fixes #422 nng_aio_fini_cb() could go away

3 files changed, 10 insertions, 27 deletions

diff --git a/src/core/aio.c b/src/core/aio.c
index 388e6677..3606aa14 100644
--- a/src/core/aio.c
+++ b/src/core/aio.c
@@ -175,13 +175,6 @@ nni_aio_set_iov(nni_aio *aio, unsigned niov, const nni_iov *iov)
 	return (0);
 }
 
-void
-nni_aio_fini_cb(nni_aio *aio)
-{
-	nni_cv_fini(&aio->a_cv);
-	NNI_FREE_STRUCT(aio);
-}
-
 // nni_aio_stop cancels any oustanding operation, and waits for the
 // callback to complete, if still running.  It also marks the AIO as
 // stopped, preventing further calls to nni_aio_begin from succeeding.
diff --git a/src/core/aio.h b/src/core/aio.h
index d23ddf5b..9b7ac46f 100644
--- a/src/core/aio.h
+++ b/src/core/aio.h
@@ -32,12 +32,6 @@ extern int nni_aio_init(nni_aio **, nni_cb, void *);
 // on zero'd memory.
 extern void nni_aio_fini(nni_aio *);
 
-// nni_aio_fini_cb finalizes the aio WITHOUT waiting for it to complete.
-// This is intended exclusively for finalizing an AIO from a completion
-// callack for that AIO. It is important that the caller ensure that nothing
-// else might be waiting for that AIO or using it.
-extern void nni_aio_fini_cb(nni_aio *);
-
 // nni_aio_stop cancels any unfinished I/O, running completion callbacks,
 // but also prevents any new operations from starting (nni_aio_start will
 // return NNG_ESTATE).  This should be called before nni_aio_fini().  The
diff --git a/src/transport/zerotier/zerotier.c b/src/transport/zerotier/zerotier.c
index 73cddf7d..54e402be 100644
--- a/src/transport/zerotier/zerotier.c
+++ b/src/transport/zerotier/zerotier.c
@@ -1285,19 +1285,6 @@ typedef struct zt_send_hdr {
 	size_t       len;
 } zt_send_hdr;
 
-static void
-zt_wire_packet_send_cb(void *arg)
-{
-	// We don't actually care much about the results, we
-	// just need to release the resources.
-	nni_aio *    aio = arg;
-	zt_send_hdr *hdr;
-
-	hdr = nni_aio_get_data(aio, 0);
-	nni_free(hdr, hdr->len + sizeof(*hdr));
-	nni_aio_fini_cb(aio);
-}
-
 // This function is called when ZeroTier desires to send a
 // physical frame. The data is a UDP payload, the rest of the
 // payload should be set over vanilla UDP.
@@ -1345,7 +1332,7 @@ zt_wire_packet_send(ZT_Node *node, void *userptr, void *thr, int64_t socket,
 		return (-1);
 	}
 
-	if (nni_aio_init(&aio, zt_wire_packet_send_cb, NULL) != 0) {
+	if (nni_aio_init(&aio, NULL, NULL) != 0) {
 		// Out of memory
 		return (-1);
 	}
@@ -1371,6 +1358,15 @@ zt_wire_packet_send(ZT_Node *node, void *userptr, void *thr, int64_t socket,
 	// not great that we're holding the lock, also not tragic.
 	nni_plat_udp_send(udp, aio);
 
+	// UDP sending is "fast" on all platforms -- given that its
+	// best effort only, this will complete immediately, resulting
+	// in either a message on the wire, or a discarded frame.  We don't
+	// care which.  (There may be a few thread context switches, but
+	// none of them are going to have to wait for some unbounded time.)
+	nni_aio_wait(aio);
+	nni_aio_fini(aio);
+	nni_free(hdr, hdr->len + sizeof(*hdr));
+
 	return (0);
 }