main.c

#include "extra.h"

#define PIC1_C 0x20
#define PIC1_D 0x21
#define PIC2_C 0xa0
#define PIC2_D 0xa1

#define ICW1_DEF 0x10
#define ICW1_ICW4 0x01
#define ICW4_x86 0x01


void cls();
void setMonitorColor(char);

void printString(char*);
void printChar(char);

void scroll();
void printColorString(char* , char);
void printColorChar(char , char);

void getDecAscii(int);



void initIDT();
extern void loadIdt();
extern void isr1_Handler();
void handleKeypress(int);
void pressed(char);
void picRemap();


unsigned char inportb(unsigned short);
void outportb(unsigned short , unsigned char);



char NumberAscii[10];
int CELL;

char COMMAND[21];
int i=0;

struct IDT_ENTRY{
    unsigned short base_Lower;
    unsigned short selector;
    unsigned char zero;
    unsigned char flags;
    unsigned short base_Higher;
};

struct IDT_ENTRY idt[256];
extern unsigned int isr1;
unsigned int base;


int start(){
   TM_START=(char*) 0xb8000;
   CELL=0;
   base= (unsigned int)&isr1;
   cls();
   setMonitorColor(0x07);

   char FirstMain[] = "FLIP-OS: VERSION 1.0.0.0\n";
   char FirstCLI[] = "FLIP-OS Team. All rights reserved (c)\n\n";
   char OSdescrip[] = "FLIP-OS > ";

   printString(FirstMain);
   printString(FirstCLI);
   printColorString(OSdescrip , 0x0f);

   initIDT();
}


void cls(){
    int i=0;
    CELL=0;
    while(i<(2*80*25)){
        *(TM_START+i)=' ';
        i+=2;
    }
}


void setMonitorColor(char Color){
    int i=1;
    while(i<(2*80*25)){
        *(TM_START+i)=Color;
        i+=2;
    }
}


void printString(char* cA){
    int i=0;
    while(*(cA+i)!='\0'){
        printChar(*(cA+i));
        i++;
    }
}


void printChar(char c){
    if(CELL==2*80*25)
         scroll();
    if(c=='\n'){
        CELL=((CELL+160)-(CELL%160));
        return;
    }
    *(TM_START+CELL)=c;
    CELL+=2;
}


void scroll(){
    int i=160, y=0;
    while(i<2*80*25){
        *(TM_START + y) = *(TM_START + i);
        i += 2;
        y += 2;
    }
    CELL = 2 * 80 * 24;
    i = 0;
    while(i < 160){
    *(TM_START + CELL + i) = ' ';
    i += 2;
    }
}

void printColorString(char* c, char co){
    int i=0;
    while(*(c+i)!='\0'){
        printColorChar(*(c+i),co);
        i++;
    }
}


void printColorChar(char c, char co){
    if(CELL==2*80*25)
        scroll();
    if(c=='\n'){
        CELL = ((CELL + 160) - (CELL % 160));
        return;
    }
    *(TM_START + CELL) = c;
    *(TM_START + CELL + 1) = co;
     CELL += 2;
}



 void getDecAscii(int num){
    if(num == 0){
          NumberAscii[0] = '0';
          return;
    }
    char NUM[10];
    int i = 0 , j = 0;
    while(num > 0){
          NUM[i] = num % 10;
          num /= 10;
          i++;
    }
    i--;
    while(i >= 0){
           NumberAscii[j] = NUM[i];
          i--;
          j++;
    }
    NumberAscii[j] = 'J';
    j = 0;
    while(NumberAscii[j] != 'J'){
         NumberAscii[j] = '0' + NumberAscii[j];
         j++;
   }
 NumberAscii[j] = 0;
}

void initIDT(){
    idt[1].base_Lower=(base & 0xFFFF);
    idt[1].base_Higher=(base >> 16) & 0xFFFF;
    idt[1].selector= 0x08;
    idt[1].zero=0;
    idt[1].flags=0x8e;

    picRemap();

    outportb(0x21 , 0xfd);
    outportb(0xa1 , 0xff);

    loadIdt();
}

unsigned char inportb(unsigned short _port){
    unsigned char rv;
    __asm__ __volatile__ ("inb %1, %0" : "=a" (rv) : "dN" (_port));
    return rv;
}

void outportb(unsigned short _port, unsigned char _data){
    __asm__ __volatile__ ("outb %1, %0" : : "dN" (_port), "a" (_data));
}

extern void isr1_Handler(){
    handleKeypress(inportb(0x60));
    outportb(0x20 , 0x20);
    outportb(0xa0 , 0x20);
}

void handleKeypress(int code){
    char OSdescrip[] = "\nFLIP-OS > ";
    char Scancode[] = {
    0 , 0 , '1' , '2' ,
    '3' , '4' , '5' , '6' ,
    '7' , '8' , '9' , '0' ,
    '-' , '=' , 0 , 0 , 'Q' ,
    'W' , 'E' , 'R' , 'T' , 'Y' ,
    'U' , 'I' , 'O' , 'P' , '[' , ']' ,
    0 , 0 , 'A' , 'S' , 'D' , 'F' , 'G' ,
    'H' , 'J' , 'K' , 'L' , ';' , '\'' , '`' ,
    0 , '\\' , 'Z' , 'X' , 'C' , 'V' , 'B' , 'N' , 'M' ,
    ',' , '.' , '/' , 0 , '*' , 0 , ' '
    };
   
    if(code == 0x1c){
        COMMAND[i]='\0';
        i=0;
        strEval(COMMAND);
        printString(OSdescrip);
    }       
    else if(code < 0x3a)
         pressed(Scancode[code]);
}

void pressed(char key){
   if(i != 20){
       COMMAND[i] = key;
       i++;
       printChar(key);
    }
   else{
       blink();
   } 
   
}

void picRemap(){
    unsigned char a,b;

    a=inportb(PIC1_D);
    b=inportb(PIC2_D);

    outportb(PIC1_C , ICW1_DEF | ICW1_ICW4);
    outportb(PIC2_C , ICW1_DEF | ICW1_ICW4);

    outportb(PIC1_D , 0);
    outportb(PIC2_D , 8);

    outportb(PIC1_D , 4);
    outportb(PIC2_D , 2);
   
    outportb(PIC1_D , ICW4_x86);
    outportb(PIC2_D , ICW4_x86);
   
    outportb(PIC1_D , a);
    outportb(PIC2_D , b);

}