Got memory info from multiboot & minor adjustments

kernel/src/tty.c

@@ -1,4 +1,5 @@
 #include <kernel.h>
+#include <system.h>
 #include <tty.h>
 
 struct {
@@ -6,14 +7,17 @@ struct {
 	size_t col;
 	uint8_t attr;
 	uint8_t* buf;
+	size_t updateWait;
 } ctx;
 
-void tty_init(void) {
+int tty_init(void) {
 	ctx.row = 0;
 	ctx.col = 0;
 	ctx.attr = 0x07;
 	ctx.buf = (uint8_t*)VGA_MEMORY;
 	tty_clear();
+
+	return 0;
 }
 
 void tty_clear(void) {
@@ -27,6 +31,31 @@ void tty_setattr(uint8_t attr) {
 	ctx.attr = attr;
 }
 
+void tty_enableCursor(uint8_t start, uint8_t end) {
+	outb(0x3d4, 0x0a);
+	outb(0x3d5, (inb(0x3d5) & 0xc0) | start);
+	outb(0x3d4, 0x0b);
+	outb(0x3d5, (inb(0x3d5) & 0xe0) | end);
+}
+
+void tty_disableCursor(void) {
+	outb(0x3d4, 0x0a);
+	outb(0x3d5, 0x20);
+}
+
+void tty_updateCursor(void) {
+	if (ctx.updateWait > 0) {
+		ctx.updateWait--;
+		return;
+	}
+
+	uint16_t pos = ctx.row * VGA_WIDTH + ctx.col;
+	outb(0x3d4, 0x0f);
+	outb(0x3d5, (uint8_t)pos);
+	outb(0x3d4, 0x0e);
+	outb(0x3d5, (uint8_t)(pos >> 8));
+}
+
 // TODO:
 void tty_scroll(void) {
 	ctx.row = 0;
@@ -44,8 +73,7 @@ void tty_putc(char c) {
 	if (c == '\n') { 
 		ctx.col = 0;
 		ctx.row++;
-		if (ctx.row >= VGA_HEIGHT) tty_scroll();
-		return;
+		goto scroll_check;
 	}
 
 	tty_putat(c, ctx.row, ctx.col++);
@@ -54,10 +82,20 @@ void tty_putc(char c) {
 		ctx.row++;
 	}
 
+scroll_check:
 	if (ctx.row >= VGA_HEIGHT) tty_scroll();
+	tty_updateCursor();
+}
+
+void tty_write(char* buf, size_t len) {
+	ctx.updateWait = len - 1;
+	for (int i = 0; i < len; i++) tty_putc(buf[i]);
 }
 
 void tty_puts(char* s) {
-	while (*s != '\0') tty_putc(*s++);
+	size_t len = 0;
+	char* p = s;
+	while (*p++ != '\0') len++;
+	tty_write(s, len);
 }