| 'use strict'; |
| |
| var assert = require("assert"); |
| |
| // JavaScript is numerically challenged |
| var SHIFT_LEFT_32 = (1 << 16) * (1 << 16); |
| var SHIFT_RIGHT_32 = 1 / SHIFT_LEFT_32; |
| |
| // The maximum contiguous integer that can be held in a IEEE754 double |
| var MAX_INT = 0x1fffffffffffff; |
| |
| function isContiguousInt(val) { |
| return val <= MAX_INT && val >= -MAX_INT; |
| } |
| |
| function assertContiguousInt(val) { |
| assert(isContiguousInt(val), "number cannot be represented as a contiguous integer"); |
| } |
| |
| module.exports.isContiguousInt = isContiguousInt; |
| module.exports.assertContiguousInt = assertContiguousInt; |
| |
| // Fill in the regular procedures |
| ['UInt', 'Int'].forEach(function (sign) { |
| var suffix = sign + '8'; |
| module.exports['read' + suffix] = |
| Buffer.prototype['read' + suffix].call; |
| module.exports['write' + suffix] = |
| Buffer.prototype['write' + suffix].call; |
| |
| ['16', '32'].forEach(function (size) { |
| ['LE', 'BE'].forEach(function (endian) { |
| var suffix = sign + size + endian; |
| var read = Buffer.prototype['read' + suffix]; |
| module.exports['read' + suffix] = |
| function (buf, offset, noAssert) { |
| return read.call(buf, offset, noAssert); |
| }; |
| var write = Buffer.prototype['write' + suffix]; |
| module.exports['write' + suffix] = |
| function (buf, val, offset, noAssert) { |
| return write.call(buf, val, offset, noAssert); |
| }; |
| }); |
| }); |
| }); |
| |
| // Check that a value is an integer within the given range |
| function check_int(val, min, max) { |
| assert.ok(typeof(val) == 'number' && val >= min && val <= max && Math.floor(val) === val, "not a number in the required range"); |
| } |
| |
| function readUInt24BE(buf, offset, noAssert) { |
| return buf.readUInt8(offset, noAssert) << 16 | buf.readUInt16BE(offset + 1, noAssert); |
| } |
| module.exports.readUInt24BE = readUInt24BE; |
| |
| function writeUInt24BE(buf, val, offset, noAssert) { |
| if (!noAssert) { |
| check_int(val, 0, 0xffffff); |
| assert.ok(offset + 3 <= buf.length, "attempt to write beyond end of buffer"); |
| } |
| |
| buf.writeUInt8(val >>> 16, offset, noAssert); |
| buf.writeUInt16BE(val & 0xffff, offset + 1, noAssert); |
| } |
| module.exports.writeUInt24BE = writeUInt24BE; |
| |
| function readUInt40BE(buf, offset, noAssert) { |
| return (buf.readUInt8(offset, noAssert) || 0) * SHIFT_LEFT_32 + buf.readUInt32BE(offset + 1, noAssert); |
| } |
| module.exports.readUInt40BE = readUInt40BE; |
| |
| function writeUInt40BE(buf, val, offset, noAssert) { |
| if (!noAssert) { |
| check_int(val, 0, 0xffffffffff); |
| assert.ok(offset + 5 <= buf.length, "attempt to write beyond end of buffer"); |
| } |
| |
| buf.writeUInt8(Math.floor(val * SHIFT_RIGHT_32), offset, noAssert); |
| buf.writeInt32BE(val & -1, offset + 1, noAssert); |
| } |
| module.exports.writeUInt40BE = writeUInt40BE; |
| |
| function readUInt48BE(buf, offset, noAssert) { |
| return buf.readUInt16BE(offset, noAssert) * SHIFT_LEFT_32 + buf.readUInt32BE(offset + 2, noAssert); |
| } |
| module.exports.readUInt48BE = readUInt48BE; |
| |
| function writeUInt48BE(buf, val, offset, noAssert) { |
| if (!noAssert) { |
| check_int(val, 0, 0xffffffffffff); |
| assert.ok(offset + 6 <= buf.length, "attempt to write beyond end of buffer"); |
| } |
| |
| buf.writeUInt16BE(Math.floor(val * SHIFT_RIGHT_32), offset, noAssert); |
| buf.writeInt32BE(val & -1, offset + 2, noAssert); |
| } |
| module.exports.writeUInt48BE = writeUInt48BE; |
| |
| function readUInt56BE(buf, offset, noAssert) { |
| return ((buf.readUInt8(offset, noAssert) || 0) << 16 | buf.readUInt16BE(offset + 1, noAssert)) * SHIFT_LEFT_32 + buf.readUInt32BE(offset + 3, noAssert); |
| } |
| module.exports.readUInt56BE = readUInt56BE; |
| |
| function writeUInt56BE(buf, val, offset, noAssert) { |
| if (!noAssert) { |
| check_int(val, 0, 0xffffffffffffff); |
| assert.ok(offset + 7 <= buf.length, "attempt to write beyond end of buffer"); |
| } |
| |
| if (val < 0x100000000000000) { |
| var hi = Math.floor(val * SHIFT_RIGHT_32); |
| buf.writeUInt8(hi >>> 16, offset, noAssert); |
| buf.writeUInt16BE(hi & 0xffff, offset + 1, noAssert); |
| buf.writeInt32BE(val & -1, offset + 3, noAssert); |
| } else { |
| // Special case because 2^56-1 gets rounded up to 2^56 |
| buf[offset] = 0xff; |
| buf[offset+1] = 0xff; |
| buf[offset+2] = 0xff; |
| buf[offset+3] = 0xff; |
| buf[offset+4] = 0xff; |
| buf[offset+5] = 0xff; |
| buf[offset+6] = 0xff; |
| } |
| } |
| module.exports.writeUInt56BE = writeUInt56BE; |
| |
| function readUInt64BE(buf, offset, noAssert) { |
| return buf.readUInt32BE(offset, noAssert) * SHIFT_LEFT_32 + buf.readUInt32BE(offset + 4, noAssert); |
| } |
| module.exports.readUInt64BE = readUInt64BE; |
| |
| function writeUInt64BE(buf, val, offset, noAssert) { |
| if (!noAssert) { |
| check_int(val, 0, 0xffffffffffffffff); |
| assert.ok(offset + 8 <= buf.length, "attempt to write beyond end of buffer"); |
| } |
| |
| if (val < 0x10000000000000000) { |
| buf.writeUInt32BE(Math.floor(val * SHIFT_RIGHT_32), offset, noAssert); |
| buf.writeInt32BE(val & -1, offset + 4, noAssert); |
| } else { |
| // Special case because 2^64-1 gets rounded up to 2^64 |
| buf[offset] = 0xff; |
| buf[offset+1] = 0xff; |
| buf[offset+2] = 0xff; |
| buf[offset+3] = 0xff; |
| buf[offset+4] = 0xff; |
| buf[offset+5] = 0xff; |
| buf[offset+6] = 0xff; |
| buf[offset+7] = 0xff; |
| } |
| } |
| module.exports.writeUInt64BE = writeUInt64BE; |
| |
| function readUInt24LE(buf, offset, noAssert) { |
| return buf.readUInt8(offset + 2, noAssert) << 16 | buf.readUInt16LE(offset, noAssert); |
| } |
| module.exports.readUInt24LE = readUInt24LE; |
| |
| function writeUInt24LE(buf, val, offset, noAssert) { |
| if (!noAssert) { |
| check_int(val, 0, 0xffffff); |
| assert.ok(offset + 3 <= buf.length, "attempt to write beyond end of buffer"); |
| } |
| |
| buf.writeUInt16LE(val & 0xffff, offset, noAssert); |
| buf.writeUInt8(val >>> 16, offset + 2, noAssert); |
| } |
| module.exports.writeUInt24LE = writeUInt24LE; |
| |
| function readUInt40LE(buf, offset, noAssert) { |
| return (buf.readUInt8(offset + 4, noAssert) || 0) * SHIFT_LEFT_32 + buf.readUInt32LE(offset, noAssert); |
| } |
| module.exports.readUInt40LE = readUInt40LE; |
| |
| function writeUInt40LE(buf, val, offset, noAssert) { |
| if (!noAssert) { |
| check_int(val, 0, 0xffffffffff); |
| assert.ok(offset + 5 <= buf.length, "attempt to write beyond end of buffer"); |
| } |
| |
| buf.writeInt32LE(val & -1, offset, noAssert); |
| buf.writeUInt8(Math.floor(val * SHIFT_RIGHT_32), offset + 4, noAssert); |
| } |
| module.exports.writeUInt40LE = writeUInt40LE; |
| |
| function readUInt48LE(buf, offset, noAssert) { |
| return buf.readUInt16LE(offset + 4, noAssert) * SHIFT_LEFT_32 + buf.readUInt32LE(offset, noAssert); |
| } |
| module.exports.readUInt48LE = readUInt48LE; |
| |
| function writeUInt48LE(buf, val, offset, noAssert) { |
| if (!noAssert) { |
| check_int(val, 0, 0xffffffffffff); |
| assert.ok(offset + 6 <= buf.length, "attempt to write beyond end of buffer"); |
| } |
| |
| buf.writeInt32LE(val & -1, offset, noAssert); |
| buf.writeUInt16LE(Math.floor(val * SHIFT_RIGHT_32), offset + 4, noAssert); |
| } |
| module.exports.writeUInt48LE = writeUInt48LE; |
| |
| function readUInt56LE(buf, offset, noAssert) { |
| return ((buf.readUInt8(offset + 6, noAssert) || 0) << 16 | buf.readUInt16LE(offset + 4, noAssert)) * SHIFT_LEFT_32 + buf.readUInt32LE(offset, noAssert); |
| } |
| module.exports.readUInt56LE = readUInt56LE; |
| |
| function writeUInt56LE(buf, val, offset, noAssert) { |
| if (!noAssert) { |
| check_int(val, 0, 0xffffffffffffff); |
| assert.ok(offset + 7 <= buf.length, "attempt to write beyond end of buffer"); |
| } |
| |
| if (val < 0x100000000000000) { |
| buf.writeInt32LE(val & -1, offset, noAssert); |
| var hi = Math.floor(val * SHIFT_RIGHT_32); |
| buf.writeUInt16LE(hi & 0xffff, offset + 4, noAssert); |
| buf.writeUInt8(hi >>> 16, offset + 6, noAssert); |
| } else { |
| // Special case because 2^56-1 gets rounded up to 2^56 |
| buf[offset] = 0xff; |
| buf[offset+1] = 0xff; |
| buf[offset+2] = 0xff; |
| buf[offset+3] = 0xff; |
| buf[offset+4] = 0xff; |
| buf[offset+5] = 0xff; |
| buf[offset+6] = 0xff; |
| } |
| } |
| module.exports.writeUInt56LE = writeUInt56LE; |
| |
| function readUInt64LE(buf, offset, noAssert) { |
| return buf.readUInt32LE(offset + 4, noAssert) * SHIFT_LEFT_32 + buf.readUInt32LE(offset, noAssert); |
| } |
| module.exports.readUInt64LE = readUInt64LE; |
| |
| function writeUInt64LE(buf, val, offset, noAssert) { |
| if (!noAssert) { |
| check_int(val, 0, 0xffffffffffffffff); |
| assert.ok(offset + 8 <= buf.length, "attempt to write beyond end of buffer"); |
| } |
| |
| if (val < 0x10000000000000000) { |
| buf.writeInt32LE(val & -1, offset, noAssert); |
| buf.writeUInt32LE(Math.floor(val * SHIFT_RIGHT_32), offset + 4, noAssert); |
| } else { |
| // Special case because 2^64-1 gets rounded up to 2^64 |
| buf[offset] = 0xff; |
| buf[offset+1] = 0xff; |
| buf[offset+2] = 0xff; |
| buf[offset+3] = 0xff; |
| buf[offset+4] = 0xff; |
| buf[offset+5] = 0xff; |
| buf[offset+6] = 0xff; |
| buf[offset+7] = 0xff; |
| } |
| } |
| module.exports.writeUInt64LE = writeUInt64LE; |
| |
| |
| function readInt24BE(buf, offset, noAssert) { |
| return (buf.readInt8(offset, noAssert) << 16) + buf.readUInt16BE(offset + 1, noAssert); |
| } |
| module.exports.readInt24BE = readInt24BE; |
| |
| function writeInt24BE(buf, val, offset, noAssert) { |
| if (!noAssert) { |
| check_int(val, -0x800000, 0x7fffff); |
| assert.ok(offset + 3 <= buf.length, "attempt to write beyond end of buffer"); |
| } |
| |
| buf.writeInt8(val >> 16, offset, noAssert); |
| buf.writeUInt16BE(val & 0xffff, offset + 1, noAssert); |
| } |
| module.exports.writeInt24BE = writeInt24BE; |
| |
| function readInt40BE(buf, offset, noAssert) { |
| return (buf.readInt8(offset, noAssert) || 0) * SHIFT_LEFT_32 + buf.readUInt32BE(offset + 1, noAssert); |
| } |
| module.exports.readInt40BE = readInt40BE; |
| |
| function writeInt40BE(buf, val, offset, noAssert) { |
| if (!noAssert) { |
| check_int(val, -0x8000000000, 0x7fffffffff); |
| assert.ok(offset + 5 <= buf.length, "attempt to write beyond end of buffer"); |
| } |
| |
| buf.writeInt8(Math.floor(val * SHIFT_RIGHT_32), offset, noAssert); |
| buf.writeInt32BE(val & -1, offset + 1, noAssert); |
| } |
| module.exports.writeInt40BE = writeInt40BE; |
| |
| function readInt48BE(buf, offset, noAssert) { |
| return buf.readInt16BE(offset, noAssert) * SHIFT_LEFT_32 + buf.readUInt32BE(offset + 2, noAssert); |
| } |
| module.exports.readInt48BE = readInt48BE; |
| |
| function writeInt48BE(buf, val, offset, noAssert) { |
| if (!noAssert) { |
| check_int(val, -0x800000000000, 0x7fffffffffff); |
| assert.ok(offset + 6 <= buf.length, "attempt to write beyond end of buffer"); |
| } |
| |
| buf.writeInt16BE(Math.floor(val * SHIFT_RIGHT_32), offset, noAssert); |
| buf.writeInt32BE(val & -1, offset + 2, noAssert); |
| } |
| module.exports.writeInt48BE = writeInt48BE; |
| |
| function readInt56BE(buf, offset, noAssert) { |
| return (((buf.readInt8(offset, noAssert) || 0) << 16) + buf.readUInt16BE(offset + 1, noAssert)) * SHIFT_LEFT_32 + buf.readUInt32BE(offset + 3, noAssert); |
| } |
| module.exports.readInt56BE = readInt56BE; |
| |
| function writeInt56BE(buf, val, offset, noAssert) { |
| if (!noAssert) { |
| check_int(val, -0x800000000000000, 0x7fffffffffffff); |
| assert.ok(offset + 7 <= buf.length, "attempt to write beyond end of buffer"); |
| } |
| |
| if (val < 0x80000000000000) { |
| var hi = Math.floor(val * SHIFT_RIGHT_32); |
| buf.writeInt8(hi >> 16, offset, noAssert); |
| buf.writeUInt16BE(hi & 0xffff, offset + 1, noAssert); |
| buf.writeInt32BE(val & -1, offset + 3, noAssert); |
| } else { |
| // Special case because 2^55-1 gets rounded up to 2^55 |
| buf[offset] = 0x7f; |
| buf[offset+1] = 0xff; |
| buf[offset+2] = 0xff; |
| buf[offset+3] = 0xff; |
| buf[offset+4] = 0xff; |
| buf[offset+5] = 0xff; |
| buf[offset+6] = 0xff; |
| } |
| } |
| module.exports.writeInt56BE = writeInt56BE; |
| |
| function readInt64BE(buf, offset, noAssert) { |
| return buf.readInt32BE(offset, noAssert) * SHIFT_LEFT_32 + buf.readUInt32BE(offset + 4, noAssert); |
| } |
| module.exports.readInt64BE = readInt64BE; |
| |
| function writeInt64BE(buf, val, offset, noAssert) { |
| if (!noAssert) { |
| check_int(val, -0x800000000000000000, 0x7fffffffffffffff); |
| assert.ok(offset + 8 <= buf.length, "attempt to write beyond end of buffer"); |
| } |
| |
| if (val < 0x8000000000000000) { |
| buf.writeInt32BE(Math.floor(val * SHIFT_RIGHT_32), offset, noAssert); |
| buf.writeInt32BE(val & -1, offset + 4, noAssert); |
| } else { |
| // Special case because 2^63-1 gets rounded up to 2^63 |
| buf[offset] = 0x7f; |
| buf[offset+1] = 0xff; |
| buf[offset+2] = 0xff; |
| buf[offset+3] = 0xff; |
| buf[offset+4] = 0xff; |
| buf[offset+5] = 0xff; |
| buf[offset+6] = 0xff; |
| buf[offset+7] = 0xff; |
| } |
| } |
| module.exports.writeInt64BE = writeInt64BE; |
| |
| function readInt24LE(buf, offset, noAssert) { |
| return (buf.readInt8(offset + 2, noAssert) << 16) + buf.readUInt16LE(offset, noAssert); |
| } |
| module.exports.readInt24LE = readInt24LE; |
| |
| function writeInt24LE(buf, val, offset, noAssert) { |
| if (!noAssert) { |
| check_int(val, -0x800000, 0x7fffff); |
| assert.ok(offset + 3 <= buf.length, "attempt to write beyond end of buffer"); |
| } |
| |
| buf.writeUInt16LE(val & 0xffff, offset, noAssert); |
| buf.writeInt8(val >> 16, offset + 2, noAssert); |
| } |
| module.exports.writeInt24LE = writeInt24LE; |
| |
| function readInt40LE(buf, offset, noAssert) { |
| return (buf.readInt8(offset + 4, noAssert) || 0) * SHIFT_LEFT_32 + buf.readUInt32LE(offset, noAssert); |
| } |
| module.exports.readInt40LE = readInt40LE; |
| |
| function writeInt40LE(buf, val, offset, noAssert) { |
| if (!noAssert) { |
| check_int(val, -0x8000000000, 0x7fffffffff); |
| assert.ok(offset + 5 <= buf.length, "attempt to write beyond end of buffer"); |
| } |
| |
| buf.writeInt32LE(val & -1, offset, noAssert); |
| buf.writeInt8(Math.floor(val * SHIFT_RIGHT_32), offset + 4, noAssert); |
| } |
| module.exports.writeInt40LE = writeInt40LE; |
| |
| function readInt48LE(buf, offset, noAssert) { |
| return buf.readInt16LE(offset + 4, noAssert) * SHIFT_LEFT_32 + buf.readUInt32LE(offset, noAssert); |
| } |
| module.exports.readInt48LE = readInt48LE; |
| |
| function writeInt48LE(buf, val, offset, noAssert) { |
| if (!noAssert) { |
| check_int(val, -0x800000000000, 0x7fffffffffff); |
| assert.ok(offset + 6 <= buf.length, "attempt to write beyond end of buffer"); |
| } |
| |
| buf.writeInt32LE(val & -1, offset, noAssert); |
| buf.writeInt16LE(Math.floor(val * SHIFT_RIGHT_32), offset + 4, noAssert); |
| } |
| module.exports.writeInt48LE = writeInt48LE; |
| |
| function readInt56LE(buf, offset, noAssert) { |
| return (((buf.readInt8(offset + 6, noAssert) || 0) << 16) + buf.readUInt16LE(offset + 4, noAssert)) * SHIFT_LEFT_32 + buf.readUInt32LE(offset, noAssert); |
| } |
| module.exports.readInt56LE = readInt56LE; |
| |
| function writeInt56LE(buf, val, offset, noAssert) { |
| if (!noAssert) { |
| check_int(val, -0x80000000000000, 0x7fffffffffffff); |
| assert.ok(offset + 7 <= buf.length, "attempt to write beyond end of buffer"); |
| } |
| |
| if (val < 0x80000000000000) { |
| buf.writeInt32LE(val & -1, offset, noAssert); |
| var hi = Math.floor(val * SHIFT_RIGHT_32); |
| buf.writeUInt16LE(hi & 0xffff, offset + 4, noAssert); |
| buf.writeInt8(hi >> 16, offset + 6, noAssert); |
| } else { |
| // Special case because 2^55-1 gets rounded up to 2^55 |
| buf[offset] = 0xff; |
| buf[offset+1] = 0xff; |
| buf[offset+2] = 0xff; |
| buf[offset+3] = 0xff; |
| buf[offset+4] = 0xff; |
| buf[offset+5] = 0xff; |
| buf[offset+6] = 0x7f; |
| } |
| } |
| module.exports.writeInt56LE = writeInt56LE; |
| |
| function readInt64LE(buf, offset, noAssert) { |
| return buf.readInt32LE(offset + 4, noAssert) * SHIFT_LEFT_32 + buf.readUInt32LE(offset, noAssert); |
| } |
| module.exports.readInt64LE = readInt64LE; |
| |
| function writeInt64LE(buf, val, offset, noAssert) { |
| if (!noAssert) { |
| check_int(val, -0x8000000000000000, 0x7fffffffffffffff); |
| assert.ok(offset + 8 <= buf.length, "attempt to write beyond end of buffer"); |
| } |
| |
| if (val < 0x8000000000000000) { |
| buf.writeInt32LE(val & -1, offset, noAssert); |
| buf.writeInt32LE(Math.floor(val * SHIFT_RIGHT_32), offset + 4, noAssert); |
| } else { |
| // Special case because 2^55-1 gets rounded up to 2^55 |
| buf[offset] = 0xff; |
| buf[offset+1] = 0xff; |
| buf[offset+2] = 0xff; |
| buf[offset+3] = 0xff; |
| buf[offset+4] = 0xff; |
| buf[offset+5] = 0xff; |
| buf[offset+6] = 0xff; |
| buf[offset+7] = 0x7f; |
| } |
| } |
| module.exports.writeInt64LE = writeInt64LE; |