Merge pull request #28 from E-Almqvist/dev

Refactor & cleanup

drivers/vga.c

@@ -1,54 +1,61 @@
 // VGA Graphics Library
+#include "vga.h"
 #include "../kernel/io.h"
 
-// VGA base address: 0xb8000
-// Charpos = 0xb8000 + 2(row*80 + col)
-
 // Memory
-#define VIDEO_MEM 	(char*)0xb8000
-#define VIDEO_MEM_MAX	(char*)0xb8fa0
+#define VGA_ADDRESS 	(char*)0xb8000
+#define VGA_ADDRESS_MAX	(char*)0xb8fa0
+
+#define MAX_ROWS 25
+#define MAX_COLS 80
 
-// Global
 static unsigned int cursor_row = 0;
 static unsigned int cursor_col = 0;
 
+void vga_init() {
+	// Disable cursor
+	port_outb(0x3d4, 0x0a);
+	port_outb(0x3d5, 0x20);
+
+	// Clear screen
+	clear_screen();
+}
+
 /*
 	VGA & Memory Functions
 */
-char* get_vga_charpos_pointer(unsigned int col, unsigned int row) { 
-	return (char*)(VIDEO_MEM + 2*((row*80) + col)); 
+char* get_memory_charpos(unsigned int col, unsigned int row) { 
+	return (char*)(VGA_ADDRESS + 2*((row*80) + col)); 
 }
 
 void writechar(char c, unsigned int col, unsigned int row, int attribute_byte) {
-	char* mem = get_vga_charpos_pointer(col, row);
+	if( !attribute_byte ) 
+		attribute_byte = 0x0f;
+
+	char* mem = get_memory_charpos(col, row);
 	*mem = c; 			// Write the character
 	*(mem+1) = attribute_byte;	// Write the attribute_byte
 
 }
 
+void set_cursor_pos(unsigned int col, unsigned int row) {
+	cursor_col = col;
+	cursor_row = row;
+}
+
+
 /*
 	Graphics Functions
 */
 void clear_screen() {
-	// Make all the characters spaces
-	for( char* c = VIDEO_MEM; c <= VIDEO_MEM_MAX; c += 2 )
-		*c = 0x20;
-}
-
-void disable_vga_cursor() {
-	port_outb(0x0a, 0x3d4);
-	port_outb(0x20, 0x3d5);
+	for( int c = 0; c < MAX_COLS; c++ )
+		for( int r = 0; r < MAX_ROWS; r++ )
+			writechar(0x20, c, r, 0xf0);
 }
 
-
 /*
 	General Printing Functions
 */
-void set_cursor_pos(unsigned int x, unsigned int y) {
-	cursor_col = x;
-	cursor_row = y;
-}
-
 void print(char* str, int attribute_byte) {
 	for( char* c = str; *c != '\0'; c++ ) 
 		writechar(*c, (unsigned int)(c - str) + cursor_col, cursor_row, attribute_byte);
@@ -60,8 +67,3 @@ void println(char* str, int attribute_byte) {
 }
 
 
-// VGA Initialization Function
-void vga_init() {
-	disable_vga_cursor();
-	clear_screen();
-}

drivers/vga.h

@@ -1,7 +1,6 @@
-char* get_vga_charpos_pointer(unsigned int col, unsigned int row);
+char* get_memory_charpos(unsigned int col, unsigned int row);
 void writechar(char c, unsigned int col, unsigned int row, int colorcode);
 void clear_screen();
-void disable_vga_cursor();
 void set_cursor_pos();
 void print();
 void println();

kernel/kernel.c

@@ -6,4 +6,10 @@ void main() {
 
 	set_cursor_pos(28, 2);
 	print("eOS Version 0.1 2021", 0xf0);
+
+	/*
+	set_cursor_pos(0, 0);
+	for( int i = 0; i < 255; i++ )
+		println("X", i);
+	*/
 }