feature: functional shell with help and merdella commands

TOOD: reboot, poweroff, echo, color

.gitignore

@@ -2,3 +2,4 @@ build
 obj
 .*
 compile_commands.json
+tags

headers/keyboard.h

@@ -1,5 +1,7 @@
 #pragma once
 
+#include <stdint.h>
+
 static const char *keymap[128] = {
     [2] = "1!",   [3] = "2@",   [4] = "3#",  [5] = "4$",  [6] = "5%",
     [7] = "6^",   [8] = "7&",   [9] = "8*",  [10] = "9(", [11] = "0)",
@@ -93,6 +95,11 @@ static const char *keymap[128] = {
 #define KEY_RIGHT                0x4D
 #define KEY_SPACE                0x39
 #define KEY_UP                   0x48
-#define KET_LEFT_SHIFT           0x2A
+#define KEY_LEFT_SHIFT           0x2A
 #define KEY_RIGHT_SHIFT          0x36
 #define KEY_CAPSLOCK             0x3A
+
+struct key_event {
+	uint8_t c;
+	uint8_t scan_code;
+};

headers/shell.h

@@ -0,0 +1,49 @@
+#pragma once
+
+#define PROMPT "> "
+
+static const char *POOP =
+    "        /           ____/                   /       _           \\\n"
+    "      _/        ___/_                      /       / \\___        \\_\n"
+    "     /        _/'-,  `---._               /       /      \\_        \\\n"
+    "    /  ______/(0} `, , ` , )             /       /         \\_       \\\n"
+    "   /   V          ; ` , ` (             /       /      ,'~~~~~~`,    \\\n"
+    "  |    `.____,- '  (,  `  , )          /       /       :`,-'\"\"`. \";   "
+    "|\n"
+    "  |      `-------._);  ,  ` `,        /       /        \\;:      )``:  |\n"
+    " /       /      )  ) ; ` ,,  :       /       /          ``      : ';   "
+    "\\\n"
+    "/       /      (  (`;:  ; ` ;:\\     /       /                   ;;;,    "
+    "\\\n"
+    "|      /       (:  )``;:;;)`'`'`--./       /     ____       _,-';;`     "
+    "|\n"
+    "|      |       :`  )`;)`)`'   :   /       / ~~~~~    ~~~`--',.;;;|      "
+    "|\n"
+    "|      |       `--;~~~~~      `  /       /,  \"  \"   \"` \",, \\ ;`` |   "
+    "   |\n"
+    "|      |         ( ;         ,  /       /         ;      `; ;    |      "
+    "|\n"
+    "|      |         (; ; ;      ` /       /         ,`       ` :    |        "
+    "><\n"
+    "|      |          (; /        /       /          ` ;     ; :     |\n"
+    "|      \\          ;(_; ;  :  /       /` ; ; ,,,\"\"\";}     `;      /    "
+    "><\n"
+    "\\       \\         : `; `; ` /       /,;,''''   );;`);     ;     / ><    "
+    "    ><\n"
+    " \\       |        ;' :;   ;/       /          (;` :( ; ,  ;    |         "
+    "><\n"
+    "  |      |        |, `;; ,/       /           `)`; `(; `  `;   |     "
+    "(`\\\n"
+    "  |       \\       ;  ;;  ``:     /             `).:` \\;,   `. /      _> "
+    ")_\n"
+    "   \\       \\_  ,-'   ;`;;:;`    /              ;;'`;;  `)   )/    ,-' "
+    ",-. `;\n"
+    "    \\        \\_ ~~~,-`;`;,\"    /               ~~~~~  ,-'   ;     "
+    "`\"\"/  /\"\"\n"
+    "     \\_        \\___\"\"\"/\"\"     /                       `\"\"/\"\"  "
+    "\n";
+
+typedef enum { HELP, REBOOT, POWEROFF, ECHO, COLOR, MERDELLA, ERROR } CMD_TOK;
+
+void reboot(void);
+void shell_init(void);

headers/terminal.h

@@ -1,5 +1,6 @@
 #pragma once
 
+#include "keyboard.h"
 #include <stdbool.h>
 #include <stddef.h>
 #include <stdint.h>
@@ -14,6 +15,7 @@ struct screen {
 	size_t column;
 	uint8_t color;
 	uint16_t buffer[VGA_WIDTH * VGA_HEIGHT];
+	char line[256];
 };
 
 enum vga_color {
@@ -35,13 +37,16 @@ enum vga_color {
 	VGA_COLOR_WHITE = 15,
 };
 
+enum cursor_direction { LEFT, RIGHT, UP, DOWN };
+
 void terminal_initialize(void);
 void terminal_setcolor(uint8_t color);
-void terminal_putentryat(char c, uint8_t color, size_t x, size_t y);
 int terminal_putchar(char c);
 int terminal_write(const char *data, size_t size);
 int terminal_writestring(const char *data);
 int terminal_writelong(long number);
 void terminal_set_screen(int pos);
-uint8_t terminal_getkey(void);
+struct key_event terminal_getkey(void);
 void update_cursor(void);
+void move_cursor(int direction);
+struct screen *get_screen(void);

src/kernel.c

@@ -1,4 +1,5 @@
-#include "kprintf.h"
+#include "gdt.h"
+#include "shell.h"
 #include "terminal.h"
 
 #include <stdbool.h>
@@ -21,11 +22,6 @@ void kernel_main(void)
 	/* Initialize terminal interface */
 	terminal_initialize();
 
-	/* Newline support is left as an exercise. */
-	for (int i = 100; i; i--)
-		kprintf(0, "%d\n", i);
-	void initGdt();
-	kprintf(0, "mange ta mere avec ton argument a kprintf fdp\n");
-	while (true)
-		terminal_getkey();
+	/* initGdt(); */
+	shell_init();
 }

src/shell/exec.c

@@ -0,0 +1,111 @@
+#include "kprintf.h"
+#include "shell.h"
+#include "string.h"
+#include "terminal.h"
+
+extern struct screen *screen;
+
+static CMD_TOK find_command(char *line)
+{
+	size_t i = 0;
+	bool uwu = false;
+	CMD_TOK command = ERROR;
+
+	if (!line[0])
+		return command;
+	while (line[i]) {
+		if (line[i] == ' ') {
+			uwu = true;
+			break;
+		}
+		i++;
+	}
+	line[i] = '\0';
+	if (!strcmp(line, "help"))
+		command = HELP;
+	else if (!strcmp(line, "reboot"))
+		command = REBOOT;
+	else if (!strcmp(line, "poweroff"))
+		command = POWEROFF;
+	else if (!strcmp(line, "echo"))
+		command = ECHO;
+	else if (!strcmp(line, "color"))
+		command = COLOR;
+	else if (!strcmp(line, "merdella"))
+		command = MERDELLA;
+	else
+		kprintf(0, "invalid command: %s\n", line);
+	if (uwu)
+		line[i] = ' ';
+	return command;
+}
+
+static void read_line(char *buf, size_t size)
+{
+	size_t i = 0;
+	struct key_event ev;
+	uint8_t prev_scan_code = 0;
+
+	while (1) {
+		ev = terminal_getkey();
+		if (ev.c == '\n')
+			break;
+		if (prev_scan_code != ev.scan_code && ev.scan_code) {
+			if (ev.scan_code == KEY_BACKSPACE && i) {
+				buf[--i] = '\0';
+				move_cursor(LEFT);
+				terminal_putchar(' ');
+				move_cursor(LEFT);
+			}
+			if (ev.c && i < size - 1) {
+				kprintf(0, "%c", ev.c);
+				buf[i++] = ev.c;
+			}
+			if (i >= size)
+				break;
+		}
+		prev_scan_code = ev.scan_code;
+	}
+	kprintf(0, "\n");
+	buf[i] = '\0';
+}
+
+void shell_init(void)
+{
+	while (1) {
+		kprintf(0, PROMPT);
+		read_line(screen->line, sizeof(screen->line));
+		switch (find_command(screen->line)) {
+		case HELP:
+			kprintf(0, "Welcome to bozOShell, the shell of "
+			           "bozOS\nAvailable commands: help, reboot, "
+			           "poweroff, echo, color, merdella\n");
+			break;
+		case REBOOT:
+			kprintf(0, "rebooting\n");
+			break;
+		case POWEROFF:
+			kprintf(0, "powering off\n");
+			break;
+		case ECHO:
+			kprintf(0, "echoing\n");
+			break;
+		case COLOR:
+			kprintf(0, "coloring\n");
+			break;
+		case MERDELLA: {
+			kprintf(0, POOP);
+			if (!strcmp("--credits", strchr(screen->line, ' ') + 1))
+				kprintf(
+				    0,
+				    "\nThis ascii masterpiece has been created "
+				    "by Targon (/)\n");
+			break;
+		}
+		case ERROR:
+			break;
+		default:
+			break;
+		}
+	}
+}

src/terminal/get.c

@@ -1,31 +1,32 @@
 #include <stdbool.h>
 
 #include "keyboard.h"
-#include "kprintf.h"
 #include "sys/io.h"
 #include "terminal.h"
 
-uint8_t terminal_getkey(void)
+struct key_event terminal_getkey(void)
 {
 	static bool caps_mode = false;
 	static uint8_t prev_scan_code = 0;
+	struct key_event ev = {0};
 	uint8_t scan_code;
 
 	scan_code = inb(KEYBOARD_PORT);
 	if (scan_code == 0x3A || scan_code == 0x58) {
 		caps_mode = !caps_mode;
 		outb(0xED, (caps_mode << 2)); // turn on/off capslock led
-	}
-	else if (scan_code == KEY_RIGHT_SHIFT || scan_code == KET_LEFT_SHIFT)
+	} else if (scan_code == KEY_RIGHT_SHIFT || scan_code == KEY_LEFT_SHIFT)
 		caps_mode = true;
-	else if (scan_code == KEY_RIGHT_SHIFT + 128 || scan_code == KET_LEFT_SHIFT + 128)
+	else if (scan_code == KEY_RIGHT_SHIFT + 128 ||
+	         scan_code == KEY_LEFT_SHIFT + 128)
 		caps_mode = false;
 	else if (scan_code != prev_scan_code && prev_scan_code != 0) {
 		if (scan_code < 128 && keymap[scan_code])
-			kprintf(0, "%c", keymap[scan_code][caps_mode]);
+			ev.c = keymap[scan_code][caps_mode];
 		if (scan_code >= KEY_F1 && scan_code <= KEY_F10)
 			terminal_set_screen(scan_code - KEY_F1);
 	}
 	prev_scan_code = scan_code;
-	return scan_code;
+	ev.scan_code = scan_code;
+	return ev;
 }

src/terminal/put.c

@@ -129,3 +129,46 @@ void update_cursor(void)
 	outb(0x3D4, 0x0E);
 	outb(0x3D5, (pos >> 8) & 0xFF);
 }
+
+void move_cursor(int direction)
+{
+
+	switch (direction) {
+	case LEFT:
+		if (screen->column) {
+			screen->column--;
+		} else if (screen->row) {
+			screen->column = VGA_WIDTH - 1;
+			screen->row--;
+		}
+		break;
+	case RIGHT:
+		if (screen->column < VGA_WIDTH - 1) {
+			screen->column++;
+		} else if (screen->row < VGA_HEIGHT - 1) {
+			screen->column = 0;
+			screen->row++;
+		} else {
+			terminal_new_line();
+		}
+		break;
+	case UP:
+		break;
+	case DOWN:
+		break;
+	default:
+		break;
+	}
+
+	uint16_t pos = screen->row * VGA_WIDTH + screen->column;
+
+	outb(0x3D4, 0x0F);
+	outb(0x3D5, pos & 0xFF);
+	outb(0x3D4, 0x0E);
+	outb(0x3D5, (pos >> 8) & 0xFF);
+}
+
+struct screen *get_screen(void)
+{
+	return screen;
+}