fixes #143 Protocols and transports should be "configurable"

This makes all the protocols and transports optional.  All
of them except ZeroTier are enabled by default, but you can
now disable them (remove from the build) with cmake options.

The test suite is modified so that tests still run as much
as they can, but skip over things caused by missing functionality
from the library (due to configuration).

Further, the constant definitions and prototypes for functions
that are specific to transports or protocols are moved into
appropriate headers, which should be included directly by
applications wishing to use these.

We have also added and improved documentation -- all of the
transports are documented, and several more man pages for
protocols have been added.  (Req/Rep and Surveyor are still
missing.)

1 files changed, 47 insertions, 0 deletions

diff --git a/tests/stubs.h b/tests/stubs.h
index 780ac772..0641c970 100644
--- a/tests/stubs.h
+++ b/tests/stubs.h
@@ -44,4 +44,51 @@ getms(void)
 #endif
 }
 
+int
+nosocket(nng_socket *s)
+{
+	ConveySkip("Protocol unconfigured");
+	return (NNG_ENOTSUP);
+}
+
+#ifndef NNG_HAVE_REQ0
+#define nng_req0_open nosocket
+#endif
+
+#ifndef NNG_HAVE_REP0
+#define nng_rep0_open nosocket
+#endif
+
+#ifndef NNG_HAVE_PUB0
+#define nng_pub0_open nosocket
+#endif
+
+#ifndef NNG_HAVE_SUB0
+#define nng_sub0_open nosocket
+#endif
+
+#ifndef NNG_HAVE_PAIR0
+#define nng_pair0_open nosocket
+#endif
+
+#ifndef NNG_HAVE_PAIR1
+#define nng_pair1_open nosocket
+#endif
+
+#ifndef NNG_HAVE_PUSH0
+#define nng_push0_open nosocket
+#endif
+
+#ifndef NNG_HAVE_PULL0
+#define nng_pull0_open nosocket
+#endif
+
+#ifndef NNG_HAVE_SURVEYOR0
+#define nng_surveyor0_open nosocket
+#endif
+
+#ifndef NNG_HAVE_RESPONDENT0
+#define nng_respondent0_open nosocket
+#endif
+
 #endif // STUBS_H