146 lines
3.2 KiB
JavaScript
146 lines
3.2 KiB
JavaScript
/**
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* Get one bit on a byte
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*
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* This is a byte of bits ===> ABCDEFGH
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*
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* getBIT(ABCDEFGH, 3) ==> E
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*/
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function getBIT(byte, order)
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{
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return (byte >> order) & 1
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}
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/**
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* Update one bit on a byte
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*
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* This is a byte of bits ===> ABCDEFGH
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*
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* setBIT(ABCDEFGH, 3, 0) ==> ABCD0FGH
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* setBIT(ABCDEFGH, 3, 1) ==> ABCD1FGH
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*/
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function setBIT(byte, order, value)
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{
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return (
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value == 0
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) ? (
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byte & (( 1 << order ) ^ 255)
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) : (
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byte | ( 1 << order )
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);
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};
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/**
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* Explode byte of per bits and given Function
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* and anonymous returning value is result
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*
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* This is a byte of bits ===> ABCDEFGH
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*
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* explodeBits(ABCDEFGH, (A, B, C, D, E, F, G, H) => {
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* return A
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* }) ===> A
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*
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*/
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function explodeBits(bytes, map)
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{
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return map(
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(bytes >> 7 & 1),
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(bytes >> 6 & 1),
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(bytes >> 5 & 1),
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(bytes >> 4 & 1),
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(bytes >> 3 & 1),
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(bytes >> 2 & 1),
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(bytes >> 1 & 1),
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bytes & 1
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)
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}
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/**
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* Explode byte of per bits and given Function
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* and anonymous returning value is result
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*
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* This is a byte of bits ===> ABCDEFGH
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*
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* implodeByte(A,B,C,D,E,F,G,H) ===> ABCDEFGH
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*/
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function implodeByte(a,b,c,d,e,f,g,h)
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{
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return (a << 7) | (b << 6) | (c << 5) | (d << 4) | (e << 3) | (f << 2) | (g << 1) | h
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}
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/**
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* Explode byte of per bits and given Function
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* and anonymous returning value is result
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*
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* This is a byte of bits ===> ABCDEFGH
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*
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* explodeBits(ABCDEFGH, (A0000000, 0B000000, 00C00000, 000D0000, 0000E000, 00000F00, 000000G0, 0000000H) => {
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* return A
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* }) ===> A
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*
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*/
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function explodeBitValue(bytes, map)
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{
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return map(
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(bytes >> 7 & 1) << 7,
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(bytes >> 6 & 1) << 6,
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(bytes >> 5 & 1) << 5,
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(bytes >> 4 & 1) << 4,
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(bytes >> 3 & 1) << 3,
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(bytes >> 2 & 1) << 2,
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(bytes >> 1 & 1) << 1,
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bytes & 1
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)
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}
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/**
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* Explode byte of per bits and given Function
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* and anonymous returning value is result
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*
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* This is a byte of bits ===> ABCDEFGH
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*
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* implodeByte(A0000000, 0B000000, 00C00000, 000D0000, 0000E000, 00000F00, 000000G0, 0000000H) ===> ABCDEFGH
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*/
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function implodeBitValues(a,b,c,d,e,f,g,h)
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{
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return a | b | c | d | e | f | g | h
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}
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/**
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* This is a byte of bits ===> ABCDEFGH
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*
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* rightShift(ABCDEFGH) ==> HABCDEFG
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*/
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function rightShift(byte)
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{
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return explodeBits(byte, (a,b,c,d,e,f,g,h) => {
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return implodeByte(h,a,b,c,d,e,f,g)
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})
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}
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/**
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* This is a byte of bits ===> ABCDEFGH
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*
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* leftShift(ABCDEFGH) ==> BCDEFGHA
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*/
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function leftShift(byte)
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{
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return explodeBits(byte, (a,b,c,d,e,f,g,h) => {
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return implodeByte(b,c,d,e,f,g,h,a)
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})
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}
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/**
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* eachBlock([A,B,C,D,E,F,G,H], 3) ==> [A,B,C],[D,E,F],[G,H]
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*/
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function * eachBlock(bytesArray, size)
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{
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let current = 0;
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while(1)
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{
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let currentOffset = current * size;
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let currentOffsetEnd = current * size + size;
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let result = bytesArray.slice(
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currentOffset,
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currentOffsetEnd
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);
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if(result.length + size <= size)
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{
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return result
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}else{
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current++;
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yield result
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}
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}
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} |