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/* |
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* write-bytes: Functions to turn data into bytes. |
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* Copyright (c) 2017 Rafael da Silva Rocha. |
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* https://github.com/rochars/byte-data |
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*/ |
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const floats = require("../src/floats.js"); |
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const intBits = require("int-bits"); |
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function write64BitFloat(bytes, numbers, i, j) { |
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let bits = floats.toFloat64(numbers[i]); |
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j = write32Bit(bytes, bits, 1, j); |
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return write32Bit(bytes, bits, 0, j); |
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} |
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// https://github.com/majimboo/c-struct |
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function write48Bit(bytes, numbers, i, j) { |
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bytes[j++] = numbers[i] & 0xFF; |
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bytes[j++] = numbers[i] >> 8 & 0xFF; |
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bytes[j++] = numbers[i] >> 16 & 0xFF; |
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bytes[j++] = numbers[i] >> 24 & 0xFF; |
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bytes[j++] = numbers[i] / 0x100000000 & 0xFF; |
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bytes[j++] = numbers[i] / 0x10000000000 & 0xFF; |
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return j; |
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} |
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// https://github.com/majimboo/c-struct |
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function write40Bit(bytes, numbers, i, j) { |
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bytes[j++] = numbers[i] & 0xFF; |
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bytes[j++] = numbers[i] >> 8 & 0xFF; |
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bytes[j++] = numbers[i] >> 16 & 0xFF; |
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bytes[j++] = numbers[i] >> 24 & 0xFF; |
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bytes[j++] = numbers[i] / 0x100000000 & 0xFF; |
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return j; |
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} |
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function write32BitFloat(bytes, numbers, i, j) { |
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let bits = intBits.unpack(numbers[i]); |
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bytes[j++] = bits & 0xFF; |
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bytes[j++] = bits >>> 8 & 0xFF; |
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bytes[j++] = bits >>> 16 & 0xFF; |
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bytes[j++] = bits >>> 24 & 0xFF; |
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return j; |
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} |
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function write32Bit(bytes, numbers, i, j) { |
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bytes[j++] = numbers[i] & 0xFF; |
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bytes[j++] = numbers[i] >>> 8 & 0xFF; |
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bytes[j++] = numbers[i] >>> 16 & 0xFF; |
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bytes[j++] = numbers[i] >>> 24 & 0xFF; |
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return j; |
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} |
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function write24Bit(bytes, numbers, i, j) { |
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bytes[j++] = numbers[i] & 0xFF; |
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bytes[j++] = numbers[i] >>> 8 & 0xFF; |
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bytes[j++] = numbers[i] >>> 16 & 0xFF; |
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return j; |
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} |
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function write16Bit(bytes, numbers, i, j) { |
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bytes[j++] = numbers[i] & 0xFF; |
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bytes[j++] = numbers[i] >>> 8 & 0xFF; |
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return j; |
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} |
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function write16BitFloat(bytes, numbers, i, j) { |
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let bits = floats.toHalf(numbers[i]); |
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bytes[j++] = bits >>> 8 & 0xFF; |
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bytes[j++] = bits & 0xFF; |
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return j; |
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} |
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function write8Bit(bytes, numbers, i, j) { |
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bytes[j++] = numbers[i] & 0xFF; |
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return j; |
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} |
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function write4Bit(bytes, numbers, i, j) { |
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bytes[j++] = numbers[i] & 0xF; |
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return j; |
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} |
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function write2Bit(bytes, numbers, i, j) { |
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bytes[j++] = numbers[i] < 0 ? numbers[i] + 4 : numbers[i]; |
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return j; |
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} |
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function write1Bit(bytes, numbers, i, j) { |
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bytes[j++] = numbers[i] ? 1 : 0; |
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return j; |
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} |
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function writeString(bytes, string, i, j) { |
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bytes[j++] = string.charCodeAt(i); |
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return j; |
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} |
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module.exports.write64BitFloat = write64BitFloat; |
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module.exports.write48Bit = write48Bit; |
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module.exports.write40Bit = write40Bit; |
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module.exports.write32BitFloat = write32BitFloat; |
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module.exports.write32Bit = write32Bit; |
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module.exports.write24Bit = write24Bit; |
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module.exports.write16Bit = write16Bit; |
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module.exports.write16BitFloat = write16BitFloat; |
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module.exports.write8Bit = write8Bit; |
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module.exports.write4Bit = write4Bit; |
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module.exports.write2Bit = write2Bit; |
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module.exports.write1Bit = write1Bit; |
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module.exports.writeString = writeString; |
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