CSE2410 Fall 2014 Bounce

// Copyright 2006-2008 the V8 project authors. All rights reserved.

// Redistribution and use in source and binary forms, with or without

// modification, are permitted provided that the following conditions are

// met:

//

//     * Redistributions of source code must retain the above copyright

//       notice, this list of conditions and the following disclaimer.

//     * Redistributions in binary form must reproduce the above

//       copyright notice, this list of conditions and the following

//       disclaimer in the documentation and/or other materials provided

//       with the distribution.

//     * Neither the name of Google Inc. nor the names of its

//       contributors may be used to endorse or promote products derived

//       from this software without specific prior written permission.

//

// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT

// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#include "v8.h"

#include "api.h"

#include "execution.h"

#include "spaces-inl.h"

#include "top.h"

namespace v8 { namespace internal {

// If no message listeners have been registered this one is called

// by default.

void MessageHandler::DefaultMessageReport(const MessageLocation* loc,

                                          Handle<Object> message_obj) {

  SmartPointer<char> str = GetLocalizedMessage(message_obj);

  if (loc == NULL) {

    PrintF("%s\n", *str);

  } else {

    HandleScope scope;

    Handle<Object> data(loc->script()->name());

    SmartPointer<char> data_str;

    if (data->IsString())

      data_str = Handle<String>::cast(data)->ToCString(DISALLOW_NULLS);

    PrintF("%s:%i: %s\n", *data_str ? *data_str : "<unknown>",

           loc->start_pos(), *str);

  }

}

void MessageHandler::ReportMessage(const char* msg) {

  PrintF("%s\n", msg);

}

Handle<Object> MessageHandler::MakeMessageObject(

    const char* type,

    MessageLocation* loc,

    Vector< Handle<Object> > args,

    Handle<String> stack_trace) {

  // Build error message object

  v8::HandleScope scope;  // Instantiate a closeable HandleScope for EscapeFrom.

  Handle<Object> type_str = Factory::LookupAsciiSymbol(type);

  Handle<Object> array = Factory::NewJSArray(args.length());

  for (int i = 0; i < args.length(); i++)

    SetElement(Handle<JSArray>::cast(array), i, args[i]);

  Handle<JSFunction> fun(Top::global_context()->make_message_fun());

  int start, end;

  Handle<Object> script;

  if (loc) {

    start = loc->start_pos();

    end = loc->end_pos();

    script = GetScriptWrapper(loc->script());

  } else {

    start = end = 0;

    script = Factory::undefined_value();

  }

  Handle<Object> start_handle(Smi::FromInt(start));

  Handle<Object> end_handle(Smi::FromInt(end));

  Handle<Object> stack_trace_val = stack_trace.is_null()

    ? Factory::undefined_value()

    : Handle<Object>::cast(stack_trace);

  const int argc = 6;

  Object** argv[argc] = { type_str.location(),

                          array.location(),

                          start_handle.location(),

                          end_handle.location(),

                          script.location(),

                          stack_trace_val.location() };

  // Setup a catch handler to catch exceptions in creating the message. This

  // handler is non-verbose to avoid calling MakeMessage recursively in case of

  // an exception.

  v8::TryCatch catcher;

  catcher.SetVerbose(false);

  catcher.SetCaptureMessage(false);

  // Format the message.

  bool caught_exception = false;

  Handle<Object> message =

      Execution::Call(fun, Factory::undefined_value(), argc, argv,

                      &caught_exception);

  // If creating the message (in JS code) resulted in an exception, we

  // skip doing the callback. This usually only happens in case of

  // stack overflow exceptions being thrown by the parser when the

  // stack is almost full.

  if (caught_exception) return Handle<Object>();

  return message.EscapeFrom(&scope);

}

void MessageHandler::ReportMessage(MessageLocation* loc,

                                   Handle<Object> message) {

  v8::Local<v8::Message> api_message_obj = v8::Utils::MessageToLocal(message);

  v8::NeanderArray global_listeners(Factory::message_listeners());

  int global_length = global_listeners.length();

  if (global_length == 0) {

    DefaultMessageReport(loc, message);

  } else {

    for (int i = 0; i < global_length; i++) {

      HandleScope scope;

      if (global_listeners.get(i)->IsUndefined()) continue;

      v8::NeanderObject listener(JSObject::cast(global_listeners.get(i)));

      Handle<Proxy> callback_obj(Proxy::cast(listener.get(0)));

      v8::MessageCallback callback =

          FUNCTION_CAST<v8::MessageCallback>(callback_obj->proxy());

      Handle<Object> callback_data(listener.get(1));

      callback(api_message_obj, v8::Utils::ToLocal(callback_data));

    }

  }

}

Handle<String> MessageHandler::GetMessage(Handle<Object> data) {

  Handle<String> fmt_str = Factory::LookupAsciiSymbol("FormatMessage");

  Handle<JSFunction> fun =

      Handle<JSFunction>(

          JSFunction::cast(

              Top::builtins()->GetProperty(*fmt_str)));

  Object** argv[1] = { data.location() };

  bool caught_exception;

  Handle<Object> result =

      Execution::TryCall(fun, Top::builtins(), 1, argv,

                         &caught_exception);

  if (caught_exception || !result->IsString()) {

    return Factory::LookupAsciiSymbol("<error>");

  }

  Handle<String> result_string = Handle<String>::cast(result);

  // A string that has been obtained from JS code in this way is

  // likely to be a complicated ConsString of some sort.  We flatten it

  // here to improve the efficiency of converting it to a C string and

  // other operations that are likely to take place (see GetLocalizedMessage

  // for example).

  FlattenString(result_string);

  return result_string;

}

SmartPointer<char> MessageHandler::GetLocalizedMessage(Handle<Object> data) {

  HandleScope scope;

  return GetMessage(data)->ToCString(DISALLOW_NULLS);

}

} }  // namespace v8::internal