main.cpp

//
//  main.cpp
//  trick
//
//  Created by BlueCocoa on 2016/11/21.
//  Copyright © 2016 BlueCocoa. All rights reserved.
//

#import <iostream>
#import <string>
#import "trick.hpp"

using namespace std;
using namespace trick;

#pragma mark Hook function

__attribute__((visibility("hidden")))
void cpp_func(std::string via) {
    printf("cpp_func called %s\n", via.c_str());
}

static void (*orig_func)(std::string via);
void my_func(std::string via) {
    orig_func(via);
}

#pragma mark Hook global ariables

class foo {
public:
    int data;
};

static foo glob_foo;
static std::string glob_var;

int main(int argc, const char * argv[]) {
    glob_foo.data = 233;
    glob_var = "Hello";
    
    // Please note that the symbol name possibly *VARIES* when use different compilers and settings
    // In this example,
    /*
     
     Apple LLVM version 8.0.0 (clang-800.0.42.1)
     Target: x86_64-apple-darwin16.1.0
     Thread model: posix
     Xcode version: Version 8.1 (8B62)
     
     */
    
#pragma mark symbol
    
    mach_vm_address_t addr = trick::get_symbol_address("_ZL8glob_var");
    printf("_ZL8glob_var: %p\n", (void *)addr);
    
    trick::get_symbol<std::string>("_ZL8glob_var") += " World!";
    printf("glob_var: %s\n", glob_var.c_str());
    
    addr = trick::get_symbol_address("_ZL8glob_foo");
    printf("_ZL8glob_foo: %p\n", (void *)addr);
    
    trick::get_symbol<class foo>("_ZL8glob_foo").data = 2333;
    printf("glob_foo.data: %d\n", glob_foo.data);
    
#pragma mark function
    
    cpp_func("directly");
    
    addr = trick::get_symbol_address("_Z8cpp_funcNSt3__112basic_stringIcNS_11char_traitsIcEENS_9allocatorIcEEEE");
    printf("void cpp_func(std::string): %p\n", (void *)addr);
    
    trick::get_function<void(*)(std::string)>("_Z8cpp_funcNSt3__112basic_stringIcNS_11char_traitsIcEENS_9allocatorIcEEEE")("via trick::get_function");
    return 0;
}