tests: add chroot.test

* tests/chroot.c: New file.
* tests/chroot.test: New test.
* tests/.gitignore: Add chroot.
* tests/Makefile.am (check_PROGRAMS): Likewise.
(DECODER_TESTS): Add chroot.test.
diff --git a/tests/chroot.c b/tests/chroot.c
new file mode 100644
index 0000000..fb12a31
--- /dev/null
+++ b/tests/chroot.c
@@ -0,0 +1,37 @@
+#include "tests.h"
+#include <sys/syscall.h>
+
+#ifdef __NR_chroot
+
+# include <errno.h>
+# include <stdio.h>
+# include <unistd.h>
+
+int
+main(void)
+{
+	static const char sample[] = "chroot.sample";
+	int rc = syscall(__NR_chroot ,sample);
+	const char *errno_text;
+	switch (errno) {
+		case ENOSYS:
+			errno_text = "ENOSYS";
+			break;
+		case EPERM:
+			errno_text = "EPERM";
+			break;
+		default:
+			errno_text = "ENOENT";
+	}
+	printf("chroot(\"%s\") = %d %s (%m)\n",
+	       sample, rc, errno_text);
+
+	puts("+++ exited with 0 +++");
+	return 0;
+}
+
+#else
+
+SKIP_MAIN_UNDEFINED("__NR_chroot")
+
+#endif