fixed the CMakeLists.txt so that it includes all the files in source as variables

src/drivers/io/io.c

@@ -1,7 +1,7 @@
 #include "io.h"
 
 /*
-    Common Ports 
+    Common Ports
     COM1: 0x3F8
     COM2: 0x2F8
     COM3: 0x3E8
@@ -24,6 +24,12 @@ char io_read_com()
     // TODO: Read from the COM port
     // Use the appropriate memory or I/O address to read from the port
     // Return the read data
+
+    char data = 0; // Initialize the variable to store the read data
+
+    // Read from the COM port and assign the read value to the 'data' variable
+
+    return data; // Return the read data
 }
 
 // Function to write to the COM port
@@ -40,6 +46,12 @@ char io_read_lpt()
     // TODO: Read from the LPT port
     // Use the appropriate memory or I/O address to read from the port
     // Return the read data
+
+    char data = 0; // Initialize the variable to store the read data
+
+    // Read from the LPT port and assign the read value to the 'data' variable
+
+    return data; // Return the read data
 }
 
 // Function to write to the LPT port

src/drivers/io/io.h

@@ -1,6 +1,8 @@
 #ifndef IO_H
 #define IO_H
 
+#include <stdint.h>
+
 // Function to initialize the COM and LPT ports
 void io_init();
 
@@ -16,4 +18,9 @@ char io_read_lpt();
 // Function to write to the LPT port
 void io_write_lpt(char data);
 
+// Function declarations for keyboard.c
+uint8_t inb(uint16_t port);
+void    outb(uint16_t port, uint8_t data);
+void    install_interrupt_handler(uint8_t interrupt, void (*handler)(void));
+
 #endif /* IO_H */

src/drivers/keyboard/keyboard.c

@@ -1,46 +1,56 @@
-#include <stdint.h>
+#include "keyboard.h"
+#include "../io/io.h"
 #include <stdbool.h>
 #include <stddef.h>
+#include <stdint.h>
 
 // Keyboard input buffer
 #define KEYBOARD_BUFFER_SIZE 32
 static uint8_t keyboard_buffer[KEYBOARD_BUFFER_SIZE];
-static size_t keyboard_buffer_head = 0;
-static size_t keyboard_buffer_tail = 0;
+static size_t  keyboard_buffer_head = 0;
+static size_t  keyboard_buffer_tail = 0;
 
 // Keyboard interrupt handler
-void keyboard_interrupt_handler() {
-  uint8_t scancode = inb(0x60);
+void keyboard_interrupt_handler()
+{
+    uint8_t scancode = inb(0x60);
 
-  // Add scancode to buffer
-  keyboard_buffer[keyboard_buffer_head] = scancode;
-  keyboard_buffer_head = (keyboard_buffer_head + 1) % KEYBOARD_BUFFER_SIZE;
+    // Add scancode to buffer
+    keyboard_buffer[keyboard_buffer_head] = scancode;
+    keyboard_buffer_head = (keyboard_buffer_head + 1) % KEYBOARD_BUFFER_SIZE;
 }
 
 // Initialize keyboard
-void keyboard_init() {
-  // Install keyboard interrupt handler
-  install_interrupt_handler(0x09, keyboard_interrupt_handler);
+void keyboard_init()
+{
+    // Install keyboard interrupt handler
+    set_interrupt_vector(0x09, keyboard_interrupt_handler);
+    enable_interrupt(0x09);
 
-  // Enable keyboard
-  outb(0x64, 0xAE);
-  while (inb(0x64) & 0x02);
-  outb(0x60, 0xF4);
-  while (inb(0x60) != 0xFA);
+    // Enable keyboard
+    outb(0x64, 0xAE);
+    while (inb(0x64) & 0x02)
+        ;
+    outb(0x60, 0xF4);
+    while (inb(0x60) != 0xFA)
+        ;
 }
 
 // Check if keyboard buffer is empty
-bool keyboard_buffer_empty() {
-  return keyboard_buffer_head == keyboard_buffer_tail;
+bool keyboard_buffer_empty()
+{
+    return keyboard_buffer_head == keyboard_buffer_tail;
 }
 
 // Read scancode from keyboard buffer
-uint8_t keyboard_read_scancode() {
-  if (keyboard_buffer_empty()) {
-    return 0;
-  }
+uint8_t keyboard_read_scancode()
+{
+    if (keyboard_buffer_empty())
+    {
+        return 0;
+    }
 
-  uint8_t scancode = keyboard_buffer[keyboard_buffer_tail];
-  keyboard_buffer_tail = (keyboard_buffer_tail + 1) % KEYBOARD_BUFFER_SIZE;
-  return scancode;
+    uint8_t scancode     = keyboard_buffer[keyboard_buffer_tail];
+    keyboard_buffer_tail = (keyboard_buffer_tail + 1) % KEYBOARD_BUFFER_SIZE;
+    return scancode;
 }

src/kernel/arch/x86/isr.c

@@ -2,6 +2,12 @@
 #include "idt.h"
 #include <stdio.h>
 
+#define TIMER_INTERRUPT       0x20
+#define KEYBOARD_INTERRUPT    0x21
+#define NETWORK_INTERRUPT     0x22
+#define DISK_INTERRUPT        0x23
+#define SERIAL_PORT_INTERRUPT 0x24
+
 // ISR table
 void (*isr_table[256])(struct isr_regs *regs);
 
@@ -18,6 +24,14 @@ void isr_handler(struct isr_regs *regs)
     {
         divide_error();
     }
+    else if (regs->int_no == 13)
+    {
+        general_protection_fault(regs);
+    }
+    else if (regs->int_no == 14)
+    {
+        page_fault(regs);
+    }
     else
     {
         void (*handler)(struct isr_regs *regs);
@@ -36,14 +50,31 @@ void divide_error()
     printf("Divide by zero error!\n");
 }
 
-void page_fault()
+void page_fault(struct isr_regs *regs)
 {
-    // Handle page fault exception
+    uint32_t faulting_address;
+
+    // Read the CR2 register to get the faulting address
+    asm volatile("mov %%cr2, %0" : "=r"(faulting_address));
+
+    // Print an error message with the faulting address
+    printf("Page fault at 0x%x, virtual address 0x%x\n", regs->eip,
+           faulting_address);
+
+    // Halt the system
+    for (;;)
+        ;
 }
 
-void general_protection_fault()
+void general_protection_fault(struct isr_regs *regs)
 {
-    // Handle general protection fault exception
+    // Handle the general protection fault exception
+    printf("General protection fault occurred!\n");
+    // Additional actions can be taken as needed
+
+    // Halt the system
+    for (;;)
+        ;
 }
 
 void double_fault()
@@ -52,9 +83,37 @@ void double_fault()
 }
 
 // Interrupt handlers
-void system_call()
+void system_call(struct isr_regs *regs)
 {
-    // Handle system call interrupt
+    // Get the system call number from the eax register
+    uint32_t syscall_number = regs->eax;
+
+    // Handle different system call numbers
+    switch (syscall_number)
+    {
+    case 1:
+        // Handle open() system call
+        // ...
+        break;
+    case 2:
+        // Handle read() system call
+        // ...
+        break;
+    case 3:
+        // Handle write() system call
+        // ...
+        break;
+    case 4:
+        // Handle close() system call
+        // ...
+        break;
+        // Add more cases for other system calls
+
+    default:
+        // Unknown system call number
+        printf("Unknown system call number: %d\n", syscall_number);
+        break;
+    }
 }
 
 void timer()
@@ -69,5 +128,32 @@ void keyboard()
 
 void device()
 {
-    // Handle device interrupt
+    // Determine the type of device interrupt
+    uint32_t interrupt_type = /* Read the interrupt type from the device */;
+
+    // Call the appropriate interrupt handler
+    switch (interrupt_type)
+    {
+    case TIMER_INTERRUPT:
+        timer();
+        break;
+    case KEYBOARD_INTERRUPT:
+        keyboard();
+        break;
+    case NETWORK_INTERRUPT:
+        network();
+        break;
+    case DISK_INTERRUPT:
+        disk();
+        break;
+    case SERIAL_PORT_INTERRUPT:
+        serial_port();
+        break;
+        // Add more cases for other types of device interrupts
+
+    default:
+        // Unknown interrupt type
+        printf("Unknown device interrupt type: %d\n", interrupt_type);
+        break;
+    }
 }

src/kernel/print.c

@@ -1,5 +1,7 @@
 #include "kernel.h"
+#include <stdio.h>
 
-void print_string(const char* str) {
-    // Your code to print the string to the screen goes here
+void print_string(const char *str)
+{
+    printf("%s", str);
 }