#include "internal.h"
#include <sys/shm.h>
#include <csignal>

Impl impl;

void *getSharedMemory(){
    impl.sharedMemorySize = 8000;

    auto id = shmget(impl.sharedMemoryKey, impl.sharedMemorySize, 0644u | IPC_CREAT);
    if(id == -1){
        //error
        impl.sharedMemorySize = 0;
        return nullptr;
    }

    void *data = shmat(id, nullptr, 0);
    if(data == (char*)(-1)){
        //error
        impl.sharedMemorySize = 0;
        return nullptr;
    }

    return data;
}

int getSharedMemorySize(){
    return impl.sharedMemorySize;
}

void sendSignal(pid_t pid, int signalNumber) {
    kill(pid, signalNumber);
}

void onSignal(int signalNumber, void(*callback)(int)) {
    signal(signalNumber, callback);
}

InterruptEntry *getInterrupTable(){
    return (InterruptEntry*)((char*)getSharedMemory() + sizeof(Registers) + 1024/*reserved*/);
}

bool callEvent(EventType type) {
    auto ivt = getInterrupTable();
    if(ivt[type].pid != 0){
        sendSignal(ivt[type].pid, ivt[type].signum);
    }
    return true;
}