// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2019 Facebook

#include <linux/bpf.h>
#include <stdint.h>
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_core_read.h>

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

struct {
        char in[256];
        char out[256];
} data = {};

struct core_reloc_flavors {
        int a;
        int b;
        int c;
};

/* local flavor with reversed layout */
struct core_reloc_flavors___reversed {
        int c;
        int b;
        int a;
};

/* local flavor with nested/overlapping layout */
struct core_reloc_flavors___weird {
        struct {
                int b;
        };
        /* a and c overlap in local flavor, but this should still work
         * correctly with target original flavor
         */
        union {
                int a;
                int c;
        };
};

#define CORE_READ(dst, src) bpf_core_read(dst, sizeof(*(dst)), src)

SEC("raw_tracepoint/sys_enter")
int test_core_flavors(void *ctx)
{
        struct core_reloc_flavors *in_orig = (void *)&data.in;
        struct core_reloc_flavors___reversed *in_rev = (void *)&data.in;
        struct core_reloc_flavors___weird *in_weird = (void *)&data.in;
        struct core_reloc_flavors *out = (void *)&data.out;

        /* read a using weird layout */
        if (CORE_READ(&out->a, &in_weird->a))
                return 1;
        /* read b using reversed layout */
        if (CORE_READ(&out->b, &in_rev->b))
                return 1;
        /* read c using original layout */
        if (CORE_READ(&out->c, &in_orig->c))
                return 1;

        return 0;
}