fixes #254 nngcat should have a --version option

We only add a basic --version (also -V). I'm still trying to figure
out how to convince cmake to emit its compilation flags into a file
where we can use them for output.

2 files changed, 16 insertions, 3 deletions

diff --git a/src/nng.c b/src/nng.c
index b7255904..19b33220 100644
--- a/src/nng.c
+++ b/src/nng.c
@@ -8,6 +8,7 @@
 // found online at https://opensource.org/licenses/MIT.
 //
 
+#include "nng.h"
 #include "core/nng_impl.h"
 
 // This file provides the "public" API.  This is a thin wrapper around
@@ -1212,3 +1213,13 @@ nng_url_clone(nng_url **dstp, const nng_url *src)
 {
 	return (nni_url_clone(dstp, src));
 }
+
+#define xstr(a) str(a)
+#define str(a) #a
+
+const char *
+nng_version(void)
+{
+	return (xstr(NNG_MAJOR_VERSION) "." xstr(NNG_MINOR_VERSION) "." xstr(
+	    NNG_PATCH_VERSION));
+}
diff --git a/src/nng.h b/src/nng.h
index e2cdb8fa..7615785d 100644
--- a/src/nng.h
+++ b/src/nng.h
@@ -47,9 +47,9 @@ extern "C" {
 // may not necessarily match the ABI versions. Right now at
 // version 0, you should not be making any forward compatibility
 // assumptions.
-#define	NNG_MAJOR_VERSION	0
-#define	NNG_MINOR_VERSION	5
-#define	NNG_PATCH_VERSION	0
+#define NNG_MAJOR_VERSION 0
+#define NNG_MINOR_VERSION 5
+#define NNG_PATCH_VERSION 0
 
 // Types common to nng.
 typedef uint32_t            nng_socket;
@@ -698,6 +698,8 @@ NNG_DECL void nng_url_free(nng_url *);
 // nng_url_clone clones a URL structure.
 NNG_DECL int nng_url_clone(nng_url **, const nng_url *);
 
+// nng_version returns the library version as a human readable string.
+NNG_DECL const char *nng_version(void);
 #ifdef __cplusplus
 }
 #endif