adding nanoshell (KFS-2 bonus)

.gdb_history

@@ -1,7 +1,3 @@
-p idt
-p /x idt
-n
-next
 n
 cont
 n
@@ -254,3 +250,7 @@ n
 p formats
 p sizeof(formats)
 p sizeof(formats) / sizeof(format_t)
+b strcmp
+cont
+n
+p str2

Makefile

@@ -34,6 +34,7 @@ BASENAME			:=	kernel.c								\
 						system/boot/pic.s						\
 						system/boot/GDT/load.s					\
 						system/boot/GDT/init.c					\
+						system/boot/GDT/print_stack.c			\
 						system/boot/IDT/load.s					\
 						system/boot/IDT/init.c					\
 						system/boot/IDT/isr.c					\
@@ -49,6 +50,13 @@ BASENAME			:=	kernel.c								\
 						system/CPU/mode.c						\
 						system/CPU/interrupts.c					\
 						\
+						nanoshell/commands.c					\
+						nanoshell/shell.c						\
+						nanoshell/commands/reboot.c				\
+						nanoshell/commands/shutdown.c			\
+						nanoshell/commands/halt.c				\
+						nanoshell/commands/stack.c				\
+						\
 						libc/string/strlen.c					\
 						libc/string/strcpy.c					\
 						libc/string/strncpy.c					\

include/CPU/GDT.h

@@ -56,6 +56,12 @@
 
 #define KMCS 0x08 // Kernel Mode, Code Segment
 
+
+#define GET_STACK_POINTER(x) \
+	asm("mov %%esp, %0" : "=r" (x));
+#define GET_STACK_FRAME(x) \
+	asm("mov %%ebp, %0" : "=r" (x));
+
 struct gdtr
 {
 	uint16_t limit;
@@ -64,4 +70,6 @@ struct gdtr
 
 void load_gdt(struct gdtr *gdt);
 
+void print_stack(void *sp, void *sf);
+
 #endif

include/nanoshell/commands.h

@@ -0,0 +1,25 @@
+#ifndef NANOSHELL_COMMANDS_H
+#define NANOSHELL_COMMANDS_H
+
+#define COMMAND_LENGTH_MAX 256
+
+#define COMMAND_NB 4
+#define HALT_COMMAND "halt"
+#define STACK_COMMAND "stack"
+#define REBOOT_COMMAND "reboot"
+#define SHUTDOWN_COMMAND "shutdown"
+
+typedef struct
+{
+	char *name;
+	void (*handler)(char *args);
+} command_t;
+
+extern command_t commands[COMMAND_NB];
+
+void halt(char *args);
+void stack(char *args);
+void reboot(char *args);
+void shutdown(char *args);
+
+#endif

include/nanoshell/shell.h

@@ -0,0 +1,8 @@
+#ifndef NANOSHELL_SHELL_H
+#define NANOSHELL_SHELL_H
+
+#include "commands.h"
+
+void execute(char *command);
+
+#endif

src/kernel.c

@@ -1,10 +1,8 @@
 #include <stdbool.h>
 #include <stddef.h>
 
-#include "CPU/mode.h"
+#include "CPU/GDT.h"
 #include "IO/terminal.h"
-#include "IO/write.h"
-#include "IO/printk.h"
 
 #if defined(__linux__)
 #error "You are not using a cross-compiler, you will most likely run into trouble"

src/libc/string/strcmp.c

@@ -2,7 +2,12 @@
 
 int strcmp(const char *str1, const char *str2)
 {
-	while (*str1 && *str1 == *str2)
+	while (*str1 && *str2 && *str1 == *str2)
+	{
+		if (*str1 != *str2)
+			return *str1 - *str2;
 		str1++;
+		str2++;
+	}
 	return *str1 - *str2;
 }

src/nanoshell/commands.c

@@ -0,0 +1,8 @@
+#include "nanoshell/shell.h"
+
+command_t commands[] = {
+	{ "reboot", reboot },
+	{ "shutdown", shutdown },
+	{ "halt", halt },
+	{ "stack", stack },
+};

src/nanoshell/commands/halt.c

@@ -0,0 +1,7 @@
+#include "nanoshell/commands.h"
+#include "utils.h"
+
+void halt(__unused char *args)
+{
+	asm("cli; hlt");
+}

src/nanoshell/commands/reboot.c

@@ -0,0 +1,17 @@
+#include "nanoshell/commands.h"
+#include "CPU/port.h"
+#include "utils.h"
+#include <stdint.h>
+
+
+void reboot(__unused char *args)
+{
+    uint8_t good = 0x02;
+    while (good & 0x02)
+        good = inb(0x64);
+    outb(0x64, 0xFE);
+
+loop:
+	asm volatile("hlt");
+	goto loop;
+}

src/nanoshell/commands/shutdown.c

@@ -0,0 +1,8 @@
+#include "nanoshell/commands.h"
+#include "CPU/port.h"
+#include "utils.h"
+
+void shutdown(__unused char *args)
+{
+	outw(0x604, 0x2000); // QEMU specific
+}

src/nanoshell/commands/stack.c

@@ -0,0 +1,14 @@
+#include "CPU/GDT.h"
+#include "nanoshell/commands.h"
+#include "utils.h"
+
+void stack(__unused char *args)
+{
+	void *sp;
+	void *sf;
+
+	GET_STACK_POINTER(sp);
+	GET_STACK_FRAME(sf);
+
+	print_stack(sp - 16, sf + 16);
+}

src/nanoshell/shell.c

@@ -0,0 +1,17 @@
+#include <string.h>
+#include "nanoshell/shell.h"
+#include "IO/printk.h"
+
+void execute(char *command)
+{
+	int i;
+	for (i = 0; i < COMMAND_NB; i++)
+	{
+		if (strcmp(commands[i].name, command) == 0)
+		{
+			commands[i].handler(command);
+			return;
+		}
+	}
+	printk("Unknown command: %s\n", command);
+}

src/system/IO/init.c

@@ -13,15 +13,20 @@ uint16_t *terminal_buffer = (uint16_t *)0xB8000;
 void terminal_motd(void)
 {
 	terminal_setcolor(vga_entry(VGA_COLOR_LIGHT_GREEN, VGA_COLOR_BLACK));
-	terminal_writestring("        :::      :::::::::\n");
-	printk("       :+:      :+:    :+:\n");
-	printk("     +:+ +:+         +:+  \n");
-	printk("   +#+  +:+       +#+     \n");
-	printk(" +#+#+#+#+#+   +#+        \n");
-	printk("      #+#    #+#          \n");
-	printk("     ###   ########.kfs   ");
-	terminal_setcolor(vga_entry(VGA_COLOR_LIGHT_BLUE, VGA_COLOR_BLACK));
-	terminal_writestring("By gboucett\n\n");
+	if (!term_cur)
+	{
+		printk("        :::      :::::::::\n");
+		printk("       :+:      :+:    :+:\n");
+		printk("     +:+ +:+         +:+  \n");
+		printk("   +#+  +:+       +#+     \n");
+		printk(" +#+#+#+#+#+   +#+        \n");
+		printk("      #+#    #+#          \n");
+		printk("     ###   ########.kfs   ");
+		terminal_setcolor(vga_entry(VGA_COLOR_LIGHT_BLUE, VGA_COLOR_BLACK));
+		printk("By gboucett\n\n");
+	}
+	terminal_setcolor(vga_entry(VGA_COLOR_LIGHT_CYAN, VGA_COLOR_BLACK));
+	printk("This is TTY%d\n\n", term_cur);
 }
 
 void terminal_initialize(void)

src/system/IO/printk/printk.c

@@ -87,13 +87,20 @@ int print_hex(va_list *args)
 	return i;
 }
 
+int print_pointer(va_list *arg)
+{
+	terminal_writestring("0x");
+	return print_hex(arg) + 2;
+}
+
 static format_t formats[] = {
 	{'c', print_char},
 	{'%', print_percent},
 	{'s', print_string},
 	{'u', print_uint},
 	{'d', print_int},
 	{'x', print_hex},
+	{'p', print_pointer},
 };
 
 int printk(const char *format, ...)

src/system/IO/terminal.c

@@ -4,8 +4,11 @@
 #include "IO/keyboard.h"
 #include <string.h>
 #include <ctype.h>
+#include "nanoshell/shell.h"
 
 static size_t PS1_end = 0;
+static char command[COMMAND_LENGTH_MAX];
+static int index = 0;
 
 static void terminal_putentryat(char c, uint8_t color, size_t x, size_t y)
 {
@@ -63,7 +66,27 @@ static void terminal_screen(unsigned char c)
 void terminal_entry(unsigned char c)
 {
 	if (isprint(c) || c == '\n' || c == '\b')
+	{
+		if (c == '\n')
+		{
+			command[index] = '\0';
+			prompt = false;
+			terminal_putchar('\n');
+			execute(command);
+			prompt = true;
+			terminal_prompt();
+			index = 0;
+			return ;
+		}
+		else if (c != '\n' && c != '\b')
+			command[index++] = c;
+		else if (c == '\b')
+		{
+			if (index > 0)
+				index--;
+		}
 		terminal_putchar(c);
+	}
 	if (c == UP || c == DOWN || c == LEFT || c == RIGHT)
 		terminal_update_cursor(c);
 	if (IS_F(c))

src/system/boot/GDT/print_stack.c

@@ -0,0 +1,40 @@
+#include "CPU/GDT.h"
+#include <stddef.h>
+#include "IO/printk.h"
+#include "IO/terminal.h"
+
+static void fixed_print(uint8_t c)
+{
+	uint8_t u = c & 0x0F;
+	uint8_t d = (c & 0xF0) >> 4;
+	char *hex = "0123456789ABCDEF";
+
+	printk("%c%c ", hex[d], hex[u]);
+}
+
+void print_stack(void *sp, void *sf)
+{
+	uint8_t color;
+
+	// Print a hex dump of the stack.
+	size_t i = 0;
+	while (sp < sf)
+	{
+		if (i % 16 == 0)
+		{
+			color = vga_entry_color(VGA_COLOR_MAGENTA, VGA_COLOR_BLACK);
+			terminal_setcolor(color);
+			printk("%p: ", sp);
+			color = vga_entry_color(VGA_COLOR_LIGHT_GREY, VGA_COLOR_BLACK);
+			terminal_setcolor(color);
+		}
+		fixed_print(*(uint8_t *)sp);
+		sp++;
+		i++;
+		if (i % 16 == 0)
+		{
+			terminal_putchar('\n');
+		}
+	}
+	printk("\n\n");
+}