Initial commit

1 files changed, 89 insertions, 0 deletions

diff --git a/src/libs6dns/s6dns_resolveq.c b/src/libs6dns/s6dns_resolveq.c
new file mode 100644
index 0000000..c43db1f
--- /dev/null
+++ b/src/libs6dns/s6dns_resolveq.c
@@ -0,0 +1,89 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/uint16.h>
+#include <skalibs/error.h>
+#include <skalibs/tai.h>
+#include <s6-dns/s6dns-domain.h>
+#include <s6-dns/s6dns-message.h>
+#include <s6-dns/s6dns-engine.h>
+#include <s6-dns/s6dns-rci.h>
+#include <s6-dns/s6dns-resolve.h>
+
+int s6dns_resolveq_r (char const *name, unsigned int len, uint16 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 ;
+  register 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 (;;)
+  {
+    register 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 ;
+        register 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 ;
+}