make sure dlsym() properly returns NULL with undefined symbols

1 files changed, 29 insertions, 0 deletions

diff --git a/test/dlopen/dlundef.c b/test/dlopen/dlundef.c
new file mode 100644
index 000000000..cefd93318
--- /dev/null
+++ b/test/dlopen/dlundef.c
@@ -0,0 +1,29 @@
+#include <fcntl.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <dlfcn.h>
+#include <stdint.h>
+
+#define LIBNAME "libundef.so"
+
+int main(int argc, char **argv)
+{
+	void *handle;
+	int (*myundefined)(void);
+
+	handle = dlopen(LIBNAME, RTLD_LAZY);
+	if (!handle) {
+		fprintf(stderr, "Could not open ./%s: %s\n", LIBNAME, dlerror());
+		return EXIT_FAILURE;
+	}
+
+	myundefined = dlsym(handle, "__booga_booga_you_cant_touch_this__");
+	if (myundefined != NULL) {
+		fprintf(stderr, "dlsym() found a symbol that does not exist!\n");
+		return EXIT_FAILURE;
+	}
+
+	dlclose(handle);
+
+	return EXIT_SUCCESS;
+}