Implement retransmit and timeouts.

vstakhov · Feb 9, 2014 · b00d740 · b00d740
1 parent 6c47a29
commit b00d740
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Showing 2 changed files with 59 additions and 2 deletions.
diff --git a/src/dns.c b/src/dns.c
@@ -278,7 +278,7 @@ rdns_add_edns0 (struct rdns_request *req)
 }
 
 static int
-dns_send_request (struct rdns_request *req, int fd, bool new_req)
+rdns_send_request (struct rdns_request *req, int fd, bool new_req)
 {
  int r;
  struct rdns_server *serv = req->io->srv;
@@ -335,6 +335,12 @@ dns_send_request (struct rdns_request *req, int fd, bool new_req)
  return 1;
 }
 
+static void
+rdns_request_free (struct rdns_request *req)
+{
+ /* TODO: implement it */
+}
+
 static uint8_t *
 decompress_label (uint8_t *begin, uint16_t *len, uint16_t max)
 {
@@ -763,11 +769,61 @@ rdns_process_read (int fd, void *arg)
 void
 rdns_process_timer (void *arg)
 {
+ struct rdns_request *req = (struct rdns_request *)arg;
+ struct rdns_resolver *resolver;
+ int r;
+
+ resolver = req->resolver;
+
+ req->retransmits ++;
+ if (req->retransmits > resolver->max_retransmits) {
+ /* XXX: call the callback */
+ rdns_request_free (req);
+ return;
+ }
+ if (r == 0) {
+ /* Retransmit one more time */
+ resolver->async.del_timer (resolver->async.data,
+ req->async_event);
+ req->async_event = resolver->async.add_write (resolver->async.data,
+ req);
+ }
+ else if (r == -1) {
+ /* XXX: call the callback */
+ rdns_request_free (req);
+ }
+ else {
+ resolver->async.repeat_timer (resolver->async.data, req->async_event);
+ }
 }
 
 void
 rdns_process_retransmit (int fd, void *arg)
 {
+ struct rdns_request *req = (struct rdns_request *)arg;
+ struct rdns_resolver *resolver;
+ int r;
+
+ resolver = req->resolver;
+
+ resolver->async.del_write (resolver->async.data,
+ req->async_event);
+
+ r = rdns_send_request (req, fd, false);
+
+ if (r == 0) {
+ /* Retransmit one more time */
+ req->async_event = resolver->async.add_write (resolver->async.data,
+ req);
+ }
+ else if (r == -1) {
+ /* XXX: call the callback */
+ rdns_request_free (req);
+ }
+ else {
+ req->async_event = resolver->async.add_timer (resolver->async.data,
+ req->timeout, req);
+ }
 }
 
 bool rdns_make_request_full (
@@ -853,7 +909,7 @@ bool rdns_make_request_full (
  serv->cur_io_channel = serv->cur_io_channel->next;
 
  /* Now send request to server */
- r = dns_send_request (req, req->io->sock, true);
+ r = rdns_send_request (req, req->io->sock, true);
 
  if (r == -1) {
  return false;

diff --git a/src/dns_private.h b/src/dns_private.h
@@ -109,6 +109,7 @@ struct rdns_io_channel {
 struct rdns_resolver {
  struct rdns_server *servers;
  unsigned int request_timeout;
+ unsigned int max_retransmits;
  struct rdns_io_channel *io_channels; /**< hash of io chains indexed by socket */
  struct {
  void *data;