tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
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dataview.js (2402B)

      1 function typeName(typedArrayCtor) {
      2  return typedArrayCtor.name.slice(0, -"Array".length);
      3 }
      4 
      5 const nativeIsLittleEndian = new Uint8Array(new Uint16Array([1]).buffer)[0] === 1;
      6 
      7 function toEndianess(type, v, littleEndian) {
      8  // Disable Ion compilation to call the native, non-inlined DataView functions.
      9  with ({}); // no-ion
     10  assertEq(inIon() !== true, true);
     11 
     12  let dv = new DataView(new ArrayBuffer(type.BYTES_PER_ELEMENT));
     13 
     14  let name = typeName(type);
     15  dv[`set${name}`](0, v, nativeIsLittleEndian);
     16  return dv[`get${name}`](0, littleEndian);
     17 }
     18 
     19 function toLittleEndian(type, v) {
     20  return toEndianess(type, v, true);
     21 }
     22 
     23 function toBigEndian(type, v) {
     24  return toEndianess(type, v, false);
     25 }
     26 
     27 // Shared test data for various DataView tests.
     28 function createTestData() {
     29  const tests = [
     30    {
     31      type: Int8Array,
     32      values: [-128, -127, -2, -1, 0, 1, 2, 126, 127],
     33    },
     34    {
     35      type: Uint8Array,
     36      values: [0, 1, 2, 126, 127, 128, 254, 255],
     37    },
     38    {
     39      type: Int16Array,
     40      values: [-32768, -32767, -2, -1, 0, 1, 2, 32766, 32767],
     41    },
     42    {
     43      type: Uint16Array,
     44      values: [0, 1, 2, 32766, 32767, 32768, 65534, 65535],
     45    },
     46    {
     47      type: Int32Array,
     48      values: [-2147483648, -2147483647, -2, -1, 0, 1, 2, 2147483646, 2147483647],
     49    },
     50    {
     51      type: Uint32Array,
     52      values: [0, 1, 2, 2147483646, 2147483647],  // Representable as Int32
     53    },
     54    {
     55      type: Uint32Array,
     56      values: [0, 1, 2, 2147483646, 2147483647, 2147483648, 4294967294, 4294967295],
     57    },
     58    {
     59      type: Float16Array,
     60      values: [-NaN, -Infinity, -0.5, -0, +0, 0.5, Infinity, NaN],
     61    },
     62    {
     63      type: Float32Array,
     64      values: [-NaN, -Infinity, -0.5, -0, +0, 0.5, Infinity, NaN],
     65    },
     66    {
     67      type: Float64Array,
     68      values: [-NaN, -Infinity, -0.5, -0, +0, 0.5, Infinity, NaN],
     69    },
     70    {
     71      type: BigInt64Array,
     72      values: [-9223372036854775808n, -9223372036854775807n, -2n, -1n, 0n, 1n, 2n, 9223372036854775806n, 9223372036854775807n],
     73    },
     74    {
     75      type: BigUint64Array,
     76      values: [0n, 1n, 2n, 9223372036854775806n, 9223372036854775807n, 9223372036854775808n, 18446744073709551614n, 18446744073709551615n],
     77    },
     78  ];
     79 
     80  tests.forEach(data => {
     81    data.littleEndian = data.values.map(v => toLittleEndian(data.type, v));
     82    data.bigEndian = data.values.map(v => toBigEndian(data.type, v));
     83  });
     84 
     85  return tests;
     86 }