MyCustomOS/kernel.cpp at master · OdilonDamasceno/MyCustomOS · GitHub

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#include "types.h"
#include "gdt.h"

void printf(char* str)
{
    static uint16_t* VideoMemory = (uint16_t*)0xb8000;

    static uint8_t x=0, y=0;

    for (int i = 0; str[i] != '\0'; ++i)
    {
        switch (str[i])
        {
            case '\n':
                x=0;
                y++;
                   break;
            default:
                VideoMemory[80*y+x] = (VideoMemory[80*y+x] & 0xFF00) | str[i];
                x++;
                break;
        }

        if(x>=80)
        {
            x=0;
            y++;
        }
        if (y>=25)
        {
            for(y=0;y<25; y++)
                for(x=0;x<80;x++)
                    VideoMemory[80*y+x] = (VideoMemory[80*y+x] & 0xFF00) | ' ';

            x=0;
            y=0;
        }

    }

}

typedef void (*constructor)();
extern "C" constructor start_ctors;
extern "C" constructor end_ctors;
extern "C" void callConstructors()
{
    for(constructor* i = &start_ctors; i != &end_ctors; i++)
        (*i)();
}

extern "C" void kernelMain(const void* multiboot_structure, uint32_t /*magicnumber*/)
{
    printf("Hello, world! Feito por Odilon Damasceno github.com/OdilonDamasceno\n");
    printf("Hello, world! Feito por Odilon Damasceno github.com/OdilonDamasceno");
    GlobalDescriptorTable gdt;
    while (1);
}