static foreign_t
pl_sha_new_ctx(term_t ctx, term_t options)
{ struct context c;
optval *op = &(c.opts);
if ( !sha_options(options, op) )
return FALSE;
c.magic = CONTEXT_MAGIC;
if ( op->algorithm == ALGORITHM_SHA1 )
{ sha1_begin(&(c.context.sha1));
} else
{ sha2_begin((unsigned long) op->digest_size, &(c.context.sha2));
}
/* NB: the context size depends on the digest size */
/* (e. g., sha512_ctx is twice as long as sha256_ctx) */
/* so there're extra data. It will do no harm, though. */
/* . */
return PL_unify_string_nchars(ctx, sizeof(c), (char*)&c);
}
std::string vmsHash::Hash_SHA2(LPCSTR pszFile)
{
sha2_ctx sha2;
vmsFile file;
__int64 trb = 0;
BYTE abBuf [16000];
sha2_begin (m_nSHA2Strength, &sha2);
try {
file.Open (pszFile, TRUE);
__int64 uSize = file.get_Size ();
DWORD dwRead;
while (dwRead = file.Read (abBuf, sizeof (abBuf)))
{
sha2_hash (abBuf, dwRead, &sha2);
trb += dwRead;
if (m_pEvents)
{
double f = (double)trb / uSize * 100;
if (false == m_pEvents->OnProgressChanged (f)) {
trb = 0;
break;
}
}
}
BYTE abRes [256];
sha2_end (abRes, &sha2);
if (trb == 0 && uSize != 0)
return "";
return Hash_ResultToStr (abRes, m_nSHA2Strength / 8);
}catch (...) {return "";}
}
