// SPDX-License-Identifier: GPL-2.0
#include <vmlinux.h>
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h>
#include <stdbool.h>
#include "bpf_misc.h"

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

int pid = 0;

int idx_entry = 0;
int idx_return = 0;

__u64 test_uprobe_cookie_entry[6];
__u64 test_uprobe_cookie_return[3];

static int check_cookie(struct pt_regs *ctx)
{
        __u64 *cookie = bpf_session_cookie(ctx);

        if (bpf_session_is_return(ctx)) {
                if (idx_return >= ARRAY_SIZE(test_uprobe_cookie_return))
                        return 1;
                test_uprobe_cookie_return[idx_return++] = *cookie;
                return 0;
        }

        if (idx_entry >= ARRAY_SIZE(test_uprobe_cookie_entry))
                return 1;
        *cookie = test_uprobe_cookie_entry[idx_entry];
        return idx_entry++ % 2;
}


SEC("uprobe.session//proc/self/exe:uprobe_session_recursive")
int uprobe_recursive(struct pt_regs *ctx)
{
        if (bpf_get_current_pid_tgid() >> 32 != pid)
                return 1;

        return check_cookie(ctx);
}