// SPDX-License-Identifier: GPL-2.0

#include <linux/bpf.h>

#include <bpf/bpf_helpers.h>

struct S {
        int v;
};

struct S global_variable = {};

struct {
        __uint(type, BPF_MAP_TYPE_ARRAY);
        __uint(max_entries, 7);
        __type(key, __u32);
        __type(value, int);
} values SEC(".maps");

static void save_value(__u32 index, int value)
{
        bpf_map_update_elem(&values, &index, &value, 0);
}

__noinline int foo(__u32 index, struct S *s)
{
        if (s) {
                save_value(index, s->v);
                return ++s->v;
        }

        save_value(index, 0);

        return 1;
}

__noinline int bar(__u32 index, volatile struct S *s)
{
        if (s) {
                save_value(index, s->v);
                return ++s->v;
        }

        save_value(index, 0);

        return 1;
}

__noinline int baz(struct S **s)
{
        if (s)
                *s = 0;

        return 0;
}

SEC("cgroup_skb/ingress")
int test_cls(struct __sk_buff *skb)
{
        __u32 index = 0;

        {
                const int v = foo(index++, 0);

                save_value(index++, v);
        }

        {
                struct S s = { .v = 100 };

                foo(index++, &s);
                save_value(index++, s.v);
        }

        {
                global_variable.v = 42;
                bar(index++, &global_variable);
                save_value(index++, global_variable.v);
        }

        {
                struct S v, *p = &v;

                baz(&p);
                save_value(index++, !p);
        }

        return 0;
}

char _license[] SEC("license") = "GPL";