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65 lines
1.3 KiB
C
65 lines
1.3 KiB
C
/* j/c/muk.c
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**
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*/
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#include "all.h"
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#include <murmur3.h>
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/* functions
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*/
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u3_noun
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u3qc_muk(u3_atom seed,
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u3_atom len,
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u3_atom key)
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{
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c3_w seed_w;
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c3_w len_w;
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c3_y *key_y;
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c3_w out_w;
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c3_assert( u3r_met(5, seed) <= 1 );
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c3_assert( u3r_met(0, len) <= 31 );
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c3_assert( u3r_met(3, key) <= len );
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seed_w = u3r_word(0, seed);
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len_w = u3r_word(0, len);
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// can't u3a_calloc 0 bytes
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//
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if ( 0 == len_w ) {
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key_y = 0;
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}
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else {
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key_y = u3a_calloc(sizeof(c3_y), len_w);
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}
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// Efficiency: unnecessary copy.
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//
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// We could calculate the hash directly against
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// the atom internals, a la u3r_mug
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//
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u3r_bytes(0, len_w, key_y, key);
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MurmurHash3_x86_32(key_y, len_w, seed_w, &out_w);
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u3a_free(key_y);
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return u3i_words(1, &out_w);
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}
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u3_noun
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u3wc_muk(u3_noun cor)
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{
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u3_noun seed, len, key;
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if ( (c3n == u3r_mean(cor, u3x_sam_2, &seed,
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u3x_sam_6, &len,
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u3x_sam_7, &key, 0)) ||
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(c3n == u3ud(seed)) ||
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(c3n == u3ud(len)) ||
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(c3n == u3ud(key)) )
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{
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return u3m_bail(c3__exit);
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} else {
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return u3qc_muk(seed, len, key);
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}
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}
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