Add test for internal threadpool and a new testing directory for internal APIs.

Author: insertinterestingnamehere

test/CMakeLists.txt

@@ -29,5 +29,6 @@ if (${QTHREADS_BUILD_TESTS})
 
   add_subdirectory(basics)
   add_subdirectory(features)
+  add_subdirectory(internal)
   add_subdirectory(stress)
 endif()

test/internal/CMakeLists.txt

@@ -0,0 +1,4 @@
+# tests for internal APIs can access internal headers.
+include_directories("../../include")
+
+qthreads_test(threadpool)

test/internal/threadpool.c

@@ -0,0 +1,18 @@
+#include "argparsing.h"
+#include "qt_threadpool.h"
+
+static int on_thread_test(void *arg) {
+  printf("hello from thread\n");
+  return 0;
+}
+
+int main() {
+  hw_pool_init(2);
+  hw_pool_destroy();
+  hw_pool_init(2);
+  hw_pool_run_on_all(&on_thread_test, NULL);
+  hw_pool_destroy();
+  printf("exited successfully\n");
+  fflush(stdout);
+  return 0;
+}