27 lines
452 B
JavaScript
27 lines
452 B
JavaScript
module.exports = encode
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var MSB = 0x80
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, REST = 0x7F
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, MSBALL = ~REST
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, INT = Math.pow(2, 31)
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function encode(num, out, offset) {
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out = out || []
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offset = offset || 0
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var oldOffset = offset
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while(num >= INT) {
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out[offset++] = (num & 0xFF) | MSB
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num /= 128
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}
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while(num & MSBALL) {
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out[offset++] = (num & 0xFF) | MSB
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num >>>= 7
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}
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out[offset] = num | 0
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encode.bytes = offset - oldOffset + 1
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return out
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}
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