root/Whitix/trunk/video/earlyconsole.c

#include <i386/ioports.h>
#include <typedefs.h>
#include <print.h>
#include <string.h>

BYTE* screen=(BYTE*)0xC00B8000;
int curX, curY;

void EarlyConsoleSetPos(int x, int y);

void EarlyConsoleNewLine()
{
        int i;
        
        curY++;
        curX=0;

        if (curY < 25)
                EarlyConsoleSetPos(curX, curY);
        else{
                /* Scroll the screen. */
                for (i=0; i < 24 ; i++)
                        memcpy ( &screen [ i*80*2] , &screen [ (i+1)*80*2 ] , 80*2);
                        
                /* Clear the last line of the console. */
                memsetw( &screen[ i*80*2 ] , 80*2, ((0x07 << 8) | (' ')));
                
                curY = 24;
        }
}

void EarlyConsolePrint(char* string, int length)
{
        int i;

        for (i=0; i<length; i++)
        {
                switch (string[i])
                {
                        case '\n':
                                EarlyConsoleNewLine();
                                break;

                        default:
                                screen[(curY*(80*2))+(curX*2)]=string[i];
                                screen[(curY*(80*2))+(curX*2)+1]=7;
                                curX++;
                }
                
                if (curX >= 80)
                        EarlyConsoleNewLine();
        }
}

void EarlyConsoleSetPos(int x, int y)
{
        WORD position=(y*80)+x;

        curX=x;
        curY=y;

        outb(0x3D4,14);
        outb(0x3D5,(BYTE)(position >> 8));
        outb(0x3D4,15);
        outb(0x3D5,(BYTE)(position & 0xFF));
}

void EarlyConsoleClearScreen()
{
        int i;

        for (i=0; i<(80*25*2); i+=2)
        {
                screen[i]=' ';
                screen[i+1]=7;
        }

        EarlyConsoleSetPos(0, 0);
}

void EarlyConsoleInit()
{
        EarlyConsoleClearScreen();
        KeSetOutput(EarlyConsolePrint);
}