mach-detours/sample/main.cpp

// Copyright (c) Lysann Tranvouez.  All rights reserved.

#include <cassert>
#include <cstring>

#include "mach_detours.h"

char* (*real_strerror)(int errno) = strerror;

static int counter = 0;

char* my_strerror(const int errno)
{
    counter++;
    return real_strerror(errno);
}

int main(int argc, const char* argv[])
{
    counter = 0;
    strerror(0);
    assert(counter == 0);

    detour_transaction_begin();
    detour_attach(reinterpret_cast<detour_func_t*>(&real_strerror), reinterpret_cast<detour_func_t>(my_strerror));
    detour_transaction_commit();

    assert(counter == 0);
    strerror(0);
    assert(counter == 1);

    detour_transaction_begin();
    detour_detach(reinterpret_cast<detour_func_t*>(&real_strerror), reinterpret_cast<detour_func_t>(my_strerror));
    detour_transaction_commit();

    assert(counter == 1);
    strerror(0);
    assert(counter == 1);

    return 0;
}