native_client_sdk/src/examples/api/file_io/example.js

   1 // Copyright (c) 2012 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 function moduleDidLoad() {
   6   common.hideModule();
   7 }
   8
   9 // Called by the common.js module.
  10 function domContentLoaded(name, tc, config, width, height) {
  11   navigator.webkitPersistentStorage.requestQuota(5 * 1024 * 1024,
  12     function(bytes) {
  13       common.updateStatus(
  14           'Allocated ' + bytes + ' bytes of persistant storage.');
  15       common.attachDefaultListeners();
  16       common.createNaClModule(name, tc, config, width, height);
  17     },
  18     function(e) { alert('Failed to allocate space') });
  19 }
  20
  21 // Called by the common.js module.
  22 function attachListeners() {
  23   var radioEls = document.querySelectorAll('input[type="radio"]');
  24   for (var i = 0; i < radioEls.length; ++i) {
  25     radioEls[i].addEventListener('click', onRadioClicked);
  26   }
  27
  28   function addEventListenerToButton(parentId, func) {
  29     document.querySelector('#' + parentId + ' button')
  30         .addEventListener('click', func);
  31   }
  32
  33   addEventListenerToButton('saveFile', saveFile);
  34   addEventListenerToButton('loadFile', loadFile);
  35   addEventListenerToButton('delete', deleteFileOrDirectory);
  36   addEventListenerToButton('listDir', listDir);
  37   addEventListenerToButton('makeDir', makeDir);
  38   addEventListenerToButton('rename', rename);
  39 }
  40
  41 function onRadioClicked(e) {
  42   var divId = this.id.slice(6);  // skip "radio_"
  43   var functionEls = document.querySelectorAll('.function');
  44   for (var i = 0; i < functionEls.length; ++i) {
  45     var visible = functionEls[i].id === divId;
  46     if (functionEls[i].id === divId)
  47       functionEls[i].removeAttribute('hidden');
  48     else
  49       functionEls[i].setAttribute('hidden', '');
  50   }
  51 }
  52
  53 function makeMessage(command, path) {
  54   // Package a message using a simple protocol containing:
  55   // [command, <path>, <extra args>...]
  56   var msg = [command, path];
  57   for (var i = 2; i < arguments.length; ++i) {
  58     msg.push(arguments[i]);
  59   }
  60   return msg;
  61 }
  62
  63 function saveFile() {
  64   if (common.naclModule) {
  65     var fileName = document.querySelector('#saveFile input').value;
  66     var fileText = document.querySelector('#saveFile textarea').value;
  67     common.naclModule.postMessage(makeMessage('save', fileName, fileText));
  68     // clear the editor.
  69     fileText.value = '';
  70   }
  71 }
  72
  73 function loadFile() {
  74   if (common.naclModule) {
  75     var fileName = document.querySelector('#loadFile input').value;
  76     // clear the editor first (in case there is an error and there is no
  77     // output).
  78     document.querySelector('#loadFile textarea').value = '';
  79     common.naclModule.postMessage(makeMessage('load', fileName));
  80   }
  81 }
  82
  83 function deleteFileOrDirectory() {
  84   if (common.naclModule) {
  85     var fileName = document.querySelector('#delete input').value;
  86     common.naclModule.postMessage(makeMessage('delete', fileName));
  87   }
  88 }
  89
  90 function listDir() {
  91   if (common.naclModule) {
  92     var dirName = document.querySelector('#listDir input').value;
  93     common.naclModule.postMessage(makeMessage('list', dirName));
  94   }
  95 }
  96
  97 function makeDir() {
  98   if (common.naclModule) {
  99     var dirName = document.querySelector('#makeDir input').value;
 100     common.naclModule.postMessage(makeMessage('makedir', dirName));
 101   }
 102 }
 103
 104 function rename() {
 105   if (common.naclModule) {
 106     var oldName = document.querySelector('#renameOld').value;
 107     var newName = document.querySelector('#renameNew').value;
 108     common.naclModule.postMessage(makeMessage('rename', oldName, newName));
 109   }
 110 }
 111
 112 // Called by the common.js module.
 113 function handleMessage(message_event) {
 114   var msg = message_event.data;
 115   var command = msg[0];
 116   var args = msg.slice(1);
 117
 118   if (command == 'ERR') {
 119     common.logMessage('Error: ' + args[0]);
 120   } else if (command == 'STAT') {
 121     common.logMessage(args[0]);
 122   } else if (command == 'READY') {
 123     common.logMessage('Filesystem ready!');
 124   } else if (command == 'DISP') {
 125     // Find the file editor that is currently visible.
 126     var fileEditorEl =
 127         document.querySelector('.function:not([hidden]) > textarea');
 128     // Rejoin args with pipe (|) -- there is only one argument, and it can
 129     // contain the pipe character.
 130     fileEditorEl.value = args.join('|');
 131   } else if (command == 'LIST') {
 132     var listDirOutputEl = document.getElementById('listDirOutput');
 133
 134     // NOTE: files with | in their names will be incorrectly split. Fixing this
 135     // is left as an exercise for the reader.
 136
 137     // Remove all children of this element...
 138     while (listDirOutputEl.firstChild) {
 139       listDirOutputEl.removeChild(listDirOutputEl.firstChild);
 140     }
 141
 142     if (args.length) {
 143       // Add new <li> elements for each file.
 144       for (var i = 0; i < args.length; ++i) {
 145         var itemEl = document.createElement('li');
 146         itemEl.textContent = args[i];
 147         listDirOutputEl.appendChild(itemEl);
 148       }
 149     } else {
 150       var itemEl = document.createElement('li');
 151       itemEl.textContent = '<empty directory>';
 152       listDirOutputEl.appendChild(itemEl);
 153     }
 154   }
 155 }