fixes #166 Websocket TLS mapping

This introduces the wss:// scheme, which is available and works like
the ws:// scheme if TLS is enabled in the library.

The library modularization is refactored somewhat, to make it easier
to use.  There is now a single NNG_ENABLE_TLS that enables TLS support
under the hood.

This also adds a new option for the TLS transport, NNG_OPT_TLS_CONFIG
(and a similar one for WSS, NNG_OPT_TLS_WSS_CONFIG) that offer access
to the underlying TLS configuration object, which now has a public API
to go with it as well.

Note that it is also possible to use pure HTTPS using the *private*
API, which will be exposed in a public form soon.

3 files changed, 34 insertions, 13 deletions

diff --git a/src/core/options.c b/src/core/options.c
index 1417d0b3..ef7420d6 100644
--- a/src/core/options.c
+++ b/src/core/options.c
@@ -187,6 +187,19 @@ nni_getopt_size(size_t u, void *val, size_t *sizep)
 }
 
 int
+nni_getopt_ptr(void *ptr, void *val, size_t *sizep)
+{
+	size_t sz = sizeof(ptr);
+
+	if (sz > *sizep) {
+		sz = *sizep;
+	}
+	*sizep = sizeof(ptr);
+	memcpy(val, &ptr, sz);
+	return (0);
+}
+
+int
 nni_setopt_buf(nni_msgq *mq, const void *val, size_t sz)
 {
 	int len;
diff --git a/src/core/options.h b/src/core/options.h
index d373851f..e9aa16dd 100644
--- a/src/core/options.h
+++ b/src/core/options.h
@@ -58,6 +58,9 @@ extern int nni_setopt_size(size_t *, const void *, size_t, size_t, size_t);
 // nni_getopt_size obtains a size_t option.
 extern int nni_getopt_size(size_t, void *, size_t *);
 
+// nni_getopt_ptr obtains a pointer option.
+extern int nni_getopt_ptr(void *, void *, size_t *);
+
 extern int nni_chkopt_ms(const void *, size_t);
 extern int nni_chkopt_int(const void *, size_t, int, int);
 extern int nni_chkopt_size(const void *, size_t, size_t, size_t);
diff --git a/src/core/transport.c b/src/core/transport.c
index 31da773f..9c129a72 100644
--- a/src/core/transport.c
+++ b/src/core/transport.c
@@ -56,12 +56,12 @@ nni_tran_register(const nni_tran *tran)
 	nni_mtx_lock(&nni_tran_lk);
 	// Check to see if the transport is already registered...
 	NNI_LIST_FOREACH (&nni_tran_list, t) {
-		if (tran->tran_init == t->t_tran.tran_init) {
-			nni_mtx_unlock(&nni_tran_lk);
-			// Same transport, duplicate registration.
-			return (0);
-		}
 		if (strcmp(tran->tran_scheme, t->t_tran.tran_scheme) == 0) {
+			if (tran->tran_init == t->t_tran.tran_init) {
+				// duplicate.
+				nni_mtx_unlock(&nni_tran_lk);
+				return (0);
+			}
 			nni_mtx_unlock(&nni_tran_lk);
 			return (NNG_ESTATE);
 		}
@@ -208,25 +208,30 @@ nni_tran_chkopt(const char *name, const void *v, size_t sz)
 
 typedef int (*nni_tran_ctor)(void);
 
+// These are just the statically compiled in constructors.
+// In the future we might want to support dynamic additions.
 static nni_tran_ctor nni_tran_ctors[] = {
-#ifdef NNG_HAVE_INPROC
+#ifdef NNG_TRANSPORT_INPROC
 	nng_inproc_register,
 #endif
-#ifdef NNG_HAVE_IPC
+#ifdef NNG_TRANSPORT_IPC
 	nng_ipc_register,
 #endif
-#ifdef NNG_HAVE_TCP
+#ifdef NNG_TRANSPORT_TCP
 	nng_tcp_register,
 #endif
-#ifdef NNG_HAVE_TLS
+#ifdef NNG_TRANSPORT_TLS
 	nng_tls_register,
 #endif
-#ifdef NNG_HAVE_ZEROTIER
-	nng_zt_register,
-#endif
-#ifdef NNG_HAVE_WEBSOCKET
+#ifdef NNG_TRANSPORT_WS
 	nng_ws_register,
 #endif
+#ifdef NNG_TRANSPORT_WSS
+	nng_wss_register,
+#endif
+#ifdef NNG_TRANSPORT_ZEROTIER
+	nng_zt_register,
+#endif
 	NULL,
 };