// SPDX-License-Identifier: GPL-2.0-only
/* Copyright (c) 2017 Facebook
 */
#include <uapi/linux/bpf.h>
#include <bpf/bpf_helpers.h>

#if !defined(__aarch64__)
struct syscalls_enter_open_args {
        unsigned long long unused;
        long syscall_nr;
        long filename_ptr;
        long flags;
        long mode;
};
#endif

struct syscalls_exit_open_args {
        unsigned long long unused;
        long syscall_nr;
        long ret;
};

struct syscalls_enter_open_at_args {
        unsigned long long unused;
        long syscall_nr;
        long long dfd;
        long filename_ptr;
        long flags;
        long mode;
};

struct {
        __uint(type, BPF_MAP_TYPE_ARRAY);
        __type(key, u32);
        __type(value, u32);
        __uint(max_entries, 1);
} enter_open_map SEC(".maps");

struct {
        __uint(type, BPF_MAP_TYPE_ARRAY);
        __type(key, u32);
        __type(value, u32);
        __uint(max_entries, 1);
} exit_open_map SEC(".maps");

static __always_inline void count(void *map)
{
        u32 key = 0;
        u32 *value, init_val = 1;

        value = bpf_map_lookup_elem(map, &key);
        if (value)
                *value += 1;
        else
                bpf_map_update_elem(map, &key, &init_val, BPF_NOEXIST);
}

#if !defined(__aarch64__)
SEC("tracepoint/syscalls/sys_enter_open")
int trace_enter_open(struct syscalls_enter_open_args *ctx)
{
        count(&enter_open_map);
        return 0;
}
#endif

SEC("tracepoint/syscalls/sys_enter_openat")
int trace_enter_open_at(struct syscalls_enter_open_at_args *ctx)
{
        count(&enter_open_map);
        return 0;
}

SEC("tracepoint/syscalls/sys_enter_openat2")
int trace_enter_open_at2(struct syscalls_enter_open_at_args *ctx)
{
        count(&enter_open_map);
        return 0;
}

#if !defined(__aarch64__)
SEC("tracepoint/syscalls/sys_exit_open")
int trace_enter_exit(struct syscalls_exit_open_args *ctx)
{
        count(&exit_open_map);
        return 0;
}
#endif

SEC("tracepoint/syscalls/sys_exit_openat")
int trace_enter_exit_at(struct syscalls_exit_open_args *ctx)
{
        count(&exit_open_map);
        return 0;
}

SEC("tracepoint/syscalls/sys_exit_openat2")
int trace_enter_exit_at2(struct syscalls_exit_open_args *ctx)
{
        count(&exit_open_map);
        return 0;
}