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#include "idt.h"
#include "util.h"

void irq_install_handler(int n, uint32 handler) {
    idt[n].low_offset = low_16(handler);
    idt[n].sel = KERNEL_CS;
    idt[n].always0 = 0;
    idt[n].flags = 0x8E; 
    idt[n].high_offset = high_16(handler);
}

void set_idt() {
    idt_reg.base = (uint32) &idt;
    idt_reg.limit = IDT_ENTRIES * sizeof(idt_gate_t) - 1;
    __asm__ __volatile__("lidtl (%0)" : : "r" (&idt_reg));
}

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#ifndef IDT_H
#define IDT_H

#include "types.h"

#define KERNEL_CS 0x08

typedef struct {
    uint16 low_offset;
    uint16 sel; 
    uint8 always0;
    uint8 flags; 
    uint16 high_offset;
} __attribute__((packed)) idt_gate_t ;

typedef struct {
    uint16 limit;
    uint32 base;
} __attribute__((packed)) idt_register_t;

#define IDT_ENTRIES 256
idt_gate_t idt[IDT_ENTRIES];
idt_register_t idt_reg;

void irq_install_handler(int n, uint32 handler);
void set_idt();

#endif

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#include "util.h"

void memory_copy(char *source, char *dest, int nbytes) {
    int i;
    for (i = 0; i < nbytes; i++) {
        *(dest + i) = *(source + i);
    }
}

void memory_set(uint8 *dest, uint8 val, uint32 len) {
    uint8 *temp = (uint8 *)dest;
    for ( ; len != 0; len--) *temp++ = val;
}

void int_to_ascii(int n, char str[]) {          
    int i, sign;
    if ((sign = n) < 0) n = -n;
    i = 0;
    do {
        str[i++] = n % 10 + '0';         
    } while ((n /= 10) > 0);

    if (sign < 0) str[i++] = '-';
    str[i] = '\0';
}

Code: Select all

#ifndef UTIL_H
#define UTIL_H

#include "types.h"

void memory_copy(char *source, char *dest, int nbytes);
void memory_set(uint8 *dest, uint8 val, uint32 len);
void int_to_ascii(int n, char str[]);          

Code: Select all

void irq_install_handler()(int n, uint32 handler)