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#include "../cpu/idt.h"
#include "../cpu/isr.h"
#include "../cpu/timer.h"
#include "../drivers/ports.h"
#include "../drivers/hdd.h"
#include "../drivers/display.h"

#define ET(x) printf("Error Trace %s\n", #x);
#define PUSH_ALL asm volatile ( \
        "pusha \n\t" \
        : : : "memory" );

#define POP_ALL asm volatile ( \
        "popa \n\t" \
        : : : "memory" );

void* search_signature(void* start_address, size_t size, uint32_t signature) {
    for (size_t i = 0; i < size - sizeof(uint32_t) + 1; i++) {
        uint32_t value = *((uint32_t*)(start_address + i));
        if (value == signature) {
            // Signature found, return the address
            return (start_address + i);
        }
    }

    // Signature not found in the given range
    return NULL;
}

int check = 0;
void start_kernel() {
    if(check == 1) {
        clear_screen();
        ET(start)
        while(1) {}
    }
    PUSH_ALL;

    readFromHardDrive(33, 2880, (void*)0x200000);

    void* sig = 0x200000;
    void* jmp = 0x1000;
    while(sig = search_signature(sig, 512*2880, 0xDEADBEEF)) {
        printf("signature found at %p\n", sig);
        jmp = sig;
        sig++;
    }

    memcpy(0x100000, jmp-9, 0x100000);
    hexDump(0x100000, 64); // everything is in place

    getch();

    POP_ALL;

    ET(usw)
    check = 1;

    // Rufe den Eintrittspunkt von kernel2.bin auf
    void (*functionPointer)() = (void*)0x100000; // kernel_start_main;

    printf("functionPtr = %p\n", functionPointer);

    functionPointer();

    ET(etc)
}

[bits 32]
BEGIN_32BIT:

   pusha
   mov esi, 0x1000  ; Source address
   mov edi, 0x100000 ; Destination address
   mov ecx, 0xFFFF  ; Length of data to move
   cld             ; Set the direction flag to forward
   rep movsb       ; Move the data from source to destination
   popa

   call 0x100000 ; Give control to the kernel
   jmp $ ; Stay here when the kernel returns control to us (if ever)