resolver: use explicit resolver item provided by caller

This avoids the need to perform multiple allocations for dialing,
eliminating additional potential failures.  Cancellation is also
made simpler and more perfectly robust.

4 files changed, 33 insertions, 7 deletions

diff --git a/src/core/platform.h b/src/core/platform.h
index 8b7aabbc..47f90467 100644
--- a/src/core/platform.h
+++ b/src/core/platform.h
@@ -347,6 +347,17 @@ extern int nni_tcp_listener_set(
 extern int nni_tcp_listener_get(
     nni_tcp_listener *, const char *, void *, size_t *, nni_type);
 
+typedef struct nni_resolv_item {
+	int           ri_family;
+	bool          ri_passive;
+	const char   *ri_host;
+	uint16_t      ri_port;
+	nng_sockaddr *ri_sa; // where result will be written
+
+} nni_resolv_item;
+
+extern void nni_resolv(nni_resolv_item *, nni_aio *);
+
 // nni_resolv_ip resolves a DNS host and service name asynchronously.
 // The family should be one of NNG_AF_INET, NNG_AF_INET6, or NNG_AF_UNSPEC.
 // The first two constrain the name to those families, while the third will
diff --git a/src/core/tcp.c b/src/core/tcp.c
index fd1c7e96..b0ed75fb 100644
--- a/src/core/tcp.c
+++ b/src/core/tcp.c
@@ -31,6 +31,7 @@ typedef struct {
 	nni_aio           conaio; // platform connection aio
 	nni_list          conaios;
 	nni_mtx           mtx;
+	nni_resolv_item   resolv;
 } tcp_dialer;
 
 static void
@@ -57,7 +58,14 @@ tcp_dial_start_next(tcp_dialer *d)
 	if (nni_list_empty(&d->conaios)) {
 		return;
 	}
-	nni_resolv_ip(d->host, d->port, d->af, false, &d->sa, &d->resaio);
+	memset(&d->resolv, 0, sizeof(d->resolv));
+	d->resolv.ri_family  = d->af;
+	d->resolv.ri_passive = false;
+	d->resolv.ri_host    = d->host;
+	d->resolv.ri_port    = d->port;
+	d->resolv.ri_sa      = &d->sa;
+
+	nni_resolv(&d->resolv, &d->resaio);
 }
 
 static void
diff --git a/src/core/thread.c b/src/core/thread.c
index 6f50476a..15baab04 100644
--- a/src/core/thread.c
+++ b/src/core/thread.c
@@ -172,4 +172,4 @@ void
 nni_thr_set_name(nni_thr *thr, const char *name)
 {
 	nni_plat_thr_set_name(thr != NULL ? &thr->thr : NULL, name);
-}
\ No newline at end of file
+}
diff --git a/src/core/url.c b/src/core/url.c
index 1b39f809..48c79037 100644
--- a/src/core/url.c
+++ b/src/core/url.c
@@ -678,10 +678,11 @@ nng_url_clone(nng_url **dstp, const nng_url *src)
 int
 nni_url_to_address(nng_sockaddr *sa, const nng_url *url)
 {
-	int         af;
-	nni_aio     aio;
-	const char *h;
-	int         rv;
+	int             af;
+	nni_aio         aio;
+	const char     *h;
+	int             rv;
+	nni_resolv_item ri;
 
 	// This assumes the scheme is one that uses TCP/IP addresses.
 
@@ -700,7 +701,13 @@ nni_url_to_address(nng_sockaddr *sa, const nng_url *url)
 		h = NULL;
 	}
 
-	nni_resolv_ip(h, url->u_port, af, true, sa, &aio);
+	memset(&ri, 0, sizeof(ri));
+	ri.ri_family  = af;
+	ri.ri_passive = true;
+	ri.ri_host    = h;
+	ri.ri_port    = url->u_port;
+	ri.ri_sa      = sa;
+	nni_resolv(&ri, &aio);
 	nni_aio_wait(&aio);
 	rv = nni_aio_result(&aio);
 	nni_aio_fini(&aio);