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.

// This file contains infrastructure used by the API.  See

// v8natives.js for an explanation of these files are processed and

// loaded.

function CreateDate(time) {

  var date = new $Date();

  date.setTime(time);

  return date;

}

var kApiFunctionCache = new InternalArray();

var functionCache = kApiFunctionCache;

function Instantiate(data, name) {

  if (!%IsTemplate(data)) return data;

  var tag = %GetTemplateField(data, kApiTagOffset);

  switch (tag) {

    case kFunctionTag:

      return InstantiateFunction(data, name);

    case kNewObjectTag:

      var Constructor = %GetTemplateField(data, kApiConstructorOffset);

      // Note: Do not directly use a function template as a condition, our

      // internal ToBoolean doesn't handle that!

      var result = typeof Constructor === 'undefined' ?

          {} : new (Instantiate(Constructor))();

      ConfigureTemplateInstance(result, data);

      result = %ToFastProperties(result);

      return result;

    default:

      throw 'Unknown API tag <' + tag + '>';

  }

}

function InstantiateFunction(data, name) {

  // We need a reference to kApiFunctionCache in the stack frame

  // if we need to bail out from a stack overflow.

  var cache = kApiFunctionCache;

  var serialNumber = %GetTemplateField(data, kApiSerialNumberOffset);

  var isFunctionCached =

   (serialNumber in cache) && (cache[serialNumber] != kUninitialized);

  if (!isFunctionCached) {

    try {

      var fun = %CreateApiFunction(data);

      if (name) %FunctionSetName(fun, name);

      var flags = %GetTemplateField(data, kApiFlagOffset);

      var doNotCache = flags & (1 << kDoNotCacheBit);

      if (!doNotCache) cache[serialNumber] = fun;

      if (flags & (1 << kRemovePrototypeBit)) {

        %FunctionRemovePrototype(fun);

      } else {

        var prototype = %GetTemplateField(data, kApiPrototypeTemplateOffset);

        // Note: Do not directly use an object template as a condition, our

        // internal ToBoolean doesn't handle that!

        fun.prototype = typeof prototype === 'undefined' ?

            {} : Instantiate(prototype);

        if (flags & (1 << kReadOnlyPrototypeBit)) {

          %FunctionSetReadOnlyPrototype(fun);

        }

        %SetProperty(fun.prototype, "constructor", fun, DONT_ENUM);

        var parent = %GetTemplateField(data, kApiParentTemplateOffset);

        // Note: Do not directly use a function template as a condition, our

        // internal ToBoolean doesn't handle that!

        if (!(typeof parent === 'undefined')) {

          var parent_fun = Instantiate(parent);

          %SetPrototype(fun.prototype, parent_fun.prototype);

        }

      }

      ConfigureTemplateInstance(fun, data);

      if (doNotCache) return fun;

    } catch (e) {

      cache[serialNumber] = kUninitialized;

      throw e;

    }

  }

  return cache[serialNumber];

}

function ConfigureTemplateInstance(obj, data) {

  var properties = %GetTemplateField(data, kApiPropertyListOffset);

  if (!properties) return;

  // Disable access checks while instantiating the object.

  var requires_access_checks = %DisableAccessChecks(obj);

  try {

    for (var i = 1; i < properties[0];) {

      var length = properties[i];

      if (length == 3) {

        var name = properties[i + 1];

        var prop_data = properties[i + 2];

        var attributes = properties[i + 3];

        var value = Instantiate(prop_data, name);

        %SetProperty(obj, name, value, attributes);

      } else if (length == 5) {

        var name = properties[i + 1];

        var getter = properties[i + 2];

        var setter = properties[i + 3];

        var attribute = properties[i + 4];

        var access_control = properties[i + 5];

        %SetAccessorProperty(

            obj, name, getter, setter, attribute, access_control);

      } else {

        throw "Bad properties array";

      }

      i += length + 1;

    }

  } finally {

    if (requires_access_checks) %EnableAccessChecks(obj);

  }

}