test_arraybufferinputstream.html

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<!--

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<head>

  <title>ArrayBuffer stream test</title>

  <script src="/tests/SimpleTest/SimpleTest.js"></script>

  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />

<script type="text/javascript">

function detachArrayBuffer(ab)

  var w = new Worker("data:application/javascript,");

  w.postMessage(ab, [ab]);

function test()

  var ab = new ArrayBuffer(4000);

  var ta = new Uint8Array(ab);

  ta[0] = 'a'.charCodeAt(0);

  ta[1] = 'b'.charCodeAt(0);

  const Cc = SpecialPowers.Cc, Ci = SpecialPowers.Ci;

  var abis = Cc["@mozilla.org/io/arraybuffer-input-stream;1"]

               .createInstance(Ci.nsIArrayBufferInputStream);

  var sis = Cc["@mozilla.org/scriptableinputstream;1"]

              .createInstance(Ci.nsIScriptableInputStream);

  sis.init(abis);

  is(sis.read(1), "", "should read no data from an uninitialized ABIS");

  abis.setData(ab, 0, 256 * 1024);

  is(sis.read(1), "a", "should read 'a' after init");

  detachArrayBuffer(ab);

  SpecialPowers.forceGC();

  SpecialPowers.forceGC();

try

    is(sis.read(1), "b", "should read 'b' after detaching buffer");

  catch (e)

    ok(false, "reading from stream should have worked");

  // A regression test for bug 1265076.  Previously, overflowing

  // the internal buffer from readSegments would cause incorrect

  // copying.  The constant mirrors the value in

  // ArrayBufferInputStream::readSegments.

  var size = 8192;

  ab = new ArrayBuffer(2 * size);

  ta = new Uint8Array(ab);

  var i;

  for (i = 0; i < size; ++i) {

    ta[i] = 'x'.charCodeAt(0);

  for (i = 0; i < size; ++i) {

    ta[size + i] = 'y'.charCodeAt(0);

  abis = Cc["@mozilla.org/io/arraybuffer-input-stream;1"]

           .createInstance(Ci.nsIArrayBufferInputStream);

  abis.setData(ab, 0, 2 * size);

  sis = Cc["@mozilla.org/scriptableinputstream;1"]

          .createInstance(Ci.nsIScriptableInputStream);

  sis.init(abis);

  var result = sis.read(2 * size);

  is(result, "x".repeat(size) + "y".repeat(size), "correctly read the data");

test();

</script>

</head>

<body>

<p id="display"></p>

<div id="content" style="display: none"></div>

<pre id="test">

</pre>

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