fixes #2 Websocket transport

This is a rather large changeset -- it fundamentally adds websocket
transport, but as part of this changeset we added a generic framework
for both HTTP and websocket.  We also made some supporting changes to
the core, such as changing the way timeouts work for AIOs and adding
additional state keeping for AIOs, and adding a common framework for
deferred finalization (to avoid certain kinds of circular deadlocks
during resource cleanup).  We also invented a new initialization framework
so that we can avoid wiring in knowledge about them into the master
initialization framework.

The HTTP framework is not yet complete, but it is good enough for simple
static serving and building additional services on top of -- including
websocket.  We expect both websocket and HTTP support to evolve
considerably, and so these are not part of the public API yet.

Property support for the websocket transport (in particular address
properties) is still missing, as is support for TLS.

The websocket transport here is a bit more robust than the original
nanomsg implementation, as it supports multiple sockets listening at
the same port sharing the same HTTP server instance, discriminating
between them based on URI (and possibly the virtual host).

Websocket is enabled by default at present, and work to conditionalize
HTTP and websocket further (to minimize bloat) is still pending.

1 files changed, 71 insertions, 1 deletions

diff --git a/src/core/transport.c b/src/core/transport.c
index 359b03fd..31da773f 100644
--- a/src/core/transport.c
+++ b/src/core/transport.c
@@ -13,6 +13,7 @@
 #include "transport/ipc/ipc.h"
 #include "transport/tcp/tcp.h"
 #include "transport/tls/tls.h"
+#include "transport/ws/websocket.h"
 #include "transport/zerotier/zerotier.h"
 
 #include <stdio.h>
@@ -105,6 +106,72 @@ nni_tran_find(const char *addr)
 	return (NULL);
 }
 
+// nni_tran_parse_host_port is a convenience routine to parse the host portion
+// of a URL (which includes a DNS name or IP address and an optional service
+// name or port, separated by a colon) into its host and port name parts.  It
+// understands IPv6 address literals when surrounded by brackets ([]).
+// If either component is empty, then NULL is passed back for the value,
+// otherwise a string suitable for freeing with nni_strfree is supplied.
+int
+nni_tran_parse_host_port(const char *pair, char **hostp, char **portp)
+{
+	const char *hstart;
+	const char *pstart;
+	char *      host;
+	char *      port;
+	size_t      hlen, plen;
+
+	if (pair[0] == '[') {
+		hstart = pair + 1;
+		hlen   = 0;
+		while (hstart[hlen] != ']') {
+			if (hstart[hlen] == '\0') {
+				return (NNG_EADDRINVAL);
+			}
+			hlen++;
+		}
+		pstart = hstart + hlen + 1; // skip over the trailing ']'
+	} else {
+		// Normal thing.
+		hstart = pair;
+		hlen   = 0;
+		while ((hstart[hlen] != ':') && (hstart[hlen] != '\0')) {
+			hlen++;
+		}
+		pstart = hstart + hlen;
+	}
+	if (pstart[0] == ':') {
+		pstart++;
+	}
+	plen = strlen(pstart);
+
+	host = NULL;
+	if (hostp) {
+		if ((hlen > 1) || ((hlen == 1) && (*hstart != '*'))) {
+			if ((host = nni_alloc(hlen + 1)) == NULL) {
+				return (NNG_ENOMEM);
+			}
+			memcpy(host, hstart, hlen);
+			host[hlen] = '\0';
+		}
+	}
+
+	port = NULL;
+	if ((plen != 0) && (portp)) {
+		if ((port = nni_strdup(pstart)) == NULL) {
+			nni_strfree(host);
+			return (NNG_ENOMEM);
+		}
+	}
+	if (hostp) {
+		*hostp = host;
+	}
+	if (portp) {
+		*portp = port;
+	}
+	return (0);
+}
+
 int
 nni_tran_chkopt(const char *name, const void *v, size_t sz)
 {
@@ -154,9 +221,12 @@ static nni_tran_ctor nni_tran_ctors[] = {
 #ifdef NNG_HAVE_TLS
 	nng_tls_register,
 #endif
-#ifdef NNI_HAVE_ZEROTIER
+#ifdef NNG_HAVE_ZEROTIER
 	nng_zt_register,
 #endif
+#ifdef NNG_HAVE_WEBSOCKET
+	nng_ws_register,
+#endif
 	NULL,
 };