move assembly files into src directory

src/console.asm

@@ -0,0 +1,69 @@
+; Reads a line from the keyboard and fills the specified buffer with it
+; Does not support Shift or any other special keys
+; Arguments:
+; r1 - pointer to the buffer
+; Result:
+; r1 - pointer to the same buffer
+; Clobbers: r2, r3, r4, r5, r6, r7
+pub read_line:
+	mov r6, 1
+	lsl r6, r6, 16
+	sub r6, r6, 32 ; Calculating the address to the shift LUT
+	mov r2, 0 ; Storing the shift status here
+	mov r4, 0 ; Storing the last key here, so we don't repeat the same key
+	mov r3, r1 ; The pointer to after the last character
+
+	read_line_keyloop:
+		keyboard r5
+		
+		cmp r5, r4
+		je read_line_keyloop ; If the current key is same as previous, we loop
+		mov r4, r5 ; Storing current key as previous
+		
+		cmp r5, 0x120 ; Is the key renderable or special?
+		jb read_line_special ; If the key was special, we handle it separately
+		xor r5, r5, 0x100 ; Clearing the "down" bit
+
+		cmp r2, zr ; Checking for shift status
+		je read_line_store ; If shift is up, we skip conversion
+
+		;;; converting from shift-down to shift-up keys
+		add r7, r6, r5 ; Calculating the index of the shift conversion
+		load_8 r5, [r7] ; Loading the shifted value
+		;;;
+
+		read_line_store:
+			store_8 [r3], r5 ; Else, we store the key in the buffer
+			add r3, r3, 1 ; We advance forward
+			; TODO: Writeback
+			jmp read_line_keyloop
+
+		read_line_special:
+			cmp r5, 13 ; Was the key Backspace?
+			je read_line_backspace ; If yes we need to move one character back
+
+			cmp r5, 10 ; Was the key Enter?
+			je read_line_finished ; If so, we're finished
+
+			and r5, r5, 0x1FB ; Mask out the left/right shift direction bit
+			cmp r5, 0x110 ; Was the key Shift Down?
+			and flags, flags, 0x1 ; We care only about equality bit
+			or r2, r2, flags ; If shift was down before, it still is. If it was pressed now, it is down now
+
+			cmp r5, 0x010 ; Was the key Shift Up?
+			and flags, flags, 0x1 ; We care only about equality bit
+			xor flags, flags, 0x1 ; We invert it, i.e. "if it's not up"
+			and r2, r2, flags ; The shift can be kept down if it's not currently up
+
+			jmp read_line_keyloop ; If no special handling, we loop back
+
+		read_line_backspace:
+			cmp r3, r1 ; Compare the current pointer to start of buffer
+			je read_line_keyloop ; If we are at the start, we loop
+			sub r3, r3, 1 ; We move back one character
+			; TODO: Writeback
+			jmp read_line_keyloop
+
+	read_line_finished:
+		store_8 [r3], zr ; We store null at the end so the string is finished
+		jmp r13