test: fix filter-build test and bugs

The tests for checking the filter build recompile and are successfull.

Changes:
  - spotted a couple of bugs for adding the arguments in the filter
  - readded function `filter_flush_args` to flush_args; this is needed
    to distinguish when the arguments belong to the same block or are different
    entries to the same syscall
  - build the filter in a way that CMP_EQ corresponds to BPF_JEQ and we
    don't need to awkwardly negate the operations (still TODO for AND_EQ)

1 files changed, 2 insertions, 2 deletions

diff --git a/tests/unit/testutil.h b/tests/unit/testutil.h
index a0fa0b8..caccd44 100644
--- a/tests/unit/testutil.h
+++ b/tests/unit/testutil.h
@@ -58,7 +58,7 @@ static inline void *test_gluten_write_ptr(struct gluten *g,
 		ck_assert_ptr_nonnull(p);                        \
 		memcpy(&ref, p, sizeof(ref));                    \
 	} while (0)
-
+#define NS_NUM CONTEXT_TYPE_MAX - 3
 struct args_target {
         long ret;
         int err;
@@ -67,7 +67,7 @@ struct args_target {
         int fd;
         int nr;
 	bool filter_args[6];
-	struct bpf_arg args[6];
+	struct bpf_field bpf_fields[6];
 	void *targs[6];
 	void *tclone;
 	bool ns[NS_NUM];