Added AMAZING boot menu to KBOOT

boot/stage2/menu.c

@@ -0,0 +1,73 @@
+#include "stdarg.h"
+#include "stdint.h"
+#include "string.h"
+#include "stdio.h"
+#include "menu.h"
+
+/*
+ * The reason we subtract one from the width and height (or length) is because 
+ * we use the (in this example) width to offset from the (in this example) x 
+ * position. If something has a width of 1 character, the end of it should be 
+ * at 'x + w', so if 'w' were 1, it would be off by one. Therefore we subtract 
+ * one from the given dimensions.
+ */
+
+void rect(uint32_t x, uint32_t y, uint32_t _w, uint32_t _h) {
+	if (_w < 2 || _h < 2) return;
+	uint32_t w = _w - 1;
+	uint32_t h = _h - 1;
+	
+	// Top
+	putat(y, x, CORNER_TL);
+	for (size_t dx = 1; dx < w; dx++) putat(y, x + dx, LINE_H);
+	putat(y, x + w, CORNER_TR);
+
+	// Sides
+	for (size_t dy = 1; dy < h; dy++) {
+		putat(y + dy, x, LINE_V);
+		putat(y + dy, x + w, LINE_V);
+	}
+
+	// Bottom
+	putat(y + h, x, CORNER_BL);
+	for (size_t dx = 1; dx < w; dx++) putat(y + h, x + dx, LINE_H);
+	putat(y + h, x + w, CORNER_BR);
+}
+
+void fill(uint32_t x, uint32_t y, uint32_t w, uint32_t h, char c) {
+	// We don't add one to the dimensions here
+	for (size_t dy = 0; dy < h; dy++) {
+		for (size_t dx = 0; dx < w; dx++) {
+			putat(y + dy, x + dx, c);
+		}
+	}
+}
+
+void hline(uint32_t x, uint32_t y, uint32_t _len) {
+	uint32_t len = _len - 1;
+	putat(y, x, LINE_T_RIGHT);
+	for (size_t dx = 1; dx < len; dx++) putat(y, x + dx, LINE_H);
+	putat(y, x + len, LINE_T_LEFT);
+}
+
+void vline(uint32_t x, uint32_t y, uint32_t _len) {
+	uint32_t len = _len - 1;
+	putat(y, x, LINE_T_DOWN);
+	for (size_t dy = 1; dy < len; dy++) putat(y + dy, x, LINE_V);
+	putat(y + len, x, LINE_T_UP);
+}
+
+void text(uint32_t x, uint32_t y, char* fmt, ...) {
+	va_list args;
+	va_start(args, fmt);
+	char buf[256];
+	vsnprintf(buf, 256, fmt, args);
+	va_end(args);
+
+	uint32_t len = strlen(buf);
+	uint32_t basex = x - len / 2;
+
+	size_t i = 0;
+	while (buf[i] != '\0') putat(y, basex + i, buf[i++]);
+}
+