Added posix code

conts/posix/test0/src/clonetest.c

@@ -0,0 +1,59 @@
+/*
+ * Clone test.
+ */
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/mman.h>
+#include <sched.h>
+#include <errno.h>
+#include <tests.h>
+
+int clone_global = 0;
+
+extern pid_t parent_of_all;
+
+int my_thread_func(void *arg)
+{
+	for (int i = 0; i < 25; i++)
+		clone_global++;
+	_exit(0);
+}
+
+int clonetest(void)
+{
+	pid_t childid;
+	void *child_stack;
+
+	/* Parent loops and calls clone() to clone new threads. Children don't come back from the clone() call */
+	for (int i = 0; i < 4; i++) {
+		if ((child_stack = mmap(0, 0x1000, PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE | MAP_GROWSDOWN, 0, 0)) == MAP_FAILED) {
+			test_printf("MMAP failed.\n");
+			goto out_err;
+		} else {
+			test_printf("Mapped area starting at %p\n", child_stack);
+		}
+		((int *)child_stack)[-1] = 5; /* Test mapped area */
+
+		test_printf("Cloning...\n");
+
+		if ((childid = clone(my_thread_func, child_stack,
+		     CLONE_PARENT | CLONE_FS | CLONE_VM | CLONE_THREAD | CLONE_SIGHAND, 0)) < 0) {
+			test_printf("CLONE failed.\n");
+			goto out_err;
+		} else {
+			test_printf("Cloned a new thread with child pid %d\n", childid);
+		}
+	}
+
+	/* TODO: Add wait() or something similar and check that global is 100 */
+
+	if (getpid() == parent_of_all)
+		printf("CLONE TEST          -- PASSED --\n");
+
+	return 0;
+out_err:
+	printf("CLONE TEST          -- FAILED --\n");
+	return 0;
+}
+