851 lines
32 KiB
C
851 lines
32 KiB
C
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/* -*- indent-tabs-mode: t; tab-width: 8; c-basic-offset: 8; -*- */
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/* ts A91016 : libburn/ecma130ab.c is the replacement for old libburn/lec.c
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Copyright 2009, Thomas Schmitt <scdbackup@gmx.net>, libburnia-project.org
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This code module implements the production of RSPC parity bytes (P- and Q-
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parity) and the scrambling of raw CD-ROM sectors as specified in ECMA-130:
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http://www.ecma-international.org/publications/files/ECMA-ST/Ecma-130.pdf
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The following statements about Galois Fields have been learned mostly from
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http://www.cs.utk.edu/~plank/plank/papers/CS-96-332.pdf
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by James S. Plank after an e-mail exchange with Norbert Preining.
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The output has been compared with the output of the old code of libburn
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which was labeled "borrowed HEAVILY from cdrdao" and claimed by Joerg
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Schilling to stem from code by Heiko Eissfeldt.
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-------------------------------------------------------------------------
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Note: In this text, "^" denotes exponentiation and not the binary exor
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operation. Confusingly in the C code "^" is said exor.
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Note: This is not C1, C2 which is rather mentioned in ECMA-130 Annex C and
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always performed inside the drive.
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-------------------------------------------------------------------------
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RSPC resp. P- and Q-Parity
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ECMA-130 Annex A prescribes to compute the parity bytes for P-columns and
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Q-diagonals by RSPC based on a Galois Field GF(2^8) with enumerating
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polynomials x^8+x^4+x^3+x^2+1 (i.e. 0x11d) and x^1 (i.e. 0x02).
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Bytes 12 to 2075 of a audio-sized sector get ordered in two byte words
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as 24 rows and 43 columns. Then this matrix is split into a LSB matrix
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and a MSB matrix of the same layout. Parity bytes are to be computed
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from these 8-bit values.
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2 P-bytes cover each column of 24 bytes. They get appended to the matrix
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as rows 24 and 25.
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2 Q-bytes cover each the 26 diagonals of the extended matrix.
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Both parity byte pairs have to be computed so that extended rows or
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diagonals match this linear equation:
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H x V = (0,0)
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H is a 2-row matrix of size n matching the length of the V ectors
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[ 1 1 ... 1 1 ]
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[ x^(n-1) x^(n-2) x^1 1 ]
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Vp represents a P-row. It is a byte vector consisting of row bytes at
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position 0 to 23 and the two parity bytes which shall be determined
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at position 24 and 25. So Hp has 26 columns.
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Vq represents a Q-diagonal. It is a byte vector consisting of diagonal
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bytes at position 0 to 42 and the two parity bytes at position 43 and 44.
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So Hq has 45 columns. The Q-diagonals cover P-parity bytes.
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By applying some high school algebra one gets the parity bytes b0, b1 of
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vector V = (n_payload_bytes, b0 , b1) as
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b0 = ( H[n] * SUM(n_payload_bytes) - H[0..(n-1)] x n_payload_bytes )
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/ (H[n+1] - H[n])
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b1 = - SUM(n_payload_bytes) - b0
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H[i] is the i-the element of the second row of matrix H. E.g. H[0] = x^(n-1)
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The result has to be computed by Galois field arithmetics. See below.
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The P-parity bytes of each column get reunited as LSB and MSB of two words.
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word1 gets written to positions 1032 to 1074, word0 to 1075 to 1117.
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The Q-parity bytes of each diagonal get reunited too. word1 goes to 1118
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to 1143, word0 to 1144 to 1169.
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>>> I do not read this swap of word1 and word0 from ECMA-130 Annex A.
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>>> But the new output matches the old output only if it is done that way.
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>>> See correctness reservation below.
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Algebra on Galois fields is the same as on Rational Numbers.
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But arithmetics is defined by operations on polynomials rather than the
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usual integer arithmetics on binary numbers.
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Addition and subtraction are identical with the binary exor operator.
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Multiplication and division would demand polynomial division, e.g. by the
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euclidian algorithm. The computing path over logarithms and powers follows
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algebra and allows to reduce the arithmetic task to table lookups, additions
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modulo 255, and exor operations. Note that the logarithms are natural
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numbers, not polynomials. They get added or subtracted by the usual addition
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(not by exor) and their polynomial power depends on their value modulo 255.
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Needed are a logarithm table and a power table (or inverse logarithm table)
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for Galois Field GF(2^8) which will serve to perform the peculiar
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multiplication and division operation of Galois fields.
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The power table is simply an enumeration of x^n accorting to
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GF-multiplication. It also serves as second line of matrix H for the parity
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equations:
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Hp[i] = gfpow[25-i] , i out of {0,..,25}
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Hq[i] = gfpow[44-i] , i out of {0,..,44}
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The logarithm table is the inverse permutation of the power table.
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Some simplifications apply to the implementation:
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In the world of Galois fields there is no difference between - and +.
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The term (H[n+1] - H[n]) is constant: 3.
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-------------------------------------------------------------------------
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Scrambling
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ECMA-130 Annex B prescribes to exor the byte stream of an audio-sized sector
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with a sequence of pseudo random bytes. It mentions polynomial x^15+x+1 and
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a 15-bit register.
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It shows a diagram of a Feedback Shift Register with 16 bit boxes, though.
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Comparing this with explanations in
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http://www.newwaveinstruments.com/resources/articles/m_sequence_linear_feedback_shift_register_lfsr.htm
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one can recognize the diagram as a Fibonacci Implementation. But there seems
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really to be one bit box too many.
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The difference of both lengths is expressed in function next_bit() by
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the constants 0x3fff,0x4000 for 15 bit versus 0x7fff,0x8000 for 16 bits.
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Comparing the output of both alternatives with the old scrambler output
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lets 15 bit win for now.
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So the prescription is to start with 15 bit value 1, to use the lowest bit
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as output, to shift the bits down by one, to exor the output bit with the
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next lowest bit, and to put that exor result into bit 14 of the register.
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-------------------------------------------------------------------------
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Correctness Reservation
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In both cases, parity and scrambling, the goal for now is to replicate the
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output of the dismissed old lec.c by output which is based on published
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specs and own implementation code. Whether they comply to ECMA-130 is a
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different question which can only be answered by real test cases for
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raw CD recording.
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Of course this implementation will be corrected so that it really complies
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to ECMA-130 as soon as evidence emerges that it does not yet.
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*/
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/* ------------------------------------------------------------------------- */
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/* Power and logarithm tables for GF(2^8), parity matrices for ECMA-130.
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Generated by burn_rspc_setup_tables() and burn_rspc_print_tables().
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The highest possible sum of gflog[] values is is 508. So the table gfpow[]
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with period 255 was manually unrolled to 509 elements to avoid one modulo
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255 operation in burn_rspc_mult().
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Proposed by D. Hugh Redelmeier.
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*/
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static unsigned char gfpow[509] = {
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1, 2, 4, 8, 16, 32, 64, 128, 29, 58,
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116, 232, 205, 135, 19, 38, 76, 152, 45, 90,
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180, 117, 234, 201, 143, 3, 6, 12, 24, 48,
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96, 192, 157, 39, 78, 156, 37, 74, 148, 53,
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106, 212, 181, 119, 238, 193, 159, 35, 70, 140,
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5, 10, 20, 40, 80, 160, 93, 186, 105, 210,
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185, 111, 222, 161, 95, 190, 97, 194, 153, 47,
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94, 188, 101, 202, 137, 15, 30, 60, 120, 240,
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253, 231, 211, 187, 107, 214, 177, 127, 254, 225,
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223, 163, 91, 182, 113, 226, 217, 175, 67, 134,
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17, 34, 68, 136, 13, 26, 52, 104, 208, 189,
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103, 206, 129, 31, 62, 124, 248, 237, 199, 147,
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59, 118, 236, 197, 151, 51, 102, 204, 133, 23,
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46, 92, 184, 109, 218, 169, 79, 158, 33, 66,
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132, 21, 42, 84, 168, 77, 154, 41, 82, 164,
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85, 170, 73, 146, 57, 114, 228, 213, 183, 115,
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230, 209, 191, 99, 198, 145, 63, 126, 252, 229,
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215, 179, 123, 246, 241, 255, 227, 219, 171, 75,
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150, 49, 98, 196, 149, 55, 110, 220, 165, 87,
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174, 65, 130, 25, 50, 100, 200, 141, 7, 14,
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28, 56, 112, 224, 221, 167, 83, 166, 81, 162,
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89, 178, 121, 242, 249, 239, 195, 155, 43, 86,
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172, 69, 138, 9, 18, 36, 72, 144, 61, 122,
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244, 245, 247, 243, 251, 235, 203, 139, 11, 22,
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44, 88, 176, 125, 250, 233, 207, 131, 27, 54,
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108, 216, 173, 71, 142,
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1, 2, 4, 8, 16, 32, 64, 128, 29, 58,
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116, 232, 205, 135, 19, 38, 76, 152, 45, 90,
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180, 117, 234, 201, 143, 3, 6, 12, 24, 48,
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96, 192, 157, 39, 78, 156, 37, 74, 148, 53,
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106, 212, 181, 119, 238, 193, 159, 35, 70, 140,
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5, 10, 20, 40, 80, 160, 93, 186, 105, 210,
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185, 111, 222, 161, 95, 190, 97, 194, 153, 47,
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94, 188, 101, 202, 137, 15, 30, 60, 120, 240,
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253, 231, 211, 187, 107, 214, 177, 127, 254, 225,
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223, 163, 91, 182, 113, 226, 217, 175, 67, 134,
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17, 34, 68, 136, 13, 26, 52, 104, 208, 189,
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103, 206, 129, 31, 62, 124, 248, 237, 199, 147,
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59, 118, 236, 197, 151, 51, 102, 204, 133, 23,
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46, 92, 184, 109, 218, 169, 79, 158, 33, 66,
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132, 21, 42, 84, 168, 77, 154, 41, 82, 164,
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85, 170, 73, 146, 57, 114, 228, 213, 183, 115,
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230, 209, 191, 99, 198, 145, 63, 126, 252, 229,
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215, 179, 123, 246, 241, 255, 227, 219, 171, 75,
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150, 49, 98, 196, 149, 55, 110, 220, 165, 87,
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174, 65, 130, 25, 50, 100, 200, 141, 7, 14,
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28, 56, 112, 224, 221, 167, 83, 166, 81, 162,
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89, 178, 121, 242, 249, 239, 195, 155, 43, 86,
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172, 69, 138, 9, 18, 36, 72, 144, 61, 122,
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244, 245, 247, 243, 251, 235, 203, 139, 11, 22,
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44, 88, 176, 125, 250, 233, 207, 131, 27, 54,
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108, 216, 173, 71,
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};
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static unsigned char gflog[256] = {
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0, 0, 1, 25, 2, 50, 26, 198, 3, 223,
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51, 238, 27, 104, 199, 75, 4, 100, 224, 14,
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52, 141, 239, 129, 28, 193, 105, 248, 200, 8,
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76, 113, 5, 138, 101, 47, 225, 36, 15, 33,
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53, 147, 142, 218, 240, 18, 130, 69, 29, 181,
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194, 125, 106, 39, 249, 185, 201, 154, 9, 120,
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77, 228, 114, 166, 6, 191, 139, 98, 102, 221,
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48, 253, 226, 152, 37, 179, 16, 145, 34, 136,
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54, 208, 148, 206, 143, 150, 219, 189, 241, 210,
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19, 92, 131, 56, 70, 64, 30, 66, 182, 163,
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195, 72, 126, 110, 107, 58, 40, 84, 250, 133,
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186, 61, 202, 94, 155, 159, 10, 21, 121, 43,
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78, 212, 229, 172, 115, 243, 167, 87, 7, 112,
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192, 247, 140, 128, 99, 13, 103, 74, 222, 237,
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49, 197, 254, 24, 227, 165, 153, 119, 38, 184,
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180, 124, 17, 68, 146, 217, 35, 32, 137, 46,
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55, 63, 209, 91, 149, 188, 207, 205, 144, 135,
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151, 178, 220, 252, 190, 97, 242, 86, 211, 171,
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20, 42, 93, 158, 132, 60, 57, 83, 71, 109,
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65, 162, 31, 45, 67, 216, 183, 123, 164, 118,
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196, 23, 73, 236, 127, 12, 111, 246, 108, 161,
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59, 82, 41, 157, 85, 170, 251, 96, 134, 177,
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187, 204, 62, 90, 203, 89, 95, 176, 156, 169,
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160, 81, 11, 245, 22, 235, 122, 117, 44, 215,
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79, 174, 213, 233, 230, 231, 173, 232, 116, 214,
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244, 234, 168, 80, 88, 175
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};
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#define Libburn_use_h_matriceS 1
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#ifdef Libburn_use_h_matriceS
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/* On my AMD 2x64 bit 3000 MHz processor h[i] costs about 7 % more time
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than using gfpow[25-i] resp. gfpow[44-1]. I blame this on the more
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condensed data representation which slightly increases the rate of cache
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hits.
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Nevertheless this effect is very likely depending on the exact cache
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size and architecture. In general, using h[] saves more than 8000
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subtractions per sector.
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*/
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/* Parity matrices H as prescribed by ECMA-130 Annex A.
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Actually just reverted order start pieces of gfpow[].
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*/
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static unsigned char h26[26] = {
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3, 143, 201, 234, 117, 180, 90, 45, 152, 76,
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38, 19, 135, 205, 232, 116, 58, 29, 128, 64,
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32, 16, 8, 4, 2, 1,
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};
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static unsigned char h45[45] = {
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238, 119, 181, 212, 106, 53, 148, 74, 37, 156,
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78, 39, 157, 192, 96, 48, 24, 12, 6, 3,
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143, 201, 234, 117, 180, 90, 45, 152, 76, 38,
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19, 135, 205, 232, 116, 58, 29, 128, 64, 32,
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16, 8, 4, 2, 1,
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};
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#endif /* Libburn_use_h_matriceS */
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/* Pseudo-random bytes which of course are exactly the same as with the
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previously used code.
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Generated by function print_ecma_130_scrambler().
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*/
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static unsigned char ecma_130_annex_b[2340] = {
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1, 128, 0, 96, 0, 40, 0, 30, 128, 8,
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96, 6, 168, 2, 254, 129, 128, 96, 96, 40,
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40, 30, 158, 136, 104, 102, 174, 170, 252, 127,
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1, 224, 0, 72, 0, 54, 128, 22, 224, 14,
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200, 4, 86, 131, 126, 225, 224, 72, 72, 54,
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182, 150, 246, 238, 198, 204, 82, 213, 253, 159,
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1, 168, 0, 126, 128, 32, 96, 24, 40, 10,
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158, 135, 40, 98, 158, 169, 168, 126, 254, 160,
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64, 120, 48, 34, 148, 25, 175, 74, 252, 55,
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1, 214, 128, 94, 224, 56, 72, 18, 182, 141,
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182, 229, 182, 203, 54, 215, 86, 222, 190, 216,
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112, 90, 164, 59, 59, 83, 83, 125, 253, 225,
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129, 136, 96, 102, 168, 42, 254, 159, 0, 104,
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0, 46, 128, 28, 96, 9, 232, 6, 206, 130,
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212, 97, 159, 104, 104, 46, 174, 156, 124, 105,
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225, 238, 200, 76, 86, 181, 254, 247, 0, 70,
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128, 50, 224, 21, 136, 15, 38, 132, 26, 227,
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75, 9, 247, 70, 198, 178, 210, 245, 157, 135,
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41, 162, 158, 249, 168, 66, 254, 177, 128, 116,
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96, 39, 104, 26, 174, 139, 60, 103, 81, 234,
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188, 79, 49, 244, 20, 71, 79, 114, 180, 37,
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183, 91, 54, 187, 86, 243, 126, 197, 224, 83,
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8, 61, 198, 145, 146, 236, 109, 141, 237, 165,
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141, 187, 37, 179, 91, 53, 251, 87, 3, 126,
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129, 224, 96, 72, 40, 54, 158, 150, 232, 110,
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206, 172, 84, 125, 255, 97, 128, 40, 96, 30,
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168, 8, 126, 134, 160, 98, 248, 41, 130, 158,
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225, 168, 72, 126, 182, 160, 118, 248, 38, 194,
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154, 209, 171, 28, 127, 73, 224, 54, 200, 22,
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214, 142, 222, 228, 88, 75, 122, 183, 99, 54,
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169, 214, 254, 222, 192, 88, 80, 58, 188, 19,
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49, 205, 212, 85, 159, 127, 40, 32, 30, 152,
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8, 106, 134, 175, 34, 252, 25, 129, 202, 224,
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87, 8, 62, 134, 144, 98, 236, 41, 141, 222,
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229, 152, 75, 42, 183, 95, 54, 184, 22, 242,
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142, 197, 164, 83, 59, 125, 211, 97, 157, 232,
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105, 142, 174, 228, 124, 75, 97, 247, 104, 70,
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174, 178, 252, 117, 129, 231, 32, 74, 152, 55,
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42, 150, 159, 46, 232, 28, 78, 137, 244, 102,
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199, 106, 210, 175, 29, 188, 9, 177, 198, 244,
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82, 199, 125, 146, 161, 173, 184, 125, 178, 161,
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181, 184, 119, 50, 166, 149, 186, 239, 51, 12,
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21, 197, 207, 19, 20, 13, 207, 69, 148, 51,
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47, 85, 220, 63, 25, 208, 10, 220, 7, 25,
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194, 138, 209, 167, 28, 122, 137, 227, 38, 201,
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218, 214, 219, 30, 219, 72, 91, 118, 187, 102,
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243, 106, 197, 239, 19, 12, 13, 197, 197, 147,
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19, 45, 205, 221, 149, 153, 175, 42, 252, 31,
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1, 200, 0, 86, 128, 62, 224, 16, 72, 12,
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54, 133, 214, 227, 30, 201, 200, 86, 214, 190,
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222, 240, 88, 68, 58, 179, 83, 53, 253, 215,
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1, 158, 128, 104, 96, 46, 168, 28, 126, 137,
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224, 102, 200, 42, 214, 159, 30, 232, 8, 78,
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134, 180, 98, 247, 105, 134, 174, 226, 252, 73,
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129, 246, 224, 70, 200, 50, 214, 149, 158, 239,
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40, 76, 30, 181, 200, 119, 22, 166, 142, 250,
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228, 67, 11, 113, 199, 100, 82, 171, 125, 191,
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97, 176, 40, 116, 30, 167, 72, 122, 182, 163,
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54, 249, 214, 194, 222, 209, 152, 92, 106, 185,
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239, 50, 204, 21, 149, 207, 47, 20, 28, 15,
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73, 196, 54, 211, 86, 221, 254, 217, 128, 90,
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224, 59, 8, 19, 70, 141, 242, 229, 133, 139,
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35, 39, 89, 218, 186, 219, 51, 27, 85, 203,
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127, 23, 96, 14, 168, 4, 126, 131, 96, 97,
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232, 40, 78, 158, 180, 104, 119, 110, 166, 172,
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122, 253, 227, 1, 137, 192, 102, 208, 42, 220,
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31, 25, 200, 10, 214, 135, 30, 226, 136, 73,
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166, 182, 250, 246, 195, 6, 209, 194, 220, 81,
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153, 252, 106, 193, 239, 16, 76, 12, 53, 197,
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215, 19, 30, 141, 200, 101, 150, 171, 46, 255,
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92, 64, 57, 240, 18, 196, 13, 147, 69, 173,
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243, 61, 133, 209, 163, 28, 121, 201, 226, 214,
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201, 158, 214, 232, 94, 206, 184, 84, 114, 191,
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101, 176, 43, 52, 31, 87, 72, 62, 182, 144,
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118, 236, 38, 205, 218, 213, 155, 31, 43, 72,
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31, 118, 136, 38, 230, 154, 202, 235, 23, 15,
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78, 132, 52, 99, 87, 105, 254, 174, 192, 124,
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80, 33, 252, 24, 65, 202, 176, 87, 52, 62,
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151, 80, 110, 188, 44, 113, 221, 228, 89, 139,
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122, 231, 99, 10, 169, 199, 62, 210, 144, 93,
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172, 57, 189, 210, 241, 157, 132, 105, 163, 110,
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249, 236, 66, 205, 241, 149, 132, 111, 35, 108,
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25, 237, 202, 205, 151, 21, 174, 143, 60, 100,
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17, 235, 76, 79, 117, 244, 39, 7, 90, 130,
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187, 33, 179, 88, 117, 250, 167, 3, 58, 129,
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211, 32, 93, 216, 57, 154, 146, 235, 45, 143,
|
|
93, 164, 57, 187, 82, 243, 125, 133, 225, 163,
|
|
8, 121, 198, 162, 210, 249, 157, 130, 233, 161,
|
|
142, 248, 100, 66, 171, 113, 191, 100, 112, 43,
|
|
100, 31, 107, 72, 47, 118, 156, 38, 233, 218,
|
|
206, 219, 20, 91, 79, 123, 116, 35, 103, 89,
|
|
234, 186, 207, 51, 20, 21, 207, 79, 20, 52,
|
|
15, 87, 68, 62, 179, 80, 117, 252, 39, 1,
|
|
218, 128, 91, 32, 59, 88, 19, 122, 141, 227,
|
|
37, 137, 219, 38, 219, 90, 219, 123, 27, 99,
|
|
75, 105, 247, 110, 198, 172, 82, 253, 253, 129,
|
|
129, 160, 96, 120, 40, 34, 158, 153, 168, 106,
|
|
254, 175, 0, 124, 0, 33, 192, 24, 80, 10,
|
|
188, 7, 49, 194, 148, 81, 175, 124, 124, 33,
|
|
225, 216, 72, 90, 182, 187, 54, 243, 86, 197,
|
|
254, 211, 0, 93, 192, 57, 144, 18, 236, 13,
|
|
141, 197, 165, 147, 59, 45, 211, 93, 157, 249,
|
|
169, 130, 254, 225, 128, 72, 96, 54, 168, 22,
|
|
254, 142, 192, 100, 80, 43, 124, 31, 97, 200,
|
|
40, 86, 158, 190, 232, 112, 78, 164, 52, 123,
|
|
87, 99, 126, 169, 224, 126, 200, 32, 86, 152,
|
|
62, 234, 144, 79, 44, 52, 29, 215, 73, 158,
|
|
182, 232, 118, 206, 166, 212, 122, 223, 99, 24,
|
|
41, 202, 158, 215, 40, 94, 158, 184, 104, 114,
|
|
174, 165, 188, 123, 49, 227, 84, 73, 255, 118,
|
|
192, 38, 208, 26, 220, 11, 25, 199, 74, 210,
|
|
183, 29, 182, 137, 182, 230, 246, 202, 198, 215,
|
|
18, 222, 141, 152, 101, 170, 171, 63, 63, 80,
|
|
16, 60, 12, 17, 197, 204, 83, 21, 253, 207,
|
|
1, 148, 0, 111, 64, 44, 48, 29, 212, 9,
|
|
159, 70, 232, 50, 206, 149, 148, 111, 47, 108,
|
|
28, 45, 201, 221, 150, 217, 174, 218, 252, 91,
|
|
1, 251, 64, 67, 112, 49, 228, 20, 75, 79,
|
|
119, 116, 38, 167, 90, 250, 187, 3, 51, 65,
|
|
213, 240, 95, 4, 56, 3, 82, 129, 253, 160,
|
|
65, 184, 48, 114, 148, 37, 175, 91, 60, 59,
|
|
81, 211, 124, 93, 225, 249, 136, 66, 230, 177,
|
|
138, 244, 103, 7, 106, 130, 175, 33, 188, 24,
|
|
113, 202, 164, 87, 59, 126, 147, 96, 109, 232,
|
|
45, 142, 157, 164, 105, 187, 110, 243, 108, 69,
|
|
237, 243, 13, 133, 197, 163, 19, 57, 205, 210,
|
|
213, 157, 159, 41, 168, 30, 254, 136, 64, 102,
|
|
176, 42, 244, 31, 7, 72, 2, 182, 129, 182,
|
|
224, 118, 200, 38, 214, 154, 222, 235, 24, 79,
|
|
74, 180, 55, 55, 86, 150, 190, 238, 240, 76,
|
|
68, 53, 243, 87, 5, 254, 131, 0, 97, 192,
|
|
40, 80, 30, 188, 8, 113, 198, 164, 82, 251,
|
|
125, 131, 97, 161, 232, 120, 78, 162, 180, 121,
|
|
183, 98, 246, 169, 134, 254, 226, 192, 73, 144,
|
|
54, 236, 22, 205, 206, 213, 148, 95, 47, 120,
|
|
28, 34, 137, 217, 166, 218, 250, 219, 3, 27,
|
|
65, 203, 112, 87, 100, 62, 171, 80, 127, 124,
|
|
32, 33, 216, 24, 90, 138, 187, 39, 51, 90,
|
|
149, 251, 47, 3, 92, 1, 249, 192, 66, 208,
|
|
49, 156, 20, 105, 207, 110, 212, 44, 95, 93,
|
|
248, 57, 130, 146, 225, 173, 136, 125, 166, 161,
|
|
186, 248, 115, 2, 165, 193, 187, 16, 115, 76,
|
|
37, 245, 219, 7, 27, 66, 139, 113, 167, 100,
|
|
122, 171, 99, 63, 105, 208, 46, 220, 28, 89,
|
|
201, 250, 214, 195, 30, 209, 200, 92, 86, 185,
|
|
254, 242, 192, 69, 144, 51, 44, 21, 221, 207,
|
|
25, 148, 10, 239, 71, 12, 50, 133, 213, 163,
|
|
31, 57, 200, 18, 214, 141, 158, 229, 168, 75,
|
|
62, 183, 80, 118, 188, 38, 241, 218, 196, 91,
|
|
19, 123, 77, 227, 117, 137, 231, 38, 202, 154,
|
|
215, 43, 30, 159, 72, 104, 54, 174, 150, 252,
|
|
110, 193, 236, 80, 77, 252, 53, 129, 215, 32,
|
|
94, 152, 56, 106, 146, 175, 45, 188, 29, 177,
|
|
201, 180, 86, 247, 126, 198, 160, 82, 248, 61,
|
|
130, 145, 161, 172, 120, 125, 226, 161, 137, 184,
|
|
102, 242, 170, 197, 191, 19, 48, 13, 212, 5,
|
|
159, 67, 40, 49, 222, 148, 88, 111, 122, 172,
|
|
35, 61, 217, 209, 154, 220, 107, 25, 239, 74,
|
|
204, 55, 21, 214, 143, 30, 228, 8, 75, 70,
|
|
183, 114, 246, 165, 134, 251, 34, 195, 89, 145,
|
|
250, 236, 67, 13, 241, 197, 132, 83, 35, 125,
|
|
217, 225, 154, 200, 107, 22, 175, 78, 252, 52,
|
|
65, 215, 112, 94, 164, 56, 123, 82, 163, 125,
|
|
185, 225, 178, 200, 117, 150, 167, 46, 250, 156,
|
|
67, 41, 241, 222, 196, 88, 83, 122, 189, 227,
|
|
49, 137, 212, 102, 223, 106, 216, 47, 26, 156,
|
|
11, 41, 199, 94, 210, 184, 93, 178, 185, 181,
|
|
178, 247, 53, 134, 151, 34, 238, 153, 140, 106,
|
|
229, 239, 11, 12, 7, 69, 194, 179, 17, 181,
|
|
204, 119, 21, 230, 143, 10, 228, 7, 11, 66,
|
|
135, 113, 162, 164, 121, 187, 98, 243, 105, 133,
|
|
238, 227, 12, 73, 197, 246, 211, 6, 221, 194,
|
|
217, 145, 154, 236, 107, 13, 239, 69, 140, 51,
|
|
37, 213, 219, 31, 27, 72, 11, 118, 135, 102,
|
|
226, 170, 201, 191, 22, 240, 14, 196, 4, 83,
|
|
67, 125, 241, 225, 132, 72, 99, 118, 169, 230,
|
|
254, 202, 192, 87, 16, 62, 140, 16, 101, 204,
|
|
43, 21, 223, 79, 24, 52, 10, 151, 71, 46,
|
|
178, 156, 117, 169, 231, 62, 202, 144, 87, 44,
|
|
62, 157, 208, 105, 156, 46, 233, 220, 78, 217,
|
|
244, 90, 199, 123, 18, 163, 77, 185, 245, 178,
|
|
199, 53, 146, 151, 45, 174, 157, 188, 105, 177,
|
|
238, 244, 76, 71, 117, 242, 167, 5, 186, 131,
|
|
51, 33, 213, 216, 95, 26, 184, 11, 50, 135,
|
|
85, 162, 191, 57, 176, 18, 244, 13, 135, 69,
|
|
162, 179, 57, 181, 210, 247, 29, 134, 137, 162,
|
|
230, 249, 138, 194, 231, 17, 138, 140, 103, 37,
|
|
234, 155, 15, 43, 68, 31, 115, 72, 37, 246,
|
|
155, 6, 235, 66, 207, 113, 148, 36, 111, 91,
|
|
108, 59, 109, 211, 109, 157, 237, 169, 141, 190,
|
|
229, 176, 75, 52, 55, 87, 86, 190, 190, 240,
|
|
112, 68, 36, 51, 91, 85, 251, 127, 3, 96,
|
|
1, 232, 0, 78, 128, 52, 96, 23, 104, 14,
|
|
174, 132, 124, 99, 97, 233, 232, 78, 206, 180,
|
|
84, 119, 127, 102, 160, 42, 248, 31, 2, 136,
|
|
1, 166, 128, 122, 224, 35, 8, 25, 198, 138,
|
|
210, 231, 29, 138, 137, 167, 38, 250, 154, 195,
|
|
43, 17, 223, 76, 88, 53, 250, 151, 3, 46,
|
|
129, 220, 96, 89, 232, 58, 206, 147, 20, 109,
|
|
207, 109, 148, 45, 175, 93, 188, 57, 177, 210,
|
|
244, 93, 135, 121, 162, 162, 249, 185, 130, 242,
|
|
225, 133, 136, 99, 38, 169, 218, 254, 219, 0,
|
|
91, 64, 59, 112, 19, 100, 13, 235, 69, 143,
|
|
115, 36, 37, 219, 91, 27, 123, 75, 99, 119,
|
|
105, 230, 174, 202, 252, 87, 1, 254, 128, 64,
|
|
96, 48, 40, 20, 30, 143, 72, 100, 54, 171,
|
|
86, 255, 126, 192, 32, 80, 24, 60, 10, 145,
|
|
199, 44, 82, 157, 253, 169, 129, 190, 224, 112,
|
|
72, 36, 54, 155, 86, 235, 126, 207, 96, 84,
|
|
40, 63, 94, 144, 56, 108, 18, 173, 205, 189,
|
|
149, 177, 175, 52, 124, 23, 97, 206, 168, 84,
|
|
126, 191, 96, 112, 40, 36, 30, 155, 72, 107,
|
|
118, 175, 102, 252, 42, 193, 223, 16, 88, 12,
|
|
58, 133, 211, 35, 29, 217, 201, 154, 214, 235,
|
|
30, 207, 72, 84, 54, 191, 86, 240, 62, 196,
|
|
16, 83, 76, 61, 245, 209, 135, 28, 98, 137,
|
|
233, 166, 206, 250, 212, 67, 31, 113, 200, 36,
|
|
86, 155, 126, 235, 96, 79, 104, 52, 46, 151,
|
|
92, 110, 185, 236, 114, 205, 229, 149, 139, 47,
|
|
39, 92, 26, 185, 203, 50, 215, 85, 158, 191,
|
|
40, 112, 30, 164, 8, 123, 70, 163, 114, 249,
|
|
229, 130, 203, 33, 151, 88, 110, 186, 172, 115,
|
|
61, 229, 209, 139, 28, 103, 73, 234, 182, 207,
|
|
54, 212, 22, 223, 78, 216, 52, 90, 151, 123,
|
|
46, 163, 92, 121, 249, 226, 194, 201, 145, 150,
|
|
236, 110, 205, 236, 85, 141, 255, 37, 128, 27,
|
|
32, 11, 88, 7, 122, 130, 163, 33, 185, 216,
|
|
114, 218, 165, 155, 59, 43, 83, 95, 125, 248,
|
|
33, 130, 152, 97, 170, 168, 127, 62, 160, 16,
|
|
120, 12, 34, 133, 217, 163, 26, 249, 203, 2,
|
|
215, 65, 158, 176, 104, 116, 46, 167, 92, 122,
|
|
185, 227, 50, 201, 213, 150, 223, 46, 216, 28,
|
|
90, 137, 251, 38, 195, 90, 209, 251, 28, 67,
|
|
73, 241, 246, 196, 70, 211, 114, 221, 229, 153
|
|
};
|
|
|
|
|
|
/* ------------------------------------------------------------------------- */
|
|
|
|
|
|
/* This is the new implementation of P- and Q-parity generation.
|
|
It needs about the same computing time as the old implementation (both
|
|
with gcc -O2 on AMD 64 bit). Measurements indicate that about 280 MIPS
|
|
are needed for 48x CD speed (7.1 MB/s).
|
|
*/
|
|
|
|
static unsigned char burn_rspc_mult(unsigned char a, unsigned char b)
|
|
{
|
|
if (a == 0 || b == 0)
|
|
return 0;
|
|
/* Optimization of (a == 0 || b == 0) by D. Hugh Redelmeier
|
|
if((((int)a - 1) | ((int)b - 1)) < 0)
|
|
return 0;
|
|
*/
|
|
|
|
return gfpow[gflog[a] + gflog[b]];
|
|
/* % 255 not necessary because gfpow is unrolled up to index 510 */
|
|
}
|
|
|
|
|
|
/* Divide by polynomial 0x03. Derived from burn_rspc_div() and using the
|
|
unrolled size of the gfpow[] array.
|
|
*/
|
|
static unsigned char burn_rspc_div_3(unsigned char a)
|
|
{
|
|
if (a == 0)
|
|
return 0;
|
|
return gfpow[230 + gflog[a]];
|
|
}
|
|
|
|
|
|
static void burn_rspc_p0p1(unsigned char *sector, int col,
|
|
unsigned char *p0_lsb, unsigned char *p0_msb,
|
|
unsigned char *p1_lsb, unsigned char *p1_msb)
|
|
{
|
|
unsigned char *start, b;
|
|
unsigned int i, sum_v_lsb = 0, sum_v_msb = 0;
|
|
unsigned int hxv_lsb = 0, hxv_msb = 0;
|
|
|
|
start = sector + 12 + 2 * col;
|
|
for(i = 0; i < 24; i++) {
|
|
b = *start;
|
|
sum_v_lsb ^= b;
|
|
|
|
#ifdef Libburn_use_h_matriceS
|
|
hxv_lsb ^= burn_rspc_mult(b, h26[i]);
|
|
#else
|
|
hxv_lsb ^= burn_rspc_mult(b, gfpow[25 - i]);
|
|
#endif
|
|
|
|
b = *(start + 1);
|
|
sum_v_msb ^= b;
|
|
|
|
#ifdef Libburn_use_h_matriceS
|
|
hxv_msb ^= burn_rspc_mult(b, h26[i]);
|
|
#else
|
|
hxv_msb ^= burn_rspc_mult(b, gfpow[25 - i]);
|
|
#endif
|
|
|
|
start += 86;
|
|
}
|
|
|
|
/* 3 = gfpow[1] ^ gfpow[0] , 2 = gfpow[1] */
|
|
*p0_lsb = burn_rspc_div_3(burn_rspc_mult(2, sum_v_lsb) ^ hxv_lsb);
|
|
*p0_msb = burn_rspc_div_3(burn_rspc_mult(2, sum_v_msb) ^ hxv_msb);
|
|
*p1_lsb = sum_v_lsb ^ *p0_lsb;
|
|
*p1_msb = sum_v_msb ^ *p0_msb;
|
|
}
|
|
|
|
|
|
void burn_rspc_parity_p(unsigned char *sector)
|
|
{
|
|
int i;
|
|
unsigned char p0_lsb, p0_msb, p1_lsb, p1_msb;
|
|
|
|
/* Loop over P columns */
|
|
for(i = 0; i < 43; i++) {
|
|
burn_rspc_p0p1(sector, i, &p0_lsb, &p0_msb, &p1_lsb, &p1_msb);
|
|
sector[2162 + 2 * i] = p0_lsb;
|
|
sector[2162 + 2 * i + 1] = p0_msb;
|
|
sector[2076 + 2 * i] = p1_lsb;
|
|
sector[2076 + 2 * i + 1] = p1_msb;
|
|
|
|
#ifdef Libburn_with_lec_generatoR
|
|
if(verbous) {
|
|
printf("p %2d : %2.2X %2.2X ", i,
|
|
(unsigned int) p0_lsb, (unsigned int) p0_msb);
|
|
printf("%2.2X %2.2X ",
|
|
(unsigned int) p1_lsb, (unsigned int) p1_msb);
|
|
printf("-> %d,%d\n", 2162 + 2 * i, 2076 + 2 * i);
|
|
}
|
|
#endif /* Libburn_with_lec_generatoR */
|
|
|
|
}
|
|
}
|
|
|
|
|
|
static void burn_rspc_q0q1(unsigned char *sector, int diag,
|
|
unsigned char *q0_lsb, unsigned char *q0_msb,
|
|
unsigned char *q1_lsb, unsigned char *q1_msb)
|
|
{
|
|
unsigned char *start, b;
|
|
unsigned int i, idx, sum_v_lsb = 0, sum_v_msb = 0;
|
|
unsigned int hxv_lsb = 0, hxv_msb = 0;
|
|
|
|
start = sector + 12;
|
|
idx = 2 * 43 * diag;
|
|
for(i = 0; i < 43; i++) {
|
|
if (idx >= 2236)
|
|
idx -= 2236;
|
|
b = start[idx];
|
|
sum_v_lsb ^= b;
|
|
|
|
#ifdef Libburn_use_h_matriceS
|
|
hxv_lsb ^= burn_rspc_mult(b, h45[i]);
|
|
#else
|
|
hxv_lsb ^= burn_rspc_mult(b, gfpow[44 - i]);
|
|
#endif
|
|
|
|
b = start[idx + 1];
|
|
sum_v_msb ^= b;
|
|
|
|
#ifdef Libburn_use_h_matriceS
|
|
hxv_msb ^= burn_rspc_mult(b, h45[i]);
|
|
#else
|
|
hxv_msb ^= burn_rspc_mult(b, gfpow[44 - i]);
|
|
#endif
|
|
|
|
idx += 88;
|
|
}
|
|
/* 3 = gfpow[1] ^ gfpow[0] , 2 = gfpow[1] */
|
|
*q0_lsb = burn_rspc_div_3(burn_rspc_mult(2, sum_v_lsb) ^ hxv_lsb);
|
|
*q0_msb = burn_rspc_div_3(burn_rspc_mult(2, sum_v_msb) ^ hxv_msb);
|
|
*q1_lsb = sum_v_lsb ^ *q0_lsb;
|
|
*q1_msb = sum_v_msb ^ *q0_msb;
|
|
}
|
|
|
|
|
|
void burn_rspc_parity_q(unsigned char *sector)
|
|
{
|
|
int i;
|
|
unsigned char q0_lsb, q0_msb, q1_lsb, q1_msb;
|
|
|
|
/* Loop over Q diagonals */
|
|
for(i = 0; i < 26; i++) {
|
|
burn_rspc_q0q1(sector, i, &q0_lsb, &q0_msb, &q1_lsb, &q1_msb);
|
|
sector[2300 + 2 * i] = q0_lsb;
|
|
sector[2300 + 2 * i + 1] = q0_msb;
|
|
sector[2248 + 2 * i] = q1_lsb;
|
|
sector[2248 + 2 * i + 1] = q1_msb;
|
|
|
|
#ifdef Libburn_with_lec_generatoR
|
|
if(verbous) {
|
|
printf("q %2d : %2.2X %2.2X ", i,
|
|
(unsigned int) q0_lsb, (unsigned int) q0_msb);
|
|
printf("%2.2X %2.2X ",
|
|
(unsigned int) q1_lsb, (unsigned int) q1_msb);
|
|
printf("-> %d,%d\n", 2300 + 2 * i, 2248 + 2 * i);
|
|
}
|
|
#endif /* Libburn_with_lec_generatoR */
|
|
|
|
}
|
|
}
|
|
|
|
/* ------------------------------------------------------------------------- */
|
|
|
|
|
|
/* The new implementation of the ECMA-130 Annex B scrambler.
|
|
It is totally unoptimized. One should make use of larger word operations.
|
|
Measurements indicate that about 50 MIPS are needed for 48x CD speed.
|
|
*/
|
|
|
|
void burn_ecma130_scramble(unsigned char *sector)
|
|
{
|
|
int i;
|
|
unsigned char *s;
|
|
|
|
s = sector + 12;
|
|
for (i = 0; i < 2340; i++)
|
|
s[i] ^= ecma_130_annex_b[i];
|
|
}
|
|
|
|
|
|
/* ------------------------------------------------------------------------- */
|
|
|
|
|
|
/* The following code is not needed for libburn but rather documents the
|
|
origin of the tables above. In libburn it will not be compiled.
|
|
*/
|
|
|
|
|
|
#ifdef Libburn_with_lec_generatoR
|
|
|
|
|
|
/* This function produced the content of gflog[] and gfpow[]
|
|
*/
|
|
static int burn_rspc_setup_tables(void)
|
|
{
|
|
unsigned int b, l;
|
|
|
|
memset(gflog, 0, sizeof(gflog));
|
|
memset(gfpow, 0, sizeof(gfpow));
|
|
b = 1;
|
|
for (l = 0; l < 255; l++) {
|
|
gfpow[l] = (unsigned char) b;
|
|
gflog[b] = (unsigned char) l;
|
|
b = b << 1;
|
|
if (b & 256)
|
|
b = b ^ 0x11d;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
|
|
/* This function printed the content of gflog[] and gfpow[] as C code
|
|
and compared the content with the tables of the old implementation.
|
|
h26[] and h45[] are reverted order copies of gfpow[]
|
|
*/
|
|
static int burn_rspc_print_tables(void)
|
|
{
|
|
int i;
|
|
|
|
printf("static unsigned char gfpow[255] = {");
|
|
printf("\n\t");
|
|
for(i= 0; i < 255; i++) {
|
|
printf("%3u, ", gfpow[i]);
|
|
|
|
#ifdef Libburn_with_old_lec_comparisoN
|
|
if(gfpow[i] != gf8_ilog[i])
|
|
fprintf(stderr, "*** ILOG %d : %d != %d ***\n", i, gfpow[i], gf8_ilog[i]);
|
|
#endif
|
|
|
|
if((i % 10) == 9)
|
|
printf("\n\t");
|
|
}
|
|
printf("\n};\n\n");
|
|
|
|
printf("static unsigned char gflog[256] = {");
|
|
printf("\n\t");
|
|
for(i= 0; i < 256; i++) {
|
|
printf(" %3u,", gflog[i]);
|
|
|
|
#ifdef Libburn_with_old_lec_comparisoN
|
|
if(gflog[i] != gf8_log[i])
|
|
fprintf(stderr, "*** LOG %d : %d != %d ***\n", i, gflog[i], gf8_log[i]);
|
|
#endif
|
|
|
|
if((i % 10) == 9)
|
|
printf("\n\t");
|
|
}
|
|
printf("\n};\n\n");
|
|
|
|
printf("static unsigned char h26[26] = {");
|
|
printf("\n\t");
|
|
for(i= 0; i < 26; i++) {
|
|
printf(" %3u,", gfpow[25 - i]);
|
|
if((i % 10) == 9)
|
|
printf("\n\t");
|
|
}
|
|
printf("\n};\n\n");
|
|
|
|
printf("static unsigned char h45[45] = {");
|
|
printf("\n\t");
|
|
for(i= 0; i < 45; i++) {
|
|
printf(" %3u,",gfpow[44 - i]);
|
|
if((i % 10) == 9)
|
|
printf("\n\t");
|
|
}
|
|
printf("\n};\n\n");
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
/* This code was used to generate the content of array ecma_130_annex_b[].
|
|
*/
|
|
static unsigned short ecma_130_fsr = 1;
|
|
|
|
static int next_bit(void)
|
|
{
|
|
int ret;
|
|
|
|
ret = ecma_130_fsr & 1;
|
|
ecma_130_fsr = (ecma_130_fsr >> 1) & 0x3fff;
|
|
if (ret ^ (ecma_130_fsr & 1))
|
|
ecma_130_fsr |= 0x4000;
|
|
return ret;
|
|
}
|
|
|
|
|
|
static int print_ecma_130_scrambler(void)
|
|
{
|
|
int i, j, b;
|
|
|
|
ecma_130_fsr = 1;
|
|
printf("static unsigned char ecma_130_annex_b[2340] = {");
|
|
printf("\n\t");
|
|
for (i = 0; i < 2340; i++) {
|
|
b = 0;
|
|
for (j = 0; j < 8; j++)
|
|
b |= next_bit() << j;
|
|
|
|
printf("%3u, ", b);
|
|
if ((i % 10) == 9)
|
|
printf("\n\t");
|
|
}
|
|
printf("\n};\n");
|
|
return 1;
|
|
}
|
|
|
|
|
|
#ifdef Libburn_with_general_rspc_diV
|
|
|
|
/* This is a general polynomial division function.
|
|
burn_rspc_div_3() has been derived from this by setting b to constant 3.
|
|
*/
|
|
static unsigned char burn_rspc_div(unsigned char a, unsigned char b)
|
|
{
|
|
int d;
|
|
|
|
if (a == 0)
|
|
return 0;
|
|
if (b == 0)
|
|
return -1;
|
|
d = gflog[a] - gflog[b];
|
|
if (d < 0)
|
|
d += 255;
|
|
return gfpow[d];
|
|
}
|
|
|
|
#endif /* Libburn_with_general_rspc_diV */
|
|
|
|
|
|
#endif /* Libburn_with_lec_generatoR */
|
|
|