Expose a library finalizer suitable for atexit().

3 files changed, 31 insertions, 9 deletions

diff --git a/src/nng.c b/src/nng.c
index 81e21ea2..59c003a7 100644
--- a/src/nng.c
+++ b/src/nng.c
@@ -37,6 +37,13 @@ nng_open(nng_socket *sidp, uint16_t proto)
 }
 
 
+void
+nng_fini(void)
+{
+	nni_fini();
+}
+
+
 int
 nng_shutdown(nng_socket sid)
 {
diff --git a/src/nng.h b/src/nng.h
index 5c1a2322..875bf995 100644
--- a/src/nng.h
+++ b/src/nng.h
@@ -55,6 +55,16 @@ typedef struct nng_stat		nng_stat;
 // mode.
 NNG_DECL int nng_open(nng_socket *, uint16_t proto);
 
+// nng_fini is used to terminate the library, freeing certain global resources.
+// Its a good idea to call this with atexit() or during application shutdown.
+// For most cases, this call is optional, but failure to do so may cause
+// memory checkers like valgrind to incorrectly flag memory leaks.  Note that
+// this particular API is NOT THREADSAFE, and MUST NOT BE CALLED WHILE ANY
+// OTHER APIS ARE IN USE.  (It is safe however to call other functions such
+// as nng_open *after* this function returns, provided that the functions do
+// not run concurrently!)
+NNG_DECL void nng_fini(void);
+
 // nng_close closes the socket, terminating all activity and
 // closing any underlying connections and releasing any associated
 // resources. Memory associated with the socket is freed, so it is an
diff --git a/src/platform/posix/posix_thread.c b/src/platform/posix/posix_thread.c
index 72e1bcaf..0d57e7ef 100644
--- a/src/platform/posix/posix_thread.c
+++ b/src/platform/posix/posix_thread.c
@@ -227,46 +227,50 @@ int
 nni_plat_init(int (*helper)(void))
 {
 	int rv;
+	int devnull;
 
 	if (nni_plat_forked) {
-		nni_panic("nng is fork-reentrant safe");
+		nni_panic("nng is not fork-reentrant safe");
 	}
 	if (nni_plat_inited) {
 		return (0);     // fast path
 	}
-
-	if ((nni_plat_devnull = open("/dev/null", O_RDONLY)) < 0) {
+	if ((devnull = open("/dev/null", O_RDONLY)) < 0) {
 		return (nni_plat_errno(errno));
 	}
+
 	pthread_mutex_lock(&nni_plat_lock);
 	if (nni_plat_inited) {        // check again under the lock to be sure
 		pthread_mutex_unlock(&nni_plat_lock);
-		(void) close(nni_plat_devnull);
+		close(devnull);
 		return (0);
 	}
 	if (pthread_condattr_init(&nni_cvattr) != 0) {
 		pthread_mutex_unlock(&nni_plat_lock);
-		(void) close(nni_plat_devnull);
+		(void) close(devnull);
 		return (NNG_ENOMEM);
 	}
 #if !defined(NNG_USE_GETTIMEOFDAY) && NNG_USE_CLOCKID != CLOCK_REALTIME
 	if (pthread_condattr_setclock(&nni_cvattr, NNG_USE_CLOCKID) != 0) {
 		pthread_mutex_unlock(&nni_plat_lock);
-		(void) close(nni_plat_devnull);
+		(void) close(devnull);
 		return (NNG_ENOMEM);
 	}
 #endif
 
 	if (pthread_mutexattr_init(&nni_mxattr) != 0) {
 		pthread_mutex_unlock(&nni_plat_lock);
-		(void) close(nni_plat_devnull);
+		pthread_condattr_destroy(&nni_cvattr);
+		(void) close(devnull);
 		return (NNG_ENOMEM);
 	}
 
 	rv = pthread_mutexattr_settype(&nni_mxattr, PTHREAD_MUTEX_ERRORCHECK);
 	if (rv != 0) {
 		pthread_mutex_unlock(&nni_plat_lock);
-		(void) close(nni_plat_devnull);
+		(void) close(devnull);
+		pthread_mutexattr_destroy(&nni_mxattr);
+		pthread_condattr_destroy(&nni_cvattr);
 		return (NNG_ENOMEM);
 	}
 
@@ -287,7 +291,7 @@ nni_plat_init(int (*helper)(void))
 
 	if (pthread_atfork(NULL, NULL, nni_atfork_child) != 0) {
 		pthread_mutex_unlock(&nni_plat_lock);
-		(void) close(nni_plat_devnull);
+		(void) close(devnull);
 		pthread_mutexattr_destroy(&nni_mxattr);
 		pthread_condattr_destroy(&nni_cvattr);
 		pthread_attr_destroy(&nni_pthread_attr);
@@ -296,6 +300,7 @@ nni_plat_init(int (*helper)(void))
 	if ((rv = helper()) == 0) {
 		nni_plat_inited = 1;
 	}
+	nni_plat_devnull = devnull;
 	pthread_mutex_unlock(&nni_plat_lock);
 
 	return (rv);