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Removed fingerprint methods and fixed pending bugs.

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This commit is contained in:
davi
2008-04-28 01:18:23 +00:00
parent 522c66581e
commit b5cc0a8ea8
21 changed files with 6 additions and 743 deletions
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38
src/bdz_ph.c
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@@ -527,44 +527,6 @@ void bdz_ph_destroy(cmph_t *mphf)
free(mphf);
}
/** cmph_uint32 bdz_ph_search_fingerprint(cmph_t *mphf, const char *key, cmph_uint32 keylen, cmph_uint32 * fingerprint);
* \brief Computes the mphf value and a fingerprint of 12 bytes (i.e., figerprint should be a prealocated area to fit three 4-byte integers).
* \param mphf pointer to the resulting function
* \param key is the key to be hashed
* \param keylen is the key legth in bytes
* \return The mphf value
*
* Computes the mphf value and a fingerprint of 12 bytes. The figerprint pointer should be
* a prealocated area to fit three 4-byte integers. You don't need to use all the 12 bytes
* as fingerprint. According to the application, just few bits can be enough, once mphf does
* not allow collisions for the keys previously known.
*/
cmph_uint32 bdz_ph_search_fingerprint(cmph_t *mphf, const char *key, cmph_uint32 keylen, cmph_uint32 * fingerprint)
{
register bdz_ph_data_t *bdz_ph = mphf->data;
cmph_uint32 hl[3];
register cmph_uint8 byte0, byte1, byte2;
register cmph_uint32 vertex;
hash_vector(bdz_ph->hl, key, keylen,hl);
memcpy(fingerprint, hl, sizeof(hl));
hl[0] = hl[0] % bdz_ph->r;
hl[1] = hl[1] % bdz_ph->r + bdz_ph->r;
hl[2] = hl[2] % bdz_ph->r + (bdz_ph->r << 1);
byte0 = bdz_ph->g[hl[0]/5];
byte1 = bdz_ph->g[hl[1]/5];
byte2 = bdz_ph->g[hl[2]/5];
byte0 = lookup_table[hl[0]%5][byte0];
byte1 = lookup_table[hl[1]%5][byte1];
byte2 = lookup_table[hl[2]%5][byte2];
vertex = hl[(byte0 + byte1 + byte2)%3];
return vertex;
}
/** \fn void bdz_ph_pack(cmph_t *mphf, void *packed_mphf);
* \brief Support the ability to pack a perfect hash function into a preallocated contiguous memory space pointed by packed_mphf.
* \param mphf pointer to the resulting mphf