Moved i/o content to kerno.c

Added function for integer -> string (library pending)
Modified makefile to reflect use of include/ dir

Makefile

@@ -5,10 +5,10 @@ AS      := $(CROSS)as
 CC      := $(CROSS)gcc
 LD      := $(CROSS)ld
 QEMU	:= qemu-system-i386
+INCLUDES:= include/
 
-
+CFLAGS  := -I $(INCLUDES) -O2 -Wall -Wextra -ffreestanding -nostdlib -lgcc -g
-CFLAGS  := -ffreestanding -nostdlib -lgcc -g
+LDFLAGS := -T linker.ld -nostdlib 
-LDFLAGS := -T linker.ld -nostdlib
 
 SRC_DIR := src
 OBJ_DIR := obj
@@ -58,9 +58,17 @@ clean:
 iso: $(OUT_ISO)
 
 .PHONY: run
-run:
+run: $(OUT_ELF)
 	$(QEMU) -kernel $(OUT_ELF)
 
+.PHONY: debug
+debug:
+	$(QEMU) -s -S -kernel $(OUT_ELF)
+
 .PHONY: run_iso
 run_iso:
 	$(QEMU) -cdrom $(OUT_ISO)
+
+.PHONY: debug_iso
+debug_iso:
+	$(QEMU) -s -S -cdrom $(OUT_ISO)

include/kernio.h

@@ -0,0 +1,35 @@
+#ifndef KERNIO_H
+#define KERNIO_H
+#define VGA_GRID_COLS 79
+#define VGA_GRID_ROWS 25
+#include <stdint.h>
+
+/*
+ * CONSTANTS AND VARIABLES
+ */
+
+//Information on the VGA buffer
+
+extern volatile uint16_t* const vga_buffer;
+
+//grid is top left origin. This is our cursor!
+extern int cursor_col;
+extern int cursor_row;
+extern uint16_t vga_attributes; // Black background, White foreground
+
+
+/*
+ * Functions
+ */
+
+//Clear the VGA buffer
+void vga_clear();
+//Put a character in the VGA buffer and move the cursor to the right by one
+void vga_putc(char c);
+void vga_set_attributes(uint8_t attributes);
+void vga_print(const char* out);
+void vga_println(const char* out);
+
+
+
+#endif

src/kernio.c

@@ -0,0 +1,57 @@
+#include "kernio.h"
+#include <stddef.h>
+
+/*
+ * VARS
+ */
+
+int cursor_col = 0;
+int cursor_row = 0;
+volatile uint16_t* const vga_buffer = (uint16_t*)0xB8000;
+uint16_t vga_attributes = 0x0F00;
+
+void vga_clear() {
+	for (int col = 0; col < VGA_GRID_COLS; col ++) {
+		for (int row = 0; row < VGA_GRID_ROWS; row ++) {
+            //works out to iterating every cell
+			const size_t index = (VGA_GRID_COLS * row) + col;
+            //vga buffer looks something like xxxxyyyyzzzzzzzz
+            //x=bg color
+            //y=fg color
+            //c=character to use
+            //Therefore, to write, we just take our color data and tack on the character to the end.
+			vga_buffer[index] = vga_attributes | ' '; //blank out
+		}
+	}
+}
+
+void vga_putc(char c)
+{
+    //Check for some freaky escape character first
+    if(c == '\n') {
+        cursor_col = 0;
+        cursor_row = (cursor_row + 1) % 25;
+        return;
+    }
+        //Calculate where in the vga buffer to put the character
+		const size_t index = (VGA_GRID_COLS * cursor_row) + cursor_col;
+        //VGA buffer cell consists of the first half attributes, second half character
+		vga_buffer[index] = vga_attributes | c;
+		cursor_col++;
+}	
+
+void vga_set_attributes(uint8_t attributes) {
+     vga_attributes = ((uint16_t)attributes) << 8;
+}
+
+
+void vga_print(const char* out)
+{
+	for (int i = 0; out[i] != '\0'; i++)
+        vga_putc(out[i]);
+}
+
+void vga_println(const char* out) {
+    vga_print(out);
+    vga_print("\n");
+}

src/main.c

@@ -1,55 +1,30 @@
-// Reworked sample code from OSDev! Stripped down some of the extra stuff to leave as an exercise.
+//Our own code, at this point...
-//Headers provided by GCC :). No need for libs! We don't even have those yet.
+//#include <stddef.h>
-#include <stddef.h>
 #include <stdint.h>
+#include "kernio.h"
 
+//convert digits from int num to buffer buf. in hex. This is 32 bit only for now!
+//WARN: integer is written from right to left into the buffer, and will halt if the buffer is too small.
+void i_to_str(uint32_t num, char* buf, int size) {
+    //null terminate the string
+    buf[--size] = '\0';
+    while(size > 0 && (num) != 0){
+        int isolated_num = num % 0x10;
+        if(isolated_num > 9){
+            isolated_num+=7;
+        }
+        buf[--size] = '0' + isolated_num;
+        num/=0x10;
+    }
 
-//VGA buffer is the easiest way to write to the screen at this stage. it's just a massive array with two datapoints: what color, and what character?
+    //now shift the whole thing to the left
-//array starts at the absolute address 0xB8000
+    if(size != 0) {
-volatile uint16_t* vga_buffer = (uint16_t*)0xB8000;
+        while(buf[size]!='\0') {
-//the VGA buffer is 80x25 to represent the screen.
+            *buf = buf[size];
-const int GRID_COLS = 80;
+            buf++;
-const int GRID_ROWS = 25;
+        } 
-
+        *buf = '\0'; 
-
+    }
-//grid is top left origin. This is our cursor!
-int cursor_col = 0;
-int cursor_row = 0;
-uint16_t term_color = 0x0F00; // Black background, White foreground
-
-
-//wipe the screen
-void term_clear() {
-	for (int col = 0; col < GRID_COLS; col ++) {
-		for (int row = 0; row < GRID_ROWS; row ++) {
-            //works out to iterating every cell
-			const size_t index = (GRID_COLS * row) + col;
-            //vga buffer looks something like xxxxyyyyzzzzzzzz
-            //x=bg color
-            //y=fg color
-            //c=character to use
-            //Therefore, to write, we just take our color data and tack on the character to the end.
-			vga_buffer[index] = term_color | ' '; //blank out
-		}
-	}
-}
-
-// 
-void term_printc(char c)
-{
-		const size_t index = (GRID_COLS * cursor_row) + cursor_col; //where am i puttin it
-		vga_buffer[index] = term_color | c; //put it there by putting color+char into that spot in the array
-		cursor_col++; //next time put it in the next spot.
-}	
-
-//print a string!
-void term_println(const char* out)
-{
-	for (int i = 0; out[i] != '\0'; i++) 
-		term_printc(out[i]);
-    //go to the next line for a println func.
-    cursor_col = 0;
-    cursor_row++;
 }
 
 
@@ -58,10 +33,11 @@ void kern_main()
 {
 
     //wipe the screen
-	term_clear();
+	vga_clear();
 
 	//IT IS TIME. TO PRINT.
-	term_println("hello my chungus world");
+    char lol[5];
-    term_println(":100:");
+    i_to_str(0xCAFEBABE, lol, 5); 
+	vga_println(lol);
 }