meh

#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <chrono>
#include <thread>

#include <sys/types.h>
#include <sys/ptrace.h>
#include <unistd.h>
#include <sys/user.h>

#ifdef __x86_64__
typedef struct
{
    unsigned long r15;
    unsigned long r14;
    unsigned long r13;
    unsigned long r12;
    unsigned long rbp;
    unsigned long rbx;
    unsigned long r11;
    unsigned long r10;
    unsigned long r9;
    unsigned long r8;
    unsigned long rax;
    unsigned long rcx;
    unsigned long rdx;
    unsigned long rsi;
    unsigned long rdi;
    unsigned long orig_rax;
    unsigned long rip;
    unsigned long cs;
    unsigned long eflags;
    unsigned long rsp;
    unsigned long ss;
    unsigned long fs_base;
    unsigned long gs_base;
    unsigned long ds;
    unsigned long es;
    unsigned long fs;
    unsigned long gs;
} user_regs_struct;
#elif defined __i386__
typedef struct
{
    unsigned long   ebx;
    unsigned long   ecx;
    unsigned long   edx;
    unsigned long   esi;
    unsigned long   edi;
    unsigned long   ebp;
    unsigned long   eax;
    unsigned long   ds;
    unsigned long   es;
    unsigned long   fs;
    unsigned long   gs;
    unsigned long   orig_eax;
    unsigned long   eip;
    unsigned long   cs;
    unsigned long   eflags;
    unsigned long   esp;
    unsigned long   ss;
} user_regs_struct;
#elif defined(__arm__)

#endif

void SetRegisters(pid_t pid)
{
    user_regs_struct regs;
    long result = ptrace(PTRACE_GETREGS, pid, NULL, &regs);
    if (result == 0)
    {
        #ifdef __x86_64__
        std::cout<<"Read Register: "<<std::hex<<regs.rax<<"\n";
        regs.rax = 0xDEADBEEF;
        #elif defined __i386__
        std::cout<<"Read Register: "<<std::hex<<regs.eax<<"\n";
        regs.eax = 0xDEADBEEF;
        #endif
        result = ptrace(PTRACE_SETREGS, pid, NULL, &regs);

        if (result == 0)
        {
            std::cout<<"Failed To Set Registers\n";
        }
    }
    else
    {
        std::cout<<"Failed To Read Registers\n";
    }
}

void GetRegisters(pid_t pid)
{
    struct user_regs_struct regs;
    long result = ptrace(PTRACE_GETREGS, pid, NULL, &regs);

    if (result == 0)
    {
        #ifdef __x86_64__
        std::cout<<"Read Registers: "<<regs.rax<<"\n";
        #elif defined __i386__
        std::cout<<"Read Registers: "<<regs.eax<<"\n";
        #endif
    }
}

template<typename T>
void ReadPages(pid_t pid, void* offset, T* value)
{
    char buffer[256] = {0};
    sprintf(buffer, "/proc/%d/mem", pid);
    FILE* fd = fopen(buffer, "r");
    wait(pid, nullptr, 0);
    fseek(fd, reinterpret_cast<std::ptrdiff_t>(offset), SEEK_SET);
    fread(value, 1, sizeof(T), fd);
    fclose(fd);
}

int main(int argc, const char * argv[]) {

    if (argc > 2) {
        std::boolalpha(std::cout);
        std::int32_t pid = std::atoi(argv[1]);
        std::ptrdiff_t addr = std::atoll(argv[2]);
        std::cout<<"ATTACHING TO PROCESS: "<<pid<<"\n";

        std::int32_t result = ptrace(PT_ATTACH, pid, nullptr, 0);
        std::cout<<"ATTACHED: "<<static_cast<bool>(result == 0)<<"\n";

        std::this_thread::sleep_for(std::chrono::seconds(1));

        GetRegisters(pid);
        SetRegisters(pid);

        int val = 0;
        ReadPages<int>(pid, addr, &val);
        std::cout<<"Read Integer: "<<val<<" at Address: "<<std::hex<<reinterpret_cast<void*>(addr)<<"\n";


        result = ptrace (PT_CONTINUE, pid, nullptr, 0);
        std::cout<<"CONTINUED: "<<static_cast<bool>(result == 0)<<"\n";

        result = ptrace (PT_DETACH, pid, nullptr, 0);
        std::cout<<"DETACHED: "<<static_cast<bool>(result == 0)<<"\n";
    }
    else {
        std::cout<<"Terminating.. PID or Addr Argument Missing..\n";
    }

    return 0;
}