chrome/renderer/resources/extensions/pepper_request.js

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 var SendResponse = requireNative('pepper_request_natives').SendResponse;
   6 var GetAvailability = requireNative('v8_context').GetAvailability;
   7 var utils = require('utils');
   8 var schemaRegistry = requireNative('schema_registry');
   9
  10 function takesCallback(targetName) {
  11   var parts = $String.split(targetName, '.');
  12   var schemaName = $Array.join($Array.slice(parts, 0, parts.length - 1), '.');
  13   var functionName = parts[parts.length - 1];
  14   var functions = schemaRegistry.GetSchema(schemaName).functions;
  15   var parameters = utils.lookup(functions, 'name', functionName).parameters;
  16   return parameters.length > 0 &&
  17          parameters[parameters.length - 1].type == 'function';
  18 }
  19
  20 function resolveName(name) {
  21   var availability = GetAvailability(name);
  22   if (!availability.is_available)
  23     throw Error(availability.message);
  24   var item = chrome;
  25   var nameComponents = $String.split(name, '.');
  26   for (var i = 0; i < nameComponents.length; i++) {
  27     item = item[nameComponents[i]];
  28   }
  29   return item;
  30 }
  31
  32 function startRequest(targetName, requestId) {
  33   var args = $Array.slice(arguments, 2);
  34   try {
  35     var hasCallback = takesCallback(targetName);
  36     if (hasCallback) {
  37       args.push(function() {
  38         var error = null;
  39         if (chrome.runtime.lastError)
  40           error = chrome.runtime.lastError.message;
  41         SendResponse(requestId, $Array.slice(arguments), error);
  42       });
  43     }
  44     var target = resolveName(targetName);
  45     var result = $Function.apply(target, null, args);
  46     if (!hasCallback)
  47       SendResponse(requestId, [result], null);
  48   } catch (e) {
  49     // TODO(sammc): Catch this from C++.
  50     return e.message;
  51   }
  52 }
  53
  54 exports.startRequest = startRequest;