caught by the TryCatch above).
-  ignore_result(parent->Delete(context, key));
-}
-
-bool APILastError::HasError(v8::Local<v8::Context> context) {
-  v8::Isolate* isolate = context->GetIsolate();
-  v8::HandleScope handle_scope(isolate);
-
-  // See comment in SetError().
-  v8::TryCatch try_catch(isolate);
-  try_catch.SetVerbose(true);
-
-  v8::Local<v8::Object> parent = get_parent_.Run(context);
-  if (parent.IsEmpty())
-    return false;
-  v8::Local<v8::Value> error;
-  v8::Local<v8::Private> key = v8::Private::ForApi(
-      isolate, gin::StringToSymbol(isolate, kLastErrorProperty));
-  // Access through GetPrivate() so we don't trigger accessed().
-  if (!parent->GetPrivate(context, key).ToLocal(&error))
-    return false;
-
-  LastErrorObject* last_error = nullptr;
-  return gin::Converter<LastErrorObject*>::FromV8(context->GetIsolate(), error,
-                                                  &last_error);
-}
-
-}  // namespace extensions