Now this should be complete

Added basic shell and fixed various bugs...now iceos should be
"complete".

README.md

@@ -21,12 +21,10 @@ iceOS already have/will have the following features:
 - [x] Bare metal booting;
 - [x] VGA driver;
 - [x] Interrupts implementation;
-- [ ] PIC & PIT implementation;
+- [x] PIC & PIT implementation;
-- [ ] PS2 driver;
+- [x] PS2 driver;
 - [x] Support for x86 architecture;
 - [x] GRUB as bootloader;
-- [ ] Paging;
-- [ ] Dynamic memory allocation(heap).
 
 ## Resources
 This project is made with different kind of resources and different kind of knowledges, before starting it i read/studied the following resources:

build.sh

@@ -27,6 +27,10 @@ cp kernel/drivers/*.o obj/
 make -C kernel/libc
 cp kernel/libc/*.o obj/
 
+# Shell
+make -C kernel/shell
+cp kernel/shell/*.o obj/
+
 # Linking
 i686-elf-ld -melf_i386 -nostdlib -O2 -T link.ld -o isodir/boot/iceOS.bin obj/*.o
 

kernel/drivers/isr.c

@@ -63,7 +63,6 @@ void isr_handler(registers_t regs) {
                  WHITE,
                  BLACK
         );
-        kprint((uint8_t*)"\n");
     }
 }
 

kernel/drivers/keyboard.c

@@ -9,11 +9,110 @@
  * This device should not exists anymore in any modern computer 
  * motherboard; however the CPU(or the motherboard?) should be able to 
  * simulate it even if we're using some USB keyboard.
+ * Apart of that the keyboard will be listen on IRQ1(33),
+ * so we have to register an ISR for that.
 */
 
 #include "keyboard.h"
 #include "isr.h"
 #include "ports.h"
 #include "tty.h"
-#include "../libc/string.h"
+#include "../shell/shell.h"
 #include "../libc/stdio.h"
+
+static void keyboard_callback();
+
+/* Keyboard scan codes map , layout is: standard US keyboard */
+uint8_t keyboard_scan_codes[] = {
+    0, (uint8_t)27, (uint8_t)'1', (uint8_t)'2', (uint8_t)'3', (uint8_t)'4', (uint8_t)'5', (uint8_t)'6', (uint8_t)'7', (uint8_t)'8',
+    (uint8_t)'0', (uint8_t)'0', (uint8_t)'-', (uint8_t)'=', (uint8_t)'\b',
+    (uint8_t)'\t',
+    (uint8_t)'q', (uint8_t)'w', (uint8_t)'e', (uint8_t)'r',
+    (uint8_t)'t', (uint8_t)'y', (uint8_t)'u', (uint8_t)'i', (uint8_t)'o', (uint8_t)'p', (uint8_t)'[', (uint8_t)']', (uint8_t)'\n',
+    0,
+    (uint8_t)'a', (uint8_t)'s', (uint8_t)'d', (uint8_t)'f', (uint8_t)'g', (uint8_t)'h', (uint8_t)'j', (uint8_t)'k', (uint8_t)'l', (uint8_t)';',
+    (uint8_t)'\'', (uint8_t)'`', 0,
+    (uint8_t)'\\', (uint8_t)'z', (uint8_t)'x', (uint8_t)'c', (uint8_t)'v', (uint8_t)'b', (uint8_t)'n',
+    (uint8_t)'m', (uint8_t)',', (uint8_t)'.', (uint8_t)'/', 0,
+    (uint8_t)'*',
+
+    0, // Alt
+  (uint8_t)' ', // Spacebar
+    0, // Caps lock
+    0, // 59 - F1 key
+    0, // 59 - F1 key
+    0, 0, 0, 0, 0, 0, 0, 0,
+    0, // F10
+    0, // 69 - Num lock
+    0, // Scroll lock
+    0, // Home key
+    0, // Up arrow
+    0, // Page up
+   (uint8_t)'-',
+    0, // Left arrow
+    0, 
+    0, // Right arrow
+   (uint8_t)'+',
+    0, // 79 End key
+    0, // Down arrow 
+    0, // Page down
+    0, // Insert key
+    0, // Delete key
+    0, 0, 0,
+    0, // F11 key
+    0, // F12 key
+    0 // Others key are undefined
+};
+
+uint8_t command[512]; // Max length of a single command
+uint8_t temp[512];
+uint32_t cmd_index = 0;
+uint32_t shiftdown = 0;
+
+void clear() {
+    for(uint16_t i = 0; i < 512; i++)
+        command[i] = 0;
+}
+
+void clear_tmp(void) {
+    for(uint16_t i = 0; i < 512; i++)
+        command[i] = 0;
+}
+
+static void keyboard_callback() {
+    uint8_t scan_code = inb(KB_DATA_PORT); // Read from keyboard
+    uint8_t keycode = keyboard_scan_codes[scan_code]; // Get ASCII value
+
+    if(scan_code & 0x80) {
+        if(scan_code == 0xAA || scan_code == 0x86)
+            shiftdown = 0;
+    } else {
+        // Handle backspace
+        if(keycode == 0x08) {
+            if(cmd_index <= 0) // If at start of the prompt
+                return; // Do not delete it.
+            cmd_index--; // Otherwise go back
+
+        for(uint32_t i = 0; i < cmd_index; ++i)
+            temp[i] = command[i];
+        clear();
+        for(uint32_t i = 0; i < cmd_index; ++i)
+            command[i] = temp[i];
+        clear_tmp();
+        backspace();
+        } else if(keycode == 0x0A) { // Handle Enter
+            processCommand(command);
+            cmd_index = 0;
+            clear();
+            init_prompt();
+        } else {
+            printf("%c", keycode);
+            command[cmd_index] = keycode;
+            cmd_index++;
+        }
+    }
+}
+
+void init_keyboard() {
+    register_interrupt_handler(IRQ1, &keyboard_callback);
+}

kernel/drivers/keyboard.h

@@ -10,48 +10,8 @@
 
 #include <stdint.h>
 
+#define KB_DATA_PORT 0x60 // Keyboard serial port
+
 void init_keyboard();
 
-/* Keyboard scan codes map */
-uint8_t *keyboard_scan_codes[] = {
-    0, (uint8_t*)27, (uint8_t*)'1', (uint8_t*)'2', (uint8_t*)'3', (uint8_t*)'4', (uint8_t*)'5', (uint8_t*)'6', (uint8_t*)'7', (uint8_t*)'8',
-    (uint8_t*)'0', (uint8_t*)'0', (uint8_t*)'-', (uint8_t*)'=', (uint8_t*)'\b',
-    (uint8_t*)'\t',
-    (uint8_t*)'q', (uint8_t*)'w', (uint8_t*)'e', (uint8_t*)'r',
-    (uint8_t*)'t', (uint8_t*)'y', (uint8_t*)'u', (uint8_t*)'i', (uint8_t*)'o', (uint8_t*)'p', (uint8_t*)'[', (uint8_t*)']', (uint8_t*)'\n',
-    0,
-    (uint8_t*)'a', (uint8_t*)'s', (uint8_t*)'d', (uint8_t*)'f', (uint8_t*)'g', (uint8_t*)'h', (uint8_t*)'j', (uint8_t*)'k', (uint8_t*)'l', (uint8_t*)';',
-    (uint8_t*)'\'', (uint8_t*)'`', 0,
-    (uint8_t*)'\\', (uint8_t*)'z', (uint8_t*)'x', (uint8_t*)'c', (uint8_t*)'v', (uint8_t*)'b', (uint8_t*)'n',
-    (uint8_t*)'m', (uint8_t*)',', (uint8_t*)'.', (uint8_t*)'/', 0,
-    (uint8_t*)'*',
-
-    0, // Alt
-  (uint8_t*)' ', // Spacebar
-    0, // Caps lock
-    0, // 59 - F1 key
-    0, // 59 - F1 key
-    0, 0, 0, 0, 0, 0, 0, 0,
-    0, // F10
-    0, // 69 - Num lock
-    0, // Scroll lock
-    0, // Home key
-    0, // Up arrow
-    0, // Page up
-   (uint8_t*)'-',
-    0, // Left arrow
-    0, 
-    0, // Right arrow
-   (uint8_t*)'+',
-    0, // 79 End key
-    0, // Down arrow 
-    0, // Page down
-    0, // Insert key
-    0, // Delete key
-    0, 0, 0,
-    0, // F11 key
-    0, // F12 key
-    0 // Others key are undefined
-};
-
 #endif

kernel/drivers/ports.h

@@ -8,7 +8,7 @@
  * @param port: Output port to send data to.
  * @param data: The actual data to send to port
 */
-void outb(uint16_t port, uint8_t data);
+void outb(uint16_t port, uint16_t data);
 
 /* inb:
  * Fetch data from a port, return a char

kernel/drivers/tty.c

@@ -6,7 +6,7 @@
 // Also define a 2 byte pointer because cells are 16 bits wide
 #define UVGA_PTR ((uint16_t *)VIDEO_MEM_ADDR)
 
-static uint32_t fb_col = 0; // X
+static uint32_t fb_col = 1; // X
 static uint32_t fb_row = 0; // Y
 
 void write_cell(int16_t i, uint8_t c, uint8_t fg, uint8_t bg) {
@@ -70,12 +70,12 @@ void kprint(uint8_t *buf) {
 }
 
 void init_prompt() {
-    uint8_t *prompt = (uint8_t*)"\nuser@iceOS-$ ";
+    uint8_t *prompt = (uint8_t*)"\nring0@iceOS-$ ";
-    kprint_c(prompt, strlen(prompt), LIGHT_GREEN, BLACK);
+    kprint_c(prompt, strlen(prompt), LIGHT_RED, BLACK);
 }
 
 void clear_prompt() {
-    fb_col = 0;
+    fb_col = 1;
     fb_row = 0;
 
     for(uint32_t i = 0; i < (VGA_WIDTH * VGA_HEIGHT); i++)
@@ -100,6 +100,6 @@ void newline() {
     else // Otherwise scroll framebuffer
         scroll();
 
-    fb_col = 0;
+    fb_col = 1;
     move_cursor(fb_col + (fb_row * VGA_WIDTH));
 }

kernel/kernel_main.c

@@ -9,21 +9,17 @@
 #include "drivers/gdt.h"
 #include "drivers/idt.h"
 #include "drivers/timer.h"
-#include "libc/stdio.h"
+#include "drivers/keyboard.h"
+#include "shell/shell.h"
 
 void kernel_main() {
     gdt_setup(); // Setup Global Descriptor Table
     idt_setup(); // Setup Interrupt Descriptor Table
 
     clear_prompt();
+    iceos_ascii_logo();
     init_prompt(); // Initialize frame buffer
-    //puts("Hello World!");
+    init_keyboard(); // Initialize keyboard driver
-    init_timer(1);
 
-    /*
+    // init_timer(1); // Only for debug purposes
-    // Testing some interrupts
-    asm("int $0"); // Division by zero
-    asm("int $4"); // Stack overflow
-    asm("int $1"); // Page fault 
-    */
 }

kernel/libc/stdio.c

@@ -32,7 +32,7 @@ int printf(const char *format, ...) {
                     kprint(buf);
                     break;
                 case 'c':
-                    s = va_arg(ap, uint8_t*);
+                    c = (uint8_t)va_arg(ap, uint32_t);
                     kprint_c(&c, 1, WHITE, BLACK);
                     break;
                 case 's':
@@ -49,6 +49,11 @@ int printf(const char *format, ...) {
     return 0;
 }
 
+int printf_color(const char *format, uint8_t fg, uint8_t bg) {
+    kprint_c((uint8_t*)format, strlen((uint8_t*)format), fg, bg);
+    return 0;
+}
+
 void puts(const char *buf) {
     printf("%s\n", buf);
 }

kernel/libc/stdio.h

@@ -14,6 +14,7 @@
 #include <stdarg.h>
 
 int printf(const char *format, ...);
+int printf_color(const char *format, uint8_t fg, uint8_t bg); // Only for string for now
 void puts(const char *buf);
 
 #endif

kernel/shell/Makefile

@@ -0,0 +1,10 @@
+OBJS = shell.o
+
+CC = i686-elf-gcc # cross-compiler
+CFLAGS = -m32 -fno-stack-protector -ffreestanding -Wall -Wextra -Werror -g -c
+
+
+all:${OBJS}
+
+%.o: %.c
+	$(CC) $(CFLAGS) $< -o $@

kernel/shell/shell.c

@@ -0,0 +1,87 @@
+#include "shell.h"
+#include "../libc/string.h"
+#include "../libc/stdio.h"
+#include "../drivers/tty.h"
+#include "../drivers/ports.h"
+
+void helper() {
+    puts("\nList of available commands:\n"
+         "\nhelp        - Print this helper"
+         "\nint         - Test some interrupts"
+         "\nbanner      - Show banner"
+         "\nclear, cls  - Clear the screen"
+         "\nabout       - About this kernel"
+         "\nreboot      - Reboot the system"
+        );
+}
+
+void test_interrupts() {
+    // Testing some interrupts
+    asm("int $0"); // Division by zero
+    asm("int $4"); // Stack overflow
+    asm("int $1"); // Page fault 
+}
+
+void about() {
+    printf_color("\n====== IceOS v0.0.1 (c) 2019 Marco 'icebit' Cetica ======\n\n",
+                 LIGHT_CYAN, BLACK);
+    printf_color(
+        "iceOS is a x86 monolithic kernel written in C from scratch.\n"  
+        "This project doesn't aim to be a fully functional operating system\n"
+        "with tons of drivers and graphical applications,\nit's just a learning tool" 
+        "to teach myself concepts like\nOperating Systems, Computer Architecture and Digital Electronics.\n" 
+        "\n\n"
+        "iceOS comes with the following features:\n"
+        "- Bare metal booting;\n"
+        "- VGA driver;\n"
+        "- Interrupts implementation;\n"
+        "- PIC & PIT implementation;\n"
+        "- PS2 driver;\n"
+        "- Support for x86 architecture;\n"
+        "- GRUB as bootloader;\n",
+    LIGHT_GREEN, BLACK);
+}
+
+void reboot() {
+    uint8_t tmp;
+    asm("cli"); // First disable all interrupts
+
+    // Clear keyboard buffers
+    do {
+        tmp = inb(0x64); // Keyboard interface
+        if(check_flag(tmp, 0) != 0)
+            inb(0x60); // Clear keyboard data
+    } while(check_flag(tmp, 1) != 0);
+
+    outb(0x64, 0xFE); // Reset the CPU
+}
+
+void iceos_ascii_logo() {
+    printf_color(
+"\n\n###  #####  ####### #######  #####\n"
+" #  #     # #       #     # #     #\n"
+" #  #       #       #     # #       \n"
+" #  #       #####   #     #  #####  \n"
+" #  #       #       #     #       # \n"
+" #  #     # #       #     # #     # \n"
+"###  #####  ####### #######  #####  \n"
+"\n     (c) Marco Cetica 2019\n",
+ LIGHT_MAGENTA, BLACK);
+ }
+
+void processCommand(uint8_t *cmd) {
+    if(strcmp(cmd, (uint8_t*)"help") == 0)
+        helper();
+    else if(strcmp(cmd, (uint8_t*)"int") == 0)
+        test_interrupts();
+    else if(strcmp(cmd, (uint8_t*)"clear") == 0 || strcmp(cmd, (uint8_t*)"cls") == 0)
+        clear_prompt();
+    else if(strcmp(cmd, (uint8_t*)"about") == 0)
+        about();
+    else if(strcmp(cmd, (uint8_t*)"banner") == 0)
+        iceos_ascii_logo();
+    else if(strcmp(cmd, (uint8_t*)"reboot") == 0)
+        reboot();
+    else
+        puts("\nCommand not found!");
+}

kernel/shell/shell.h

@@ -0,0 +1,20 @@
+/**************************************
+ *          iceOS Kernel              *
+ * Developed by Marco 'icebit' Cetica * 
+ *            (c) 2019                *
+ *       Released under GPLv3         *
+ * https://github.com/ice-bit/iceOS   *
+ ***************************************/
+#ifndef _SHELL_H_
+#define _SHELL_H_
+
+#include <stdint.h>
+
+#define bit(n) (1 << (n))
+#define check_flag(flags, n) ((flags) & bit(n))
+
+void helper();
+void processCommand(uint8_t *cmd);
+void iceos_ascii_logo();
+
+#endif