diff --git a/libmapper/internal.h b/libmapper/internal.h
new file mode 100644
index 0000000..e6f9a07
--- /dev/null
+++ b/libmapper/internal.h
@@ -0,0 +1,10 @@
+#pragma once
+#ifdef __cplusplus
+extern "C" {
+#endif
+int sarraylen(char* array[]);
+void sarrayfree(char* array[]);
+char** sarraydup(char* array[]);
+#ifdef __cplusplus
+}
+#endif
diff --git a/libmapper/mapper.c b/libmapper/mapper.c
index fb07940..4a1cd3b 100644
--- a/libmapper/mapper.c
+++ b/libmapper/mapper.c
@@ -27,6 +27,8 @@
 #include <systemd/sd-event.h>
 #include <unistd.h>
 
+#include "internal.h"
+
 #define _public_ __attribute__((__visibility__("default")))
 
 static const char* async_wait_introspection_match =
@@ -99,7 +101,7 @@
 static int async_subtree_getpaths_callback(sd_bus_message*, void*,
                                            sd_bus_error*);
 
-static int sarraylen(char* array[])
+int sarraylen(char* array[])
 {
     int count = 0;
     char** p = array;
@@ -113,7 +115,7 @@
     return count;
 }
 
-static void sarrayfree(char* array[])
+void sarrayfree(char* array[])
 {
     char** p = array;
     while (*p != NULL)
@@ -124,13 +126,13 @@
     free(array);
 }
 
-static char** sarraydup(char* array[])
+char** sarraydup(char* array[])
 {
     int count = sarraylen(array);
     int i;
     char** ret = NULL;
 
-    ret = malloc(sizeof(*ret) * count);
+    ret = calloc(count + 1, sizeof(*ret));
     if (!ret)
         return NULL;
 
diff --git a/libmapper/test/Makefile.am.include b/libmapper/test/Makefile.am.include
new file mode 100644
index 0000000..fdd4849
--- /dev/null
+++ b/libmapper/test/Makefile.am.include
@@ -0,0 +1,5 @@
+libmapper_test_mapper_SOURCES = %reldir%/mapper.cpp \
+		libmapper/mapper.c libmapper/test/utils.c
+
+check_PROGRAMS += \
+	%reldir%/mapper
diff --git a/libmapper/test/mapper.cpp b/libmapper/test/mapper.cpp
new file mode 100644
index 0000000..8831b62
--- /dev/null
+++ b/libmapper/test/mapper.cpp
@@ -0,0 +1,22 @@
+#include "../internal.h"
+#include "utils.h"
+
+#include <gtest/gtest.h>
+
+TEST(TestSarray, Dup)
+{
+    auto a = generate_test_sarray(3);
+
+    auto size = sarraylen(a);
+    EXPECT_EQ(size, 3);
+
+    auto b = sarraydup(a);
+    size_t i;
+
+    for (i = 0; i < 4; i++)
+    {
+        EXPECT_STREQ(a[i], b[i]);
+    }
+    sarrayfree(a);
+    sarrayfree(b);
+}
diff --git a/libmapper/test/utils.c b/libmapper/test/utils.c
new file mode 100644
index 0000000..b3c7ae1
--- /dev/null
+++ b/libmapper/test/utils.c
@@ -0,0 +1,31 @@
+#include "utils.h"
+
+#include <stdlib.h>
+#include <string.h>
+
+char** generate_test_sarray(size_t len)
+{
+    static const char testString[] = "test";
+    size_t i;
+    char** ret = calloc(len + 1, sizeof(*ret));
+    if (!ret)
+        return NULL;
+
+    for (i = 0; i < len; ++i)
+    {
+        ret[i] = strdup(testString);
+        if (!ret[i])
+            goto error;
+    }
+
+    return ret;
+
+error:
+    for (i = 0; i < len; ++i)
+    {
+        free(ret[i]);
+    }
+    free(ret);
+
+    return NULL;
+}
diff --git a/libmapper/test/utils.h b/libmapper/test/utils.h
new file mode 100644
index 0000000..73162cb
--- /dev/null
+++ b/libmapper/test/utils.h
@@ -0,0 +1,9 @@
+#pragma once
+#include <stddef.h>
+#ifdef __cplusplus
+extern "C" {
+#endif
+char** generate_test_sarray(size_t);
+#ifdef __cplusplus
+}
+#endif