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/* ISC license. */
#include <errno.h>
#include <skalibs/error.h>
#include <s6-dns/s6dns-domain.h>
#include <s6-dns/s6dns-message.h>
#include <s6-dns/s6dns-engine.h>
#include <s6-dns/s6dns-resolve.h>
int s6dns_resolveq_r (char const *name, size_t len, uint16_t qtype, s6dns_message_rr_func_t_ref parsefunc, void *data, s6dns_rci_t const *rci, s6dns_debughook_t const *dbh, tain_t const *deadline, tain_t *stamp)
{
s6dns_engine_t dtl[rci->rulesnum] ;
unsigned int best = 0 ;
unsigned int n ;
int e = 0 ;
unsigned int i = 0 ;
{
s6dns_domain_t domains[rci->rulesnum] ;
n = s6dns_domain_fromstring_qualify_encode(domains, name, len, rci->rules.s, rci->rulesnum) ;
if (!n) return -1 ;
for (; i < n ; i++)
{
dtl[i] = s6dns_engine_zero ;
if (!s6dns_engine_init_r(dtl + i, &rci->servers, S6DNS_O_RECURSIVE, domains[i].s, domains[i].len, qtype, dbh, deadline, stamp))
{
s6dns_engine_freen(dtl, i) ;
return -1 ;
}
}
}
/*
Wait until the "best" answer arrives, then scan until a positive answer
is found.
dtl[i].status == EAGAIN : query still pending
other nonzero dtl[i].status : error, give up
dtl[i].status == 0 : answer #i has arrived, in which case parse it;
r < 0 : error, give up
r > 0 : positive answer, return it
r == 0 : negative answer. If it's non-fatal (i.e. NXDOMAIN),
then move on to the next best FQDN.
*/
for (;;)
{
int k = s6dns_resolven_loop(dtl, n, 1, deadline, stamp) ;
if (k < 0) goto err ;
if ((unsigned int)k == best)
{
for (;; best++)
{
s6dns_message_header_t h ;
int r ;
if (best >= n) goto notfound ;
if (error_isagain(dtl[best].status)) break ;
if (dtl[best].status) { errno = dtl[best].status ; goto err ; }
r = s6dns_message_parse(&h, s6dns_engine_packet(dtl + best), s6dns_engine_packetlen(dtl + best), parsefunc, data) ;
if (r < 0) goto err ;
else if (r) goto found ;
else switch (errno)
{
case EBUSY :
case ENOENT :
case ECONNREFUSED :
case EIO :
break ;
default : goto err ;
}
if (!best) e = errno ;
}
}
}
found:
s6dns_engine_freen(dtl, n) ;
return 1 ;
notfound:
s6dns_engine_freen(dtl, n) ;
return (errno = e, 0) ;
err:
s6dns_engine_freen(dtl, n) ;
return -1 ;
}
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